Case: 21-1866 Document: 38 Page: 1 Filed: 05/20/2022
United States Court of Appeals
for the Federal Circuit
______________________
T.S., BY AND THROUGH HIS PARENTS, GERMAIN
SANCHEZ, JENNIFER SANCHEZ,
Petitioners-Appellants
v.
SECRETARY OF HEALTH AND HUMAN
SERVICES,
Respondent-Appellee
______________________
2021-1866
______________________
Appeal from the United States Court of Federal Claims
in No. 1:11-vv-00685-PEC, Judge Patricia E. Campbell-
Smith.
______________________
Decided: May 20, 2022
______________________
LISA A. ROQUEMORE, Law Office of Lisa A. Roquemore,
Rancho Santa Margarita, CA, argued for petitioners-appel-
lants.
HEATHER LYNN PEARLMAN, Vaccine/Torts Branch, Civil
Division, United States Department of Justice, Washing-
ton, DC, argued for respondent-appellee. Also represented
by BRIAN M. BOYNTON, C. SALVATORE D'ALESSIO, JENNIFER
LEIGH REYNAUD.
______________________
Case: 21-1866 Document: 38 Page: 2 Filed: 05/20/2022
2 T.S. v. HHS
Before MOORE, Chief Judge, BRYSON and DYK, Circuit
Judges.
Opinion for the court filed by Chief Judge MOORE.
Dissenting opinion filed by Circuit Judge BRYSON.
MOORE, Chief Judge.
Trystan Sanchez appeals a decision of the United
States Court of Federal Claims that sustained a special
master’s decision denying Trystan compensation under the
Vaccine Act. Sanchez v. HHS, 152 Fed. Cl. 782, 784 (2021).
For the following reasons, we reverse and remand.
BACKGROUND
I
On February 5, 2009, Trystan Sanchez, then a six-
month-old baby, had a well-child check with Dr. Philip
Brown. Dr. Brown gave Trystan multiple vaccines, includ-
ing the DTaP-HepB-IPV vaccine. Hours later, Trystan de-
veloped a fever of 102.2°F and was crying a loud, high-
pitched cry, as if he was in pain. Trystan was inconsolable
and developed a hot lump on his left thigh. Trystan’s fever
fluctuated over the next few days.
On February 15, 2009, Trystan’s fever returned, and he
became congested. The next night, his fever rose to
103.2°F, and he cried loudly in a high pitch. When
Trystan’s father was able to calm him, he would startle
awake as if he could not breathe. Trystan kicked and
jerked as if he did not want to be held. Trystan also exhib-
ited arm contortions, holding his arms stiffly behind his
back. When his father would try to straighten his arm, it
would snap back.
On February 17, 2009, Trystan’s mother took him to
urgent care where he saw Jonathan Luna, a physician as-
sistant. Mrs. Sanchez later testified that she told Mr. Luna
Case: 21-1866 Document: 38 Page: 3 Filed: 05/20/2022
T.S. v. HHS 3
about the arm contortions, but Mr. Luna’s notes do not
mention them. Mr. Luna diagnosed Trystan with a “com-
mon cold” and “viral syndrome.”
According to his family’s testimony, Trystan’s arm con-
tortions continued during the period immediately following
February 16. Trystan’s father, mother, and paternal
grandmother all testified that his arm contortions occurred
often multiple times a day during this period. J.A. 630–33;
J.A. 518; J.A. 530–31, 578; J.A. 466, 476. See also J.A. 596–
97 (Trystan’s maternal grandmother testifying that she
witnessed an arm contortion in late February 2009).
At his one-year exam in August 2009, Micaela Marin-
Tucker, a physician assistant, noted Trystan was develop-
mentally behind and could not stand, crawl, grasp, hold his
head up while sitting, or attempt to move his lower extrem-
ities. His mother stated that she noticed a change in his
development approximately two to three months earlier.
At this appointment, Trystan received his next round of
vaccinations. Mr. Sanchez testified that shortly thereafter,
his arm contortions returned.
Trystan proceeded to have muscle spasms, develop-
mental delays, seizures, dystonia, 1 and other neurologic is-
sues for the next few years. For years, the precise nature
of Trystan’s illness eluded his doctors. Trystan was even-
tually diagnosed with Leigh’s syndrome in late 2014.
