Closing the loop on catheter-associated urinary tract infections: A prospective risk assessment and scoring system for the early prediction and prevention of catheter-associated urinary tract infection

Abstract

Background:

Catheter-associated urinary tract infections (CAUTI) are among the most common healthcare-associated infections, particularly in hospitalised patients requiring prolonged catheterisation. Despite standard protocols, preventable lapses in catheter care and clinical practices contribute to the incidence of these infections.

Aims and Objectives:

This study aimed to identify significant risk factors and develop a point-based CAUTI Risk Scoring System for early prediction and intervention.

Materials and Methods:

A prospective observational study was conducted over six months at a tertiary care hospital, including 100 catheterized adult inpatients. Demographic data, Clinical variables, and catheter practices were documented. CAUTI was confirmed by urine culture. A risk stratification model was developed by assigning weighted scores to statistically significant variables, categorising patients into low, moderate, and high CAUTI risk groups. A domain-wise heatmap visually represented the novelty and interdisciplinary relevance of the study’s contributions across ten clinical research domains.

Results:

Among the 26% of study participants who had CAUTI overall, the important procedural predictors were open-type drainage systems (p < 0.00001), kinking of catheter tubing (p < 0.00001), and raised urobag placement (p < 0.00001). Clinical risk variables included diabetes mellitus (p = 0.00001), catheter duration greater than 7 days (p = 0.0043), female sex (p = 0.0023), and immobility (p = 0.0014). Strong early signals included turbid urine (p = 0.00004) and unexplained fever (p = 0.00001). A cumulative risk rating system placed patients into low (0–3), moderate (4–6), and high-risk (≥7) categories.

Conclusions:

This study presents the first validated CAUTI Risk Scoring System, including clinical, procedural, and early bedside indicators. The scoring tool enables proactive intervention and serves as a necessary adjunct to infection prevention plans in hospital environments.

INTRODUCTION

Catheter-associated urinary tract infections (CAUTIs) represent a substantial proportion of healthcare-associated infections worldwide, accounting for nearly 40% of all nosocomial infections.[1] Indwelling urinary catheters are indispensable in managing acute and chronic urinary dysfunction; however, their use carries a significant risk of infection, particularly when catheter care protocols are inconsistently applied. Approximately 80% of hospital-acquired UTIs are directly attributed to urinary catheters, underscoring the critical importance of appropriate catheter management in the clinical settings.[2,3,4,5]

Catheterization is frequently employed in emergency departments, critical care units, and surgical wards, with nearly one-quarter of hospitalized patients undergoing the procedure at some point during admission.[6] Approximately 7% of inpatients are managed with indwelling catheters.[7] Catheterization may extend over several years in certain patient populations, such as those in long-term care or home-based support.[8] Catheterization periods up to 14 days are classified as short-term, while those exceeding 2 weeks are considered long-term.[9,10]

The duration of catheterization, configuration of the drainage system, positioning of the urobag, and adherence to aseptic insertion techniques are all pivotal factors influencing infection risk.

Although catheter care has traditionally been the purview of nursing personnel, the widespread involvement of medical trainees and allied health students in academic institutions introduces variability in adherence to evidence-based protocols. Training deficiencies and lapses in aseptic technique can contribute significantly to elevated CAUTI rates.

This single-center, prospective, and observational study aims to critically evaluate the impact of catheter management practices on infection rates in hospitalized patients. By examining modifiable procedural factors – such as drainage system type, fixation level, drainage tube kinking, and the role of prophylactic antibiotic administration-this study seeks to inform targeted interventions, reinforce institutional protocols, and enhance clinical training programs to mitigate the burden of catheter-related infections.

MATERIALS AND METHODS

This prospective, observational, and cohort study was conducted over 6 months (March to August 2024) at a tertiary referral center and academic teaching hospital after getting institutional ethical committee clearance and informed consent from the patients. Real-time data were collected from the catheterized adult inpatients to evaluate procedural and clinical risk factors for CAUTI. A point-based CAUTI risk scoring system was subsequently derived from statistically significant variables within this cohort and internally validated using receiver operating characteristic (ROC) curve analysis to assess its predictive accuracy. A total of 100 adult inpatients who underwent urinary catheterization during their hospital stay were enrolled from both private and general wards. Inclusion criteria comprised patients catheterized for various clinical indications, including acute urinary retention, monitoring of urine output, and perioperative care. Patients with preexisting urinary tract infections (UTIs) at the time of catheterization were excluded.

Patient-specific clinical information such as demographic details, indication and duration of catheterization, type of urinary drainage system (open vs. closed), level of urobag fixation (above or below waist), presence of drainage tube kinking, volume and characteristics of urine drained, mobility status, presence of fever, and the presence of comorbidities such as diabetes mellitus were collected. Documentation of whether antibiotic prophylaxis was administered before catheter insertion and the time of catheter removal was also included.

Urine cultures were obtained only when patients exhibited clinical signs suggestive of UTI, such as fever without a source, suprapubic pain, or turbid urine (clinically significant CAUTI). This approach may have underestimated asymptomatic bacteriuria; however, it reflects standard practice and is consistent with the Infectious Diseases Society of America (IDSA)/Centres for Disease Control and Prevention guidelines, which discourage routine surveillance cultures to prevent unnecessary antimicrobial use. The decision to obtain cultures was made in real-time by the treating clinical team based on these bedside indicators, independent of any formal scoring system. Thus, the cultures were the part of routine clinical care triggered by early clinical suspicion, not by a predefined algorithm. The cumulative CAUTI risk scoring system was formulated only after the study period, using retrospectively analyzed data from these patients.

Development of catheter-associated urinary tract infection risk scoring system

We developed a CAUTI risk scoring system using prospectively collected clinical and procedural data to facilitate structured risk stratification and bedside applicability [Figure 1].

Figure 1.

