Incidence of urinary infections and urosepsis after ureteroscopy for stone disease: a systematic review of literature

Abstract

Background:

Ureteroscopy (URS) and laser lithotripsy are commonly used to treat kidney and ureteric stones. Post-operative infections, including urinary sepsis, can be a potentially serious complication of URS. We aimed to systematically review the incidence and predictors of post-ureteroscopy infections and sepsis.

Design:

Systematic review conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines and registered prospectively with PROSPERO (CRD420251102349).

Data sources and methods:

Only studies in the English language with over 500 patients were included. The Population, Intervention, Comparison, Outcome (PICO) framework for this study examined inpatients with stone disease who underwent ureteroscopy to investigate the incidence of urinary infections and urosepsis.

Results:

Nineteen studies published between 2015 and 2024 were included, totalling 939,860 patients undergoing ureteroscopy for urolithiasis. Patient demographics varied, with a mean age range of 41.3–59.1 years and a male predominance (63.9%). Laser lithotripsy was the primary modality used, with a mean operative time of 53.4 min.

The overall incidence of post-operative infectious complications was 7.8%, ranging from 0.8% to 18.2%. Fever (0.0%–16.2%) and urinary tract infections were the most commonly reported (0.0-12.3%), followed by sepsis (0.0%–7.0%) and septic shock (up to 1.9%). Identified risk factors included female gender, positive pre-operative urine cultures, pre-operative double-J stent placement, patient comorbidities and prolonged operative times.

Conclusion:

Infectious complications predominate among post-ureteroscopy complications. Key factors for post-ureteroscopy infections included female gender, patient comorbidities, positive pre-operative cultures and longer operative times, highlighting the need for targeted management strategies to reduce complications.

Introduction

Ureteroscopy (URS) and laser lithotripsy are widely regarded as the primary treatment modality for urolithiasis and can achieve high stone-free rates with a favourable safety profile. ¹ The choice to pursue ureteroscopy in managing urolithiasis is often influenced by a variety of factors, such as stone size, location, composition, patient anatomy, comorbid conditions and individual patient preferences. ²

Despite its minimally invasive nature and general safety, there are complications associated with URS.^3,4 Among these, infectious complications such as urinary tract infections (UTIs) and urosepsis stand out as a significant concern due to their potential to result in significant morbidity, prolonged hospitalization and, in severe cases, mortality. ⁵

Over recent decades, the application of URS has evolved, propelled by advancements in endoscopic technology, the incorporation of high-definition digital imaging capabilities, disposable ureteroscopes, innovations in laser technology and fragmentation techniques and suction devices. ⁶ These innovations have led to broader indications for URS, improved clinical outcomes and widened its appeal globally.

Existing literature on post-URS infections is vast but heterogeneous, with considerable variability in reported incidences of postoperative urinary tract infection and febrile complications ranging from 0.2% to 18%, and urosepsis reported between 0.1% and 4.3%.^7,8 High heterogeneity across studies further complicates pooled estimates. ⁹ While numerous studies have examined infectious outcomes in specific subpopulations or clinical settings, there is a lack of a comprehensive, high-level synthesis that quantifies the true incidence of UTIs and urosepsis following URS across broad, diverse cohorts. The goal of this systematic review is to determine the pooled influence of infectious complications following ureteroscopy for stone disease in order to identify associated risk factors, and consequently to provide a guide for clinical practice to improve patient outcomes.

Methods

A systematic review of the literature was conducted in July 2025 in accordance with the Cochrane review guidelines ¹⁰ across multiple databases, including Medline/PubMed, Embase, Google Scholar and the Cochrane Central Register of Controlled Trials. All studies from January 2000 up to July 2025 were included. The review was registered in PROSPERO, on which the protocol can be accessed, with registration number CRD420251102349.

Patient/population, intervention, comparison and outcomes statement

The PICO statement for this systematic review is as follows: In adult patients with urolithiasis (P) who underwent ureteroscopy, what are the risk factors or predictors (I) for developing post-operative infectious complications (e.g. UTIs, sepsis, fever), compared to patients who represent the general population (C)?

Inclusion criteria

• Studies published between 2000 and 2025.

• Studies reporting at least 500 patients to ensure data robustness and minimize small-study bias.

• Adult patients (⩾18 years) who underwent ureteroscopy for urolithiasis.

• Studies published in the English language.

Exclusion criteria

• Case reports, narrative/systematic reviews and laboratory or experimental studies.

• Studies involving the paediatric population.

• Studies focused on procedures other than ureteroscopy (e.g. percutaneous nephrolithotripsy)

• Studies in which URS was performed exclusively for indications other than kidney stones.

• Studies in which post-infectious complications were not explicitly defined or reported.

Search strategy and study selection

A systematic review of the literature was conducted in July 2025 in accordance with the Cochrane review guidelines ¹⁰ across multiple databases, including Medline/PubMed, Embase, Google Scholar and the Cochrane Central Register of Controlled Trials. All studies from January 2000 up to July 2025 were included.