Leigh’s syndrome is a severe neurological disorder that of-
ten presents in the first year of life, is characterized by pro-
gressive loss of mental and movement abilities, and
typically results in death within “a couple years.” J.A. 40.
1Dystonia is characterized by involuntary muscle
contractions that cause repetitive movements or abnormal
postures and is caused by neurological abnormality or dam-
age. J.A. 2816.
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4 T.S. v. HHS
Genetic testing showed that Trystan has two disease-caus-
ing mutations associated with Leigh’s syndrome.
II
In October 2011, Mr. and Mrs. Sanchez petitioned for
compensation under the Vaccine Act, 42 U.S.C. § 300aa–1
et seq. Despite all the contrary family testimony, and with-
out discussing that testimony, a special master found that
Trystan did not have arm contortions until months after
his February 2009 vaccination. J.A. 686. However, in his
later decision denying compensation, the special master re-
versed course, crediting Mr. Sanchez’s testimony that
Trystan had arm contortions on February 16. J.A. 2297
(“[O]n February 1[6], 2009, . . . [h]is arms contorted and he
was jerking around.”). But the special master also found
that those contortions were a symptom of Trystan’s cold,
not Leigh’s syndrome, and that the first sign of Trystan’s
Leigh’s syndrome, the start of “a neurologic decline,” likely
did not occur “until May 1, 2009, at the earliest.” J.A. 106.
And because of this multi-month delay in the development
of symptoms, the special master found it more likely than
not that the vaccine was not a substantial factor in
Trystan’s Leigh’s syndrome. The Claims Court affirmed.
The Sanchezes appealed to this court, and we vacated
and remanded, holding that the record did not support the
special master’s finding that Trystan’s arm contortions
were a symptom of a cold. Sanchez v. HHS, 809 F. App’x
843, 852–53 (Fed. Cir. 2020) (non-precedential). In re-
manding, we instructed the special master to (1) address if
Trystan’s arm contortions on February 16, 2009 were evi-
dence of a seizure or dystonia and thus a sign of a neuro-
logic injury; (2) revisit causation and provide a complete
analysis of all prongs of the causation analysis; and (3) ad-
dress if Trystan’s genetic mutations were the sole substan-
tial cause of his Leigh’s syndrome, including if the timing
and severity of Trystan’s Leigh’s syndrome would have
been the same absent the vaccine. Id. at 853–54.
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T.S. v. HHS 5
On remand, the special master ordered supplemental
status reports, directed the parties to provide updated
medical records, and allowed the parties to supplement
their expert reports. Based in part on that new evidence,
the special master found that Trystan’s arm contortions on
February 16 were not a neurologic abnormality caused by
his vaccination or manifestations of a neurological disor-
der. Again, the special master denied compensation, this
time on two grounds: (1) Trystan did not experience neuro-
logic deterioration until many weeks after his February
2009 vaccination and (2) the Secretary established that
Trystan’s two genetic mutations solely caused his Leigh’s
syndrome. The Claims Court sustained the special mas-
ter’s decision. Mr. and Mrs. Sanchez appeal. We have ju-
risdiction under 28 U.S.C. § 1295(a)(3).
DISCUSSION
In Vaccine Act cases, we review the Claims Court’s de-
cisions de novo, “applying the same standard of review that
court applied in reviewing the special master’s decision.”
Milik v. HHS, 822 F.3d 1367, 1375–76 (Fed. Cir. 2016). Ac-
cordingly, we review the special master’s legal conclusions
de novo and his findings of fact under an arbitrary-and-ca-
pricious standard. Althen v. HHS, 418 F.3d 1274, 1277–78
(Fed. Cir. 2005); Porter v. HHS, 663 F.3d 1242, 1249 (Fed.
Cir. 2011).
To prove causation in fact, 2 a claimant must show: (1) a
medical theory causally linking the vaccine and the injury;
(2) a logical sequence of cause and effect showing the vac-
cine was the reason for the injury; and (3) a proximate tem-
poral relationship between vaccination and injury. Althen,
418 F.3d at 1278. If the claimant meets this burden, he is
2Trystan is required to show causation in fact be-
cause his claim is “off table,” i.e., a claim not listed in 42
U.S.C. § 300aa-14.
