Entitlement – Addison’s Disease caused by TDaP Vaccine
Simmons v. HHS, (Fed. Cl. Spec. Mstr. Oct. 30, 2015) (Millman, SM)
In this unusual case, both experts agreed that Petitioner suffered an immediate hypersensitivity reaction to TDaP, an anaphylactoid-like episode. The experts disagreed whether Petitioner’s continuing immune symptoms, culminating in Addison’s disease, were a sequela of that initial reaction.
The immediate allergic reaction to Tdap resulted from Petitioner’s IgA sensitivity to casein, a milk product used in production of the tetanus toxoid portion of Tdap vaccine. This immediate allergic reaction led, over time, to more symptoms indicative of an adverse immune process, including hair loss, repetitive rashes, weakness, diarrhea, and ultimately to failure of his adrenal glands to produce cortisol and aldosterone, similar to Addison’s disease, an autoimmune disorder.
Although Petitioner was unable to give a specific biological mechanism explaining how his immune response to Tdap vaccine led to Addison’s disease, the court noted that this puzzlement fits exactly into the Federal Circuit’s statement in Althen that we are dealing in a field bereft of complete and direct proof of how vaccines affect the human body.
The Court was impressed by the continuity of allergic and immune symptoms petitioner had immediately following receipt of Tdap vaccine, noting that he had been immunologically abnormal since the vaccine and his health had been severely damaged.
The Court noted that the issue, in this case, was whether an adverse reaction to a vaccination must adhere to strict categories such as allergy, immune-mediated, and/or auto-immune, or whether someone’s adverse reaction can be composed of components of each category. In that regard, the Court held that a blurring of the distinctions among the three categories of adverse reactions does not preclude a finding of entitlement to damages.
In finding entitlement to compensation, the Court thought it reasonable to connect petitioner’s entire immunologic reaction to his initial adverse response, although the specific biological mechanism(s) causing Petitioner’s perduring reaction to the Tdap vaccine were unknown. The court further observed that the testimony of both immunologic experts revealed the paucity of knowledge in the medical field of describing what mechanism can explain immune-mediated/hypersensitivity reactions.