Hibbard v. Secretary of Health & Human Services

United States Court of Appeals
for the Federal Circuit
__________________________

JENNIFER HIBBARD,
Petitioner-Appellant,

v.
SECRETARY OF HEALTH AND HUMAN
SERVICES,
Respondent-Appellee.
__________________________

2012-5007
__________________________

Appeal from the United States Court of Federal
Claims in Case No. 07-VV-446, Judge Thomas C.
Wheeler.
___________________________

Decided: November 2, 2012
___________________________

SYLVIA CHIN-CAPLAN, Conway, Homer & Chin-Caplan,
P.C. of Boston, Massachusetts, argued for petitioner-
appellant. On the brief was RONALD C. HOMMER.

GLENN A. MACLEOD, Senior Trial Counsel, Torts
Branch, Civil Division, United States Department of
Justice, of Washington, DC, argued for respondent-
appellee. With him on the brief were TONY WEST, Assis-
tant Attorney General, MARK W. ROGERS, Acting Director,
HIBBARD v. HHS 2

VINCENT J. MATANOSKI, Acting Deputy Director and
GABRIELLE M. FIELDING, Assistant Director.
__________________________

Before LOURIE, BRYSON, and O’MALLEY, Circuit Judges.
Opinion for the court filed by Circuit Judge BRYSON.
Dissenting opinion filed by Circuit Judge O’MALLEY.

BRYSON, Circuit Judge.

Jennifer Hibbard received a flu vaccination in 2003.
She claims that the flu vaccine caused her to develop a
neurological disorder known as dysautonomia, a dysfunc-
tion of the autonomic nervous system. Her theory is that
the vaccine provoked an immune reaction that damaged
her autonomic nerves, and that the injury to her auto-
nomic nerves, known as autonomic neuropathy, resulted
in her dysautonomia. She seeks compensation for her
injury under the National Childhood Vaccine Injury Act of
1986 (“the Vaccine Act”), 42 U.S.C. §§ 300aa-1 to 300aa-
34.

The parties agree that Ms. Hibbard suffers from dy-
sautonomia; the dispute between the parties is whether
her dysautonomia is the result of autonomic neuropathy
caused by the vaccine. Following a two-day hearing, a
special master found that Ms. Hibbard had failed to show
that her dysautonomia resulted from autonomic neuropa-
thy caused by the vaccine she received in 2003. Accord-
ingly, the special master found that she failed to meet her
burden of demonstrating by a preponderance of the evi-
dence that the vaccine resulted in a compensable injury,
as required by the Act, 42 U.S.C. §§ 300aa-13(a)(1)(A) and
300aa-11(c)(1)(C)(ii)(I). On review, the Court of Federal
Claims upheld the special master’s decision. We affirm.
3 HIBBARD v. HHS

I

Ms. Hibbard was 41 years old and working as a first-
grade teacher when she experienced a fainting spell in
May 2003. She felt a wave of heat and lightheadedness,
and she lost consciousness for approximately 10 seconds.
She was taken to an emergency room; a neurological
examination and laboratory tests were normal, and she
was discharged that day. No specific tests were con-
ducted for dysautonomia at that time. The respondent’s
expert later testified that the May episode was an in-
stance of dysautonomia, and Ms. Hibbard’s expert agreed
that the episode was a symptom of autonomic dysfunc-
tion. When Ms. Hibbard saw her primary care physician
in July 2003, she had recovered, but she reported that it
took about a month after the fainting spell before she felt
normal again. At the time of the May episode, Ms.
Hibbard reported that in the past she had experienced
other incidents of fainting or feeling lightheaded.

Several months later, on November 1, 2003, Ms.
Hibbard received a flu vaccination. A week after the
vaccination, Ms. Hibbard began to feel tired, achy, and
nauseated. Her symptoms worsened during an extracur-
ricular outing with some of her students and continued
over the next few days. On November 11, she saw a
physician, who prescribed antibiotics for what he believed
was probably “[e]volving sinusitis.” He also noted that
Ms. Hibbard probably had “some underlying viral respira-
tory infection.” The antibiotics did not alleviate Ms.
Hibbard’s symptoms, and during the following week she
saw two other doctors, including her primary care physi-
cian, Dr. Amy Schoenbaum. Ms. Hibbard reported that
she felt very weak, tired, and dizzy, especially when
standing. Based on a recommendation of one of those
doctors, Ms. Hibbard stopped taking the antibiotics. Both
HIBBARD v. HHS 4

doctors thought that a viral infection might be responsible
for her symptoms.

Ms. Hibbard continued to follow up with Dr.
Schoenbaum. On December 12, 2003, Dr. Schoenbaum
noted that Ms. Hibbard presented with complaints of
“vertigo, weakness, feeling of passing out, some heaviness
and numbness in her extremities.” Dr. Schoenbaum sent
her to an emergency room at that time, where she was
referred to a neurologist. The neurologist considered
Guillain-Barré Syndrome (“GBS”) as a possible diagnosis
but concluded that GBS was unlikely based on Ms.
Hibbard’s medical history and physical examination. Ms.
Hibbard returned to the emergency room the following
day because she was having trouble breathing. She was
admitted to the hospital at that time with a diagnosis of
“malaise,” which remained her principal diagnosis when
she was discharged several days later. Over the next few
months, Ms. Hibbard saw an otoneurologist for vestibular
testing, which did not reveal anything abnormal. Ms.
Hibbard also began seeing a psychiatrist, who initially
prescribed selective serotonin reuptake inhibitor treat-
ment. When Ms. Hibbard did not tolerate that treatment
well, her psychiatrist prescribed a different antidepres-
sant.

Ms. Hibbard’s dizziness and weakness continued, and
she saw Dr. Schoenbaum again on February 27, 2004. Dr.
Schoenbaum encouraged Ms. Hibbard to continue work-
ing with her psychiatrist, because although her symptoms
were “not classic for an anxiety disorder,” she was “ex-
periencing anxiety and depression secondary to the symp-
toms.” Over the next several months, Ms. Hibbard saw a
cardiologist and two neurologists. The cardiologist
checked for mitral valve prolapse, for which Ms. Hibbard
had been treated in the past, but found no definitive
5 HIBBARD v. HHS

evidence of that condition. The first of the two neurolo-
gists, Dr. Louis Caplan, concluded that Ms. Hibbard had
“a postinfectious neuropathy with autonomic features,”
which he referred to as “kind of a Guillain Barré with
partial dysautonomia.” The second neurologist was Dr.
Kenneth Gorson, an expert in GBS. Dr. Gorson reported
that Ms. Hibbard’s detailed neurological examination was
normal and that the “[r]outine nerve conduction studies
were pristine.” Based on his examination, Dr. Gorson
concluded that Ms. Hibbard did not have “electrophysi-
ologic features, nor clinical features, of typical [GBS],” but
he added that it was “certainly possible that she devel-
oped a modest dysautonomic neuropathy following a
nonspecific viral illness or even the flu vaccination back in
November.” He noted that some patients with a condition
known as Postural Orthostatic Tachycardia Syndrome
(“POTS”) have symptoms similar to Ms. Hibbard’s.

