Castaneda v. Secretary of Health and Human Services, 15-1066

Background

Petitioner Kathy Castaneda filed a Vaccine Program petition (2015; amended 2016) alleging her son N.A.C. developed Pediatric Acute-Onset Neuropsychiatric Syndrome (PANS) after vaccinations on September 26, 2012 (Pentacel, MMR, Prevnar 13).
Symptoms (tics, repetitive/OCD-like behaviors, emotional lability, head‑banging, aggression) were reported to begin ~30 hours after vaccination; ER admission occurred October 9, 2012 and neurology evaluation followed October 15, 2012.
Treating neurologist documented tic-like movements and stated he did not think the movements were vaccine-related; multiple later records note Tourette syndrome, tics, ADHD, OCD, and possible autism spectrum features.
Petitioner’s expert (Dr. Kiki Chang) diagnosed PANS and proposed an inflammatory/cytokine-based mechanism by which vaccination could rapidly (hours–days) trigger basal ganglia inflammation and PANS; Respondent’s expert (Dr. Donald Gilbert) conceded an acute neuropsychiatric syndrome but rejected vaccine causation and emphasized alternative explanations and lack of mechanistic or diagnostic evidence of immune activation.
The Special Master found N.A.C. met PANS diagnostic criteria but concluded Petitioner failed to meet the Althen three‑prong causation standard (insufficient reliable theory, lack of proof of a logical causal sequence, and medically‑unsupported timing) and dismissed the petition (Decision filed May 18, 2020).

Issues

Issue	Plaintiff's Argument	Defendant's Argument	Held
Can vaccination cause PANS (Althen prong 1)?	Vaccines can trigger cytokine/inflammatory cascades that cross the blood‑brain barrier and selectively inflame basal ganglia, causing PANS (Dr. Chang).	No reliable evidence that vaccine‑induced cytokine responses produce targeted basal ganglia inflammation causing PANS; mechanism speculative (Dr. Gilbert).	Held: No — petitioner failed to prove a reliable, preponderant medical theory that vaccines cause PANS.
Did the vaccines cause N.A.C.’s PANS (Althen prong 2)?	Temporal proximity and expert opinion link the vaccination to N.A.C.’s acute onset and PANS presentation.	Treating records do not attribute symptoms to vaccines; no diagnostic/immune testing shows post‑vaccine immune activation.	Held: No — petitioner failed to show a logical sequence of cause and effect tied to the vaccinations.
Was onset temporally appropriate for causation (Althen prong 3)?	Cytokine response can occur within hours, so onset ~30 hours post‑vaccination is consistent with petitioner’s inflammatory theory.	One‑day onset is implausibly rapid for the proposed vaccine‑driven mechanisms; timing not medically established.	Held: No — petitioner did not establish a medically‑acceptable timeframe connecting vaccination to onset.
Are pre‑existing conditions (tics/autism) relevant to diagnosis and causation?	Pre‑existing mild symptoms do not rule out PANS; acute emergence of OCD/secondary symptoms supports PANS triggered by vaccination.	Video and records show pre‑existing tics and possible ASD which provide alternative explanations for symptoms and susceptibility to tics/OCD.	Held: N.A.C. meets PANS criteria, but pre‑existing tics/possible ASD undermine the causal link to vaccination and are not dispositive of PANS causation.

Key Cases Cited

Althen v. Sec'y of Health & Human Servs., 418 F.3d 1274 (Fed. Cir. 2005) (establishes three‑prong causation test for off‑Table Vaccine Act claims)
Capizzano v. Sec'y of Health & Human Servs., 440 F.3d 1317 (Fed. Cir. 2006) (discusses Table injuries and causation presumptions)
Moberly v. Sec'y of Health & Human Servs., 592 F.3d 1315 (Fed. Cir. 2010) (preponderance standard and expert reliability in vaccine cases)
Boatmon v. Sec'y of Health & Human Servs., 941 F.3d 1351 (Fed. Cir. 2019) (special masters may require indicia of reliability for expert assertions)
Andreu v. Sec'y of Health & Human Servs., 569 F.3d 1367 (Fed. Cir. 2009) (permitting theory without published literature but requiring reliable indicia)
Knudsen v. Sec'y of Health & Human Servs., 35 F.3d 543 (Fed. Cir. 1994) (expert testimony must be sound and reliable)
Cucuras v. Sec'y of Health & Human Servs., 993 F.2d 1525 (Fed. Cir. 1993) (weight accorded to contemporaneous medical records)
Daubert v. Merrell Dow Pharm., 509 U.S. 579 (U.S. 1993) (factors for assessing scientific reliability)