A case of peritoneal dialysis-related peritonitis caused by dialysate leakage with successful treatment by intravenous and intraperitoneal antibiotic therapy.

Dialysate leakage is one of the causes of peritoneal dialysis (PD)-related peritonitis. The rate of catheter removal in PD-related peritonitis caused by dialysate leakage (PDPDL) is high, and the correct treatment is unclear. We experienced a case of PDPDL that was treated with intravenous and intraperitoneal antibiotic therapy. A 44-year-old Japanese man had high glucose discharge from the exit site after 14 days of initiating PD, and he had a fever and cloudy effluent with a high white cell count. We diagnosed him with PDPDL and began to administer vancomycin and ceftazidime intraperitoneally. However, the peritonitis could not be ameliorated. A culture examination showed Staphylococcus aureus from the effluent of peritoneal cavity and exit site cultures. We began intraperitoneal cefazolin administration according to a drug susceptibility test, but the effluent cell count remained high. As we added intravenous cefazolin administration, his symptoms and cloudy effluent improved, and the effluent cell count normalized. He has not developed any recurrence of dialysate leakage or peritonitis. Our findings suggest that PD-related peritonitis accompanied by other infectious sites, such as PDPDL, should be treated with additional intravenous antibiotic therapy to taking effect on the infectious sites except for peritoneum and to keep plasma concentration of antibiotics sufficient especially in cases with preserved residual kidney function.

Arginase 2 is a mediator of ischemia-reperfusion injury in the kidney through regulation of nitrosative stress.

Kidney ischemia-reperfusion injury is a major cause of acute kidney injury (AKI). Following reduced kidney perfusion, the pathological overproduction of reactive oxygen and reactive nitrogen species play a substantial role in the development of kidney ischemia-reperfusion injury. Arginase 2 (ARG2) competes with nitric oxide synthase for the same substrate, L-arginine, and is implicated in the regulation of reactive nitrogen species. Therefore, we investigated the role of ARG2 in kidney ischemia-reperfusion injury using human proximal tubule cells (HK-2) and a mouse model of kidney ischemia-reperfusion injury. ARG2 was predominantly expressed in kidney tubules of the cortex, which was increased after ischemia-reperfusion injury. In HK-2 cells, ARG2 was expressed in punctate form in the cytoplasm and upregulated after hypoxia-reoxygenation. ARG2 knockdown reduced the level of reactive oxygen species and 3-nitrotyrosine after hypoxia-reoxygenation injury compared with control siRNA. Consistent with these results, in Arg2 knockout mice, abnormal kidney function and the increased acute tubular necrosis score induced by ischemia-reperfusion injury was significantly reduced without any obvious blood pressure changes. Additionally, an accumulation of 3-nitrotyrosine and apoptosis of renal tubule cells were attenuated in Arg2 knockout mice compared with wild-type mice. Inhibition of arginase by Nω-hydroxy-nor-L-arginine alleviated kidney ischemia-reperfusion injury like the results found in Arg2 knockout mice. Thus, ARG2 plays a pivotal role in ischemia-reperfusion-induced AKI by means of nitrosative stress. Hence, an ARG2-specific inhibitor may effectively treat kidney ischemia-reperfusion injury.