The record indicates that POTS is a syndrome in
which the patient’s heart rate increases significantly upon
standing without a significant drop in blood pressure.
POTS is indicative of dysautonomia, but it is a nonspecific
finding. While it can be associated with autonomic neu-
ropathy, it can have other causes as well. To test for
POTS, Dr. Gorson recommended a tilt table test.

On June 16, 2004, Ms. Hibbard underwent a series of
tests of her autonomic nervous system, including a tilt
table test. The tests were conducted by Dr. Christopher
Gibbons under the supervision of Dr. Roy Freeman, a
leading expert on autonomic dysfunction. The tests
resulted in a diagnosis of POTS. In addition to showing
the presence of orthostatic tachycardia (rapid heart rate
upon standing), the tilt table test revealed some drop in
blood pressure when Ms. Hibbard was elevated into the
standing position. The testing also showed “an exagger-
HIBBARD v. HHS 6

ated postural tachycardia . . . on active standing” and
“symptoms of lightheadedness and shortness of breath
while standing.” The results of the other autonomic tests
that Dr. Gibbons and Dr. Freeman administered to Ms.
Hibbard were all in the normal range.

In their report, Drs. Gibbons and Freeman stated that
the overall study was “abnormal” in that “one measure of
sympathetic adrenergic function [the tilt table test for
POTS] was in the pathologic range,” although the meas-
ures of the “sympathetic cholinergic function were in the
normal range.” They reported that the tests showed
“evidence of an exaggerated postural tachycardia.” Al-
though they identified that finding as “a non-specific
finding,” they added that “exaggerated postural tachycar-
dia has been associated with mild or early autonomic
neuropathy and an autonomic neuropathy that involves
the distal vasculature sparing the cardiac autonomic
innervation.” They added that “[o]ther associations have
included cardiovascular deconditioning, cardiac beta
adrenoreceptor supersensitivity and mitral valve
prolapse,” that “fever, volume depletion and dehydration
should be excluded,” and that the same response has been
seen “in patients diagnosed with chronic fatigue syn-
drome.” Dr. Freeman concluded from the testing that “it
is unclear . . . the extent to which autonomic dysfunction
is contributing to her symptoms.”

Ms. Hibbard followed up with another neurologist, Dr.
Peter Novak. As part of his evaluation, Dr. Novak per-
formed another tilt table test. That test again revealed
orthostatic tachycardia. Dr. Novak’s assessment of the
tests was that they showed “moderate cardiac adrenergic
and vasomotor adrenergic impairment with normal
cardiac cholinergic functions,” findings that he found to be
7 HIBBARD v. HHS

“suggestive of the autonomic neuropathy affecting pre-
dominantly sympathetic (adrenergic) fibers.”

II

On June 28, 2007, Ms. Hibbard filed a petition for
compensation under the Vaccine Act. Initially, she
claimed that she suffered from GBS, caused by the flu
vaccine. She later amended her petition to allege that she
had suffered a neurological demyelinating injury. In
support of her petition, Ms. Hibbard submitted an expert
report from Dr. Thomas Morgan, a neurologist. The
respondent submitted an expert report from another
neurologist, Dr. Vinay Chaudhry.

The experts explained that the human nervous sys-
tem is divided between the central nervous system, which
refers to the brain and spinal cord, and the peripheral
nervous system, which includes the rest of the nervous
system. The peripheral nervous system includes the
autonomic nervous system, which controls involuntary
functions such as heart rate, respiratory rate, and perspi-
ration. The autonomic nervous system is further divided
between the sympathetic component and the parasympa-
thetic component, which together keep the body’s internal
systems in balance, a condition known as “homeostasis.”

In his initial report, Dr. Morgan stated that it was his
medical opinion, based on Ms. Hibbard’s medical records,
that she “sustained a post influenza vaccine immuniza-
tion autonomic neuropathy with signs and symptoms well
documented in the record of dysautonomia.” Dr. Morgan
noted that several of Ms. Hibbard’s symptoms involved
the sympathetic nervous system, including POTS, or-
HIBBARD v. HHS 8

thostatic hypotension,1 and sweating abnormalities. He
also noted some parasympathetic symptoms, including
“nasal sinus secretions, flushing, gastrointestinal motility
problems, nausea, vomiting, diarrhea and constipation.”
Dr. Morgan stated that Ms. Hibbard’s condition was
consistent with a variant of GBS known as pandy-
sautonomia, which he explained can be caused by “mo-
lecular mimicry,” in which a vaccine generates an
immune response that attacks the sympathetic nerve
fibers to cause symptoms of dysautonomia. He added that
the development of symptoms of autonomic neuropathy
within ten days to two weeks after the vaccination is
consistent with an autoimmune reaction caused by a
vaccine.

Dr. Chaudhry stated that it was difficult to explain all
of Ms. Hibbard’s symptoms with a single diagnosis. While
Dr. Chaudhry acknowledged that GBS “may rarely pre-
sent with autonomic manifestations as the sole or pre-
dominant feature,” he stated that autonomic
manifestations usually would be accompanied by or-
thostatic hypotension, which is a drop in blood pressure
upon standing without a corresponding rise in heart rate.
He described orthostatic hypotension as not being docu-
mented in Ms. Hibbard’s case. Dr. Chaudhry also noted
that “[g]enerally [POTS] is a chronic syndrome and not an
acute neuropathy like GBS.” In light of Ms. Hibbard’s
symptoms, her normal examination, the limited documen-
tation of abnormalities of autonomic function, her prior
history of fainting, and the multiple other possible diag-
noses, Dr. Chaudhry concluded that Ms. Hibbard did not

1 Orthostatic hypotension was defined by one of the
references in the record as a reduction of systolic blood
pressure of at least 20 mm Hg or diastolic blood pressure
of at least 10 mm Hg within three minutes of standing.
9 HIBBARD v. HHS

“represent[] a GBS syndrome presenting as autonomic
neuropathy.” He added that her symptoms were “far
more than can be explained by” a possible “mild or early
autonomic neuropathy.” For those reasons, Dr. Chaudhry
concluded that there was “no causal link between the flu
vaccine and her multiple symptoms.”

In a supplemental report, Dr. Chaudhry responded to
Dr. Morgan’s report by stating that in his opinion “[t]here
is no objective sign or laboratory test that has demon-
strated that Ms. Hibbard has peripheral neuropathy from
molecular mimicry or any other hypothesis.” Specifically,
Dr. Chaudhry noted that Ms. Hibbard displayed “no
sensory loss, weakness, or reflex change,” that a skin
biopsy test of small sensory fibers and nerve conduction
studies of the large sensory and motor fibers were normal,
and that no spinal fluid changes were documented. He
added that the autonomic laboratory tests that were
performed on Ms. Hibbard did not indicate that she was
suffering from autonomic neuropathy.