Case: 21-1866 Document: 38 Page: 6 Filed: 05/20/2022
6 T.S. v. HHS
entitled to compensation unless the government demon-
strates that the injury was caused by factors unrelated to
the vaccine. 42 U.S.C. § 300aa–13(a)(1)(B).
I
The special master’s determination that Trystan failed
to prove causation in fact turned entirely on his finding
that Trystan’s February 16 arm contortions were a one-off
event. Based on that finding, the special master concluded
that the contortions were not a symptom of a neurologic
injury, that “Trystan did not start a neurologic decline un-
til May 1, 2009, at the earliest” (months after his February
2009 vaccination), and, thus, that Trystan failed to satisfy
Althen prongs two and three. That finding, however, was
arbitrary and capricious. On the record before us, the only
reasonable conclusion is that Trystan’s arm contortions
continued after February 16 and were a symptom of a neu-
rologic injury. Accordingly, Trystan satisfied Althen
prongs two and three and established causation in fact. 3
There is no dispute that Trystan has Leigh’s syndrome
and that neurodegeneration is a result of Leigh’s syn-
drome. J.A. 40. There is likewise no dispute that dystonia
(like Trystan’s arm contortions) or seizures can be a mani-
festation of Leigh’s syndrome. J.A. 96. Trystan was vac-
cinated February 5, 2009 and had a cold on February 16,
2009. The special master found, based exclusively on
Trystan’s family’s testimony, that Trystan had arm contor-
tions (a seizure-like experience) on February 16, 2009,
shortly after his vaccination. J.A. 2297. The special mas-
ter also found, based entirely on family testimony, that
Trystan was experiencing arm contortions in August 2009
consistent with Leigh’s syndrome: “Some information
about Trystan’s health before the second set of vaccinations
comes from his family’s testimony about his behavior
3 That Trystan satisfied prong one is not in dispute.
Case: 21-1866 Document: 38 Page: 7 Filed: 05/20/2022
T.S. v. HHS 7
during the baby shower on August 9, 2009. This testimony
credibly established that Trystan lacked muscle tone and
was having arm contortions.” J.A. 108 (emphasis added).
There is no dispute that by August of 2009 his significant
developmental delays associated with his Leigh’s syn-
drome were observed and documented. J.A. 687; Oral Arg.
at 30:20–31, 34:28–35:05.
Despite the February arm contortions, the special mas-
ter found “that Trystan’s neurodegeneration began around
May 1, 2009” rather than in February. J.A. 107. The spe-
cial master’s entire conclusion hinged upon his finding
that: “there appears to be no evidence that between Febru-
ary 17, 2009, and at least May 1, 2009, that Trystan suf-
fered a seizure or stroke-like episode. Trystan did have
arm contortions of February 16, 2009. But, that episode
was short-lived, singular, and did not signify a neurologic
injury due to vaccination.” J.A. 102. The special master
explained, “it seems unlikely that Trystan would experi-
ence an episode of dystonia that is caused by an injury in
his basal ganglia one time in February 2009 and not expe-
rience any other motor problems for months.” J.A. 98. The
government’s expert, Dr. Raymond, testified that “[i]f
Trystan were having arm contortions in February 2009 due
to Leigh[’s] syndrome and basal ganglia injury, they would
have been persistent.” J.A. 98.
This entire case turns on a single fact finding by the
special master. The special master found the family’s tes-
timony that Trystan had arm contortions on February 16,
2009 credible. The special master also found that Trystan
had arm contortions beginning August 9, 2009 (and contin-
uing thereafter), again based entirely on the family’s testi-
mony, which he expressly found to be credible. However,
the special master rejected the testimony from the same
family members that the arm contortions continued
throughout the relevant period from February 16 to May 1.
And he did so with no particular explanation as to how the
former claims regarding arm contortions (February 16 and
Case: 21-1866 Document: 38 Page: 8 Filed: 05/20/2022
8 T.S. v. HHS
August 9) were credible and the identical testimony from
the identical witness that there were additional arm con-
tortions between February and May was somehow not
credible. Such an inconsistent, unfounded, and entirely
unexplained fact finding is arbitrary and capricious.
