HEMATOLOGICAL ABNORMALITIES IN SHWACHMAN-DIAMOND SYNDROME

We have analysed the haematological parameters in 21 patients with Shw achman-Diamond syndrome (SDS) seen over a 25-year period at our instit ution. Neutropenia, although present in all patients, was intermittent in two-thirds, constant in the rest and was associated with impaired chemotaxis in all of those patients tested. Fetal haemoglobin (HbF) wa s elevated in 80% of the patients at some stage, and anaemia and throm bocytopenia was documented in 66% and 24% respectively. Bone marrow sa mples were taken in over half of the patients. Myelodysplastic syndrom e (MDS) developed in seven (33%) patients, five of whom had acquired c lonal structural chromosome abnormalities in their bone marrows. In fi ve of the patients with RADS (24%) transformation to acute myeloid leu kaemia occurred. Like other constitutional bone marrow failure syndrom es, SDS has a predilection to leukaemic transformation hitherto assume d to be in the region of 5-10%. The data presented here suggest that t his figure probably represents an underestimate. Shwachman-Diamond syn drome is an interesting model of leukaemia development and greater und erstanding of the clinical spectrum of this rare disorder should produ ce further insights into its pathobiology.