Two independent reviewers (A.P.; T.H.) screened the titles and abstracts. Full-text articles were reviewed for eligibility based on inclusion/exclusion criteria. Any disagreements were resolved by a senior reviewer (B.K.S). The systematic review of the literature was performed in accordance with the Preferred Reporting Items for Systematic Review and Meta Analysis (PRISMA) guidelines. ¹¹ The study selection process has been described using a PRISMA flow diagram (Supplementary Material). The search strategy was conducted to find relevant studies with Medical Subject Headings (MeSH): (‘Urinary Infection*’ OR Sepsis OR UTI) AND (Ureteroscopy OR URS OR RIRS). Additionally, search terms included ‘ureteroscop*’, ‘intrarenal’, ‘URS’, ‘retrograde intrarenal surgery’, ‘RIRS’, ‘risk factor’, ‘complications’, ‘infection’, urinary tract infection’, ‘UTI’, ‘sepsis’, ‘septic shock’, ‘systemic inflammatory response syndrome’ and ‘death’. Boolean operators ‘AND’ and ‘OR’ were used to refine the results.

The outcomes of interest included the following variables: author(s), year of publication, journal, study design, sample size, mean age, gender distribution, indications for ureteroscopic intervention and pre-operative assessments (including urine culture, imaging modalities, and antibiotic prophylaxis). Procedural details such as anaesthesia administered, ureteroscope utilized, access sheath use, fragmentation device employed, implementation of post-operative drainage and mean operating time were also recorded. The primary outcome measures evaluated were the stone-free rate (SFR) and the incidence of complications. Secondary outcomes include measures regarding pre-operative urine culture results, co-morbidities, stone characteristics and antibiotic use.

Descriptive statistical analysis was performed using the latest version of IBM SPSS Statistics (version 29.0, released in 2022). As this study is a systematic review of published data, no individual-level statistical testing was conducted. Reported summary measures were extracted as presented in the original studies. Continuous variables were recorded as mean ± standard deviation (SD) or median (interquartile range, IQR) and categorical variables as counts and percentages. Assessments of data normality and analyses of independent factors were based on the statistical methods reported in each study. Descriptive comparisons were then made across studies to identify consistent patterns in infection rates and associated risk factors.

Quality assessment of the studies was estimated via the Cochrane’s tools ROBINS-I for the non-randomized studies ¹² and the NIH checklist for single-arm cohort studies and plotted using the robvis visualization tool. ¹³

Owing to the significant heterogeneity of the studies, specifically the definitions of infectious complications (postoperative fever vs UTI vs sepsis criteria) and the outcome reporting (infectious severity, antibiotic use, peri-operative protocols), a narrative synthesis of data was performed in accordance with the 2020 PRISMA guidelines. ¹¹ Studies were reviewed thematically according to their principal variables. Initial comparisons focused on study characteristics and patient demographics, followed by pre-operative factors (e.g., comorbidities, urine culture status and stent use), intra-operative parameters (operative duration, access sheath use, lithotripsy technique) and stone characteristics. Subsequently, definitions and reported incidences of infectious complications were examined, and risk factors were synthesized qualitatively into patient-related, procedural and microbiological domains.

Results

Study selection and characteristics

A total of 923 records were identified through database searches, with 34 duplicates removed prior to screening. After title, abstract and full-text screening, a total of 19 studies met the inclusion criteria and were included in the narrative synthesis; the remaining articles were excluded as they were not relevant to the research question or did not meet eligibility criteria.

The eligible studies published between 2015 and 2024 were included in this systematic review, although the initial search timeframe began in 2000, reflecting contemporary ureteroscopy practice, encompassing data from 939,860 patients who underwent ureteroscopy (URS) or related endourological procedures for the management of urolithiasis.^14–32 Eighteen studies were retrospective in design,^{14,15,17–32}, and one was prospective in nature. ¹⁶ The sample sizes ranged from 500 patients ²⁹ to over 833,000 patients in a national database study, ³⁰ with a median of 1139 patients (interquartile range approximately 690 – 2,364).^14–32 The duration of patient inclusion periods across studies ranged from 24 to 192 months.^14–32 Despite variability in methodology, the primary aim across all studies was the evaluation of post-operative infectious outcomes following URS procedures. Quality assessment using the ROBINS-I tool indicated a moderate to low risk of bias in the included studies, while evaluation with the NIH checklist showed high adherence to its criteria (Figures 1 and 2).

Figure 1.

ROBINS-I traffic light plot.

Figure 2.

ROBINS-I summary plot.

Inclusion criteria across studies were relatively consistent, generally encompassing adult patients undergoing URS, flexible ureteroscopic lithotripsy (FURS), or retrograde intrarenal surgery (RIRS) for renal or ureteral stones. Several studies restricted inclusion to patients with calculi in specific anatomical locations (e.g. proximal ureter, upper urinary tract) or those undergoing certain types of URS instrumentation (e.g. use of suctioning access sheaths).^{18–21,23,25,26,28,31,32} Conversely, exclusion criteria varied but frequently included patients with anatomical abnormalities (such as a horseshoe kidney, solitary kidney, or transplant kidney), those with active pre-operative UTIs or positive urine cultures, patients on immunosuppressive therapy, individuals with end-stage renal or cardiac disease and cases with incomplete clinical or follow-up data (Table 1).

Table 1.

Details of the included studies.

