Resumen:
Low-affinity immunoglobulin gamma Fc region receptor III-B (Fc?RIIIB) deficiency is present in ?0·05% of the general population. Among our patients, Fc?RIIIB deficiency was less frequent in those with immune-system disorders (one of 1815 patients, 0·05%) than in those with blood disorders (nine of 2147 patients, 0·42%, P = 0·023): mainly primary immune thrombocytopenia (4·34%), therapy related myeloid neoplasms (1·16%) and myelodysplastic syndrome with excess blasts (1·28%). Four of the nine (44·4%) patients with blood disorders were diagnosed with or quickly evolved to acute myeloid leukaemia (AML), suggesting that Fc?RIIIB deficiency could be an adverse prognostic factor for progression to AML that should be confirmed in large multicentre studies.