Sea blue histiocytosis. A clinical cytologic and nosographic study on 23 cases.

The authors examine the main clinical, cytologic and nosographic aspects of conditions and syndromes associated with SBH on the basis of the literature data (about 40 cases) and 23 personal ones. It is necessary to distinguish between three nosological conditions of SBH: hereditary disease, hereditary asymptomatic, acquired per se asymptomatic. From the clinical viewpoint less a half of all SBH cases are hereditary and present a syndrome based on splenomegaly, periodic hemorrhagic diathesis (due to variable thrombocytopenia), not rarely associated with hepatomegaly and lung or nervous system changes (often eyes are involved). There is also a second SBH hereditary form, vary rare and clinically different from the former, determined by deficiency of plasma-lecitin-cholesterol acyltransferase. The peculiar features of SBH are discussed by means of optical, cytochemical, electron microscopical investigations which point out the polymorphous aspect of these "famished" macrophages. The material stored by SBH is heterogeneous and the enzymatic defect of the most frequent form still remains obscure. The presence of SBH in different haemopathies has an analogous significance as Gaucher's cells found outside Gaucher's disease. It is impossible today to deny the existence of two well-identified SBHS.