The relevant record evidence shows that Trystan’s con-
tortions persisted after February 16. Mr. Sanchez testified
that Trystan continued to have arm contortions multiple
times a day in the days, weeks, and months following Feb-
ruary 16. J.A. 630–33. Mrs. Sanchez similarly testified
that Trystan continued to have arm contortions in the
months following the February 16 contortions—sometimes
“five to ten times a day.” J.A. 518, accord J.A. 530–31, J.A.
578. Trystan’s paternal grandmother testified that
Trystan had arm contortions “approximately three times a
day” from February to August. J.A. 466; J.A. 476.
Trystan’s maternal grandmother testified that approxi-
mately two to three days after February 16, she witnessed
Trystan contorting his arm when she was attempting to
put him in his car seat and she was unable to place his arm
behind the seat buckle. J.A. 596–97. And Trystan’s aunt
testified that when she saw him at a family event in March
2009, he was “so hard [and] so stiff.” J.A. 495. None of this
testimony was rebutted. Moreover, medical records from
November 12, 2009, and August 2, 2010, albeit non-con-
temporaneous with the events in question, corroborate the
family’s testimony. J.A. 308, 362. There was no contrary
record evidence.
The only reasons the special master articulated for dis-
crediting the family’s testimony were that it conflicted with
“[t]he absence of notation [of arm contortions] in any of the
contemporaneous medical records” and the general asser-
tion that “memories dim with the passage of time.” J.A.
683. Given the record in this case, such a conclusion is ar-
bitrary and capricious.
Case: 21-1866 Document: 38 Page: 9 Filed: 05/20/2022
T.S. v. HHS 9
To be sure, the special master was not required to
credit this testimony simply because there is no contrary
evidence in the record. See, e.g., Anderson v. City of Besse-
mer City, N.C., 470 U.S. 564, 575 (1985) (“[A witness’] story
itself may be so internally inconsistent or implausible on
its face that a reasonable factfinder would not credit it.”);
cf. Trade Well Int’l v. United Cent. Bank, 825 F.3d 854, 861
(7th Cir. 2016) (“A district court need not have contrary ev-
idence to discredit a witness.”). However, the special mas-
ter here provided no sound basis for discrediting the
extensive family testimony regarding the relevant time pe-
riod between February and May where he expressly cred-
ited much of this same testimony at other times. 4 And
contrary to the Secretary’s arguments, see Oral Arg. at
19:20–20:20, 22:45–28:40, 32:25–34:00, no contemporane-
ous medical record mentioned the February 16 contor-
tions. 5 These fact findings cannot be reconciled.
4 The notes from the visit with Ms. Marin-Tucker in
August 2009 indicating that Ms. Sanchez only noticed de-
velopmental changes approximately 2–3 months earlier do
not contradict the substantial family testimony establish-
ing that Trystan’s arm contortions occurred in an even ear-
lier period.
5 Our court explained in Kirby v. HHS, 997 F.3d
1378 (Fed. Cir. 2021), “As the Claims Court has recognized,
physicians may enter information incorrectly and ‘typically
record only a fraction of all that occurs.’” Id. at 1383 (quot-
ing Shapiro v. HHS, 101 Fed. Cl. 523, 538 (2011)). We
agreed with the Claims Court that “the absence of a refer-
ence to a condition or circumstance is much less significant
than a reference which negates the existence of the condi-
tion or circumstance.” Id. In this case, none of the early
medical records mention the arm contortions, but the spe-
cial master nonetheless found them to have begun on Feb-
ruary 16, 2009.
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10 T.S. v. HHS
This is an unusual case where a remand is unnecessary
because here the special master’s finding of arm contor-
tions on February 16, 2009 (and his associated credibility
determination) is law of the case. The government did not
challenge this fact finding in the prior appeal. The earlier
findings stand and the special master’s findings that there
were no arm contortions in the relevant period between
February and May cannot be reconciled with his earlier de-
terminations.