Study	Year	Study direction	Timeframe (months)	Inclusion criteria	Exclusion criteria	N1
Özsoy et al.	2015	Retrospective	N/A	N/A	Patients with symptomatic UTI prior to surgery and who had prior DJ stenting	927
Somani et al.	2017	Retrospective	33	N/A	N/A	11,885
Ghosh et al.	2017	Prospective	52	Adults who underwent URS procedure for stone disease	N/A	544
Chen et al.	2018	Retrospective	108	Patients treated with flexible ureteroscopic lithotripsy for urinary calculi	Patients with a ureteral stricture, abnormality, or other metabolic disease, such as renal tubule acidosis or hyperparathyroidism	1139
Bai et al.	2019	Retrospective	35	Patients who underwent URSL for ureteral calculi with Holmium	Patients treated with flexible URS lithotripsy or percutaneous nephrolithotomy (PCNL)	1421
Ogreden et al.	2020	Retrospective	120	URS for ureteral calculi	N/A	690
Ma et al.	2021		33	Patients who underwent Flexible ureteroscopic lithotripsy (FUL) for renal and upper ureteral stones	Patients with end-stage renal disease, severe cardiac or lung disease, malignant tumour and immunodeficiency status	2364
Peng et al.	2021	Retrospective	60	Adult patients who received RIRS for renal stone removal and stone composition analysis was available	Patients with autoimmune diseases, taking oral immunosuppressive agents and/or had severe infection in other systems	1493
Hao et al.	2022	Retrospective	62	Patients who were older than 18 years of age, who underwent RIRS surgery in hospital and were followed up and with complete clinical data	Patients with horse- shoe kidney, or that underwent repeat kidney surgeries and with ureteral strictures or obstructions, or with transplanted kidney stones	848
Senel et al.	2022	Retrospective	89	Patients who underwent RIRS for kidney stones	Cases without adequate data and secondary cases	581
Yitgin et al.	2022	Retrospective	24	Patients undergoing RIRS	Patients under the age of 18, ureteral stones, positive preoperative urine culture, ureteral stenting preoperatively, kidney abnormalities such as solitary kidney, horseshoe kidney and transplant kidney	561
Veeratterapillay et al.	2023	Retrospective	72	Patients who underwent primary ureteroscopic laser fragmentation of calculus of ureter, ureteroscopic fragmentation of calculus of ureter NEC and ureteroscopic extraction of calculus of ureter. *analysis did not count for follow up procedures	Patients who had undergone any URS in the 6 months prior to their index admission or if their discharge was after 1 March 2020 (30-day follow-up prospectively defined). Additionally, patients less than 18 years of age, maternity admission, treatment in a private centre and concomitant optical urethrotomy/endoscopic resection of prostate/percutaneous nephrolithotomy (because concomitant procedures could influence the risk of a postoperative infection)	71,305
Castellani et al.	2023	Retrospective	89	Patients with unilateral/bilateral renal stone(s) of any size/location in both kidneys and bilateral stones on follow-up with symptom/stone progression. Patients must be older than 18 years.	Concomitant ureteral lithotripsy, stone located in a calyceal diverticulum, in-tandem procedure and RIRS done as a combined procedure for endoscopic combined intrarenal surgery. Stone size was calculated as the largest diameter	1250
Unno et al.	2023	Retrospective	111	Patients over 18 years old who underwent retrograde flexible ureteroscopy for stone removal	Concurrent endoureterotomy, empyelotomy, or infundibulotormy at the time of ureteroscopy	991
Huang et al.	2024	Retrospective	27	Patients with renal and/or upper ureteral calculi who received FURL as a single form of surgery using 11/13Fr suctioning UAS and SDFU. Patients who were treated by FURL in the first stage without an indwelling double-J tube preoperatively were all included. And patients who underwent unilateral FURL or bilateral FURL were all recruited	Patients with refractory urinary infections, patients with staghorn kidney stone greater than 4 cm or with severe hydronephrosis, patients with severe ureteral stricture or severe ureteral polyp, patients with coagulopathy or cardiopulmonary dysfunction and patients with incomplete clinical data	900
Şahin et al.	2024	Retrospective	84	Patients with a JJ stent during RIRS	Patients younger than 18, with renal abnormalities, with solitary kidneys and without JJ stents	500
Pyrgidis et al.	2024	Retrospective	192	Patients undergoing ureteroscopy due to calculi	N/A	833,609
Giulioni et al.	2024	Retrospective	44	Patients with kidney stones who underwent RIRS	Bilateral procedures, ureteral stone, renal anomalies, RIRS done prone position, or RIRS done as combined procedures for Endoscopic Combined Intrarenal Surgery	6669
Gauhar et al.	2024	Retrospective	36	Adult patients who underwent FU for proximal ureteric or renal stones using any RDS scope only	Distal ureteric stones, procedures for endoscopic combined intrarenal surgery and simultaneous bilateral endoscopic surgery.	2183

Patient demographics and pre-operative variables

The demographic characteristics of patients varied across studies but were broadly representative of the typical population undergoing stone surgery. Male patients were predominant in most studies, with reported proportions ranging from 44.6% ¹⁷ to 74.1% ²⁸ with an overall mean of 63.9%. The mean patient age ranged from 41.3 ± 10.82 years ²⁸ to 59.1 ± 6.74 years, ¹⁸ with a trend toward slightly older populations in studies that included patients with multiple comorbidities or institutional data.

The mean body mass index (BMI), reported in 11 studies,^{15,17,18,20–22,24,26,27,29,32} ranged from 21.6 ± 3.56 kg/m² to 29.4 ± 8.52 kg/m².^18,27 Prevalence of diabetes mellitus (DM) ranged from 6.9% ³⁰ to 18.6%, ²² and hypertension (HTA) was reported in five studies,^{22,26,27,30,32} with rates between 21.3% ³² and 29.8%. ²⁶

Pre-operative double-J (DJ) stent placement was also variably reported. While studies such as Chen et al., and Ma et al. included 100% stented patients, ¹⁷ others like Yitgin et al., specifically excluded them. ²⁴ The presence of a positive pre-operative urine culture was inconsistently reported but ranged from 0% ²⁴ to 41.8%. ²⁶ Antibiotic prophylaxis was administered pre-operatively in most studies,^{14,16,20–22,26,29,31,32} although specifics of agent selection and timing were often lacking. Imaging for pre-operative planning included CT, ultrasound, KUB X-ray and IVU, depending on institutional practices (Table 2).

