Systemic lupus erythematosus occurring in a patient with Niemann–Pick type B disease

Niemann–Pick disease is an inherited lipid storage disorder caused by the deficiency of acid sphingomyelinase, which results in accumulation of sphingomyelin within cells of several organs and consequent tissue damage. The broad clinical spectrum of this disorder may overlap with that of systemic lupus erythematosus, hindering differential diagnosis. Herein, we report the case of a patient affected by Niemann–Pick type B disease intertwined with clinical and serological features of systemic lupus erythematosus. Two novel mutations in the SMPD1 gene were found in compound heterozygosity: p.A36V and IVS2 + 8 T > G.