Myeloproliferative neoplasms related glomerulopathy

Myeloproliferative neoplasms (MPNs, formerly called chronic myeloproliferative disorders) are clonal hematopoietic stem cell disorders characterized by the expansion of one or more of the myeloid lineages, including polymorphonuclear, erythroid, megakaryocytic, and mastocytic. The major complications of MPN are transformation into acute myeloid leukemia (occurring particularly in chronic myelogenous leukemia) and thrombotic and hemorrhagic events (most commonly observed in polycythemia vera and essential thrombocythemia). Renal involvement by MPN is infrequent. MPN-related glomerulopathy enlarges the spectrum of glomerular diseases associated with haematological neoplasms. MPN-related glomerulopathy is an under recognized late renal complication of MPN with poor prognosis. It is characterized clinically by heavy proteinuria and renal insufficiency. The histologic features of MPN-related glomerulopathy include variable degree of mesangial sclerosis and hypercellularity, segmental sclerosis, features of chronic thrombotic microangiopathy, and intracapillary hematopoietic cell infiltration. PDGF and TGF beta likely have a crucial role in the pathogenesis of MPN-related glomerulopathy. Furthermore, aggregation of circulating hematopoietic cells within glomerular capillaries could potentially result in endothelial injury and morphologic changes resembling chronic thrombotic microangiopathy. Greater awareness of this entity is needed to define diagnosis and possible therapies. (C) 2012 Societe nationale francaise de medecine interne (SNFMI). Publie par Elsevier Masson SAS. Tous droits reserves.