Renal replacement therapy in multiple myeloma and systemic amyloidosis

Multiple myeloma and persistence of drug resistance in the age of novel drugs (Review)

Multiple myeloma (MM) is a mature B cell neoplasm that results in multi-organ failure. The median age of onset, diverse clinical manifestations, heterogeneous survival rate, clonal evolution, intrinsic and acquired drug resistance have impact on the therapeutic management of the disease. Specifically, the emergence of multidrug resistance (MDR) during the course of treatment contributes significantly to treatment failure. The introduction of the immunomodulatory agents and proteasome inhibitors has seen an increase in overall patient survival, however, for the majority of patients, relapse remains inevitable with evidence that these agents, like the conventional chemotherapeutics are also subject to the development of MDR. Clinical management of patients with MM is currently compromised by lack of a suitable procedure to monitor the development of clinical drug resistance in individual patients. The current MM prognostic measures fail to pick the clonotypic tumor cells overexpressing drug efflux pumps, and invasive biopsy is insufficient in detecting sporadic tumors in the skeletal system. This review summarizes the challenges associated with treating the complex disease spectrum of myeloma, with an emphasis on the role of deleterious multidrug resistant clones orchestrating relapse.

Immunoglobulin light chain amyloidosis and the kidney

Immunoglobulin light chain amyloidosis and the kidney. Amyloidosis (AL) is a common cause of nephrotic syndrome in nondiabetic, nonhypertensive adults. All adult patients with nephrotic syndrome should have immunofixation of serum and urine as a screen. The finding of a monoclonal protein, particularly of lambda type, should lead to a subcutaneous fat aspirate or bone marrow biopsy to search for amyloid deposits. When the result of either test is positive, a kidney biopsy is unnecessary. The prognosis of patients who have renal amyloidosis depends on the concentration of serum creatinine at presentation and whether an echocardiographic evaluation demonstrates infiltrative cardiomyopathy. Most therapies are directed against the plasma cell dyscrasia present in all patients with AL and can include melphalan and prednisone, high-dose dexamethasone, and, most recently, peripheral blood stem cell transplantation.

Management of renal complications in patients with advanced multiple myeloma

Although the kidney is frequently involved in malignant monoclonal gammopathy, the clinical outcome of the patients varies considerably. We retrospectively assessed the clinical course in seventeen patients with acute and chronic renal failure suffering from multiple myeloma, and analyzed their case history focusing on the therapeutic management, the possible clinical improvement as well as the patients' outcome. Treatment included chemotherapy (n = 17), forced diuresis (n = 3), hemodialysis (n = 11, 7 chronic, 4 intermittent) and plasmapheresis (n = 3). Renal function improved in five patients, and was stabilized compensated in four. Seven patients developed end-stage renal disease, one refused further treatment and was lost for follow up. In addition to renal failure, the most frequent complications included local bone destruction (all), anemia (n = 12), low platelet count (n = 11), and bacterial infections (n = 9). One year survival rate after admission to the nephrology department was 76 percent. Chemotherapy in combination with renal replacement therapy may improve the clinical course even in MM patients with serum creatinine levels above 3.0 mg/dL or end-stage renal disease.

Multiple myeloma and renal failure: one center's experience

Renal involvement remains a major complication of multiple myeloma, particularly in advanced disease. A retrospective analysis was performed of the modes of presentation, treatment and outcome of all patients with multiple myeloma treated in our renal unit between 1987 and 1996. Thirty-four patients were identified: in 26 (76%) the diagnosis of myeloma was made only after referral. Light chains were the most common paraprotein in both serum and urine. Twenty-one (62%) patients underwent renal biopsy: myeloma cast nephropathy was the predominant histological finding in 16 cases. Thirty-one (91%) patients had severe renal failure (GFR < 20 mL/min), with 28 (82%) requiring dialysis within 2 weeks of admission. Despite treatment of presumed precipitaing causes of acute deterioration in renal function, only 1 of these 28 patients subsequently became independent of dialysis. Most had advanced stage myeloma: 29 (85%) were Durie-Salmon stage II or III. Hypercalcemia, sepsis and pathological fractures were the principal complications. Median survival overall was 5 months. The main causes of death were withdrawal of renal replacement therapy (overwhelming myeloma, severe debilitation) and sepsis. Nineteen (56%) patients received long-term (> 1 month) renal replacement therapy with a median survival of 8 months. However, five of these (26%) have survived for more than 12 months on dialysis and report a good quality of life.

Treatment of amyloidosis

Amyloidosis is the extracellular deposition of normally soluble autologous protein in a characteristic abnormal fibrillar form. Systemic amyloidosis and some local forms are progressive, cause major morbidity, and are often fatal. No treatment specifically causes the resolution of amyloid deposits, but therapy that reduces the supply of amyloid fibril precursor proteins can improve survival and preserve organ function. Major regression of amyloid occurs in at least a proportion of such cases, suggesting that the clinical improvement reflects mobilization of amyloid. The clearest evidence for regression of amyloid has been obtained in juvenile rheumatoid arthritis patients with AA amyloidosis treated with chlorambucil. This drug suppresses the acute phase production of serum amyloid A protein, the precursor of AA amyloid fibrils, and is associated with remission of proteinuria and greatly improved survival. In many such patients, scintigraphy with serum amyloid P component shows major regression of amyloid over 12 to 36 months and frequently reveals a discrepancy between the local amyloid load and organ dysfunction. Measurement of target organ function is therefore not an adequate method for monitoring treatment aimed at promoting the resolution of amyloid. In monoclonal immunoglobulin light chain (AL) amyloidosis the aim of treatment is to suppress the underlying B-cell clone and, therefore, production of the amyloid fibril precursor protein. This can be difficult to achieve or sustain and, since the prognosis is so poor, many patients die before benefits of therapy are realized. A recent development has been the introduction of liver transplantation as treatment for familial amyloid polyneuropathy caused by transthyretin gene mutations. This leads to the disappearance of variant transthyretin from the plasma and halts progression of the neurologic disease. Features of autonomic neuropathy frequently ameliorate, and improvement in peripheral motor nerve function has been recently reported. Serum amyloid P component scans show regression of associated visceral amyloidosis. This surgical form of gene therapy holds much promise for patients with familial amyloid polyneuropathy and has been widely adopted. The only other form of amyloidosis in which the supply of the fibril precursor protein can be sharply reduced is beta 2M amyloidosis in long-term hemodialysis patients. Renal transplantation lowers the plasma concentration of beta 2M to normal levels and is associated with rapid improvement of the osteoarticular symptoms. Preliminary observations suggest that the beta 2M amyloid deposits also can regress in some patients.(ABSTRACT TRUNCATED AT 400 WORDS)