The special master who was assigned to the case held
a two-day hearing. During the hearing, Dr. Morgan
explained the rationale for his opinion that Ms. Hibbard
suffered from autonomic neuropathy. Important to his
conclusion was a Mayo Clinic study that described a
retrospective study of POTS patients in an attempt to
determine the cause of POTS. The authors of that study
were specifically interested in determining the extent to
which POTS was associated with autonomic neuropathy.
The authors concluded that at least half of the POTS
patients they studied had neuropathic features, and that
about 50 percent of the patients who were tested had
“evidence of peripheral sudomotor denervation.” Sudomo-
tor denervation involves impaired sudomotor function
(sweat gland function in response to stimulation).
HIBBARD v. HHS 10

Dr. Chaudhry testified that the tests for autonomic
neuropathy that were performed on Ms. Hibbard were
negative, including the “skin sympathetic response test,”
Valsalva maneuver testing, and catecholamine level
testing. Based on those tests, Dr. Chaudhry concluded
that although Ms. Hibbard suffers from autonomic dys-
function, there were “so many symptoms with very little
signs” that it is “hard to put this together and say this is
autonomic neuropathy.” Although Dr. Morgan in his
initial report had identified several of Ms. Hibbard’s
symptoms as signs of autonomic neuropathy, in his testi-
mony at the hearing he acknowledged that other than the
tests for POTS, the objective tests for autonomic neuropa-
thy in the sympathetic nerves were normal.

Following the hearing, the special master directed the
parties to submit post-hearing briefs focusing on the
issues that appeared to be the focus of the dispute. The
special master referred to this court’s decision in Althen v.
Secretary of Health & Human Services, which requires
the petitioner in a Vaccine Act case to show “(1) a medical
theory causally connecting the vaccination and the injury;
(2) a logical sequence of cause and effect showing that the
vaccination was the reason for the injury; and (3) a show-
ing of a proximate temporal relationship between vaccina-
tion and injury.” 418 F.3d 1274, 1278 (Fed. Cir. 2005). As
to the first element of the Althen test, the special master
invited the parties to comment on what he understood to
be Dr. Morgan’s medical theory as to how the flu vaccine
could have caused Ms. Hibbard’s condition—that through
a process known as molecular mimicry, the vaccine had
triggered a response that damaged the myelin around the
pre-ganglionic portion of the sympathetic part of Ms.
Hibbard’s autonomic nervous system. As to the second
part of the Althen test, the special master directed the
parties to explain whether Ms. Hibbard had presented a
11 HIBBARD v. HHS

“logical sequence of cause and effect” by which the flu
vaccine led to her condition. The special master explained
that if Dr. Morgan’s theory is “that the flu vaccine can
lead to demyelination, which is damage to nerves, . . . it
appears that petitioner needs to establish, by a prepon-
derance of the evidence that she suffered from an auto-
nomic neuropathy.” As to the third part of the Althen
test, the special master noted that respondent’s expert
had conceded that Ms. Hibbard’s case satisfied the tempo-
ral relationship factor. In light of that concession, the
special master did not require the parties to address the
timing issue.

In response, Ms. Hibbard agreed with the special
master’s characterization of her “molecular mimicry”
theory of causation, except that she added that the injury
to her nerves could have occurred in an unmyelinated
area of the sympathetic nervous system. She explained:
“Where there is myelin, the mimicry could have been with
the myelin. Where it is unmyelinated, the mimicry could
have been with the proteins contained in the ganglia.”

After receiving the parties’ briefs, the special master
issued a decision denying compensation for Ms. Hibbard.
Although both parties (and the special master) agreed
that Ms. Hibbard suffers from dysautonomia and that she
has POTS, the special master found that “[a] preponder-
ance of the evidence supports a finding that Ms. Hibbard
does not have autonomic neuropathy.” The special master
based that conclusion on his finding that “when Ms.
Hibbard was tested for signs of autonomic neuropathy,
the results were normal.” With respect to Dr. Morgan’s
reliance on the fact that Ms. Hibbard suffers from POTS
as indicating damage to the sympathetic nervous system,
the special master noted that POTS “does not always
mean that the nerves in the autonomic nervous system
HIBBARD v. HHS 12

are damaged,” and that Dr. Morgan had failed “to account
for the substantial number of people who have POTS
without autonomic neuropathy.”

Because Ms. Hibbard’s theory was that the flu vaccine
caused an autoimmune reaction that damaged her sympa-
thetic nerves resulting in dysautonomia, the special
master found that Ms. Hibbard’s failure to prove that she
had autonomic neuropathy doomed her case. Having
found that Ms. Hibbard failed to prove that critical step in
Dr. Morgan’s medical theory of causation, the special
master concluded that Ms. Hibbard did not satisfy the
second part of the Althen test, i.e., she failed to show that
there was a logical sequence of cause and effect showing
that the vaccine was the reason for her injury. For that
reason, the special master stated that it was not neces-
sary to address the other Althen factors.

The Court of Federal Claims affirmed the special
master’s decision. The court described Ms. Hibbard’s
theory of causation as follows: “the flu vaccine, through
molecular mimicry, caused autonomic neuropathy, which
manifested as dysautonomia and POTS.” In light of that
theory of causation, the court ruled, the special master
did not commit legal error by deciding the case solely on
the issue of whether Ms. Hibbard has autonomic neuropa-
thy, which the court described as “the underpinning on
which Ms. Hibbard’s entire case hinges.” As to that issue,
the court concluded that the special master’s finding of
fact was not arbitrary and capricious. The court observed
that although several of the physicians who examined Ms.
Hibbard suspected autonomic neuropathy as a possible
cause of her dysautonomia, the medical evidence was
inconclusive. In particular, the court noted, the special
master had relied heavily on objective test results, which
for the most part were negative as to signs of autonomic
13 HIBBARD v. HHS

neuropathy. The court therefore upheld the special
master’s finding that Ms. Hibbard did not suffer from
autonomic neuropathy.

III

In Vaccine Act cases, we review a ruling by the Court
of Federal Claims de novo, applying the same standard
that it applies in reviewing the decision of the special
master. Cloer v. Sec’y of Health & Human Servs., 654
F.3d 1322, 1330 (Fed. Cir. 2011) (en banc); Moberly v.
Sec’y of Health & Human Servs., 592 F.3d 1315, 1321
(Fed. Cir. 2010). Therefore, we review the rulings of the
special master to determine whether they were “arbitrary,
capricious, an abuse of discretion, or otherwise not in
accordance with law.” Munn v. Sec’y of Health & Human
Servs., 970 F.2d 863, 869 (Fed. Cir. 1992).