Table 2.

Demographics and pre-operative parameters of the included studies.

Study	Male % (n)	Mean age (±SD)(y)	Mean BMI (±SD)(kg/m2)	DM% (n)	HTA% (n)	Pre-operative assessment
						DJ stent placement % (n)	Positive UC%(n)	Antibiotic prophylaxis%(n)	Imaging, specify
Özsoy et al.	69.1% (641)	51 (±51.97)	N/A	N/A	N/A	N/A	N/A	100%(927)	CT or IVU
Somani et al.	64.8 % (7701)	48.6 (±15.84)	27 (±5.38)	N/A	N/A	18.3% (2179)	N/A	N/A	N/A
Ghosh et al.	63.8% (347)	56 (±16.3)	N/A	N/A	N/A	28.1% (153)	10.3% (56)	100% (544)	N/A
Chen et al.	44.6% (508)	47.1 (±12.07)	21.9 (±4.18)	N/A	N/A	100% (1139)	N/A	N/A	KUBXray and CT
Bai et al.	61.9% (880)	59.1 (±6.74)	21.6 (±3.56)	18.2% (259)	N/A	3.0%(42)	18.7% (266)	N/A	CT
Ogreden et al.	63.8% (440)	50.3 (±16.5)	N/A	N/A	N/A	N/A	N/A	N/A	KUB Xray and/or CT and/or US
Ma et al.	68.2% (1613)	51.8 (±13.49)	24.6 (±3.23)	N/A	N/A	N/A	N/A	100%(2364)	N/A
Peng et al.	61.2% (913)	49 (±12.56)	24.3 (±6)	N/A	N/A	N/A	13.3% (198)	18.7% (269)	N/A
Hao et al.	67.8% (575)	47.9 (±13.9)	24,3 (±2.64)	18.6% (158)	24.1% (204)	41.3% (350)	14.3% (121)	85.7% (727)	CT
Senel et al.	63.0% (366)	46.1 (±14.2)	N/A	N/A	N/A	8.8% (51)	N/A	N/A	N/A
Yitgin et al.	62.4% (350)	48 (±15)	26,1 (±4.7)	N/A	N/A	0.0%	0,0%	N/A	CT
Veeratterapillay et al.	67.3% (48017)	57 (±17.79)	N/A	16.0% (11417)	N/A	40.0% (28.521)	N/A	N/A	N/A
Castellani et al.	67.5% (844)	48.3 (±18.55)	26.5 (±5.2)	14.2% (178)	29.8% (373)	58.2% (727)	41.8% (523)	84.0% (1050)	KUB Xray or CT
Unno et al.	48.1% (477)	52.4 (±15.87)	29.4 (±8.52)	13.4% (133)	29.8% (295)	32.3% (320)	15.6% (155)	N/A	N/A
Huang et al.	74.1% (667)	41.3 (±10.82)	N/A	N/A	N/A	N/A	N/A	N/A	CT and/or US
Şahin et al.	65.0% (325)	49.8 (±14.06)	28.1 (±4.3)	N/A	N/A	100% (500)	N/A	100% (500)	CT
Pyrgidis et al.	68.8% (57,3791)	53 (±16)	N/A	6.9% (57,179)	21,4% (17,8031)	53.8%(448,447)	N/A	N/A	N/A
Giulioni et al.	66,1% (4407)	48,7 (±17,05)	N/A	N/A	N/A	47,4%(3158)	35,8%(2388)	76,9%(5129)	N/A
Gauhar et al.	67.0% (1463)	47.7 (±17.1)	25.3 (±3.7)	17.3% (377)	21.3% (466)	38.8% (846)	N/A	77.9% (1701)	CT

DJ, Double J; DM, diabetes mellitus; HTA, Hypertension; IVU, Intravenous urogram; KUB Xray, Kidney, Ureter and Bladder Xray; UC, urine culture.

Intraoperative techniques and parameters

A wide range of endourological approaches and instrumentation was described. Both flexible and semi-rigid ureteroscopes were used, with some studies specifying the use of single-use or reusable devices. Laser lithotripsy was by far the most common stone fragmentation method, employed in nearly all studies, often with 100% utilization. Pneumatic and ultrasonic lithotripsy were also reported in a few large cohort studies,^15,19 though less frequently. For example, in the large database study by Somani et al., laser was used in 49.8% of cases, pneumatic lithotripsy in 30.6% and ultrasonic methods in 1.2%. ¹⁵

Operative time was reported in most studies and showed considerable variability. The shortest mean operative time was 30.0 ± 24 min, ²¹ and the longest was 76.3 ± 32.66 min, ²⁶ with an overall mean of 53.4 min.^{14–16,18,20,21,23,24,26–29,31,32} A subset of studies also reported lithotripsy duration, with Castellani et al. ²⁶ noting a mean of 38.7 ± 14.84 min and an overall mean of 26.4 min.^17,26,31,32 Some studies included all patients undergoing URS regardless of complexity, which likely accounts for the broad range in procedure durations. The use of an access sheath was documented in several studies^{15–17,21,24,26–28} and ranged from 19% to over 92%. Intraoperative antibiotic administration was only specified in a minority of studies and was not reported in a standardized fashion^14,15,17,27 (Table 3).

