ESPE Abstracts

Background: Sea-blue histiocytosis is a morphological finding that can be associated both with acquired conditions of increased cellular turnover and inborn errors of lipid metabolism.

Objective and hypotheses: To present a Chinese boy of hypertension and sea-blue histiocytosis secondary to Niemann–Pick disease type B.

Methods: Diagnosis was confirmed by the bone marrow aspiration and the specific enzyme assay of leukocytes (deficiency in sphingomyelinase activity).

Results: The 8-year and 9-month old boy was the first child of non-consanguineous parents of Chinese Han ethnicity, who presented with hepatosplenomegaly for 4 years. General physical examination showed short stature with Ht 106 cm (−5 S.D.) and abdominal distention. On systemic examination, hypertension with BP 158/119 mmHg was noted, and hepatosplenomegaly measuring 10 cm below costal margins, respectively was present. Neurological examination and respiratory function tests were normal. Chest X-rays revealed diffuse reticular pattern. The echocardiography showed a thickening (8 mm) of the interventricular septum. Ultrasonography showed a bright liver, which is usually fatty tissue. Coagulation function tests showed slightly prolonged activated partial thromboplastin time (APTT), lipid profile showed elevated LDL (3.57 mmol/l), elevated TG (2.37 mmol/l), and decreased HDL (0.54 mmol/l). Other admission laboratory data include following: white blood cell count, hemoglobin, platelet count, serum total bilirubin, aspartate aminotransferase, alanine aminotransferase, serum albumin, were all within normal ranges. Hematoxylin–eosin staining of bone marrow showed scattered foci of foamy histiocytes. May-Giemsa staining of the bone marrow smear showed multiple blue-colored granules were found in the cytoplasm of histiocytes. Histiocytes were stained blue by the Schmorl reaction. The acidic sphingomyelinase activity seen in peripheral blood leukocytes was lower (4.75 nmol/mg per h) than normal (40.29 nmol/mg per h), confirming a diagnosis of seablue histiocytosis secondary to Niemann–Pick disease.

Conclusion: We report a rare case of sea-blue histiocytosis associated with Niemann–Pick disease type B in a 8-year and 9-month old boy with hypertension.