The role of appellate review of a special master’s deci-
sion under the arbitrary and capricious standard “is not
to second guess the Special Master’s fact-intensive con-
clusions; the standard of review is uniquely deferential for
what is essentially a judicial process.” Locane v. Sec’y of
Health & Human Servs., 685 F.3d 1375, 1380 (Fed. Cir.
2012), quoting Hodges v. Sec’y of Health & Human Servs.,
9 F.3d 958, 961 (Fed. Cir. 1993); Doe v. Sec’y of Health &
Human Servs., 601 F.3d 1349, 1355 (Fed. Cir. 2010). If
the special master’s conclusion is “based on evidence in
the record that [is] not wholly implausible, we are com-
pelled to uphold that finding as not being arbitrary and
capricious.” Cedillo v. Sec’y of Health & Human Servs.,
617 F.3d 1328, 1338 (Fed. Cir. 2010), quoting Lampe v.
Sec’y of Health & Human Servs., 219 F.3d 1357, 1360
(Fed. Cir. 2000). Put another way, if the special master
“has considered the relevant evidence of record, drawn
plausible inferences and articulated a rational basis for
HIBBARD v. HHS 14

the decision, reversible error will be extremely difficult to
demonstrate.” Hines v. Sec’y of the Dep’t of Health &
Human Servs., 940 F.2d 1518, 1528 (Fed. Cir. 1991).

Because Ms. Hibbard’s injury is not listed on the Vac-
cine Injury Table, 42 U.S.C. § 300aa-14(a), this is an off-
Table case. Moberly, 592 F.3d at 1321-22; Althen, 418
F.3d at 1278. As such, Ms. Hibbard was required to
prove, by a preponderance of the evidence, that the vac-
cine was “not only a but-for cause of the injury but also a
substantial factor in bringing about the injury.” Shyface
v. Sec’y of Health & Human Servs., 165 F.3d 1344, 1352
(Fed. Cir. 1999).

Ms. Hibbard acknowledges in her brief that it is her
burden “to show, by a preponderance of the evidence, in
accordance with [section 300aa-11(c)(1)(C)(ii)], that her
dysautonomia is more likely than not due to her flu
vaccine.” Her theory of causation is that the vaccine
provoked her immune system to attack her autonomic
nerves, causing damage to those nerves that manifested
as dysautonomia. Although at points in her brief Ms.
Hibbard argues that she was not required to show that
she suffers from autonomic neuropathy, her counsel
acknowledged at oral argument that in order for Ms.
Hibbard to recover, “she has to show that she has auto-
nomic neuropathy.” In light of her expert’s theory of
causation, which depended on a showing of autonomic
neuropathy, it was plainly necessary for her to make that
showing in order to satisfy the second of the Althen fac-
tors, which requires demonstrating “a logical sequence of
cause and effect showing that the vaccination was the
reason for the injury,” Althen, 418 F.3d at 1278.2

2 The dissent acknowledges that as part of her
prima facie case Ms. Hibbard was required to show causa-
15 HIBBARD v. HHS

A

Ms. Hibbard argues at some length that it was im-
proper for the special master to focus on the second Al-
then factor, to the exclusion of the other two factors. We
discern no error in the manner in which the special mas-
ter chose to address the Althen factors, however. The
special master acknowledged that the temporal require-
ment (the third Althen factor) was satisfied in this case.
He therefore had no need to discuss that factor in any
detail. As to the requirement that Ms. Hibbard show a
“medical theory causally connecting the vaccination and
the injury” (the first Althen factor), the special master
proceeded by assuming the medical viability of Dr. Mor-
gan’s theory of causation and going directly to the second
Althen factor, i.e., determining whether Dr. Morgan’s
theory accounted for Ms. Hibbard’s injury.

In arguing that the special master improperly short-
circuited the Althen analysis, Ms. Hibbard insists that it
was the special master’s “obligation to determine whether
a flu vaccine can cause dysautonomia and whether it did
so in [her] individual case.” In this case, she contends,
“the special master preemptively determined that an

tion by a preponderance of the evidence. See Doe, 601
F.3d at 1357 (citing cases). Given that Ms. Hibbard has
conceded that in order to satisfy her burden of proof she
had to show that she has autonomic neuropathy, it is not
clear why the dissent regards it as improper for the
special master to have focused on whether she succeeded
in doing so. Although the dissent complains that the
special master should have viewed Ms. Hibbard’s condi-
tion as dysautonomia rather than autonomic neuropathy,
her theory of causation was that the vaccine caused
autonomic neuropathy, which manifested as dysautono-
mia, so it was necessary for her to prove that her dy-
sautonomia resulted from autonomic neuropathy.
HIBBARD v. HHS 16

autonomic neuropathy did not cause [her] dysautonomia.”
Although she claims that the special master erred by
“attacking one element of [her] proposed theory of how
her injury occurred,” it was not error for the special
master to focus first on whether she actually had the
injury that she claims was caused by the vaccine before
addressing the question whether the vaccine actually
caused that injury in her case. If a special master can
determine that a petitioner did not suffer the injury that
she claims was caused by the vaccine, there is no reason
why the special master should be required to undertake
and answer the separate (and frequently more difficult)
question whether there is a medical theory, supported by
“reputable medical or scientific explanation,” by which a
vaccine can cause the kind of injury that the petitioner
claims to have suffered. Althen, 418 F.3d at 1278.

In previous cases, this court has sanctioned an ap-
proach similar to the one taken in this case, in which a
special master has addressed the nature of the injury
suffered before addressing the question whether there is a
viable medical theory by which a vaccine can cause the
injury claimed by the petitioner. See Locane, 685 F.3d
1375; Lombardi v. Sec’y of Health & Human Servs., 656
F.3d 1343 (Fed. Cir. 2011); Brockelschen v. Sec’y of Health
& Human Servs., 618 F.3d 1339 (Fed. Cir. 2010). In each
of those cases, there was a dispute as to the nature of the
petitioner’s injury, and in each case the special master’s
findings on the nature of the injury that the petitioner
incurred was sufficient to resolve the case because the
special master found that the injury the petitioner in-
curred was not one that could have been vaccine-induced
according to the petitioner’s medical theory.

The issue that the special master addressed in this
case is whether Ms. Hibbard suffers from autonomic
17 HIBBARD v. HHS

neuropathy. As Dr. Morgan’s report and testimony made
clear, that was a necessary component of her theory of
vaccine-induced injury. Therefore, even assuming the
medical plausibility of Ms. Hibbard’s theory of causa-
tion—that the vaccine triggered an immune response that
damaged her autonomic nerves—her failure to show that
she had autonomic neuropathy would be fatal to her case.
Given that Ms. Hibbard had to show both the medical
plausibility of her theory of causation and that she suf-
fered an injury consistent with that theory of causation,
there was no reason to require the special master to
address the first question when the answer to that ques-
tion could have no possible effect on the outcome of the
case. As the Court of Federal Claims succinctly put it,

Ms. Hibbard asserts that the flu vaccine, through
molecular mimicry, caused autonomic neuropathy,
which manifested as dysautonomia and POTS. . . .
The special master, therefore, did not commit le-
gal error by deciding Ms. Hibbard’s case solely on
the issue of whether she has autonomic neuropa-
thy, the underpinning on which Ms. Hibbard’s en-
tire case hinges.

Hibbard v. Sec’y of Health & Human Servs., 100 Fed. Cl.
742, 749 (2011).