Table 3.

Intra-operative parameters of the included studies.

Study	Ureteroscope		Fragmentation Device %(n)	Mean operative time (SD) (min)	Mean lithotripsy time (SD) (min)	Intra-op antibiotics %(n)	Access Sheath % (n)
	Flexibility %(n)	Disposability %(n)
Özsoy et al.	Semi-rigid:100%(927)	N/A	N/A	41.4	N/A	100%(927)	N/A
Somani et al.	Flexible:15,0%(1781); Semirigid:73.8% (8766)	N/A	Laser:49.8%(5913); Pneumatic:30.6%(3636); US:1.2%(146); EHL:0.3%(34); Others: 1.8%(214)	40.7 (±26.5)	N/A	82.4%(9794)	19.0% (2263)
Ghosh et al.	Flexible: 100%(544); Rigid:100%(544)	N/A	N/A	46.6 (±25.5)	N/A	N/A	37.9% (206)
Chen et al.	Semirigid:100%(1139)	N/A	N/A	N/A	18.1 (±13.97)	100%(1139)	100% (1139)
Bai et al.	Rigid: 100%(1421)	N/A	Laser:100%(1421)	62.3 (±8.1)	N/A	N/A	N/A
Ogreden et al.	N/A	N/A	Laser:44.6%(308); Pneumatic 59.7%(412)	N/A	N/A	N/A	N/A
Ma et al.	N/A	N/A	Laser:100%(2364)	36.2 (±20.65)	N/A	N/A	N/A
Peng et al.	Flexible: 100%(1493)	N/A	Laser:100%(1493)	30.0 (±24)	N/A	N/A	100% (1493)
Hao et al.	Flexible:100%(848); Semirigid:100%(848)	N/A	Laser:100%(848)	N/A	N/A	N/A	N/A
Senel et al.	Flexible: 100%(581); Rigid:100%(581)	N/A	Laser:100%(581)	54.3 (±18.3)	N/A	N/A	N/A
Yitgin et al.	Flexible: 100%(561); Semirigid:100%(561)	N/A	N/A	73.4 (±30.2)	N/A	N/A	54.0% (303)
Veeratterapillay et al.	N/A	N/A	N/A	N/A	N/A	N/A	N/A
Castellani et al.	N/A	Reusable:56,9%(711); Single-use:43,1%(539)	Laser:100% (1250)	76.3 (±32.66)	38.7 (±14.84)	N/A	92,2% (1152)
Unno et al.	N/A	Reusable:49,5%(491) Single-use:50.5%(500)	N/A	57.5	N/A	100% (991)	36,5% (362)
Huang et al.	Flexible: 100%(900)	Single-use:100%(900)	N/A	52.2 (±20.21)	N/A	N/A	100% (900)
Şahin et al.	N/A	N/A	N/A	66.9 (±27.97)	N/A	N/A	N/A
Pyrgidis et al.	N/A	N/A	N/A	N/A	N/A	N/A	N/A
Giulioni et al.	N/A	Reusable: 72.3%(4824)	Laser:72.3%(4824)	56.2 (±26.96)	23.7 (±15.44)	N/A	N/A
Gauhar et al.	N/A	N/A	Laser:99.2%(2165)	54 (±19.3)	25 (±17.8)	N/A	N/A

EHL, electrohydraulic lithotripsy; US, ultrasound.

Stone characteristics

Stone-related data were variably reported but offered important insight into the case complexity. Mean stone size ranged from 9.4 ± 4.8 mm ¹⁹ up to 18.9 ± 11. ¹⁷ Laterality was reported in a few studies and was generally balanced between right- and left-sided stones.^{18–24,26,28} Several studies included bilateral procedures,^{18,19,21,26–30} though most involved unilateral treatment sessions. The presence of single versus multiple stones was described inconsistently, although both were commonly represented across studies.^{16,17,19,21–23,26,31,32}

The stone location was mostly renal, ureteral, or combined. Renal stones predominated in most series, with rates often exceeding 80%. In contrast, studies such as Özsoy et al. included 100% ureteral stones. ¹⁴ The SFR also varied significantly, ranging from 73.3% ²⁹ to over 92.8%. ¹⁹ Differences in imaging follow-up and SFR definitions across studies further contributed to the heterogeneity of reported outcomes (Table 4).

Table 4.

Details of the stone location and size.

