Haemophagocytic lymphohistiocytosis in association with granular lymphocyte proliferative disorders in early childhood: characteristic bone marrow morphology.
Mots clés
Abstrait
Five paediatric cases of haemophagocytic lymphohistiocytosis (HLH) which showed proliferation of granular atypical lymphocytoid cells in bone marrow are reported. All cases were girls aged 8 months to 4 years who had marked hepatosplenomegaly. Marker analysis on peripheral blood mononuclear cells revealed an increase in the CD3+HLADR+ subset in three cases and the CD3- CD56+ subset in one case. An Epstein-Barr virus genome was detected in three cases, and monoclonality was confirmed in two cases. A characteristic morphology of large granular lymphocytes (LGL) was identified, with elongated bizarre features that resembled horsetail-, tadpole-, cucumber- or shooting star-type configurations on the bone marrow smear. Serum concentrations of soluble interleukin-2 receptor and interferon-gamma were elevated in all cases. All five cases required multi-agent chemotherapy which resulted in two complete remission, two partial remissions and one no response. Refinement of treatment is required for these paediatric GLPD cases which probably comprise a specific high-risk subgroup among secondary HLH patients which had previously escaped notice.