Haemorheological considerations in the pathophysiology of renal impairment in multiple myeloma: Implications for therapy

Azotaemia in patients with myeloma at the time of presentation is regarded as indicating a poor prognosis. Hypercalcaemia, hyperuricaemia, sepsis, nephrotoxic drugs, amyloid and plasma cell infiltration may be important in some cases, but intrarenal haemodynamics, glomerular filtration dynamics, tubular dysfunction and paraprotein nephrotoxicity may be more important. Immunoglobulin light chains which are freely filtered by the glomerulus have been shown to have a high correlation with the presence of renal insufficiency and there is evidence for these proteins being toxic to the renal tubular cells. With forced alkaline diuresis, with plasma exchange in some patients, it has been possible to improve renal function. Experience with 14 patients with multiple myeloma in whom this has been achieved has given new insights into the pathophysiology and guidelines to the various modes of therapy.