Given the record and the prior findings, there is no ba-
sis to reject the evidence that Trystan was experiencing
arm contortions throughout the relevant period. It neces-
sarily follows that Trystan’s contortions were a sign of a
neurologic injury because the Secretary’s expert witness
and the special master acknowledged as much. The Secre-
tary’s expert witness, Dr. Raymond, gave unrebutted testi-
mony that persistent arm contortions are symptomatic of a
neurologic injury. J.A. 98 (“If Trystan were having arm
contortions in February 2009 due to Leigh[’s] syndrome
and basal ganglia injury, they would have been persistent
and obvious.”). And the special master relied entirely upon
the alleged lack of persistent contortions to find that the
contortions were not a sign of neurologic injury. Id. (“[I]t
seems unlikely that Trystan would experience an episode
of dystonia that is caused by an injury in his basal ganglia
one time in February 2009 and not experience any other
motor problems for months.”). The record provides no al-
ternative explanation for persistent contortions nor did the
government argue for any.
Because those contortions began within two weeks of
his vaccinations, Trystan has shown a logical chain of
cause and effect between his vaccination and his neuro-
degeneration. See J.A. 75 (“[I]f . . . Trystan developed neu-
rodegeneration within a short time (approximately two
weeks) after the vaccination, then a ‘logical’ conclusion
might be that the vaccination caused the
Case: 21-1866 Document: 38 Page: 11 Filed: 05/20/2022
T.S. v. HHS 11
neurodegeneration.”). Therefore, Trystan has satisfied his
burden of showing Althen prongs 2 and 3.
II
As Trystan has met his burden, he is entitled to com-
pensation unless the Secretary establishes the injury was
due to factors unrelated to the vaccine. 42 U.S.C. § 300aa–
13(a)(1)(B). In that regard, the special master found that
Trystan’s genetic mutations were the sole substantial
cause of his Leigh’s syndrome.
There is no evidence, however, that Trystan’s muta-
tions would have resulted in the same progression and se-
verity of his Leigh’s syndrome absent the vaccine. The
special master merely cited a reference describing a child
with similar mutations who developed Leigh’s syndrome
and concluded Trystan’s Leigh’s syndrome would manifest
the same way. J.A. 129–34. At the outset, a single example
does not establish the typical progression of a disease and
is not “sufficient to disprove a medical theory that a vaccine
can cause aggravation in some patients.” Sharpe v. HHS
964 F.3d 1072, 1084 (Fed. Cir. 2020). Moreover, the cited
reference provides no information on how the subject’s dis-
ease progressed after manifestation, and the subject’s
Leigh’s syndrome presented at nine months of age. J.A.
126–27. So, at best, the reference merely shows Trystan
would have developed Leigh’s syndrome at nine months of
age absent the vaccine. That says nothing about what
caused Trystan’s Leigh’s syndrome to manifest at six
months of age or to progress the way it did. Thus, the gov-
ernment did not meet its burden to establish Trystan’s
Leigh’s syndrome was the result of factors unrelated to the
vaccine.
CONCLUSION
In sum, Trystan has proven causation in fact, and the
government has failed to overcome that showing. Accord-
ingly, Trystan is entitled to compensation under the
Case: 21-1866 Document: 38 Page: 12 Filed: 05/20/2022
12 T.S. v. HHS
Vaccine Act. We reverse the decision denying compensa-
tion and remand to the special master for the sole issue of
damages.
REVERSED AND REMANDED
COSTS
Costs to Trystan.
Case: 21-1866 Document: 38 Page: 13 Filed: 05/20/2022
United States Court of Appeals
for the Federal Circuit
______________________
T.S., BY AND THROUGH HIS PARENTS, GERMAIN
SANCHEZ, JENNIFER SANCHEZ,
Petitioners-Appellants
v.
SECRETARY OF HEALTH AND HUMAN
SERVICES,
Respondent-Appellee
______________________
2021-1866
______________________
Appeal from the United States Court of Federal Claims
in No. 1:11-vv-00685-PEC, Judge Patricia E. Campbell-
Smith.
BRYSON, Circuit Judge, dissenting.
The National Childhood Vaccine Injury Act empowers
the special masters who adjudicate claims under the Act to
exercise broad discretion in evaluating the merits of those
claims. Congress’s intent to vest such discretion in the spe-
cial masters is reflected in our standard of review, which
empowers the Court of Federal Claims—and by extension,
this court—to overturn a special master’s decision only
when the decision is “arbitrary, capricious, an abuse of dis-
cretion, or otherwise not in accordance with law.” 42
U.S.C. §§ 300aa-12(e)(2)(B), 300aa-12(f); see also Munn v.