Catheter-associated urinary tract infection risk assessment flowchart: Integrating procedural, patient, and clinical indicators

The scoring system was derived post hoc from the variables that showed statistically significant associations with culture-proven CAUTI in our cohort. Risk factors were selected based on strength of association (odds ratio [OR], relative risk [RR]), clinical relevance, and feasibility of bedside assessment. Each variable was assigned a weighted score ranging from +1 to +3 based on increasing odds of infection. Protective factors, such as timely antibiotic administration and catheter removal within 48 h, were assigned negative scores based on their inverse association with CAUTI incidence. The final scoring model comprised three domains: (i) Catheter care practices (e.g., drainage system type, bag positioning, and tubing kinking), (ii) patient-specific clinical factors (e.g., diabetes mellitus, duration of catheterization, age, and mobility), and (iii) early clinical indicators (e.g., urine turbidity and unexplained fever) [Table 1]. A cumulative score was calculated for each patient. Risk levels were stratified as follows: Low risk (score 0–3), moderate risk (4–6), and high risk (≥7) [Table 2]. This scoring tool was then retrospectively applied to all 100 patients in the cohort to assess predictive correlation and practical utility.

Table 1.

Expanded catheter-associated urinary tract infections risk scoring system for bedside risk stratification

Domain	Risk factor	OR	P	Assigned score	Analytical justification
Catheter care factors	Open-type drainage system	13.39	<0.00001	3	OR >13 Powerful association
	Kinking of catheter tubing	18.7	<0.00001	3	OR >13 Powerful association
	Urobag positioned above waist	12.67	<0.00001	2	OR 5–12 Intense not maximal
	Lack of daily catheter care documentation	6.45	0.0032	2	OR 5–12 Intense not maximal
Patient-related factors	Diabetes mellitus	8.2	<0.00001	2	OR 5–12 Intense not maximal
	Catheter duration >7 days	5.23	0.0043	2	OR 5–12 Intense not maximal
	Female sex	4.81	0.0023	1	OR 3–5 Moderate association
	Immobility	4.43	0.0014	1	OR 3–5 Moderate association
	Age >60 years	4.2	0.006	1	OR 3–5 Moderate association
Clinical indicators	Turbid/purulent urine	13.88	0.00004	3	OR >13 Powerful association
	Fever without source	27.27	<0.00001	3	OR >13 Powerful association
Protective factors	Antibiotic use (protective)	0.08	<0.0001	−2	OR <1 Inverse association (protective)
	Catheter removed <48 h (protective)	0.08	0.0027	−2	OR <1 Inverse association (protective)

OR: Odds ratio

Table 2.

Risk score interpretation matrix for catheter-associated urinary tract infections management

Cumulative score	Interpretation	Suggested clinical action
Score <0	Protected/very low risk	The patient may have received optimal preventive care; continue standard protocol
0–3	Low risk	Continue routine catheter care. Monitor visually; No immediate escalation
4–6	Moderate risk	Intensify surveillance. Consider early culture and review of care protocols
≥7	High risk	Immediate catheter reassessment, urine culture, and preemptive treatment or urology consult are also needed

Based on our findings, we propose a practical, point-based CAUTI risk scoring system to stratify hospitalized patients by their likelihood of developing CAUTIs. This system integrates modifiable procedural lapses, patient-specific vulnerabilities, and early clinical indicators – all shown to be statistically significant in our study.

Procedural risk components include three key catheter care violations: use of open-type drainage systems (OR: 13.39), urobag positioned above waist level (OR: 12.67), and kinking of the catheter tubing (OR: 18.7). Each of these factors independently increased infection risk and can be visually inspected and corrected, making them suitable for inclusion in a dynamic scoring model. We recommend assigning three points each for open drainage and catheter tubing kinking due to their higher OR, and 2 points for elevated urobag placement. Lack of catheter care documentation increased the likelihood of infection, with an OR of 6.45, and was given 2 points in the risk scoring system.

Patient-specific risk components include diabetes mellitus (OR: 8.2) and prolonged catheterization beyond 7 days (OR: 5.23) were given 2 points to the total score, whereas age more than 60 years (OR: 4.2), female sex (OR: 4.81), and immobility (OR: 4.43) were given 1 point each.

Early elinical indicators, such as turbid or purulent urine (OR: 13.88), and fever without source (OR: 27.27) correlated strongly with infection, warranting 3 points each in the risk score. While not diagnostic alone, these findings may serve as critical bedside flags prompting early testing and antimicrobial review.

Antibiotic administration (OR: 0.08) and catheter removal within 48 h (OR: 0.08) were found to be protective, warranting subtracting 2 points in cases. Antibiotic administration is appropriately used for high-risk patients, with caution given to antimicrobial stewardship.

Scoring for each variable in the CAUTI risk scoring system was assigned based on the strength of statistical association observed in the study. A score of +3 was given to predictors with an OR of 13 or higher and a P < 0.0001, indicating a powerful and statistically significant association with CAUTI. Variables with an OR between 5 and 12 and a P value below 0.01 were assigned a score of +2, reflecting an intense but not maximal effect size. A score of +1 was designated for moderate predictors, defined by an OR between 3 and 5 with P < 0.01. Conversely, a score of −2 was applied to protective factors, identified by an OR < 1 and a statistically significant inverse association (P < 0.01).

The cumulative score can be interpreted as follows: a total of 0–3 suggests low risk, warranting routine catheter care and observation; scores of 4–6 indicate moderate risk, necessitating intensified surveillance and possible microbiological evaluation; and scores of 7 or more denote high risk, justifying immediate catheter reassessment, urine culture, and potential initiation of empirical antimicrobial therapy. Scores below zero may indicate patients who have received effective preventive measures and are at minimal risk.

This stratified scoring system guides real-time clinical decision-making, flags high-risk patients early, and enables targeted intervention. Its foundation in prospectively gathered real-world data ensures contextual relevance and adaptability to similar tertiary care settings. When implemented consistently, it may serve as a valuable adjunct to existing infection control protocols and enhance the precision of CAUTI prevention strategies.

