K.L. v. HHS - HPV, partial-onset epilepsy, seizures, migraine headaches, and alleged neurologic sequelae (2017)
Case summary [AI summaries can sometimes make mistakes]
On May 11, 2012, K.L. filed a petition under the National Vaccine Injury Compensation Program, alleging that the human papillomavirus (HPV) vaccine, Gardasil, caused partial-onset epilepsy, seizures, migraine headaches, and related neurologic sequelae. K.L. was born on March 25, 1993.
Her medical history included recurrent ear infections, anxiety disorder, reading difficulties, and a vasovagal attack. She also had a family history of seizures.
K.L. received three doses of Gardasil: May 18, 2009, August 18, 2009, and February 9, 2010. No complications were noted after the first two doses.
On February 11, 2010, two days after her third Gardasil dose, K.L. experienced a seizure characterized by twitching, foaming at the mouth, and cyanosis. She was taken to the emergency room and subsequently transferred to Vermont Children's Hospital.
Initial evaluations, including a head CT, blood count, and EKG, were normal. At the hospital, her condition was attributed to a combination of factors, including a mild upper respiratory infection, over-the-counter medications, and the recent HPV vaccination.
Her MRI and lumbar puncture were normal, but an EEG showed an impaired arousal mechanism. Her primary care physician noted the etiology was unclear, possibly related to the vaccine or decongestants, or new-onset epilepsy.
K.L. experienced another seizure on February 27, 2010, and was prescribed Keppra. She was later evaluated by Dr.
Louisa Kalsner, who noted the temporal proximity of the first seizure to the Gardasil dose and increased her Keppra dosage. Dr.
Annapurna Poduri, a neurologist and epileptologist, reviewed K.L.'s case and, after a normal MRI, diagnosed juvenile-onset idiopathic partial-onset epilepsy, not vaccine-related epilepsy. K.L. remained seizure-free on Keppra until an attempt to reduce the dosage in 2013 led to recurrence, which was controlled by increasing the dose.
She also developed migraines and gastrointestinal issues. Petitioner's expert, neurologist Dr.
Beatrice Engstrand, proposed that the HPV vaccine triggered an immune response and cytokine signaling, leading to brain hyperexcitability and seizures. She initially focused on interleukin-1 beta but later broadened her theory to general cytokine signaling.
Dr. Engstrand relied on adverse event surveillance and literature concerning autoimmune reactions and seizures, but conceded she could not point to specific testing from K.L.'s hospitalization that confirmed an autoimmune reaction.
Respondent's expert, pediatric neurologist Dr. Shlomo Shinnar, opined that K.L. had idiopathic epilepsy, emphasizing her normal test results, lack of fever, family history, and seizure control with medication.
He also cited epidemiological studies showing no increased neurological risk from the HPV vaccine. Special Master Brian H.
Corcoran denied entitlement on March 17, 2017. He found Dr.
Engstrand lacked immunology expertise for her theory and that her cited literature was not persuasive. He found Dr.
Shinnar's explanation and respondent's evidence more credible, noting the lack of evidence for an autoimmune process and the temporal proximity alone being insufficient. Judge Marian Blank Horn affirmed the denial on August 8, 2017, finding the Special Master's decision was not arbitrary or capricious.
No compensation was awarded.
Theory of causation
Petitioner K.L. received Gardasil vaccinations on May 18, 2009, August 18, 2009, and February 9, 2010. She alleged that the third dose, administered at age 16.88, caused partial-onset epilepsy, seizures, migraine headaches, and neurologic sequelae, with the first major seizure occurring on February 11, 2010. Petitioner's expert, Dr. Beatrice Engstrand, proposed a theory that the HPV vaccine induced an immune response and cytokine signaling, leading to brain hyperexcitability and afebrile seizures. She initially identified interleukin-1 beta as the mechanism but later broadened it to general cytokine signaling, relying on adverse event literature and studies on autoimmune reactions and seizures. Respondent's expert, Dr. Shlomo Shinnar, diagnosed idiopathic epilepsy, citing K.L.'s normal test results, lack of fever, family history, and seizure control with medication, and presented epidemiological data suggesting no link between HPV vaccine and neurological events. Treating epileptologist Dr. Annapurna Poduri also diagnosed idiopathic epilepsy. Special Master Brian H. Corcoran denied entitlement on March 17, 2017, finding Dr. Engstrand's theory lacked sufficient scientific basis and expertise, and that respondent's evidence was more persuasive. Judge Marian Blank Horn affirmed the denial on August 8, 2017. Petitioner's counsel was Paul S. Dannenberg, and respondent's counsel was Robert P. Coleman. No compensation was awarded.