B

Ms. Hibbard makes the separate legal argument that
the special master and the trial court imposed an unduly
high burden of proof on her by requiring her to show
actual causation in this case. Instead, she argues, the
Althen standard of causation is satisfied—and should
have been regarded as met in this case—by proof that the
vaccine she received can cause the injury she suffered,
HIBBARD v. HHS 18

that the onset of her symptoms occurred within an appro-
priate time period, and that “no likely alternative cause of
her injury has been identified.”

This court has previously rejected the same argu-
ment—that proof that an injury could be caused by a
vaccine and that the injury occurred within an appropri-
ate period of time following the vaccination is sufficient to
require an award of compensation unless the respondent
can prove some other cause for the injury. See Moberly,
592 F.3d at 1323 (“temporal association between a vacci-
nation and a seizure, together with the absence of any
other identified cause for the ultimate neurological injury”
is evidence of causation but does not by itself compel a
finding of causation); Althen, 418 F.3d at 1278 (“neither a
mere showing of a proximate temporal relationship be-
tween vaccination and injury, nor a simplistic elimination
of other potential causes of the injury suffices, without
more, to meet the burden of showing actual causation”).

To the extent that Ms. Hibbard argues that the court’s
decision in Althen relieves petitioners of the obligation to
show actual causation, this court has rejected that con-
tention. Instead, the court has repeatedly held that in off-
Table cases such as this one the task of the special master
is to determine, “based on the record evidence as a whole
and the totality of the case, whether it has been shown by
a preponderance of the evidence that a vaccine caused the
[petitioner’s] injury.” Porter v. Sec’y of Health & Human
Servs., 663 F.3d 1242, 1249-50 (Fed. Cir. 2011), quoting
Lombardi, 656 F.3d at 1351; Stone v. Sec’y of Health &
Human Servs., 676 F.3d 1373, 1379 (Fed. Cir. 2012);
Moberly, 592 F.3d at 1321-22; Andreu v. Sec’y of Health &
Human Servs., 569 F.3d 1367, 1382 (Fed. Cir. 2009).
19 HIBBARD v. HHS

In the recent en banc decision in Cloer v. Secretary of
Health & Human Services the court once again made
clear that Althen does not lessen the ultimate burden of
proof on a petitioner to show actual causation by a pre-
ponderance of the evidence. In Cloer, the court character-
ized Althen as setting forth “three pleading requirements
for a non-Table injury petition,” Cloer, 654 F.3d at 1333
n.4, and it noted that the Althen “pleading burden is, of
course, lower than the preponderance burden that must
be met in order to receive compensation.” Id. at 1331 n.3.
Thus, by characterizing the Althen factors as “pleading
requirements,” and emphasizing that a petitioner must
ultimately satisfy the preponderance burden in order to
obtain an award of compensation, Cloer supports the
decision of the special master and the Court of Federal
Claims in this case, which applied the preponderance test
to the issue of causation, and not a lesser standard as
urged by Ms. Hibbard.

C

Ms. Hibbard’s final argument is that the evidence in
this case points so decidedly in her favor that the special
master’s conclusion that “[a] preponderance of the evi-
dence supports a finding that Ms. Hibbard does not have
autonomic neuropathy” is arbitrary and capricious.
Based on the evidence of record and the factual findings
the special master made following the two-day eviden-
tiary hearing, we reject Ms. Hibbard’s contention that the
special master’s decision denying compensation was so
plainly contrary to the evidence that it must be reversed
even under the uniquely deferential arbitrary and capri-
cious standard of review.

The special master found that Ms. Hibbard has POTS
but concluded that she failed to show that her POTS was
HIBBARD v. HHS 20

caused by autonomic neuropathy. He based that conclu-
sion on the fact that the various objective tests for auto-
nomic neuropathy that were conducted in Ms. Hibbard’s
case were all negative. Dr. Chaudhry summarized the
results of the objective testing for autonomic neuropathy
as follows: Except for the tests confirming that Ms.
Hibbard has POTS, the remaining tests for autonomic
neuropathy in the sympathetic nervous system—tests for
orthostatic hypotension, skin sympathetic response,
Valsalva maneuver, catecholamine levels, vasomotor
function, and sweating abnormalities—were all normal.
The tests for abnormalities in the parasympathetic nerv-
ous system were likewise normal, except for one test that
produced borderline results but on subsequent testing
returned to normal. As the special master summarized,
apart from the fact that she suffers from POTS, “there are
no signs that Ms. Hibbard has autonomic neuropathy.”

The special master accepted the experts’ testimony
that the Mayo Clinic study indicated that approximately
50 percent of all POTS patients have a limited form of
autonomic neuropathy. He further found, however, that
the evidence of record did not suggest that Ms. Hibbard
was among the half of POTS patients with autonomic
neuropathy. As the special master explained, “Ms.
Hibbard did not have other problems that people who
have POTS associated with an autonomic neuropathy
have. For example, Ms. Hibbard did not have low blood
pressure when standing, heart rate variation with deep
breathing, sweating abnormalities, or an abnormal skin
sympathetic test.” Many of the POTS patients in the
Mayo Clinic study had other indicators of autonomic
neuropathy. For example, the Mayo Clinic paper reported
that approximately half the patients in the study who
were tested for sudomotor denervation tested positive for
that condition, which is a sign of autonomic neuropathy.
21 HIBBARD v. HHS

By contrast, Ms. Hibbard tested negative on tests for
sudomotor denervation, as well as on all the other objec-
tive tests for autonomic neuropathy that were performed
on her. In light of the fact that Ms. Hibbard, unlike many
of the patients in the Mayo Clinic study, did not have
objective signs of autonomic neuropathy, the special
master was not plainly wrong in finding that she was not
shown to be among the 50 percent of POTS patients
whose condition, according to the Mayo Clinic study, was
caused by autonomic neuropathy.3

In addition to relying on the Mayo Clinic study, Ms.
Hibbard looks for support to the reports of several of her
treating physicians who, she argues, “suspected she
suffered an autonomic neuropathy that caused her dy-
sautonomia and POTS.” The special master reviewed the
numerous medical reports in the record and found that
while two of her treating physicians concluded that Ms.
Hibbard had autonomic neuropathy, several others,
including experts on Guillain Barré Syndrome and auto-
nomic dysfunction, did not. For example, Dr. Gorson
concluded from his examination and testing that auto-
nomic neuropathy was “a possibility,” but he stated that
he was “hesitant to confirm autonomic neuropathy with-
out more objective data to support such entity.” Dr.
Gorson recommended additional testing “to confirm an
autonomic element to her disorder.” And following the

3 Dr. Chaudhry noted that a consistent pattern of
orthostatic hypotension without a corresponding rise in
heart rate is a common sign of autonomic neuropathy. He
stated that although Ms. Hibbard showed reduced blood
pressure upon standing in some instances, that syndrome
was not consistent and therefore was not a sign of auto-
nomic neuropathy. Dr. Morgan, Ms. Hibbard’s expert,
agreed that the reduction in her blood pressure observed
on several occasions was not significant.
HIBBARD v. HHS 22

recommended testing, Dr. Freeman found that it re-
mained “unclear” the “extent to which autonomic dysfunc-
tion is contributing to her symptoms.”