To evaluate the discriminative capacity of the CAUTI risk scoring system, a ROC curve was constructed using cumulative patient risk scores and corresponding culture-confirmed CAUTI outcomes [Figure 2]. The resulting curve demonstrated a robust predictive performance, with an area under the curve (AUC) of 0.94, indicating excellent diagnostic accuracy. A score distribution analysis was performed in parallel, revealing a clear stratification between CAUTI-positive and CAUTI-negative patients. Notably, the majority of patients who developed CAUTI clustered at cumulative scores ≥7, while lower scores were predominantly associated with CAUTI-negative outcomes. This distribution provided empirical support for defining ≥7 as the high-risk threshold, as it represented a critical inflection point beyond which the likelihood of infection significantly increased. Together, the ROC analysis and score distribution curve affirm the validity of the proposed scoring model as a reliable tool for prospective risk stratification and early clinical decision-making.

Figure 2.

Receiver operating characteristic analysis and outcome-based risk score stratification in catheter-associated urinary tract infection

The CAUTI risk scoring system stratifies patients into four risk categories based on their cumulative score, which was derived from statistically weighted risk factors identified in this study. The threshold of ≥7 points was chosen to define the high-risk category, corresponding to a clustering of culture-positive CAUTI cases within the cohort. Patients scoring ≥7 typically presented with two or more high-weighted risk factors (e.g., kinking of catheter tubing, open-type drainage system, and turbid urine) or multiple moderate-risk contributors, justifying early intervention before progression to severe infection. The moderate-risk group (scores 4–6) represented patients with either a single high-risk factor or a combination of moderate-risk factors, for whom intensified surveillance and early culture guidance were appropriate. A score of 0–3 was considered low risk, encompassing patients with minimal or isolated moderate-risk exposures and who, in the study, demonstrated low CAUTI incidence; routine catheter care was deemed sufficient for this group. Scores below 0 indicated the presence of protective factors without significant risk indicators and were classified as very low risk or protected, suggesting effective adherence to preventive protocols. This tiered framework is both clinically pragmatic and data-driven, aligning the scoring system with observed outcome patterns while promoting timely and targeted infection control strategies.

Raising the high-risk cut-off beyond a score of 7 would diminish the sensitivity of the scoring system by potentially excluding a substantial proportion of patients who, despite having multiple moderate or a single high-risk factor, were observed to develop culture-positive CAUTI in this cohort. Such a shift would delay critical clinical interventions and weaken the model’s predictive accuracy, as several patients with scores between 7 and 9 demonstrated early signs of infection and benefited from a timely response. Therefore, maintaining the threshold at ≥7 ensures that the scoring system remains sensitive enough to capture high-risk individuals before infection progresses, preserving the intended purpose of early risk identification and prevention.

A novelty heatmap [Figure 3] was constructed to visually map the study’s ten unique contributions against ten interdisciplinary research domains, with scores ranging from 3 (moderate novelty) to 5 (high novelty). Each contribution was independently evaluated for its cross-domain relevance and innovation, enabling structured identification of the study’s translational impact across clinical, educational, and implementation frameworks.

Figure 3.

Heatmap of unique contributions across research domains

Statistical analysis

All statistical analyses were conducted using IBM SPSS Statistics version 26.0 (IBM Corp., Armonk, NY, USA). Descriptive statistics were employed to summarize the patient demographics, catheter-related variables, and procedural characteristics. Categorical variables – such as type of drainage system, urobag positioning, presence of tubing kinking, and patient comorbidities – were analyzed using the Pearson’s Chi-square test or Fisher’s exact test, as appropriate. P < 0.05 was considered statistically significant. The strength of association between individual risk factors and the incidence of culture-confirmed CAUTIs was quantified using ORs and RRs, each with corresponding 95% confidence intervals (CIs). Variables showing significant associations were subsequently incorporated into a weighted CAUTI risk scoring system.

To evaluate the diagnostic performance of the scoring system, a ROC curve was constructed using the cumulative scores and corresponding CAUTI outcomes. The area under the ROC curve (AUC) was calculated to assess the model’s discriminative ability, with a value of 0.94 indicating excellent predictive accuracy. In addition, a score distribution histogram was generated to visualize the clustering of CAUTI-positive versus CAUTI-negative patients across the score spectrum. Most infection cases were observed at or above a cumulative score of 7, which empirically supported the selection of ≥7 as the high-risk threshold in the scoring matrix. This multi-tiered analytical approach provided a robust validation of the scoring model and enabled clinically relevant risk stratification for targeted CAUTI prevention strategies.

Model calibration was assessed by comparing predicted risk categories against observed CAUTI outcomes to determine the accuracy of stratification thresholds. The scoring system demonstrated good internal consistency, with a stepwise increase in infection prevalence corresponding to ascending score ranges, supporting its clinical validity. While formal external validation was not performed in this single-center study, internal validation through ROC curve analysis yielded a high AUC value (0.94), underscoring excellent discriminatory power. Although a formal sample size calculation was not prespecified, the study cohort of 100 patients provided sufficient statistical power to detect significant differences across key variables, particularly those with high effect sizes (e.g., OR > 5).

RESULTS

This study enrolled 100 adult inpatients who underwent urinary catheterization for various clinical indications. Table 3 provides a comprehensive overview of key catheterization and urinary parameters across our cohort of 100 patients, including Urobag configuration, drainage volume and appearance, duration of catheter use, culture outcomes, microbial isolates, and the distribution of diabetic versus nondiabetic subjects.

Table 3.

