Predominant Neurologic Manifestations Seen in a Patient With a Biallelic Perforin1 Mutation (PRF1; p.R225W).

Neurological manifestations in familial hemophagocytic lymphohistiocytosis (FHL) are common, seen in up to 73% of patients in their course of disease. However, in majority of the cases central nervous system manifestations are associated with other clinical and laboratory parameters of hemophagocytic lymphohistiocytosis. We report here a case with FHL2 in whom hemophagocytic lymphohistiocytosis was a presenting manifestation which responded to specific therapy, however, there was isolated central nervous system relapse while patient was in remission and off therapy. FHL2 was confirmed on the basis of reduced perforin expression and homozygous mutation in PRF1at codon 637 in exon 3 (c.673C>T p.Arg225Trp).