X-linked agammaglobulinemia (XLA) is a primary immunodeficiency caused by mutations in the gene for Bruton tyrosine kinase, resulting in an increased susceptibility to a variety of infections. Vaccine-associated paralytic poliomyelitis (VAPP) is a rare adverse event of Oral Polio Vaccine (OPV) due to mutation or reversion of the vaccine virus to a more neurotropic form.
Through our case report we would like to highlight that VAPP may be a first presentation of X-linked agammaglobulinemia.
A 5 month old boy presented at our hospital with fever, irritability, generalized hypotonia and abdominal breathing fifteen days after the second dose of OPV. No previous infections before the vaccination. The initial cerebrospinal fluid examination showed pleocytosis (196mm3); lymphocytosis 95% and neutrophils 5%. The electro-diagnostic (ENG) examination of the right leg indicated remote distal axonal neuropathy of the deep peroneal nerve. No abnormalities were observed in the brain and spinal MRI. His first faecal specimen was positive for Sabin type 3 strains. Laboratory evaluation revealed low levels of IgM, IgA. CD19+B and CD20+B cells were less than 1% of the lymphocyte population. The BTK gene analysis of the patient’s DNA revealed the presence of the mutation c.[1922G>A] p.[R641H].
A negative history for recurrent infections does not exclude the presence of a primary defect in the immune system. VAPP may be the first presentation of some primary immunodeficient patients. Introduction of neonatal screening programs for some immune deficiency states, such as SCID and XLA, could help in preventing an inadvertent exposure of affected patients to OPV.