Development of Varicella Zoster Encephalitis Following Live Vaccination in a Patient with Ataxia Telangiectasia

This case describes a 4-year-old female with a history of ataxia telangiectasia (AT) with compound heterozygous variants (ATM; c.1339C>T (p.Arg447*) and c.829G>T (p.Glu277*)) who received measles, mumps, rubella (MMR) live vaccine and varicella zoster virus (VZV) vaccination in error in the setting of moving and change of pediatrician. After receiving live vaccines, she was referred to the immunology clinic. She had no concerning symptoms and was started on IgG replacement for low IgG level (474 mg/dL). One month later, the patient developed an itchy rash and fever, diagnosed as a coxsackie infection. Four months following vaccination, the patient presented to her hematologist for scheduled evaluation and was noted to have facial palsy and sent to the emergency room for evaluation. Over the preceding few weeks, her parents had started to notice some slurring of words and her walking had become unstable with frequent falls and increasingly difficult time ambulating. Emergency room evaluation was significant for tachycardia without fever, right-sided facial droop with conjunctival injection, diffuse weakness, and healing skin lesions. Lab findings at the time showed stable lymphopenia. A lumbar puncture was performed with positive VZV PCR. Peripheral blood was also positive for VZV PCR. MRI brain was performed which showed nonspecific global inflammation which was consistent with VZV encephalitis given infectious studies. While inpatient, she was treated with intravenous acyclovir, and intravenous immunoglobulin (IVIG) replacement was started under the direction of neurology, infectious diseases, and immunology services. Her neurologic condition improved with antiviral treatment. With infectious workup, Epstein Barr virus (EBV) PCR was also positive in the blood. She was discharged and received 6 months of high-dose acyclovir therapy. 6 months following her admission for VZV encephalitis, the patient was diagnosed with EBV-associated lymphoma and is currently undergoing treatment. This case prompted reflection in terms of the prevention of accidental/contraindicated vaccinations and a discussion on the management of live vaccination administration to a patient with ataxia telangiectasia. The recommendation following vaccination is to monitor clinically for the development of infectious sequelae. For this particular patient, the lesions diagnosed as coxsackie viral infection were more likely acute disseminated VZV infection.