Where the kidney is concerned, how much mannitol is too much?

OBJECTIVE

To report a case of mannitol-induced acute renal failure (ARF).

CASE SUMMARY: A 31-year-old woman who had been on long-term warfarin therapy for atrial fibrillation was admitted to the hospital with hemoptysis. Following reversal of her anticoagulation, she had a tonic-clonic seizure nine days after admission. An emergency computed tomography scan revealed cerebral edema, which was initially treated with hyperventilation and steroids. Two days later, a repeat scan showed progression of the cerebral edema with midline shift. Mannitol 550 g was infused over the next 28 hours, precipitating ARF. Despite prompt hemodialysis to reverse the renal failure, the patient died. This case of apparent mannitol-induced ARF illustrates several pathophysiologic effects of this agent.

DISCUSSION: Case reports in the literature discussing mannitol-induced ARF are reviewed and compared. A relationship between dose and ARF and its reversal with hemodialysis is postulated.

CONCLUSIONS

It is likely that sufficient doses of mannitol may lead to ARF. Limitation of dose may prevent and treatment with hemodialysis may reverse ARF in these instances.