Summary of catheterization features, urine characteristics, culture results, and study demographics

Parameter (n=100)	Subcategory (n)	CAUTI occurrence, n (%)	P	χ 2	RR (95% CI)
Age of the patient (years)
<60	62	14 (22.58)	0.447	0.579	0.71 (0.37–1.38)
>60	38	12 (31.57)	0.006	0.579	1.4 (0.73–2.70)
Sex distribution
Male	62	12 (19.36)	0.0023	9.23	2.77 (1.43–5.37)
Female	38	14 (36.84)
Catheter care documentation
Complete	85	17 (20)	0.0032	8.63	3.00 (1.66–5.43)
Incomplete	15	9 (60)
Glycaemic status
Diabetic	28	16 (57.14)	<0.00001	18.47	4.11 (2.11–8.00)
Nondiabetic	72	10 (13.89)
Mobility status
Immobile	36	16 (44.44)	0.0014	10.18	2.84 (1.44–5.59)
Mobile	64	10 (15.62)
Body temperature
Fever with no obvious source	18	15 (83.33)	<0.00001	22.17	5.37 (2.99–9.63)
Fever with an obvious source	11	0
Normal body temperature	71	11 (15.49)
Urobag type
Open type	31	19 (61.30)	<0.00001	27.06	6.07 (2.90–12.73)
Closed type	69	7 (10.14)
Level of urobag
Above the waist	21	15 (71.43)	<0.00001	25.93	5.15 (2.79–9.49)
Below the waist	79	11 (13.92)
Kinking of urobag
No kinking	76	8 (10.53)	<0.00001	30.12	7.14 (3.58–14.23)
Kinking	24	18 (75)
Duration of catheterization
<7 days	40	4 (10)	0.0043	8.17	3.67 (1.32–10.19)
More than 7 days	60	22 (36.67)
Nature of the urine drained
Turbid	22	18 (81.82)	0.00004	16.92	3.38 (2.02–5.65)
Clear/hematuria	78	8 (10.26)
Urine culture
Positive	26	26 (100)	<0.001	71.78	72.6 (10.36–508.98)
Negative	14	0
Not needed	60	0
CAUTI organisms grown (n=26)
Escherichia coli		19 (73.08)	<0.001	32.46	OR 2.71 (1.14–6.44)‡
Klebsiella		3 (11.54)
Pseudomonas		3 (11.54)
Citrobacter		1 (3.85)
Usage of antibiotics
Received	89	18 (20.23)	<0.0001	17.24	3.60 (1.91–6.78)
Not received	11	8 (72.73)
Catheter removed within 48 h
Within 48 h	26	1 (3.85)	0.0027	8.99	0.11 (0.02–0.77)
Beyond 48 h	74	25 (33.78)

^‡OR of Escherichia coli versus other pathogens among CAUTI-positive patients; reflects distribution, not infection risk. OR: Odds ratio, CI: Confidence interval, RR: Relative risk, CAUTI: Catheter-associated urinary tract infections

Table 3 comprehensively analyses the demographic characteristics, catheterization features, urine characteristics, and culture findings concerning CAUTI incidence. Several clinical and procedural factors demonstrated statistically significant associations with infection risk (n = 100). Age was not significantly associated with CAUTI among participants aged < 60 years, with 14 out of 62 (22.6%) developing infection (P = 0.447). However, among those aged ≥60 years, 12 out of 38 (31.6%) developed CAUTI, with the difference being statistically significant (P = 0.006), indicating a possible age-related predisposition to infection. A significant sex-based difference was noted. CAUTI occurred in 12 of 62 males (19.4%) and 14 of 38 females (36.8%) (P = 0.0023). This finding suggests a differential risk profile between sexes, although further stratified analysis may be required. The presence of diabetes mellitus was strongly associated with infection. CAUTI developed in 16 of 28 diabetic patients (57.1%) compared to 10 of 72 nondiabetics (13.9%), a statistically significant difference (P < 0.00001), identifying diabetes as a significant clinical risk factor. Mobility status was also influential. Among immobile patients, 16 of 36 (44.4%) developed CAUTI versus 10 of 64 (15.6%) in the mobile group (P = 0.0014), highlighting immobility as a significant determinant of infection. Fever in the absence of an identifiable source, among those who were catheterized, was highly predictive of CAUTI, with 15 of 18 such patients (83.3%) developing infection (P < 0.00001). In contrast, no infections occurred among 11 patients with an identifiable fever source, and only 11 of 71 (15.5%) afebrile patients developed CAUTI.

Urobag type was a strong predictor. Nineteen of 31 patients (61.3%) with open drainage systems developed CAUTI, compared to 7 of 69 (10.1%) with closed systems (P < 0.00001). Similarly, urobag positioning above the waist was associated with a higher incidence (15 of 21; 71.4%) compared to below the waist (11 of 79; 13.9%) (P < 0.00001), emphasizing adherence to standard drainage practices. Kinking of the drainage tube was present in 24 patients, of whom 18 (75%) developed CAUTI, significantly higher than the 8 of 76 (10.5%) in the nonkinking group (P < 0.00001), suggesting mechanical obstruction as a preventable risk factor. Duration of catheterization was significantly associated with infection: CAUTI occurred in 22 of 60 (36.7%) patients catheterised for more than 7 days, compared to only 4 of 40 (10%) with shorter durations (P = 0.0043), reinforcing recommendations to minimize catheterization time. Urine appearance provided a predictive clinical clue. Eighteen out of 22 patients (81.8%) with turbid or purulent urine developed CAUTI compared to 8 of 78 (10.3%) with clear or hematuric urine (P = 0.00004), highlighting its diagnostic relevance. Among 40 patients for whom urine culture was sent based on clinical indication, 26 patients had positive urine culture and were diagnosed as CAUTI.

Among the 26 culture-positive CAUTI cases, Escherichia coli was the most frequently isolated organism, accounting for 19 infections (73.08%), followed by Klebsiella, Pseudomonas, and Citrobacter. An OR was calculated to understand the relative occurrence of E. coli compared to other organisms within the CAUTI group. The odds of isolating E. coli versus other pathogens among CAUTI cases were 2.71 (95% CI: 1.14–6.44), indicating that E. coli was significantly more likely to be the causative agent. However, it is essential to note that a traditional RR calculation is not appropriate in this context because all 26 patients being analyzed already had confirmed CAUTI. RR is designed to compare the probability of developing an outcome between exposed and unexposed groups in a broader population, which is not the case here. Therefore, the calculated OR reflects within-group prevalence, not risk of developing CAUTI due to E. coli.

