Utility of the modified 5-item frailty index as a predictor of postoperative febrile urinary tract infection in patients who underwent ureteroscopy with laser lithotripsy.

Purpose: This study aimed to assess the effect of the modified 5-item frailty index on perioperative complications and surgical outcomes in patients who underwent ureteroscopy with laser lithotripsy for upper urinary tract stones.

Methods: Patients who underwent ureteroscopy with laser lithotripsy for upper urinary tract stones between 2019 and 2022 were reviewed retrospectively. Assessment was performed using the modified 5-item frailty index based on medical history (hypertension, diabetes, heart failure, chronic obstructive pulmonary disease) and functional status. Patients were categorized into the high (≥ 2) and low (≤ 1) modified 5-item frailty index groups based on the frailty score. We compared the perioperative complications and surgical outcomes between the two groups.

Results: Seventy-one (15.8%) and 393 (84.1%) of the 467 patients were classified into the high and low modified 5-item frailty index groups, respectively. The high modified 5-item frailty index group exhibited a significant association with increased febrile urinary tract infections compared to the low modified 5-item frailty index group [≥ 37.8 °C: 15 (20.3%) vs 13 (3.3%), p < 0.001; ≥ 38 °C: 9 (12.2%) vs 7 (1.8%), p < 0.001]. Surgical outcomes, including operative time and stone-free rate, did not differ significantly between the two groups.

Conclusion: The modified 5-item frailty index is valuable for predicting postoperative complications, particularly febrile urinary tract infections, after ureteroscopy with laser lithotripsy for upper urinary tract stones. This index allows for practical preoperative risk assessment in patients who underwent ureteroscopy with laser lithotripsy.