Other physicians likewise had doubts about auto-
nomic neuropathy as a diagnosis. Two of her treating
physicians suggested that she might have vestibular
migraines, the diagnosis that Dr. Chaudhry regarded as
most consistent with her symptoms. Another suggested
that she might have a mitochondrial disorder. A fourth
stated that he was “suspicious that some of these symp-
toms could be psychosomatic in origin, given the extensive
negative work-up.” And a fifth concluded that “the cause
of her symptoms remains unclear. I don’t see anything
pathologic on exam and her work-up in the past has been
extensive and unremarkable.” In view of the array of
different opinions among Ms. Hibbard’s examining and
treating physicians as to the cause or causes of her symp-
toms, it was not arbitrary and capricious for the special
master to conclude from the medical evidence, including
the medical records of her physicians, that “the evidence
weighs in favor of a finding that Ms. Hibbard did not have
autonomic neuropathy.”4

Finally, Ms. Hibbard invokes the testimony of the two
experts in this case. While her own expert stated that it
was his medical opinion that she had autonomic neuropa-

4 Several of the physicians’ notes on which Ms.
Hibbard relies appear to be simply repeating Dr. Novak’s
initial diagnosis of autonomic neuropathy rather than
reflecting any additional testing or independent diagnos-
tic work. Dr. Novak’s original diagnosis, moreover, ap-
pears to be based, at least in part, on his conclusion that
“Autonomic testing by Dr. Freeman showed . . . autonomic
neuropathy,” when in fact, Dr. Freeman did not conclude
from his group’s testing that Ms. Hibbard had autonomic
neuropathy.
23 HIBBARD v. HHS

thy, the respondent’s expert, Dr. Chaudhry, disagreed.
Dr. Chaudhry agreed with the report prepared by Drs.
Gibbons and Freeman that Ms. Hibbard has POTS, and
he agreed with their statement that POTS, although a
non-specific finding, “has been associated with mild or
early autonomic neuropathy.” Ms. Hibbard relies on that
statement as supporting her claim. In fact, however, that
statement merely reaffirmed that some POTS patients
have a limited form of autonomic neuropathy, a proposi-
tion that was undisputed. As Dr. Chaudhry explained at
length in his testimony, he concluded that Ms. Hibbard’s
POTS did not point to autonomic neuropathy. He based
his opinion that Ms. Hibbard did not have autonomic
neuropathy largely on the fact that the specific tests of
Ms. Hibbard’s autonomic nervous system returned normal
results. In addition, he testified that a limited form of
autonomic neuropathy of the sort that Dr. Morgan be-
lieved was present in Ms. Hibbard’s case would not ex-
plain the large number and range of symptoms that she
reported. The special master reached the same conclusion
as Dr. Chaudhry, and for the same reasons. Thus, con-
trary to Ms. Hibbard’s contention, Dr. Chaudhry’s testi-
mony does not provide any support for her claim. Instead,
his testimony constitutes substantial evidence in support
of the special master’s decision.

In sum, considering the limited nature of our statu-
tory role in reviewing factual determinations by special
masters in Vaccine Act cases, we cannot conclude that the
contrary evidence in this case is so compelling that we
must reverse the special master’s finding that Ms.
Hibbard has not shown that she suffers from autonomic
neuropathy. The special master’s finding is “based on
evidence in the record that [is] not wholly implausible,”
Cedillo, 617 F.3d at 1338, and the special master has
articulated a rational basis for his decision, Hines, 940
HIBBARD v. HHS 24

F.2d at 1528. Because, as we have noted, a finding of
autonomic neuropathy is critical to Ms. Hibbard’s theory
of causation, we hold that the special master’s finding on
that issue is fatal to Ms. Hibbard’s petition for compensa-
tion under the Vaccine Act.

AFFIRMED
 United States Court of Appeals
for the Federal Circuit
__________________________

JENNIFER HIBBARD,
Petitioner-Appellant,

v.
SECRETARY OF HEALTH AND HUMAN
SERVICES,
Respondent-Appellee.
__________________________

2012-5007
__________________________

Appeal from the United States Court of Federal
Claims in case no. 07-VV-446, Judge Thomas C. Wheeler.
__________________________

O’MALLEY, Circuit Judge, dissenting.

For the reasons explained in my concurrence in
Lombardi v. Secretary of Heath & Human Services, 656
F.3d 1343, 1356 (Fed. Cir. 2011), I continue to question
whether our decision in Broekelschen v. Secretary of
Health & Human Services, 618 F.3d 1339 (Fed.Cir.2010)
represents an appropriate extension of our prior holdings.
I do not dissent here on those grounds, however, or
merely to repeat those concerns. I dissent here because
the Special Master, and now the majority, incorrectly
apply Broekelschen to this case and, in doing so, further
erode what is left of this court's precedential holding in
Althen v. Secretary of Health & Human Services, 418 F.3d
HIBBARD v. HHS 2

1274 (Fed.Cir.2005). If this court wishes to abandon the
burden shifting framework Althen describes—and thereby
increase the hurdles Vaccine Act Claimants must over-
come—it should do so expressly and en banc. Instead, we
have condemned Althen to a tortured end by continuing to
endorse Special Masters’ concerted efforts to narrow its
application. I can not endorse such a cause, particularly
on the record here.

Ms. Hibbard’s case presents what should have been a
straightforward application of Althen, where once Ms.
Hibbard put forward a prima facie showing of causation,
the burden should have shifted to the respondent to
establish an alternative cause for her injury. As ex-
plained below, that is not the methodology the Special
Master employed in finding against Ms. Hibbard on her
Vaccine Act claim and is not the methodology to which the
majority now defers, however. Putting questions of
methodology aside, moreover, I believe the Special Mas-
ter’s finding that Ms. Hibbard did not suffer from an
autonomic neuropathy to be arbitrary and capricious.

I.

In Althen, this court explained that a claimant seek-
ing compensation for an off-Table injury must show that
the “vaccination caused her malady.” 418 F.3d at 1278.
Specifically, the court set forth the following three-part
test for causation:

[The petitioner's] burden is to show by preponder-
ant evidence that the vaccination brought about
her injury by providing: (1) a medical theory caus-
ally connecting the vaccination and the injury; (2)
a logical sequence of cause and effect showing that
the vaccination was the reason for the injury; and
3 HIBBARD v. HHS

(3) a showing of a proximate temporal relation-
ship between vaccination and injury.

Id. By broadly defining what constitutes sufficient pre-
ponderant evidence of causation, this framework repre-
sents a balance between providing compensation to an
injured claimant and permitting the government an
opportunity to demonstrate that the claimant's injury is
due to factors unrelated to the vaccine. Id. Because Ms.
Hibbard established a prima facie case for causation, the
burden should have shifted to the government to identify
an alternative, more likely, cause of Ms. Hibbard’s dy-
sautonomia.

