Urosepsis after ureterorenoscopy, intraoperative recognition of type-IV stones could change clinical practice

Abstract

Objectives: Urosepsis currently accounts for half of all post flexible ureterorenoscopy (F-URS) complications, with an incidence of up to 4.3%. It represents a quarter of all septic episodes in adults and 2% of hospital spendings. The primary objective of this study was to define the predictive clinical parameters that increase the risk of urosepsis after F-URS.

Subjects/patients (or materials) and methods: This prospective multicentric study evaluated patients who underwent F-URS for calculus between June 2016 and June 2018 in eleven French centers. Clinical, bacteriological, morpho-constitutional stone data, intraoperative information and complications were compared. Risk factors for postoperative urosepsis were identified and analyzed.

Results: We included 486 F-URS in 432 patients. The ureter was prepared using a double J stent in 51% of cases, a digital endoscope was used in 56% of patients with a median operative time of 120 min IQR (90-125) and using a sheath in 90% of cases. Postoperative urosepsis was observed in 18 patients (4%) with a median time to onset of 2 days IQR (1-5). The presence of coronary insufficiency: 3 (17%) vs 14 (3%) p = 0.005, a larger stone diameter: 11 cm [9-17] vs 10 cm [8-13] p = 0.02, a positive preoperative urine culture even when treated: 3 (17%) vs 56 (12%) p = 0.04, as well as the final composition of the type IV calculus (carbapatite or struvite) 5 (28%) vs 20 (4%) p < 0.001, were significantly associated with the occurrence of urosepsis. In multivariate analysis, only the presence of a type IV stone (OR = 14.0; p = 0.025) remained significant.

Conclusion: Ureteroscopic treatment of a type IV stone (carbapatite or struvite) in a patient should raise concerns about the risk of post-operative urosepsis. When recognized intraoperatively, they should lead to a pyelic urinary sample and prolonged clinical surveillance.

Keywords: Carbapatite; Renal stone; Stone composition; Struvite; Ureterorenoscopy; Urosepsis.