An unusual association of monoclonal gammopathy, paroxysmal nocturnal haemoglobinuria and myelodysplastic syndrome transformed into acute myeloid leukaemia: coexistence of triple clonal disorders.

An unusual association of paroxysmal nocturnal haemoglobinuria (PNH), myelodysplastic syndrome (MDS), acute myeloid leukaemia (AML) and monoclonal gammopathy is reported. A 60-year old male, who had a history of IgA monoclonal gammopathy, presented with haemoglobinuria and colic pain. Flow cytometry showed CD55negative/59dim peripheral red cells, and bone marrow examination disclosed MDS. Eleven months, he developed later AML with disappearance of the PNH clones, although the monoclonal gammopathy persisted. The relationship between PNH and MDS has not fully been assessed, although our findings indicate that these triple clonal disorders, all coexisted in one patient.