Radhika Agarwal v. HHS - Tdap, autoimmune limbic encephalitis (ALE) with the associated biomarker of GAD antibodies, and the residual effects of cognitive deficits and intractable epilepsy (2020)

On February 8, 2016, Saurabh and Mukta Agarwal filed a petition on behalf of their daughter, Radhika Agarwal, alleging that the Tdap and meningococcal (Menactra) vaccines administered on August 5, 2013, caused her to develop autoimmune limbic encephalitis (ALE) with GAD antibodies, resulting in cognitive deficits and intractable epilepsy. The respondent recommended against compensation, contesting both the diagnosis and causation.

Prior to vaccination, Radhika was healthy with normal development. Three days after vaccination, she developed a fever, followed by lethargy.

On August 12, 2013, she experienced vomiting and passed out, and later that night, EMS responded to her being incoherent and postictal. She was taken to Advocate Sherman Hospital on August 13, 2013, for altered mental status and possible seizures, then transferred to Advocate Lutheran General Hospital's pediatric intensive care unit.

There, she experienced tonic-clonic seizures, status epilepticus, and was placed in a pentobarbital-induced coma. Initial tests showed elevated anti-microsomal, anti-thyroglobulin, and serum GAD antibodies, with later CSF analysis revealing elevated protein and cells.

An MRI on August 23, 2013, showed abnormalities in the hippocampal formations and amygdala, suspicious for limbic encephalitis of autoimmune etiology. She received extensive treatment, including plasmapheresis, IVIG, rituximab, and cyclophosphamide.

Radhika was transferred to Lurie Children's Hospital on August 29, 2013, with a diagnosis of anti-GAD related autoimmune encephalitis. Her condition persisted with refractory seizures and psychiatric symptoms after emerging from the coma.

She was discharged home on March 17, 2014, requiring ongoing care and experiencing limitations in daily activities, attention, ambulation, and safety awareness. Subsequent evaluations, including by Mayo Clinic physicians in 2016, favored autoimmune limbic encephalitis.

Petitioners' expert, Dr. A.H.M.

Mahbubul Huq, opined that the vaccines triggered an autoimmune process involving inflammation and T-cell activation, with GAD antibodies serving as a biomarker for T-cell mediated limbic tissue damage. Respondent's expert, Dr.

Michael Kruer, argued that Radhika's condition was more consistent with febrile infection-related epilepsy syndrome (FIRES) due to her lack of response to early immunotherapy, MRI evolution, and negative CSF GAD antibodies. Special Master Thomas L.

Gowen found that the evidence supported a diagnosis of autoimmune limbic encephalitis associated with GAD antibodies, rejecting the FIRES diagnosis. He concluded that the petitioners met all three prongs of the Althen test for causation, finding a medically acceptable temporal relationship and no alternative cause.

On July 15, 2021, a damages award was issued. The award included $2,022,234.46 for life care expenses, lost future earnings, and pain and suffering, payable to Radhika's estate.

An additional $84,643.06 was awarded for past unreimbursable expenses to her parents. A payment of $812,257.97 was allocated to satisfy the Illinois Medicaid lien.

The award also included an annuity for future life-care items, with growth rates of 4% for non-medical and 5% for medical items. Petitioners were represented by Ronald C.

Homer and Meredith Daniels of Conway, Homer, P.C.