Sec’y of Health & Hum. Servs., 970 F.2d 863, 870 (Fed. Cir.
1992) (noting that the arbitrary-or-capricious standard is
Case: 21-1866 Document: 38 Page: 14 Filed: 05/20/2022
2 T.S. v. HHS
“well understood to be the most deferential possible”). The
court today overturns the special master’s factual findings
as unsupported. I believe that there is sufficient evidence
in the record to support the special master’s findings, and
that those findings are not arbitrary or capricious.
In vaccine injury cases, “[w]e do not reweigh the factual
evidence, assess whether the special master correctly eval-
uated the evidence, or examine the probative value of the
evidence or the credibility of the witnesses—these are all
matters within the purview of the fact finder.” Porter v.
Sec’y of Health & Hum. Servs., 663 F.3d 1242, 1249 (Fed.
Cir. 2011). If the special master’s findings are “based on
evidence in the record that was not wholly implausible, we
are compelled to uphold that finding as not being arbitrary
or capricious.” Lampe v. Sec’y of Health & Hum. Servs.,
219 F.3d 1357, 1363 (Fed. Cir. 2000). Most importantly,
we do not “second guess” the special master’s conclusions,
especially where “the medical evidence of causation is in
dispute.” Cedillo v. Sec’y of Health & Hum. Servs., 617 F.3d
1328, 1338 (Fed. Cir. 2010). In light of those principles, the
majority opinion does not give the special master’s decision
the deference it is due.
I
At the outset, it is important to note that Trystan
Sanchez was born with two genetic mutations that caused
him to develop Leigh’s syndrome, a mitochondrial disorder
affecting the central nervous system. In infants with those
mutations, Leigh’s syndrome typically manifests following
a stressor, often a viral infection, within the first 12 months
of life. J.A. 2309. Both parties’ experts agreed that the
mutations predisposed Trystan to developing Leigh’s syn-
drome, but the Sanchezes argued that the stressor that
caused the onset of Leigh’s syndrome was the series of vac-
cinations that Trystan received on February 5, 2009. J.A.
47, 118. The question presented by this case is whether
Trystan’s vaccinations triggered the onset of his Leigh’s
Case: 21-1866 Document: 38 Page: 15 Filed: 05/20/2022
T.S. v. HHS 3
syndrome, or whether that condition, to which he was ge-
netically predisposed, was triggered by another stressor,
such as one of the periodic colds that he suffered between
February and June of 2009.
The focus of the majority’s analysis is on whether the
evidence showed that Trystan manifested signs of a neuro-
logical injury within days of his February 5, 2009, vaccina-
tions. The evidence showed (and it is not disputed) that on
February 16, 2009, Trystan was suffering from a cold.
Trystan’s father testified that while he was trying to com-
fort Trystan that evening, Trystan contorted his arms and
arched his back in an unusual manner. The question that
was the subject of much attention during the evidentiary
proceedings was whether Trystan’s arm contortions on the
evening of February 16, 2009, were indicative of neurolog-
ical injury or were consistent with the cold from which he
was suffering at the time.
A
Dr. Gerald Raymond, one of the government’s experts,
addressed the relationship between the arm contortions
and Trystan’s cold. In his report, which was in evidence in
this case, Dr. Raymond stated that “[t]he events in Febru-
ary around the time of the six month evaluation are more
consistent with a viral [upper respiratory infection] and not
myoclonic jerks.” J.A. 1101. In a supplemental report, Dr.
Raymond added that Trystan’s arm contortions were “con-
sistent with an uncomfortably ill child who is tired and
does not want to be held.” J.A. 2737. The special master
found Dr. Raymond to be credible and his statements about
Trystan’s actions on the night of February 16, 2009, to be
persuasive evidence that Trystan’s behavior on that night
was not indicative of a neurological injury.
