Pericardial effusion leading to acute renal failure: two case reports and discussion of pathophysiology.

We describe two patients who developed acute renal failure secondary to severe pericardial effusion. In one patient, the pericardial effusion was due to coxsackievirus infection, and in the other patient, it was due to lung cancer. One patient was in cardiac tamponade, and the other was not yet in tamponade, as per echocardiographic criteria. Kidney function was relatively normal in both patients before the pericarditis episodes. In both patients, pericardiocentesis caused immediate massive diuresis with quick recovery of renal function back to baseline. In the first patient, blood urea nitrogen and serum creatinine decreased from 82 mg/dL and 7.6 mg/dL to 71 mg/dL and 4.6 mg/dL in the next 48 hours, then to 23 mg/dL and 1.3 mg/dL 5 days after the pericardiocentesis. In the second patient, blood urea nitrogen and serum creatinine decreased from 109 mg/dL and 2.9 mg/dL to 40 mg/dL and 0.9 mg/dL in the next 48 hours and 17 mg/dL and 0.7 mg/dL 3 days after release of tamponade. Pericardial effusion can affect renal hemodynamics in many different ways, including increased atrial natriuretic peptide secretion, increased renal efferent nerve activity, and increased secretion of renin and vasopressin. Although pericardial effusion is a complication of uremia, acute renal failure per se can occur in nonuremic cases of pericardial effusion. Two cases of acute renal failure resulting from pericardial effusion were reported in the literature in the past. Pericardial effusion should be included in the broad list of prerenal causes of acute renal failure. Copyright 2002 by the National Kidney Foundation, Inc.