Study	Mean stone diameter (SD)(min)	Laterality (right:left)	Calculus quantity				Calculus location		Stone free rate % (n)
			Single stone (n)	Multiple stones (n)	Unilateral (n)	Bilateral (n)	Renal % (n)	Ureteral % (n)
Özsoy et al.	15.33 (±24.5)	N/A	927	0	927	0	0.0%	100%(927)	87.9%(815)
Somani et al.	N/A	N/A	N/A	N/A	N/A	N/A	18.1%(2147)	69.6%(8277)	N/A
Ghosh et al.	14.2	N/A	403	141	N/A	N/A	57.9%(315)	43.6%(237)	86.8%(472)
Chen et al.	18.9 (±11)	N/A	885	254	N/A	N/A	55.7%(634)	22.0%(251)	89.8%(1023)
Bai et al.	11.1(±3.4)	939:660	N/A	N/A	1243	178	0.0%	112.5%(1599)	81.1%(1153)
Ogreden et al.	9.4 (±4.8)	366:322	349	341	688	1	0.0%	100%(690)	92.8%(640)
Ma et al.	9.45(±5.83)	1018:1305	N/A	N/A	N/A	N/A	63.7%(1505)	40.6%(959)	N/A
Peng et al.	17.9(±12.46)	695:747	N/A	289	1442	51	80.6%(1204)	0.0%	N/A
Hao et al.	N/A	425:423	680	168	N/A	N/A	N/A	N/A	N/A
Senel et al.	N/A	276:305	376	205	N/A	N/A	100%(581)	0.0%	73.3%(426)
Yitgin et al.	13.4(±6.1)	287:274	N/A	N/A	N/A	N/A	100%(561)	0.0%	85.9%(482)
Veeratterapillay et al.	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
Castellani et al.	10(±3.77)	1250:1250	288	1165	456	271	200%(2500)	0.0%	90.4%(1130)
Unno et al.	11.7(±7.3)	N/A	N/A	N/A	368	623	N/A	N/A	87.0%(862)
Huang et al.	16.8(±5.8)	540:474	N/A	N/A	786	114	74.7%(672)	49.3%(444)	89.6%(806)
Şahin et al.	N/A	N/A	N/A	N/A	388	112	51.6%(258)	22.4%(112)	73.6%(368)
Pyrgidis et al.	N/A	N/A	N/A	N/A	826695	6914	N/A	N/A	N/A
Giulioni et al.	11 (±5.45)	N/A	3930	2734	N/A	N/A	129.8%(8657)	0.0%	N/A
Gauhar et al.	11.1(±3.7)	N/A	1188	995	N/A	N/A	129.9%(2835)	10.4%(226)	N/A

Post-operative infectious complications

The incidence of post-operative infectious complications varied considerably across the included studies, reflecting differences in patient selection, surgical techniques, perioperative protocols and diagnostic thresholds. Reported rates ranged from 0.8% ¹⁸ to 18.2%, ²⁶ with an overall calculated average of 7.8% depending on the definitions used and the characteristics of the study populations.^14–32 The most commonly reported complications were UTI and post-operative fever, followed by sepsis, and in fewer cases, septic shock and systemic inflammatory response syndrome (SIRS).

Post-operative fever was among the most frequently reported complications, documented in 12 studies. When defined, it was consistently described as a temperature >38°C, with onset typically within 24–72 h after the procedure. The incidence of fever ranged from 0.0% ¹⁶ to 16.2%, ²⁶ highlighting notable inter-study variability.

UTI was reported in 12 studies and also showed wide variability. Some studies defined UTI based purely on the presence of bacteriuria or pyuria, whereas others required clinical symptoms or culture confirmation. This inconsistency likely contributed to the broad range of reported infection rates, ranging from 0.0% ³¹ up to 12.3%. ²⁴

Sepsis was variably defined and reported. Earlier studies tended to rely on SIRS-based definitions, whereas more recent investigations adopted Sepsis-3 criteria. Reported incidence ranged from 0.0% ²⁸ to 7.0%. ²² The largest population-based study by Pyrgidis et al. identified 68,049 cases of sepsis, corresponding to an incidence of 0.7%. ³⁰ Other studies, including those by Bai et al. and Giulioni et al., reported relatively low rates of sepsis, generally < 1%.^18,31 This variability represents a major source of heterogeneity and limits the comparability of reported infection rates.

Septic shock was less frequently documented and reported in studies that explicitly differentiated it from sepsis. Ma et al. ²⁰ described 16 cases, representing 1.9% of their cohort, while Veeratterapillay et al. ²⁵ reported 92 cases, corresponding to 0.5% of their study population. Septic shock was typically defined in accordance with international criteria, requiring vasopressor support and elevated lactate levels, though precise definitions were not consistently applied.

SIRS was specifically mentioned in only two studies. Ma et al. ²⁰ reported 86 cases (3.6%), and Veeratterapillay et al. ²⁵ identified 53 cases (0.1%), using classical SIRS parameters, including fever, leucocytosis, tachycardia and tachypnoea. However, with the transition to Sepsis-3, some studies likely conflated SIRS with early sepsis, further complicating interpretation (Table 5).

Table 5.

Post-operative infectious complications.