The special master’s finding that Trystan’s arm contor-
tions were an isolated event and not evidence of the onset
of Leigh’s syndrome is further supported by other evidence
in the record. First, after seeing Trystan for a cold on April
Case: 21-1866 Document: 38 Page: 16 Filed: 05/20/2022
4 T.S. v. HHS
29, 2009, pediatrician Nabil A. Seleem noted that Trystan
“exhibited no neurological symptoms.” J.A. 220. Second,
at a visit on May 13, 2009, another pediatrician, Philip S.
Brown, similarly did not report any neurological symp-
toms. J.A. 686–87. Third, at an appointment with physi-
cian’s assistant Micaela Marin-Tucker in August 2009,
Trystan’s mother reported that “she noticed a change in
[Trystan’s] development about 2–3 months ago,” i.e., in
May or June of 2009. J.A. 222. Notably, that statement in
Ms. Marin-Tucker’s report is inconsistent with Trystan’s
mother’s testimony at the hearing before the special mas-
ter, where she testified that Trystan’s arms contorted
“around five to ten times a day” between February 17,
2009, and April 29, 2009. J.A. 518.
In addition to those medical reports, the special master
considered Dr. Raymond’s expert opinion regarding the
likelihood that the arm contortions were a manifestation of
a neurological injury. Dr. Raymond noted that “[i]f Trystan
were having arm contortions in February 2009 due to
Leigh[’s] syndrome and basal ganglia injury, they would
have been persistent and obvious and it is expected that
his attentive parents would have brought it to the attention
of his providers as they did for his other illnesses.” J.A.
2737–38. Dr. Raymond further stated that arm contortions
behind the infant’s back manifesting dystonia would not be
possible “without appropriate myelination,” which, in his
view, would have been unlikely at six months of age. J.A.
97.
B
To be sure, there is evidence in the record that could
support a contrary conclusion, particularly the testimony
from family members regarding Trystan’s behavior during
the interval between February and May 2009. See, e.g.,
J.A. 362, 476, 518, 597, 630–33, 717. In addition, the peti-
tioners’ expert, Dr. Lawrence Steinman, testified that “arm
contortions” can be “intermittent” and “are not a
Case: 21-1866 Document: 38 Page: 17 Filed: 05/20/2022
T.S. v. HHS 5
manifestation of the common cold.” See J.A. 2813–14. But
those conflicts in the evidence were for the special master
to resolve, and the special master’s decision to credit the
evidence that pointed away from the petitioners’ theory
that Trystan’s neurological injury manifested itself shortly
after his vaccinations was not arbitrary or capricious.
Nor was it arbitrary or capricious for the special master
to credit the testimony of Trystan’s father that Trystan was
contorting his arm on the night of February 16, 2009, but
not to accept the testimony of Mr. Sanchez and other family
members that Trystan’s arm contortions continued during
the months immediately following that incident. It is well
established that a fact finder is entitled to “accept those
portions of a witness’s testimony which it considers credi-
ble and reject other portions which it finds to be improba-
ble.” See Rixey v. W. Paces Ferry Hosp., Inc., 916 F.2d 608,
616 (11th Cir. 1990); see also United States v. Boyce, 564
F.3d 911, 916 (8th Cir. 2009); United States v. Ware, 577
F.3d 442, 447 (2d Cir. 2009); United States v. Dozier, 162
F.3d 120, 125 (D.C. Cir. 1998); United States v. De Leon
Ruiz, 47 F.3d 452, 454 (1st Cir. 1995); United States v. Col-
ston, 936 F.2d 312, 315 (7th Cir. 1991); United States v.
Cueto, 628 F.2d 1273, 1275 (10th Cir. 1980); Conway v.
Chem. Leaman Tank Lines, Inc., 610 F.2d 360, 367 (5th
Cir. 1980); Carothers v. Rhay, 594 F.2d 225, 229 (9th Cir.
1979); NLRB v. Boyer Bros., 448 F.2d 555, 561 (3d Cir.
1971); People v. Mendoza-Balderama, 981 P.2d 150, 157–
58 (Colo. 1999) (collecting cases). And as this court has
previously noted, a special master’s “assessments of the
credibility of the witnesses” are “virtually unchallengeable
on appeal.” Lampe, 219 F.3d at 1362.
