Rapid point-of-care test for diagnosis of peritonitis in peritoneal dialysis patients

BACKGROUND

Periplex® is a rapid point-of-care test based on the detection of interleukin-6 (IL-6) or matrix metalloproteinase-8 (MMP-8) to diagnose peritonitis in peritoneal dialysis (PD) patients.

METHODS

This single-centre study was conducted in Singapore General Hospital from 2019 to 2022. The study recruited PD patients suspected of having peritonitis. Periplex was performed at the presentation and recovery of peritonitis. Primary outcomes were sensitivity and specificity of Periplex at presentation. The positive and negative predictive values of tests were also performed.

RESULTS

A total of 120 patients were included in the study. The mean age was 60.9 ± 14.9 years, 53% were male, 79% were Chinese and 47.5% had diabetes mellitus. Periplex was positive in all patients with peritonitis (n = 114); sensitivity of 100%; 95% confidence interval (CI): 100-100%. Periplex was falsely positive in three patients with non-infective eosinophilic peritonitis, resulting in a low specificity of 50%; 95% CI: 41.1-59.0%. Periplex had a positive predictive value of 97.4% and a negative predictive value of 100%. During recovery from peritonitis, Periplex had high specificity (93.6%) and negative predictive value (98.7%) to indicate the resolution of infection. MMP-8 was more sensitive than IL-6 in detecting peritonitis. Periplex was positive in all patients with peritonitis regardless of the types of PD solutions used.

CONCLUSIONS

Periplex had high sensitivity, and positive and negative predictive values in the diagnosis of peritonitis can be considered as a screening tool for peritonitis. Given its high specificity and negative predictive value, it may also be used to document the resolution of peritonitis.

Diagnostic Accuracy of MMP-8 and IL-6-Based Point-of-Care Testing to Detect Peritoneal Dialysis-Related Peritonitis: A Single-Center Experience

BACKGROUND

Peritoneal dialysis-related peritonitis (PDRP) is the most common complication of peritoneal dialysis (PD), which can lead to poor outcomes if not diagnosed and treated early. We aimed to investigate the diagnostic accuracy of MMP-8 and IL-6-based point-of-care tests (POCTs) in diagnosing PDRP in PD patients.

METHODS

This retrospective chart review study was conducted at a comprehensive kidney center in Qatar. It involved all adult PD patients who underwent PDRP from July 2018 to October 2019 and for whom MMP-8 and IL-6-based POCTs were used to diagnose presumptive peritonitis. Measures of diagnostic accuracy were computed. Peritoneal fluid effluent analysis was the reference standard.

RESULTS

We included 120 patients (68 [56.7%] females, ages 55.6 ± 15.6 years, treatment duration 39.5 ± 30.4 months [range: 5-142 months]). In this population, MMP-8 and IL-6-based POCTs yielded 100% in all dimensions of diagnostic accuracy (sensitivity, specificity, positive and negative predictive values).

CONCLUSIONS

MMP-8 and IL-6-based POCTs might be helpful in the early detection of PDRP. This monocentric observation requires further confirmation in a prospective multicentric setting.

Wearables in Nephrology: Fanciful Gadgetry or Prêt-à-Porter?

Telemedicine and digitalised healthcare have recently seen exponential growth, led, in part, by increasing efforts to improve patient flexibility and autonomy, as well as drivers from financial austerity and concerns over climate change. Nephrology is no exception, and daily innovations are underway to provide digitalised alternatives to current models of healthcare provision. Wearable technology already exists commercially, and advances in nanotechnology and miniaturisation mean interest is also garnering clinically. Here, we outline the current existing wearable technology pertaining to the diagnosis and monitoring of patients with a spectrum of kidney disease, give an overview of wearable dialysis technology, and explore wearables that do not yet exist but would be of great interest. Finally, we discuss challenges and potential pitfalls with utilising wearable technology and the factors associated with successful implementation.