Dipstick for Peritonitis
- A social post highlighted using urine leukocyte dipsticks to help diagnose peritoneal dialysis peritonitis at the bedside. (x.com) - The dipstick was presented as a rapid, low‑cost test option when formal lab work is delayed in dialysis units. (x.com) - If validated clinically, this approach could speed treatment decisions in resource‑limited dialysis settings, the post suggested. (x.com)
Peritoneal dialysis peritonitis is usually diagnosed by counting white blood cells in drained dialysis fluid, and a 2026 study says a urine dipstick may flag those cells at the bedside in minutes. (journals.sagepub.com) Peritoneal dialysis cleans blood through the lining of the abdomen, and peritonitis is an infection in that space that can cause abdominal pain and cloudy fluid. A 2022 JAMA review said the complication affects about 30% to 40% of patients over the course of treatment. (jamanetwork.com) Current International Society for Peritoneal Dialysis guidance defines peritonitis using at least two of three findings: symptoms such as abdominal pain or cloudy effluent, a dialysis-fluid white blood cell count of at least 100 cells per microliter with at least 50% neutrophils after a dwell of at least 2 hours, or a positive culture. (journals.sagepub.com) That standard depends on lab cell counts and cultures, and several clinical protocols say antibiotics should not be delayed when suspicion is high. Stanford Health Care’s 2024 pathway says delaying antibiotics can increase mortality. (med.stanford.edu) The new paper, published in *Peritoneal Dialysis International* in 2026, evaluated leukocyte esterase urine dipsticks on peritoneal dialysis effluent instead of urine. Leukocyte esterase is an enzyme released by white blood cells, and the strip changes color when those cells are present. (journals.sagepub.com) In the clinical arm, researchers analyzed 530 effluent samples from 56 pediatric peritoneal dialysis patients in Khartoum, Sudan, where the dipsticks were already being used for point-of-care testing. On freshly collected samples, the paper reported 100% sensitivity and 100% specificity for diagnosing peritonitis. (journals.sagepub.com) The same study found weaker performance when samples were stored before testing. In 352 freeze-thawed effluent samples from Australia and the United States, sensitivity fell to 78% and specificity was 95% after 1 month of refrigerator storage. (journals.sagepub.com) The authors said smartphone imaging also tracked the strip’s color change and could support semi-quantitative reading, which is a rough measure rather than a formal cell count. They described the approach as most useful for low-resource settings, home-based care, and telehealth. (journals.sagepub.com) The idea is not unique to dialysis fluid: leukocyte esterase strips have also been studied in other body fluids, including ascitic fluid for spontaneous bacterial peritonitis. A 2015 study in *Journal of Laboratory Physicians* reported 95% sensitivity and 96.4% specificity at its chosen cutoff in 103 patients with ascites. (ncbi.nlm.nih.gov) The dipstick does not replace culture, organism identification, or guideline-based treatment. It offers a fast screen for inflammation in fresh effluent, while standard diagnosis and antibiotic decisions still rest on symptoms, cell counts, and microbiology. (journals.sagepub.com)
