High Osmol Gap Hyponatremia Caused by Icodextrin: A Case Series Report.

Recently, hyperosmolar hyponatremia following excessive off-label use of two exchanges of 2 L icodextrin daily during peritoneal dialysis (PD) was reported. We encountered a cluster of 3 cases of PD patients who developed hyperosmolar hyponatremia during on-label use of icodextrin. This appeared to be due to absorption of icodextrin since after stopping icodextrin, the serum sodium level and osmol gap returned to normal, while a rechallenge again resulted in hyperosmolar hyponatremia. We excluded higher than usual concentrations of specific fractions of dextrins in fresh icodextrin dialysis fluid (lot numbers of used batches were checked by manufacturer). We speculate that in our patients, either an exaggerated degradation of polysaccharide chains by α-amylase activity in dialysate, lymph, and interstitium and/or rapid hydrolysis of the absorbed larger degradation products in the circulation may have contributed to the hyperosmolality observed, with the concentration of oligosaccharides exceeding the capacity of intracellular enzymes (in particular maltase) to metabolize these products to glucose. Both hyponatremia and hyperosmolality are risk factors for poor outcomes in PD patients. Less conventional PD prescriptions such as off-label use of two exchanges of 2 L icodextrin might raise the risk of this threatening side effect. This brief report is intended to create awareness of a rare complication of on-label icodextrin use in a subset of PD patients and/or PD prescriptions.

Intraperitoneal Meropenem for Polymicrobial Peritoneal Dialysis-Related Peritonitis.

With the current rise in multiresistant gram-negative bacteria, carbapenems are more frequently used. Surprisingly, limited data exist on the pharmacokinetics of meropenem in peritoneal dialysis (PD)-related peritonitis. We report on the pharmacokinetics of repeated intraperitoneal (IP) meropenem during 21 days as treatment for polymicrobial multiresistent PD-related peritonitis.Our current report supports daily doses of 125 mg/L intraperitoneal meropenem in all bags as an effective and safe modality in the treatment of PD-associated peritonitis with multiresistant microorganisms. No signs of over- or underdosing were found based on serial drug concentration measurements at fixed time points up to 21 days.