In Broekelschen, the court addressed a scenario in
which the parties contested the existence and nature of
claimant’s injury. 618 F.3d at 1343. Specifically, the
parties disputed whether Dr. Broekelschen, the peti-
tioner, suffered from transverse myelitis or anterior
spinal artery syndrome. Id. While the two different
injuries are associated with the symptoms presented by
Dr. Broekelschen, the underlying cause of each injury is
materially different, and it was undisputed that only
transverse myelitis is arguably related to the flu vaccine.
Id. at 1346. Therefore, “the question of causation turn[ed]
on which injury Dr. Broekelschen suffered . . . [and] it was
appropriate in this case for the special master to first
determine which injury was best supported by the evi-
dence presented in the record before applying the Althen
test . . . .” Id. (emphasis added). The majority here finds
similarity between Ms. Hibbard’s claim and that made in
Broekelschen and sanctions the Broekelschen approach,
claiming “it was not error for the special master to focus
first on whether she actually had the injury that she
claims was caused by the vaccine before addressing the
HIBBARD v. HHS 4

question whether the vaccine actually caused that injury
in her case.” Majority at 16.

But no such dispute exists with respect to the injury
claimed by Ms. Hibbard. The majority’s analysis, like the
Special Master’s, focuses entirely on questions of causa-
tion rather than injury. All parties—and the Special
Master and court below—agree that Ms. Hibbard suffers
from dysautonomia. They differ only with respect to the
cause of the dysautonomia. Ms. Hibbard, and her expert,
Dr. Thomas Morgan, contend that the flu vaccine caused
her to suffer postural orthostatic tachycardia syndrome
(“POTS”), a limited form of autonomic neuropathy, which
manifested itself as dysautonomia. The respondent, and
its expert, Dr. Vinay Chaudhry, argue that Ms. Hibbard
cannot prove by a preponderance of the evidence that she
suffered an autonomic neuropathy, and, therefore, can not
confirm the cause of her dysautonomia. The respondent
notes that other possible causes of dysautonomia exist,
but makes no effort to connect any of the alternative
causes to Ms. Hibbard. Specifically, Dr. Chaudhry testi-
fied that he does not know the cause of Ms. Hibbard’s
dysautonomia. Unlike the “unusual” case in Broekel-
schen, where “the exact injury and its nature—
inflammatory response or vascular event—is in dispute,
and, more importantly, the causation question turns on
the determination of the injury,” no alternative theory of
causation was presented here and no alternative injury or
diagnoses other than dysautonomia is in play. Broekel-
schen, 618 F.3d at 1349.

Even accepting it as true, the contention that Ms.
Hibbard’s autonomic neuropathy “was a necessary com-
ponent of her theory of vaccine-induced injury” does not
give license to either the Special Master, or this court, to
sidestep the inquiry that we have endorsed in Althen.
5 HIBBARD v. HHS

The majority inappropriately conflates an element within
the medical causation theory with the injury itself, and it
is exactly this focus on causation that Althen’s burden
shifting approach was designed to prevent. The danger of
permitting a Special Master to circumvent Althen is
apparent on this record. By characterizing his determina-
tion with respect to causation as a predicate factual
finding, the Special Master effectively avoided both the
appropriate burden of proof and the relevant standard of
review.

The majority is correct that Ms. Hibbard has not pre-
sented definitive confirmation that she suffered an auto-
nomic neuropathy, or that the flu vaccine caused her
dysautonomia, but that is not what Althen or the Vaccine
Act asks of a petitioner. See Althen, 418 F.3d at 1279-
1280. As Althen explains, a petitioner makes his or her
prima facie case by satisfying a three part test—namely
showing a medical theory causally connecting the vacci-
nation and the injury, a logical sequence of cause and
effect that the vaccination was the reason for the injury,
and a proximate temporal relationship between vaccina-
tion and injury—before returning the burden to the
respondent to show causation by factors unrelated to the
vaccine. Id. If the respondent then fails to meet that
burden by a preponderance of the evidence, the petitioner
has, under the Althen framework, necessarily made a
proper showing of causation. Id. No further showing by
the petitioner is necessary. Requiring that a petitioner
show actual causation by a preponderance of the evidence
not only eliminates the burden shifting mechanism con-
templated by Althen but also renders meaningless the
words “theory” and “logical sequence.” Simply put, noth-
ing in Althen—nor in the Vaccine Act itself—requires
showing actual causation by a preponderance of the
HIBBARD v. HHS 6

evidence; satisfaction of the three prongs is sufficient
absent rebuttal by the government.

It is undisputed that, on this record, the failure to
place the burden on the government to establish an
alternative cause for Ms. Hibbard’s injury was determina-
tive; the government proffered evidence of none. The
failure here to apply correctly the test set forth in Althen,
and the unwarranted extension of Broekelschen to this
very different factual scenario, is legal error requiring
reversal of the Special Master’s determination.

II.

Even accepting the majority’s decision to endorse the
Special Master’s extension of Broekelschen well beyond its
facts, I would still reverse the Special Master’s determi-
nation, finding it to be arbitrary and capricious on the
evidence presented. We review factual findings of the
Special Master with a high level of deference, but those
findings must reflect a consideration of the relevant
evidence of record, not be wholly implausible, and articu-
late a rational basis for the conclusion reached. See, e.g.,
Cedillo v. Sec’y of Health & Human Servs., 617 F.3d 1328,
1338 (Fed. Cir. 2010); Hines v. Sec’y of the Dep’t of Health
& Human Servs., 940 F.2d 1518, 1528 (Fed. Cir. 1991). I
cannot agree that the Special Master’s conclusion that
Ms. Hibbard did not suffer an autonomic neuropathy is
plausible.

For example, the record demonstrates that Ms.
Hibbard received multiple diagnoses of autonomic neu-
ropathy from her treating physicians. As the majority
recognizes, after an evaluation in 2004, neurologist Dr.
Louis Caplan concluded that Ms. Hibbard had “a postin-
fectious neuopathy with autonomic features.” Majority at
7 HIBBARD v. HHS

5. Testing by Dr. Christopher Gibbons and Dr. Roy
Freeman resulted in an abnormal result that led to a
diagnosis of POTS. Majority at 5. Specifically, the test-
ing found “evidence of an exaggerated postural tachycar-
dia . . . [which] has been associated with a mild or early
autonomic neuropathy . . . .” A neurological examination
by Dr. Russel Chin in 2005 noted these abnormal results
and the previous diagnosis of POTS and autonomic neu-
ropathy. While Dr. Chin was unable to confirm the prior
diagnosis, he did state that many of the other possible
causes for her symptoms had been ruled out. And in
2007, Dr. Peter Novak, concluded that the results of his
evaluation of Ms. Hibbard are suggestive of an autonomic
neuropathy.

The Special Master, however, rejected this record evi-
dence as inconclusive by noting that other doctors have
“refrain[ed]” from making a diagnosis of autonomic neu-
ropathy. He complains that one of the other treating
physicians only identified autonomic neuropathy as a
“possibility” and that he was “hesitant to confirm” it. And
he further relies on an evaluation, from a doctor who
performed later testing, stating that it was “unclear” the
extent to which autonomic dysfunction was contributing to
her systems. These equivocal statements do not, how-
ever, justify the conclusion that Ms. Hibbard does not
have an autonomic neuropathy, especially when there is
little indication that a conclusive diagnosis of autonomic
neuropathy is generally given. In fact, it is only Dr.
Chaudhry—and, by extension, the Special Master—who
has reached this absolute conclusion.