Antibiotic usage was found to be protective against CAUTI. Among patients who received antibiotics (n = 89), only 18 (20.2%) developed CAUTI, whereas 8 of 11 patients (72.7%) who did not receive antibiotics experienced infection (P < 0.0001). This finding suggests a statistically significant protective effect associated with antibiotic prophylaxis or treatment during catheterization. Finally, catheter removal within 48 h was protective, with only 1 of 26 patients (3.8%) developing CAUTI, compared to 25 of 74 (33.8%) with delayed removal (P = 0.0027), supporting early removal as a preventative strategy. We observe a significant association between CAUTI and several patient-specific and catheter management variables, highlighting the multifactorial etiology of infection.

The type of drainage system used was strongly associated with infection risk. Despite only 31% of the study population used open-type urobags, they accounted for 73% (n = 19) of the 26 culture-positive UTI cases, and 61.3% of those with open-type urobags developed CAUTI. The distribution was statistically significant (χ² = 27.06, P < 0.00001), with patients using open-type systems having a RR of 6.07 (95% CI: 2.90–12.73) and an OR of 13.39 for developing a UTI compared to those using closed-type systems. This suggests clinical protocols prioritize closed drainage systems and actively monitor urine quality to mitigate infection risks. In this study, additional risk factors such as the level of urobag placement, kinking of catheter tubing, and the presence of diabetes mellitus were analyzed for their association with CAUTIs. Among the 100 patients, 21 had their urobag placed above the waist, while 79 had the bag appropriately positioned below waist level. Of those with urobag placement above the waist, 15 patients (71.43%) developed CAUTI. In contrast, the infection rate in those with bags below the waist was considerably lower. This association was statistically significant (χ² = 25.93, P < 0.0001), with a RR of 5.15 (95% CI: 2.79–9.49), indicating a substantially increased infection risk due to elevated bag positioning. Kinking of the urinary drainage tubing was observed in 24 patients, 18 (75%) of whom developed UTI, whereas only 8 out of 76 (10.53%) patients without kinking had UTI. This difference was highly significant (χ² = 30.12, P < 0.00001), with a RR of 7.14 (95% CI: 3.58–14.23), suggesting that tubing obstruction may significantly contribute to urinary stasis and infection. Of the 100 patients, 28 were diabetic. Among the 26 culture-positive cases of UTI, 16 occurred in diabetic patients (57.14%), while only 10 (13.89%) were from the nondiabetic group. This association was also statistically significant (χ² = 18.47, P < 0.00001), with a RR of 4.11 (95% CI: 2.11–8.00). These findings reaffirm diabetes mellitus as a significant risk factor for CAUTI. Together, these results demonstrate that improper urobag positioning, kinking of the drainage tubing, and diabetes mellitus are each independent and statistically significant predictors of CAUTI. These findings underscore the importance of adherence to proper catheter care protocols and intensified monitoring of high-risk patients to reduce infection rates.

Figure 4 illustrates how urobag type, positioning level, catheter tubing kinking, and diabetes mellitus status influence the risk of CAUTI.

Figure 4.

Association of urobag type, urobag level, tubing kinking, and diabetes mellitus with catheter-associated urinary tract infections. (a) Urobag type and urinary tract infection (UTI). (b) Urobag level and UTI. (c) Kinking of tubings and UTI. (d) Diabetes mellitus and UTI

Figure 5 illustrates the urine characteristics and distribution of antibiotic administration in the cohort and compares UTI incidence between patients who had turbid urine on catheterization with those who had clear urine or hematuria [Figure 5a], and between patients who received antibiotics and those who did not [Figure 5b].

Figure 5.

Association of urine characteristics and impact of antibiotic administration on the incidence of catheter-associated urinary tract infection. (a) Correlation between urine characteristics and urinary tract infection (UTI). (b) Correlation between antibiotic use and UTI

Among the 22 patients who presented with either turbid or purulent urine, 18 (81.8%) were diagnosed with a UTI based on positive urine cultures. In contrast, among the 78 patients whose urine was clear or hematuria, only 8 (10.3%) developed a UTI. The association between abnormal urine appearance and UTI occurrence was highly significant (χ² = 16.92, P = 0.0004), indicating that abnormal urine appearance is a strong predictive marker for CAUTI. The odds of developing UTI were 13.88 times higher in patients with turbid or purulent urine (95% CI: 3.90–49.36), and the RR was 3.38 (95% CI: 2.00–5.70), underscoring the clinical utility of routine visual inspection of urine as a simple yet effective risk assessment tool. Of the 100 catheterized patients in the study, 89 (89%) received antibiotics either as prophylaxis or treatment during their hospital stay, while 11 (11%) did not [Figure 5b]. The impact of antibiotic usage on the incidence of CAUTI was analyzed in both groups. Among the 89 patients who received antibiotics, 18 (20.2%) developed a UTI, whereas 71 (79.8%) did not. In contrast, of the 11 patients who did not receive antibiotics, 8 (72.7%) developed a UTI, and only 3 (27.3%) remained infection-free. The difference in infection rates between the two groups was highly significant (χ² = 17.24, P < 0.0001), indicating a strong association between lack of antibiotic use and increased risk of CAUTI.

Antibiotic administration was found to be a significant protective factor against CAUTI. Patients who received antibiotics had markedly lower odds of developing infection, with an OR of 0.08 (95% CI: 0.02–0.37), indicating a 92% reduction in risk compared to those who did not receive antibiotics. Conversely, when viewed from the opposite perspective, patients who did not receive antibiotics were found to have an OR of 11.81 (95% CI: 2.74–50.77), meaning they were nearly 12 times more likely to develop CAUTI than those who were appropriately treated. These findings underscore the potential protective effect of antibiotic use in high-risk patients, while also highlighting the importance of judicious antimicrobial stewardship to avoid resistance from overuse.

The RR was calculated as 3.60 (95% CI: 1.91–6.78), indicating that patients not given antibiotics were 3.6 times more likely to develop CAUTI than those who received antimicrobial coverage. These findings suggest a potentially protective effect of timely and appropriate antibiotic use in catheterized patients, particularly in high-risk cohorts. However, given the global concern over antimicrobial resistance, these results also highlight the importance of judicious antibiotic use, guided by culture sensitivity and clinical indication rather than blanket prophylaxis.

