Intractable pruritus in chronic myelomonocytic leukaemia and myelodysplastic syndromes: a case series.

Intractable pruritus without visible primary skin lesions and refractory to antihistamines as a primary presentation of chronic myelomonocytic leukaemia (CMML) and myelodysplastic syndrome (MDS) is not well recognised. We present two cases of CMML and two cases of MDS with this challenging symptom. In two of them, the pruritus preceded the diagnosis of MDS/CMML by months. Various chemotherapeutic and immunosuppressive options were used with variable success. In one of the cases, the pruritus persisted despite achieving morphological remission of CMML with azacitidine but had a remarkable complete response to cladribine. The pathogenesis of intractable itching in CMML and MDS remains unclear but seems to be linked to the biology of these diseases and could precede definitive diagnostic features. Earlier diagnosis of these myeloid disorders may therefore be aided by increasing awareness among clinicians of the association with pruritus.