Archives of Hellenic Medicine

Last update:

19-Mar-2025

Arch Hellen Med, 42(3), May-June 2025, 347-356

ORIGINAL PAPER

The association between serum calcium levels and the calcium-to-phosphate ratio
and their potential impact on the incidence of peritonitis in patients undergoing peritoneal dialysis

J.K. Fajar,^1,2 A. Rifai,³ N. Samsu,³ A. Gunawan³
¹Brawijaya Internal Medicine Research Center, Department of Internal Medicine, Faculty of Medicine, Universitas Brawijaya, Malang
²Medical Research Unit, Deka Institute, Malang
³Division of Nephrology & Hypertension, Department of Internal Medicine, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia

OBJECTIVE To investigate the association between serum calcium levels and the calcium-to-phosphate ratio and the susceptibility to peritoneal dialysis (PD)-related peritonitis.

METHOD A retrospective analysis was undertaken at Saiful Anwar General Hospital, Malang, Indonesia. Data encompassing the period from July 2019 to July 2021 were extracted from medical records utilizing a standardized pilot form. Subsequent to this, a subgroup analysis was conducted to evaluate corrected calcium employing the formula proposed by Portale, Payne, Jain, and Ferrari in relation to the risk of peritonitis associated with PD. The correlation between calcium levels, calcium-to-phosphate ratio, and the likelihood of PD-related peritonitis was examined through the multiple logistic regression analysis.

RESULTS An analysis was conducted on 123 patients undergoing PD during the study period, with 20 instances of PD-related peritonitis observed. Serum calcium levels equal to or exceeding 8.25 mg/dL were associated with a 6.71-fold increased risk of PD-related peritonitis. Concurrently, an elevated calcium-to-phosphate ratio demonstrated an augmented risk of PD-related peritonitis. In a sub-group analysis, corrected calcium levels, determined by the formulas of Portale and Jain, exhibited superior sensitivity and specificity in predicting the incidence of PD-related peritonitis. Furthermore, the corrected calcium-to-phosphate ratio, calculated using the formula proposed by Ferrari, demonstrated the highest Youden index for predicting PD-related peritonitis.

CONCLUSIONS Increased concentrations of calcium and an elevated calcium-to-phosphate ratio may elevate the susceptibility to PD-related peritonitis in PD patients, underscoring the significance of calcium as a key predictor for PD-related peritonitis.

Key words: Calcium, Calcium-to-phosphate ratio, Peritoneal dialysis, Peritonitis, Predictor.