Kaylon Tipps v. HHS - Tdap, meningoencephalitis (2022)

On July 22, 2016, Kay and Cathell Tipps filed a petition for compensation under the National Vaccine Injury Compensation Program on behalf of their minor son, Kaylon Tipps. Kaylon Tipps, born May 31, 2001, received Meningococcal and Tetanus-Diphtheria-Acellular-Pertussis (Tdap) vaccines on July 24, 2013.

The petition alleged that these vaccines caused him to suffer meningitis and seizures. A two-day entitlement hearing was held on May 4-5, 2022.

Chief Special Master Brian H. Corcoran issued a decision on December 9, 2022, denying an entitlement award, finding that the petitioner had not preponderantly established that the vaccines were likely causal of his subsequent illness.

According to the fact history, Kaylon Tipps was twelve years old at the time of vaccination and had a medical history including asthma, allergies, eczema, and obesity. Sixteen days after vaccination, on August 9, 2013, he presented to an emergency room with a severe headache and blurred vision, leading to IV fluids and discharge.

Three days later, on August 12, 2013, he returned to the ER with starring, unresponsiveness, headache, vomiting, neck pain, and vision changes. Initial evaluations included a lumbar puncture showing pleocytosis, but the results were deemed unreliable due to medication interference.

He was discharged with a diagnosis of aseptic versus viral meningitis. Subsequent evaluations included a CT scan and EEG, which were normal, leading to a suspicion of partial complex seizures.

Further evaluation revealed elevated intracranial pressure and papilledema, consistent with increased intracranial pressure. Testing ruled out several viral infections.

He was diagnosed with headache, pseudotumor cerebri, and aseptic meningitis. He experienced worsening headaches and neck pain, and his vision deteriorated significantly, requiring optic nerve sheath fenestration in his right eye due to severe visual field and acuity loss.

He later underwent a similar procedure on his left eye. His diagnoses upon discharge included increased intracranial pressure, aseptic meningitis, severe papilledema, and improved vision loss.

In 2015, he was evaluated for persistently elevated inflammatory markers, but no evidence of rheumatic, autoimmune, or immunodeficiency illness was found. Additional testing ruled out masses or lymphadenopathy.

He was later evaluated for lymphoproliferative disorder, which was also ruled out. Despite improvements, he continued to suffer from regular headaches and general vision impairment, including diabetes insipidus.

At the hearing, Kaylon Tipps testified about his ongoing health issues, including partial blindness in his right eye and occasional "thundering sounds" due to increased brain pressure. His father corroborated the timeline of events and the absence of pre-existing upper respiratory infections.

Petitioner's expert neurologist, Dr. Steven Lovitt, opined that Mr.

Tipps suffered from meningoencephalitis, likely aseptic meningitis, and that the vaccinations were more likely than not the cause due to the atypical, prolonged course, severe increased intracranial pressure, and negative infectious testing, with the onset sixteen days post-vaccination being within an expected timeframe. Petitioner's immunologist, Dr.

David Axelrod, proposed a theory that the meningococcal and Tdap vaccines caused autoimmune meningoencephalitis through molecular mimicry and the production of pathogenic anti-idiotypic antibodies that could bind to nervous system components. He cited literature suggesting that vaccine components could bind to neuronal gangliosides and that anti-idiotypic antibodies could cause inflammation or damage.

Respondent's experts countered these theories. Pediatric neurologist Dr.

Elaine C. Wirrell testified that Mr.

Tipps's symptoms were most consistent with viral meningoencephalitis, not autoimmune encephalitis, citing the lack of typical autoimmune encephalitis features and inconsistent MRI findings. She noted that many cases of meningoencephalitis have an unknown etiology and that studies did not support a causal link between the Tdap vaccine and encephalopathy.

Immunologist Dr. Andrew J.

MacGinnitie argued that Petitioner's theory of anti-idiotypic antibodies causing disease lacked sufficient data, questioned the ability of vaccine toxoids to bind to neuronal tissues pathologically, and highlighted the speculative and outdated nature of the literature cited by Dr. Axelrod.

He also emphasized the difficulty antibodies would have in crossing the blood-brain barrier and the lack of evidence of such a breach in Mr. Tipps's case.

Dr. MacGinnitie concluded that Petitioner's experts failed to establish a target of autoimmunity or a cross-reactivity triggered by vaccine components.

Chief Special Master Corcoran found that Petitioner had not preponderantly established that the vaccines were likely causal. He noted that the medical records did not affirmatively identify a virus, but also found that Respondent more compellingly established the low likelihood of an autoimmune cause due to the absence of confirming test results, inconsistent MRI findings, and lack of evidence of known autoantibodies.

The Special Master found Petitioner's causation theory deficient because it relied on a novel and mostly theoretical conception of anti-idiotypic antibodies as pathogenic drivers, incorrectly assumed wild toxins would function like vaccine toxoids, and lacked sufficient evidence to establish that a pathological autoimmune process would occur even if such antibodies were produced. The Special Master also found the theory strained, as it was not evident that all forms of encephalitis are autoimmune, and the proposed mechanism was not persuasively linked to Mr.

Tipps's specific condition. The Special Master found Respondent's experts to be clearer and more persuasive in explaining the deficiencies in Petitioner's theory.

Therefore, entitlement was denied.