The so called “objective tests” similarly provide little
support for the Special Master’s determination that Ms.
Hibbard does not have an autonomic neuropathy. As the
majority notes, the Special Master relied “on the fact that
HIBBARD v. HHS 8

the various objective tests for autonomic neuropathy that
were conducted in Ms. Hibbard’s case were all negative.”
Majority at 20. But this determination misrepresents the
significance of the tests, statements made by Ms.
Hibbard’s expert, and statements made by the respon-
dent’s expert. In fact, the majority acknowledges a sen-
tence later that not all of Ms. Hibbard’s test results were
normal. Id. The Special Master ignored these abnormal
test results, because, in his words, “Dr. Morgan agreed
that Ms. Hibbard did not have any objective signs for a
neuropathy.” Dr. Morgan does not, however, make the
concessions that the Special Master attributes to him. He
testified that he agrees that the tests performed had
“mostly” normal results—excluding the abnormal re-
sults—but that statement does not support the Special
Master’s leap to “no objective signs.” Dr. Morgan did
testify that he agrees that Dr. Chaudhry’s report states
that there are no objective signs of Ms. Hibbard having a
peripheral neuropathy. But in the question and answer
immediately following that statement, Dr. Morgan clari-
fied that he believes Ms. Hibbard has a case of autonomic
neuropathy without peripheral involvement.

The Special Master, moreover, applied an unwar-
ranted significance to those results. Nowhere does Dr.
Chaudhry opine that the objective tests are conclusive for
diagnosing an autonomic neuropathy. In fact, all evi-
dence points to the fact that the tests do not reliably
disprove the existence of autonomic neuropathy, despite
the fact that they offer “objective” outputs. Dr. Chaudhry
admitted that there is a possibility Ms. Hibbard has mild
neuropathy, failed to provide any alternative diagnosis for
Ms. Hibbard’s POTS or dysautonomia, and testified that
he actually had ruled out many of the alternative causes
for Ms. Hibbard’s POTS. Dr. Morgan’s testimony on this
topic is enlightening:
9 HIBBARD v. HHS

Q: And, Doctor, having employed that method, you
indicated are there other diseases associated with
it, in Ms. Hibbard's case were there any other
causes found for her dysautonomia?

A: There were not.

***

Q: What tests did they do in May to rule out dy-
sautonomia?

A: Tests don't make the diagnosis. All right?
Tests help support a diagnosis. If it was that easy,
you don't need doctors, just plug it into the com-
puter, spit it out and you've got your diagnosis. So,
there were no tests and they wouldn't necessarily
drive the diagnosis, but, more importantly, there's
probably no need to do those tests.

A169; A246.

The error in over-reliance on these objective tests is
amply seen in the Special Master’s—and the majority’s—
treatment of the Mayo Clinic study introduced by Ms.
Hibbard. In that study, researchers concluded that a
neuropathic basis existed for at least half of the cases of
POTS they examined, which supported their initial postu-
late that POTS is a limited autonomic neuropathy. Here,
all parties agree that Ms. Hibbard has POTS. They
disagree only as to the significance of this finding with
respect to a conclusion of autonomic neuropathy. Ms.
Hibbard contends that the Mayo Clinic study shows that
her POTS is indicative of an autonomic neuropathy. The
Special Master, in contrast, agreed with the respondent’s
view that Ms. Hibbard’s predominantly normal test
HIBBARD v. HHS 10

results support a conclusion that she is not in the ap-
proximately 50 percent of all POTS patients that have a
limited form of autonomic neuropathy.

The majority’s acceptance of the respondent’s position
suffers from the same flaw as the Special Master’s before
it. Ms. Hibbard does not dispute that causes other than
neuropathy exist for POTS, but, as Dr. Chaudhry testi-
fied, no other cause for Ms. Hibbard’s POTS was identi-
fied and many of the possible alternative causes were
expressly ruled out. As such, the likelihood that Ms.
Hibbard’s POTS was caused by a neuropathy is actually
significantly greater than the 50 percent likelihood trum-
peted by the majority. More importantly, the lack of
abnormal test results provides almost no support for the
conclusion that Ms. Hibbard is not part of the 50 percent
of people whose autonomic neuropathy caused their
POTS. In the Mayo Clinic study, 90.8 percent of the
participants exhibited predominantly normal results in
response to tests similar to the ones performed on Ms.
Hibbard. Therefore, even assuming all of the patients
that had abnormal results suffered from autonomic
neuropathy, over 80 percent of the participants in the
study identified as having POTS and autonomic neuropa-
thy would have had to exhibit predominantly normal
results to the “objective” tests relied on so heavily by the
special master.

I agree that a Special Master’s factual findings are ac-
corded deference, but in light of the great evidence to the
contrary, I must conclude that the Special Master’s de-
termination that Ms. Hibbard did not suffer an autonomic
neuropathy was arbitrary and capricious.
11 HIBBARD v. HHS

III.

Based on the record before us, I think it clear that Ms.
Hibbard has put forward a prima facie case under Althen
that the administered flu vaccine caused her dysautono-
mia. The Special Master characterized Dr. Morgan’s
medical theory as “poorly supported,” but the respondent
appears to present no real challenge to Ms. Hibbard’s
satisfaction of the first Althen prong. Rather, the respon-
dent focused on whether Ms. Hibbard affirmatively estab-
lished that she suffered from one of the links in the causal
chain leading to her injury. Regardless of the respon-
dent’s attack on the adequacy of the evidence of auto-
nomic neuropathy, the respondent cannot dispute that the
evidence establishes a logical sequence of cause and
effect. I therefore see no legitimate dispute as to Ms.
Hibbard’s satisfaction of the second Althen prong. Fi-
nally, as the majority notes, the respondent expressly
conceded that Ms. Hibbard’s claim satisfies the temporal
prong. Majority at 11. Having presented a prima facie
case of causation, the burden, in accordance with Althen,
appropriately shifts to the respondent to demonstrate a
likely alternative cause for Ms. Hibbard’s injury.1 As Ms.
Hibbard contends, the respondent failed to put forward
any alternative cause, let alone a likely one. Dr.
Chaudhry’s testimony fails to back any alternative theory
that would explain Ms. Hibbard’s injury. As such, rever-
sal of the determination of the Special Master and entry
of judgment for the petitioner is appropriate.

1 If the majority and the Special Master were cor-
rect that, in addition to the Althen showing, a Vaccine Act
claimant must also separately establish each link in the
causal chain by a preponderance of the evidence, there
would be no burden left to shift back to the government.
HIBBARD v. HHS 12

Separately, and in addition, I would find that the Spe-
cial Master erred in determining that Ms. Hibbard did not
establish that she suffered an autonomic neuropathy by a
preponderance of the evidence. This error standing alone
warrants reversal.