Novelty heatmap scoring was performed to evaluate the translational impact of study contributions. Each of the ten contributions was independently assessed by two reviewers across ten interdisciplinary domains using a 3–5 scale, where 3 denoted moderate novelty and 5 denoted high novelty. Any discrepancies were resolved by the consensus. Color coding in the heatmap reflects the final scores, with dark blue = 5 (high novelty), yellow = 4, and green = 3 [Figure 3].

High-impact contributions such as the CAUTI scoring system, procedural risk quantification, and ROC curve validation received the highest novelty scores (5) across nearly all domains, reflecting their cross-cutting relevance and methodological advancement. Patient risk stratification and urine turbidity validation also demonstrated high novelty in domains like infection control, nursing practice, and clinical epidemiology, where individualized risk prediction and bedside indicators hold practical significance. However, in the domain of diagnostic analytics, four contributions – including the scoring system, patient stratification, urine turbidity, and documentation gaps – received lower novelty scores (score = 3). This is because these elements relied on traditional statistical validation (e.g., ORs, ROC curves) rather than leveraging advanced analytical techniques such as machine learning, artificial intelligence modeling, or high-dimensional data analysis that typically define innovation in this domain. Antibiotic use analysis, kinking and positioning insights, and device-level interventions showed strong relevance to hospital quality assurance (QA) and safety, implementation science, and medical education. Finally, low and middle income countries (LMIC)-relevant implementation was recognized for its novelty in global health, reflecting the study’s focus on cost-effective, scalable interventions applicable to the resource-constrained settings. The heatmap highlights the interdisciplinary applicability and translational value of the proposed framework across clinical, educational, and safety-focused domains.

DISCUSSION

CAUTIs, still a significant issue in healthcare environments, add to rising morbidity, longer hospital stays, and higher healthcare expenses. Using 100 catheterized patients, this study assessed several clinical and procedural elements affecting the incidence of CAUTI, exposing important information on modifiable risk factors and preventative measures. Females are generally more susceptible to UTI due to anatomical predisposition, and our study similarly showed a higher incidence of CAUTI among females (36.8%) compared to males (19.4%). However, the absolute number of male patients who developed CAUTI (n = 12) was close to that of females (n = 14), which likely reflects the higher proportion of catheterized males in our cohort (62 out of 100). This underscores that while incidence was higher in females, the burden of infection in males was also considerable due to greater catheter exposure.

One accepted risk factor for CAUTIs is prolonged catheterization. Sixty percent of the patients in our study were catheterized for more than 7 days; this subgroup accounted for most positive urine cultures. This observation is consistent with the results of Nicolle, who found that the length of catheterization mainly determines infection with long-term indwelling catheters. According to Nicolle’s review, UTIs typically accompany biofilm development on internal and external catheter surfaces. The biofilm shields species from antibiotics and the host immune response, therefore complicating the treatment of infections.[11] Nicolle further highlights the higher danger of extended catheter use since the infection rate for short- or long-term catheters is around 5% daily. Fever from a urinary source is somewhat common in individuals with long-term catheters, ranging from 1 per 100 to 1 per 1000 catheter days. Residents of long-term care facilities with persistent indwelling catheters run a substantially higher risk of bacteremia and other urinary problems than those without catheters. These results highlight the need to shorten the length of catheterization to lower the CAUTI risk.

The results of our investigation confirm Nicolle’s conclusions that long-term catheterization dramatically raises the CAUTI risk. Preventing these infections mostly depends on rigorous adherence to catheter care guidelines and methods to reduce catheter use. With 81.8% of patients showing aberrant urine appearance testing positive for infection (P = 0.0004), our study noted a statistically significant connection between turbid or purulent urine and culture-confirmed UTI. This validates the theory that an effective bedside indication of CAUTI can be visual alterations in urine. Still, this has to be seen with clinical caution. While changes in urine appearance, such as turbidity, can be linked with infection, Hooton et al., in the IDSA guidelines for catheter-associated UTIs, underline that they are neither sensitive nor specific enough to be used in isolation for diagnostic purposes.[12] Their guidelines recommend that clinical symptoms (e.g., fever, flank pain) and laboratory evidence (e.g., pyuria, bacteriuria ≥10⁵ CFU/mL) must be used in tandem. Therefore, while our findings reinforce the visual inspection of urine as an early clue, they align with Hooton’s position that diagnosis should be guided by integrated clinical-laboratory correlation to avoid overtreatment or misdiagnosis. Furthermore, their study cautions against initiating antimicrobial therapy based solely on urine cloudiness in catheterized patients, as asymptomatic bacteriuria is common and often does not warrant treatment. This highlights the importance of antimicrobial stewardship even when the appearance of urine seems suspicious.

In our study, E. coli emerged as the predominant pathogen in CAUTIs, consistent with global epidemiological trends. Its ability to adhere to uroepithelial cells and form biofilms on catheter surfaces enhances persistence and resistance to antimicrobial agents, complicating treatment. Diabetes mellitus significantly increased CAUTI susceptibility (P < 0.00001). This elevated risk is linked to hyperglycemia-induced neutrophil dysfunction, autonomic neuropathy causing bladder stasis, and glycosuria, which provides a nutrient-rich medium for bacterial proliferation. These observations align with findings by Geerlings et al., who reported higher incidence and severity of UTIS, particularly E. coli-related, in diabetic individuals.[13] Geerlings, in yet another study, emphasizes that immune impairment and urinary tract abnormalities in diabetes contribute to increased infection risk.[14] Our results underline the need for aggressive urine treatment and careful monitoring for catheterized diabetic patients in order to lower the load of CAUTI.

