RESUMO
BACKGROUND: Hydranencephaly is a relatively rare but severe structural brain abnormality that often results in perinatal death. Although several factors including infection and multiple births have been reported to be associated with this birth defect, the underlying etiology is not well understood. Recently, FLVCR2 gene mutations have been implicated in a subset of hydranencephaly cases, following an autosomal recessive pattern of inheritance. CASE: We report a male infant with hydranencephaly found to have a previously unreported six amino acid deletion in one copy of the FLVCR2 gene following a pregnancy complicated by poor prenatal care and maternal cocaine use. Although our patient currently presents with developmental delays, he is showing progress and gaining some skills. CONCLUSION: We discuss the possibility of a synergistic effect between the FLVCR2 genetic mutation and environmental cocaine exposure, creating a susceptible brain, as an explanation for this infant's phenotype. This case demonstrates the potential clinical utility of testing for mutations in FLVCR2 for patients with hydranencephaly after other possible etiologies, such as congenital infection, have been reasonably eliminated. Current literature on FLVCR2 is relatively sparse; identifying additional patients with similar mutations will aid in defining the clinical significance of a gene mutation and the contribution to the etiology of hydranencephaly.