In particular, it was within the province of the special
master not to credit the lay testimony of the family mem-
bers where it was in tension with contemporaneous medi-
cal records, Dr. Raymond’s expert opinion, and other
evidence in the case. As to the events of February 16, 2009,
the special master credited Dr. Raymond’s assessment that
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6 T.S. v. HHS
Trystan’s behavior could be explained by the discomfort
caused by his cold. The special master found the father’s
testimony regarding the events of that night to be generally
plausible and not indicative of the onset of a neurological
injury. The special master also credited the family mem-
bers’ testimony that Trystan experienced arm contortions
in August 2009 and that those manifestations of dystonia
were accompanied by significant developmental delays.
As to the family members’ testimony that Trystan ex-
perienced continuous arm-contortion incidents between
February and May of 2009, however, the special master
found that testimony to be in conflict with other evidence
in the record. He did so in his initial decision denying com-
pensation, J.A. 2297–98, and he adhered to those findings
in his decision following the remand from this court, J.A.
99–107. In light of the record evidence, the special master’s
conclusions were reasonable. For instance, in their con-
temporaneous reports, Drs. Seleem and Brown, who saw
Trystan in late April and mid-May 2009, did not note the
presence of arm contortions or any other neurological
symptoms. Nor did their reports reflect that Trystan’s par-
ents mentioned the arm contortions.
It is true that, in general, “the absence of a reference to
a condition or circumstance is much less significant than a
reference which negates the existence of the condition or
circumstance.” Kirby v. Sec’y of Health & Hum. Servs., 997
F.3d 1378, 1383 (Fed. Cir. 2021). However, the fact that
neither doctor’s contemporaneous report makes any refer-
ence to arm contortions or any other neurological symp-
toms and that those reports did not reflect that Trystan’s
parents mentioned Trystan’s arm contortions is probative
of whether the contortions continued after the evening of
February 16, 2009. That is especially true in light of Dr.
Raymond’s testimony that arm contortions due to Leigh’s
syndrome and basal ganglia injury would have been persis-
tent and obvious, and that if Trystan were experiencing
arm contortions attributable to those conditions, his
Case: 21-1866 Document: 38 Page: 19 Filed: 05/20/2022
T.S. v. HHS 7
parents likely would have raised that issue with the pedi-
atricians during their visits in April and May 2009.
Of the evidence relied upon by the special master, the
report of Ms. Marin-Tucker regarding her interview with
Ms. Sanchez during Trystan’s pediatric visit in August
2009 is of particular significance. Ms. Marin-Tucker’s
notes reflected that Trystan’s mother said she had first
noted a change in Trystan’s development in about April or
May of 2009. That observation, which was made closer in
time to Trystan’s vaccinations than any of the family’s later
testimony, suggests that Trystan’s condition did not mani-
fest itself until well after his February 2009 vaccinations.
On the surface, the reports of other physicians who as-
sessed Trystan’s condition after August 2009 appear to cor-
roborate the family’s testimony about Trystan’s behavior in
the weeks following his February 2009 vaccinations. How-
ever, those reports regarding the events of early 2009 were
based on histories obtained from Trystan’s parents, not on
the firsthand observations of the treating physicians. See
J.A. 95, 362. For that reason, it was reasonable for the spe-
cial master not to attach independent significance to those
reports regarding the timing of the onset of Trystan’s con-
dition.
II
In summary, given the competing evidence regarding
the etiology of Trystan’s condition, it was not unreasonable
for the special master to conclude that Trystan’s Leigh’s
syndrome did not manifest itself until significantly later
than the date of his February 2009 vaccinations, and there-
fore that no causal relationship was established between
the vaccinations and the triggering of Trystan’s Leigh’s
syndrome. J.A. 117. There is ample evidence in the record
consistent with those findings. Even if we were applying a
“substantial evidence” standard of review, we would be
obliged to sustain the special master’s decision. A fortiori,
the special master’s weighing of the evidence cannot fairly
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8 T.S. v. HHS
be considered arbitrary or capricious. Moreover, nothing
in the special master’s analysis was contrary to law, and
there is no suggestion that he selectively ignored particular
evidence. The majority disagrees with the special master’s
conclusion regarding causation in this case. But that is not
enough to justify concluding that the special master’s deci-
sion was arbitrary or capricious. Accordingly, I would up-
hold the decision of the Court of Federal Claims affirming
the special master’s decision.