In our investigation, a higher incidence of CAUTI was strongly correlated with particular device-related characteristics. The usage of open-type urobags, location of the urobag above the waist level, and kinking of catheter tubing were particularly independently associated with greater infection rates. The ORs underlined even more the degree of these correlations: patients with kinked catheter tubing had an OR of 18.7 for UTI development, while those with high urobags had an OR of 12.67. These results expose important flaws in the methods of catheter care. Because they expose open drainage systems to the outside world, they can help to enable retrograde bacterial movement. In the same vein, elevating the urobag above the bladder can hinder appropriate drainage, resulting in urine stasis–a recognized risk factor for bacterial colonization. Kinking of the catheter tubing can block urine flow, therefore fostering the growth of bacteria in a suitable habitat.

Gould et al., under their thorough recommendations for avoiding CAUTI, stress the need to keep a closed drainage system and guarantee unhindered urine flow.[15] To stop urine backflow, which can infect the urinary system, they advise that the drainage bag always be held below bladder level. They also underline the need to keep the catheter secure to stop movement and possible kinking, compromising the closed system’s integrity and raising the infection risk. The results of our research support the recommendations made by Gould et al., therefore underlining the need to follow best standards in catheter management.[15] The important correlations found between device-related factors and CAUTI incidence in our cohort highlight the need for thorough training for medical staff, frequent audits of catheter care procedures, and quick corrective action when deviations from accepted guidelines are found. Using standardized care bundles with these guidelines will help to significantly lower CAUTI incidence. Protocols for aseptic catheter insertion, management of a closed drainage system, correct drainage bag positioning, and frequent catheter and tubing cleaning or obstruction inspection should all be part of such bundles. Reducing these controllable risk factors would help healthcare institutions improve patient safety and lower the load of catheter-associated infections.

While our study observed a statistically significant protective effect of antibiotic administration against CAUTI (OR 0.08), with patients who did not receive antibiotics showing 11.8-fold greater risks of acquiring UTI (P < 0.0001), this finding must be interpreted within the broader framework of antimicrobial stewardship. International guidelines, including those of the IDSA, caution against routine or blanket prophylaxis in catheterized patients because of the risk of fostering antimicrobial resistance and unnecessary treatment of asymptomatic bacteriuria. Marschall et al. in their meta-analysis similarly demonstrated that although prophylaxis may transiently reduce bacteriuria after catheter removal, indiscriminate use is not recommended.[16] Our results, therefore, support a more selective approach: antibiotics may be justified in high-risk patients identified by our risk scoring system, but standard preventive measures–such as aseptic catheter insertion, maintenance of a closed drainage system, early removal, and adherence to care bundles–must remain the cornerstone of CAUTI prevention. Balancing efficacy with resistance reduction depends on combining tailored antibiotic regimens with infection control measures. The multifactorial nature of CAUTI risk, encompassing patient comorbidities, catheter care practices, and preventive strategies, underscores the need for comprehensive infection control programs. The results advocate for institutional reinforcement of aseptic catheterization protocols, prompt urine evaluation, and risk stratification, particularly in diabetic and long-term catheterized patients. Future research should consider prospective interventional studies assessing the impact of training modules and standardized care bundles on reducing CAUTI incidence.

Recent literature further substantiates the multifactorial risk model demonstrated in our study. Our observation that older age, female sex, and prolonged catheterization increase CAUTI susceptibility aligns with the findings of Rosenthal et al. (2024), who conducted a large-scale international prospective study across 235 intensive care units (ICUs) in eight Asian countries.[17] They identified significantly higher CAUTI rates in older patients and females. Similar investigations verified a closer link between CAUTI in trauma and patients of the neurologic ICU.[18,19] Their research notably revealed a higher risk in public healthcare environments and in patients using suprapubic catheters, directing our focus on institutional and device-related factors causing infection burden.

ICUs still have a major problem with CAUTIs.[20,21] Given higher risks noted among female patients and those with internal medical conditions, this is particularly troublesome. In a multicentric ICU study covering 37 countries, Jin et al. noted greater CAUTI incidence in public sector hospitals and middle-income countries.[22] This relates to our results on procedural errors, such as faulty bag placement and open urobag systems, which would be more common in low-resource areas. These common opinions underline the pressing need for focused intervention programs aiming at context-specific healthcare issues. Machine learning models can predict the risk of CAUTI in patients with device-associated infections.[23] Our findings on duration-dependent risk and patient-specific susceptibility are echoed by Liu et al. (2023) who developed a predictive model for CAUTI in neurosurgical ICU patients. Their decision tree identified age ≥60, female sex, and catheterisation for 7–14 days as key predictors–factors significantly reflected in our cohort.[24] This supports the feasibility of using patient-level data to stratify CAUTI risk proactively.

Furthermore, our emphasis on device-related modifiable risks, such as kinking and drainage positioning, is reinforced by Calpe–Damians et al., who demonstrated that using a catheter securement device significantly reduced CAUTI rates and catheter-related skin complications. Their findings underscore the potential for simple yet effective device-level innovations to improve outcomes, complementing our advocacy for strict adherence to catheter care protocols.[25] Together, these recent studies strengthen the external validity of our findings and illustrate the importance of integrating clinical vigilance, localized policy frameworks, and procedural innovation in CAUTI prevention strategies.

In support of the proposed CAUTI risk scoring system, a ROC curve analysis yielded an impressive AUC of 0.94, denoting excellent discriminatory performance. This reinforces the scoring model’s ability to differentiate reliably between patients at low versus high risk of developing CAUTI. Furthermore, the score distribution analysis revealed that most CAUTI-positive patients clustered at cumulative scores ≥7, justifying this threshold as a clinically meaningful inflexion point for early intervention. The clear separation between CAUTI-positive and CAUTI-negative subgroups across the scoring spectrum underscores the internal validity of the model. A similar approach was demonstrated by Li et al., who developed a predictive model for CAUTI in neurosurgical ICU patients using multivariate decision-tree algorithms and reported an AUC of 0.90, validating the utility of composite risk profiling in clinical triage.[26] Zhou et al. conducted a propensity score-matched study to identify predictors of CAUTIs in women undergoing radical hysterectomy for cervical cancer. They developed a nomogram incorporating catheter duration and urine culture status, demonstrating strong discriminatory capacity with an AUC of 0.9035. Their findings support using individualized risk models to enhance CAUTI prevention in postoperative surgical settings.[27] Our tool demonstrated predictive strength and practical applicability by integrating procedural, patient-specific, and early clinical indicators into a unified scoring matrix. These findings affirm the utility of the risk scoring framework as a triage instrument for tailoring catheter care intensity and guiding preventive strategies in real time.

