Prolonged renal failure secondary to antithymocyte globulin treatment in severe aplastic anemia.

OBJECTIVE: To report a case of acute renal failure in a patient with severe aplastic anemia after administration of antithymocyte globulin (ATG). CASE SUMMARY: A 41-year-old man diagnosed with severe aplastic anemia was treated with ATG and cyclosporine. After one dose of ATG (3012 mg, 40 mg/kg), the patient developed anuric acute renal failure, with serum creatinine 3.4 mg/dL (1.2 mg/dL at baseline) and blood urea nitrogen (BUN) 29 mg/dL (13 mg/dL at baseline), which required intermittent hemodialysis. Renal failure resolved with cessation of the drug, serum creatinine and BUN returned to baseline levels, and the patient no longer required hemodialysis. DISCUSSION: ATG is a purified and concentrated gamma globulin, primarily a monomeric immunoglobulin G from hyperimmune serum of horses. It is widely used to treat severe aplastic anemia and to manage acute transplant rejection. This patient had no other confounding factors for the cause of the renal failure. An objective causality assessment using the Naranjo probability scale suggested that ATG was the probable cause of the acute renal failure. Primary glomerular disease was not excluded, as a renal biopsy was not performed. CONCLUSIONS: The association between renal injury and administration of ATG remains unclear; therefore, we recommend that renal function be assessed and carefully monitored prior to and after administration of ATG.

Interstitial nephritis secondary to bevacizumab treatment in metastatic leiomyosarcoma.

OBJECTIVE: To report a case of interstitial nephritis associated with the administration of bevacizumab. CASE SUMMARY: A 26-year-old man diagnosed with metastatic rectal leiomyosarcoma was treated with intravenous bevacizumab 5 mg/kg and received a total of 3 doses at 2 week intervals. His creatinine had increased from 1.0 mg/dL at baseline to 1.6 mg/dL after 2 doses of bevacizumab and to 4.7 mg/dL after the third dose, prompting admission. Acute renal failure was diagnosed, and hemodialysis was initiated. A renal biopsy revealed interstitial nephritis. Renal failure resolved with cessation of the drug, and the patient did not require further hemodialysis. DISCUSSION: Bevacizumab is a recombinant humanized monoclonal immunoglobulin G antibody to vascular endothelial growth factor. Bevacizumab has shown efficacy in treatment of patients with renal cell carcinoma and colorectal cancer and has been approved by the Food and Drug Administration as a first-line treatment for metastatic colorectal cancer. Our patient had no other confounding factors that might have caused renal failure. The presence of primary glomerular disease was excluded by biopsy. According to the Naranjo probability scale, bevacizumab was the probable cause of acute renal failure in this patient. CONCLUSIONS: Bevacizumab can cause acute renal failure by inducing interstitial nephritis. Renal function should be monitored during bevacizumab therapy.