Study	Tot complications (n)	Incidence of infectious complications % (N1/N2)	Post-operative Infectious complications (N2)						Definitions of infectious complications
			UTI n(%)	Fever n(%)	Pyelonephritis n(%)	SIRSn(%)	Sepsis n(%)	Septic Shock n(%)
Özsoy et al.	102	2.0%	18 (1.9%)	–	–	–	1 (0.1%)	–	N/A
Somani et al.	510	3.0%	113 (1.0%)	204 (1.7%)	–	–	36 (0.3%)	–	N/A
Ghosh et al.	22	2.4%	4 (0.7%)	0	–	–	9 (1.7%)	–	N/A
Chen et al.	487	4.5%	-	47 (4.1%)	–	–	4 (0.4%)	–	Fever: temperature of > 38.5°C Sepsis: Patients were treated as having sepsis when they had more than two of the following symptoms: (1) obnubilation, (2) systolic pressure of < 100 mm Hg, or (3) respiratory rate of > 22 according to the sepsis-3 guideline.
Bai et al.	24	0.8%	–	–	–	–	11 (0.8%)	1 (0.1%)	Pyuria: 10 or more WBCs per high-power field Urosepsis: 2 or more of the following clinical symptoms or laboratory findings: temperature below 36°C or above 38°C, heart rate >90beats/min, respiratory rate higher than 20 breaths/min or PaCO2 <32 mm Hg and blood WBC count > 12 × 109/L or < 4 × 109/L
Ogreden et al.	446	10.6%	44 (6.4%)	26 (3.8%)	–	–	3 (0.4%)	–	N/A
Ma et al.	N/A	4.3%	–	–	–	86 (3.6%)	–	15 (0.6%)	Septic shock: the need for vasopressors to maintain a mean aretrial blood pressure greater than 65mmHg and a suspected urinary tract infection; hypotension should not have any other possible reasons. SIRS: meeting 2 or more of the following criteria: Temperature > 38.5°C or < 36°C; Heart rate > 90 beats/min; Respiratory rate > 20 breaths/min or PaCO2 < 32 mmHg; WBC > 12×109 /L or < 4×109 /L or > 10% bands Qsofa: meeting 2 or more of the following criteria: Respiratory rate > 22 breaths/min, altered mentation (decrease in GCS) and systolic blood pressure < 100 mm Hg.
Peng et al.	170	5.7%	–	73 (4.9%)	–	–	8 (0.5%)	4 (0.3%)	Fever: body temperature > 38 °C within postoperative 24 h, Urosepsis: meeting two or more criteria of the qSOFA, systolic blood pressure < 100 mmHg, highest respiratory rate > 22 bpm and lowest Glasgow coma score < 15
Hao et al.	N/A	8.8%	–	–	–	–	59 (7.0%)	16 (1.9%)	Sepsis: life-threatening organ dysfunction caused by a dysregulated host response to infection. For clinical operationalization, organ dysfunction can be represented by an increase in the SOFA score by 2 points or more. Septic shock: need for vasopressors to maintain a mean arterial blood pressure greater than 65 mmHg and a suspected urinary tract infection. The observed hypotension could not have any other possible causes, for example, anaesthesia-related hypotension.
Senel et al.	47	8.1%	15 (2.6%)	27 (4.6%)	–	–	2 (0.3%)	3 (0.5%)	Fever: body temperature > 38°C continuing for 48 h during hospital stay Urinary infection: urinary and/or blood culture positivity Sepsis: urinary infection and the presence of ⩾2 Sequential Sepsis-related Organ Failure Assessment [SOFA] score Septic shock: sepsis accompanied by serum lactate level > 2 mmol/L and vasopressor need for mean arterial pressure > 65 mm Hg
Yitgin et al.	141	17.3%	69 (12.3%)	28 (5.0%)	–	–	–	–	N/A
Veeratterapillay et al.	3992	8.4%	3867 (5.4%)	-	821 (1.2%)	53 (0.1%)	1150 (1.6%)	92 (0.1%)	N/A
Castellani et al.	334	18.2%	–	203 (16.2%)	–	–	25 (2.0%)	–	Sepsis: life-threatening organ dysfunction caused by a dysregulated host response to infection
Unno et al.	90	7.6%	64 (6.5%)	–	–	–	11 (1.1%)	–	UTI: patients with pyuria and bacteriuria and/ or positive urine culture
Huang et al.	191	5.1%	–	46 (5.1%)	–	–	0 (0.0%)	–	N/A
Şahin et al.	39	10.6%	48* (9.6%)	48* (9.6%)	–	–	5 (1.0%)	–	UTI/Postoperative fever: body temperature⩾38º within 72 h after surgery
Pyrgidis et al.	89446	8.9%	68049 (8.2%)	–	–	–	6194 (0.7%)	–	N/A
Giulioni et al.	869	7.4%	0 (0.0%)	407 (6.1%)	–	–	84 (1.3%)	–	Fever: an increase in body temperature ⩾38°C Sepsis: ‘ alife-threatening organ dysfunction caused by a dysregulated host response to infection’ and assessed using the quick Sequential Organ Failure Assessment (q-SOFA) score
Gauhar et al.	841	14.2%	–	299 (13.7%)	–	–	12 (0.5%)	–	N/A

^*No distinction between UTI and fever.

Factors predisposing to infectious complications

Key risk factors identified across studies included female gender, positive pre-operative urine culture, elevated patient morbidity, pre-operative double-J stent placement or prolonged stent dwell time and prolonged operative duration. Several additional variables were also noted (Table 6).

Table 6.

Summary of risk factors associated with post-ureteroscopy infectious complications.

Study	Risk Factors
Özsoy et al.	Female gender
Somani et al.	N/A
Ghosh et al.	N/A
Chen et al.	Use of a smaller-calibre ureteral access sheath
Bai et al.	Longer operative times, Positive pre-operative MDR urine culture
Ogreden et al.	Longer interval of time between diagnosis and treatment
Ma et al.	N/A
Peng et al.	Infection stones, female gender, positive preoperative urine test, Postoperative neutrophil ratio > 75%
Hao et al.	Operative time > 67.5 min, HU of hydronephrosis > 6,0, AGR < 1,705, hs-CRP/Alb > 0.06, preoperative JJ placement, urinary nitrite positivity
Senel et al.	Age > 50y, Operative time > 60 min, High R.I.R.S score
Yitgin et al.	Longer operative times
Veeratterapillay et al.	Diabetes mellitus, Preoperative JJ placement
Castellani et al.	Female gender, No antibiotic prophylaxis, Kidney abnormalities, Operative time > 100min
Unno et al.	Reusable ureteroscopes
Huang et al.	N/A
Şahin et al.	Prolonged JJ stent dwell time (>20 days)
Pyrgidis et al.	Same-session bilateral ureteroscopy
Giulioni et al.	Larger stone size (particularly > 2cm)
Gauhar et al.	Larger stone size, Positive preoperative urine culture, Interpolar stones, Preoperative JJ placement

AGR, Albumin-globulin ratio; hs-CRP/Alb, High-sensitivity C-reactive protein/albumin ratio; HU, Hounsfield Unit; MDR, Multi-Drug Resistant; UAS, Ureteral Access Sheath.

