A baby girl with TBX1 haploinsufficiency who died after elective cardiac repair surgery due to suspected enteroviral meningitis

Abstract

IntroductionTBX1 haploinsufficiency is an inborn error of immunity with the phenotype of DiGeorge Syndrome. DiGeorge Syndrome has variable immunodeficiency associated with grade of thymic hypoplasia ranging from mild with no infections to severe requiring thymus implant. Enterovirus is an example of an opportunistic infection that can be fatal in these patients. Case PresentationA 1 year old girl with TBX1 haploinsufficiency complicated by Tetralogy of Fallot, pulmonary atresia, high arched palate, and vesicovaginal fistula presented for elective cardiac repair surgery from another country due to failure to thrive and cyanosis. She had no prior infectious history but was on sulfamethoxazole-trimethoprim for prophylaxis. She was asymptomatic with a negative COVID test but no other infectious studies performed. Immediately postoperatively, she was febrile and nasal respiratory viral panel was positive for rhinovirus/enterovirus with increased procalcitonin and leukocytosis with left shift. She decompensated with multi-organ failure and cardiac arrest on postoperative day two. She was cannulated to veno-arterial extracorporeal membrane oxygenation (ECMO). Pre-operatively, she had a normal absolute lymphocyte count. No thymus tissue was observed in surgery. She had profound CD3 lymphopenia to 130 cells/cmm when critically ill. Enteroviral meningitis was suspected as no infectious, cardiac, or other pathology could be identified causing decompensation. Enteroviral serum polymerase chain reaction (PCR) test was negative while lumbar puncture deferred due to clinical status. She was treated with immunoglobulin. Offlabel investigational drug pocapavir was considered but deferred to patient’s irreversible neurological status. The patient was disconnected from ECMO and expired. DiscussionThough we cannot confirm that this patient had enteroviral meningitis, invasive enteroviral infections are associated with elevated transaminases, coagulopathy, and seizures all present in our patient. There has also been reported negative serum enteroviral PCR but positive CSF enteroviral PCR in an immunodeficient patient. Additionally, this case highlights the importance of immunologic evaluation in patients with DiGeorge Syndrome and questions if asymptomatic viral screening for viruses like enterovirus should be considered pre-operatively in patients with inborn errors of immunity. This case highlights potential treatment options for invasive enteroviral infections in patients with inborn errors of immunity: high dose immunoglobulin, fluoxetine, and pocapavir.