Enfermedad de Niemann-Pick tipo B. Estudio de tres casos y revisión de la literatura

Objective: To describe the course of type B Niemann- Pick disease (ENP-B) by following the evolution of three pediatric patients. Methods: Three patients, two of them male, age be- tween two and eleven years, with type B Niemann-Pick disease were evaluated periodically by physic exam and laboratory: hematologic indices, lipid profile, hepatic function tests; Radiologic studies: chest X-ray, abdominal ultrasound, cranial computed tomography, echocardiogram. Histologic exams: hepatic biopsy, bone marrow aspirate. We also obtained information on intercurrent pathologies. Results: Symptoms started ~3 years (2-5 years) and the diagnosis was made at the age of ~5 years 3 months (2-11 years), based on clinical findings suggestive of ENP-B; on foam cells in bone marrow aspirate in the three patients, hepatic biopsy in two; acid sphingomyelinase determination in three. The clinical manifestations were: hepatosplenomegaly in three; neurologic involvement in two; bone involvement in one; pulmonary involvement in two; liver involvement in three; affected hematological indices in three; lipid abnormalities in three; cardiac involvement in one; ocular manifestations in one; growth retardation in three. In none of the families were detected consan- guinity nor endogamy. Conclusions: This study shows the multisystemic involvement and the clinic variability in the type B Niemann-Pick disease, which is characterized es- sentially by hepatosplenomegaly with the possibility of development of liver dysfunction. Patients have a progressive hypersplenism. They present an athero- genic lipid profile. A gradual pulmonary affection, and other systemic manifestations are observed. The diagnosis confirmation, requires the determination of acid sphyngomyelinase. To date, there are no useful biomarkers to evaluate the disease activity. Enzyme replacement therapy is still on research.