The risk of bias assessment, conducted using the ROBINS-I tool, demonstrated that the majority of studies exhibited a low to moderate overall risk of bias. Most domains, including bias due to confounding, selection of participants and classification of interventions, were judged to be at low risk. However, several studies showed moderate to serious risk in domains related to missing data, deviations from intended interventions and selection of the reported result. Overall, while methodological quality was generally acceptable, a few studies presented limitations that could potentially affect the robustness of their findings (Figures 1 and 2).

Discussion

This systematic review of over 900,000 patients across 19 studies provides a comprehensive evaluation of post-operative infectious complications following URS for stone disease. The most frequent complications included UTI, fever and sepsis, with infection rates ranging from 0.8% to 18.2% and sepsis rates up to 7.0%.

These findings reinforce previously published data and support current European Association of Urology guidelines, ³³ which emphasize pre-operative risk stratification and infection control protocols to mitigate infectious complications. Our review, demonstrating post-operative infection rates of 7,8% aligns with a recent meta-analysis estimating urosepsis rates of ~5.0% (95% CI 2.4–8.2%) and identifying common risk factors such as older age, diabetes, ischaemic heart disease, pre-operative stent placement, positive urine culture and longer procedure duration.^7,34–36

A large meta-analysis of over 9500 URS patients identified positive pre-operative urine culture (OR ≈ 2.95), female gender (OR ≈ 1.95), diabetes (OR ≈ 1.55) and extended operative time (mean difference ~11.5 min), and confirmed that stent placement, both pre- and post-operative, increased infectious risk. ⁹ These findings underscore the importance of optimized stent management.

A prospective UK study (n = 462) further demonstrated that positive pre-operative midstream urine sample markedly increased post-operative urosepsis risk, despite pre-operative antibiotic treatment (OR up to 17.5), ³⁷ while analysis of a U.S. Medicare dataset revealed a graded rise in sepsis, ICU admission and mortality with accumulation of these risk factors (from ~1.1% sepsis in patients with none to over 52% in those with nine risk factors). ³⁸

These findings are consistent with a recent pan-European Delphi consensus on intrarenal pressure, which identified the same high-risk characteristics as key contributors to infection. Although no absolute IRP threshold could be established, most experts expressed concern for pressures exceeding 61–80 cm H₂O, supporting the need for strict intra-operative control of irrigation and pressure. ³⁹

Collectively, these findings emphasize that while ureteroscopy remains generally safe, a non-trivial minority of patients experience significant infectious morbidity. Evidence from multicentre and national datasets corroborates our conclusions that pre-operative urine culture status, comorbidity burden, operative time and stent management should inform targeted risk mitigation strategies. In light of these data, clinicians should adopt tailored protocols for high-risk patients, including culture-directed antibiotic therapy, avoiding stent-related morbidity, that is, avoiding unnecessary pre-operative stenting, minimizing stent dwell time and ensuring timely postoperative removal, as recommended by the EAU and AUA guidelines for infection prevention.^1,39

This review is not without limitations. First, the heterogeneity of study designs, outcome definitions and populations precluded formal meta-analysis. Second, most studies were retrospective in nature and subject to reporting and selection bias. Third, key variables such as irrigation pressure, stent duration, laser settings and intraoperative antibiotic use were not uniformly reported. These omissions limit our ability to determine the true impact of individual risk factors. Since we restricted the review to studies with over 500 patients, this might exclude important smaller studies that report on septic complications. Lastly, there were substantial inconsistencies in postoperative infectious outcomes due to a lack of standardized definitions for fever, UTI and sepsis, making direct comparisons challenging.

Clinicians should remain vigilant in identifying high-risk patients and optimizing modifiable factors such as infection control, operative duration and device selection. Future research should prioritize the standardization of infectious definitions and the evaluation of emerging technologies that may influence postoperative outcomes. In particular, advances in retrograde intrarenal surgery (RIRS) increasingly focus on optimizing key intra-operative parameters, collectively referred to as the “quadrifecta” of suction, irrigation, intrarenal pressure (IRP) and temperature (IRT).^40–42 Innovations such as suction-integrated access sheaths, pressure-regulated irrigation systems and real-time IRP and IRT monitoring aim to maintain low intrarenal pressure, enhance fragment evacuation and limit bacterial translocation, thereby potentially reducing postoperative infectious complications.^43–46 Early experimental evidence suggests potential benefits in reducing infectious complications, but well-designed prospective trials are needed to validate these technologies and integrate them effectively into clinical practice. The development of risk-prediction tools and the incorporation of these parameters into clinical workflows may further support personalized, infection-preventive strategies in ureteroscopy.

Conclusion

This systematic review highlights a high incidence of post-ureteroscopy infections, with UTIs and sepsis constituting significant risks following the procedure. Key predictors include female gender, higher patient morbidity, positive pre-operative urine cultures, longer operative time, large stone burden, and stent use and dwelling time, suggesting targeted pre- and post-operative management could reduce complications.

The technological evolution of ureteroscopy is increasingly focused on minimising the risk of complications while improving stone-free rates. Advances such as suction-integrated access sheaths, pressure-regulated irrigation and real-time intrarenal pressure monitoring have the potential to shape a new standard of care, aiming to enhance both patient safety and procedural outcomes.