Rare association Niemann-pick B syndrome and familial Fanconi syndrome

Abstract

Recent advancements in therapeutic development have led to a significant breakthrough in the treatment of acid sphingomyelinase deficiency (ASMD), with Olipudase α emerging as the first specific enzyme replacement therapy. This innovative treatment aims to replace the deficient or defective acid sphingomyelinase enzyme, offering hope for patients with this condition. We report the case of a 28-year-old male from a first-degree consanguineous family with a history of Fanconi syndrome and nephrolithiasis, hospitalized for moderate renal impairment and asthenia. Diagnostic evaluation revealed tubular proteinuria, glycosuria, hyperphosphaturia, hyperuricuria, and hypercalciuria, leading to the diagnosis of Fanconi syndrome. Additionally, the patient’s distinctive facial features, hepatosplenomegaly, hypertriglyceridemia, and thrombocytopenia prompted further investigation, culminating in the diagnosis of Niemann-Pick type B syndrome (NPBS), confirmed by biochemical and genetic studies. This case highlights the rare association of an autosomal dominant disorder (Fanconi syndrome) and an autosomal recessive disorder (NPBS) in a Maghrebian family, diagnosed late in adulthood, resulting in a significant therapeutic delay.

Keywords: Toni-Debré Fanconi syndrome; Niemann-Pick B syndrome; Renal failure