Role of inflammatory markers in predicting spontaneous passage of ureteral stones less than 10 mm

Introduction: In ureterolithiasis, the prediction of spontaneous passage poses a challenge for urologists. Moreover, there is controversy surrounding the preferred management approach, whether medical or surgical, as each approach has its disadvantages. Procalcitonin and other inflammatory markers were studied for predicting stone passage spontaneously, but their significance remains controversial. This study aims to assess the association between these markers, especially procalcitonin, and spontaneous ureteral stone passage.

Materials and methods: In this multicenter prospective cohort study from March 2022 to October 2023, consecutive patients with a single unilateral distal ureteric stone less than 10 mm were enrolled. Exclusion criteria were specified. Patients underwent medical expulsive therapy (MET) and were monitored for stone passage. The significance level was set at p < 0.05.

Results: Out of 94 patients enrolled, 72.3% were male and 27.7% were female, with a mean age of 38.84± 10.41 years. Stone sizes varied, with the most common range being 4 mm- 5.9 mm. Participants were categorized based on spontaneous stone passage as spontaneous stone passage (SSP) and non-SSP. No significant differences were observed in most demographic and laboratory variables. However, serum procalcitonin and C-reactive protein showed significant differences between the SSP and non-SSP groups.

Conclusions: Although several inflammatory markers were studied to predict the spontaneous passage of the ureteral stone, the current study concluded that only elevated procalcitonin, C-reactive protein, and large stone diameter decrease the chance of spontaneous ureteral stone passage.