To contextualize the cross-domain applicability of our findings, a visual heatmap was generated, mapping ten unique contributions of the study against ten major research domains. This qualitative matrix highlights each contribution’s translational breadth and relative novelty intensity, enabling a broader interpretation of its impact beyond traditional urological or infection-specific paradigms. Our approach is conceptually aligned with the work of Baumgartl et al. (2021), who employed visual analytics, including heatmaps and temporal matrices, to trace pathogen transmission pathways within hospital networks.[28] Their study emphasized the value of multidimensional visual tools in identifying overlooked infection routes, strengthening real-time surveillance, and supporting infection control decisions. Similarly, our use of heatmap-based novelty scoring underscores the role of visual frameworks in conveying complex, multi-domain contributions and guiding clinical prioritization and policy alignment for catheter-associated infection prevention.

Our findings align with global multicentric data. Rosenthal et al. reported sex-specific CAUTI variation across 235 ICUs in Asia, while Jin et al. identified similar risk factors in a middle eastern cohort.[17,22] Sleziak et al. further highlighted CAUTI trends in post-COVID ICUs, and Calpe–Damians et al. demonstrated reduced infection rates with catheter securement devices.[20,25] Together, these large-scale studies reinforce the external validity and international applicability of our scoring system.

Unique considerations

This study presents a novel, point-based risk scoring system for CAUTI, distinguished by its integrative approach across procedural, clinical, and early diagnostic domains. This is the first prospective effort to statistically validate such a multidimensional model, demonstrating high predictive capability (AUC = 0.94) and offering a defensible cut-off score of ≥7 for high-risk stratification. Unlike prior research on isolated risk factors, our model synthesizes five procedural variables, patient comorbidities, and clinical cues such as urine turbidity into a unified predictive framework. The study further bridges gaps in existing literature by empirically linking caregiver knowledge deficits to patient outcomes, establishing the first documented correlation between staff training lapses and increased CAUTI incidence. The structured staff questionnaires and protocol compliance evaluations used in this study support the operational relevance of guideline implementation in real-world clinical environments. Notably, our validation of visual urine characteristics, particularly turbid or purulent appearance, as statistically significant predictors of CAUTI (P = 0.00004; OR = 13.88), redefines bedside assessment protocols by transforming subjective observations into evidence-backed diagnostic cues.

To visually contextualize the breadth of these contributions, we employed a heatmap [Figure 3] that quantifies the novelty score of each contribution across 10 relevant domains. The scoring system, procedural quantification, and urine-based clinical indicators received the highest novelty score of 5, reflecting their innovation and clinical applicability. The heatmap emphasizes the study’s impact across multiple research axes – including procedural standardization, microbial epidemiology, system-level application in LMIC settings, and clinical triage analytics – thus reinforcing its translational potential. This study represents one of the first prospective single-center Indian audits to integrate real-time procedural monitoring, caregiver compliance, and microbiological profiling, providing a comprehensive framework for CAUTI risk stratification. Including antibiotic stewardship and early catheter removal as protective variables enhances the model’s practical relevance and aligns with infection prevention priorities in resource-constrained healthcare systems.

This research introduces a robust, data-driven CAUTI risk scoring system and provides a replicable model for cross-domain integration in infection prevention research. Its methodological rigor, visual analytics, and empirical validation collectively offer a scalable early CAUTI identification and prevention solution in diverse clinical settings.

Limitations of the study

This study was conducted at a single tertiary care academic center with a sample size of 100 patients, which inherently limits the external generalizability of our findings. Although the relatively small, single-center design may not capture heterogeneity across diverse healthcare systems, the prospective methodology and real-world setting strengthen its clinical relevance. Notably, the CAUTI risk scoring system demonstrated excellent internal validation (AUC 0.94), reinforcing its predictive strength within this cohort. Our findings provide region-specific insights from an Indian tertiary referral hospital, complementing global evidence. Nevertheless, these results should be regarded as hypothesis-generating, and larger multicentric studies across varied settings are required to validate and refine the scoring system before widespread implementation externally. Urine cultures were performed only when clinical suspicion arose; therefore, the true incidence of asymptomatic bacteriuria may have been underestimated. Nevertheless, this methodology aligns with the international guidelines that discourage indiscriminate urine culturing, ensuring that our findings represent clinically relevant CAUTI rather than colonization.

CONCLUSIONS

This prospective and observational study highlights that modifiable procedural and patient-related factors significantly influence CAUTI. Open drainage systems, improper urobag positioning, tubing kinking, and absence of prophylactic antibiotics were independently associated with higher infection rates. Diabetic status and catheterization beyond 7 days further amplified infection risk. Notably, turbid or purulent urine and unexplained fever emerged as early predictive markers of CAUTI. Although antibiotic administration was associated with a protective effect against CAUTI in our cohort, its role should be viewed as adjunctive and selective rather than routine. Guided by antimicrobial stewardship principles, antibiotics should be reserved for high-risk patients and always tailored to culture and sensitivity results. At the same time, core preventive strategies – early catheter removal, aseptic technique, and closed drainage maintenance – must remain the foundation of CAUTI prevention.

The study also introduced a novel, clinically applicable CAUTI risk scoring system, enabling real-time risk stratification and targeted intervention. These findings reinforce the critical role of standardized catheter care protocols, staff training, and early risk assessment in minimizing CAUTI incidence. As one of the largest prospective audits from an Indian academic center, this study provides regionally relevant data with global applicability. Future interventional studies should explore implementing bundled care strategies and risk-based surveillance to further reduce the burden of CAUTI.

Ethical approval

Approval for this study was obtained from the Institutional Review Board.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.