Validity of urinary catheter specimen for diagnosis of urinary tract infection in the elderly

Twenty elderly nursing home patients with long-term indwelling bladder catheters were studied to evaluate the validity of the microbiology of urine samples obtained from catheters that had not been changed for at least 30 days. Paired urine samples from "old" catheters and newly inserted catheters were compared for quantitative and qualitative microbiology. Urine microbiology for old catheters was highly sensitive but had poor specificity.     

Antibiotic prophylaxis after extraction of urinary catheter prevents urinary tract infections: A systematic review and meta-analysis

ObjectiveTo investigate the effect of antibiotic prophylaxis for consequent urinary tract infections (UTIs) after extraction of urinary catheter and further explore the association between the outcome and clinical characteristics of patients.MethodsWe systematically searched PubMed, Cochrane Library, EMBASE, and ClinicalTrials.gov databases through March 2020. Studies were included if they inquired into antibiotic prophylaxis for UTIs after extraction of a temporary (≤14 days) urinary catheter. We used fixed-effect models to obtain pooled risk ratio (RR) estimates. Heterogeneity was evaluated with I² value. Sensitivity analysis and subgroup analysis were also conducted to assess heterogeneity.ResultsWe finally included 8 randomized controlled trials in our study. Only 2 studies showed that antibiotic prophylaxis can reduce the consequent UTIs after extraction of urinary catheters while 6 did not. Overall, antibiotic prophylaxis was associated with reduced UTIs (RR, 0.47, 95% confidence interval [CI] 0.28-0.72, P< .01, I² = 31%). Subgroup analysis indicated that patients who are older than 60 (RR = 0.50, 95% CI: 0.33-0.76, P< .05, I² = 29%) or received Trimethoprim/sulfamethoxazole (TMP/SMX; RR = 0.21, 95% CI: 0.09-0.48, P< .01, I² = 0%) or indwelling catheters for more than 5 days (RR = 0.34, 95% CI: 0.19-0.63, P< .01, I² = 0%) could get more benefit from antibiotic prophylaxis after extraction of catheters.ConclusionsPatients with catheters removed might get benefit from antibiotic prophylaxis as a result of fewer consequent UTIs, and those who have advanced age (over 60 years old) or long-term catheterization (over 5 days) could get more benefit from prophylaxis. And TMP/SMX could be a good choice of prophylaxis for UTIs after extraction of urinary catheters. This approach should apply to high-risk patients (advanced age or long-term catheterization) due to the potential harm of widespread antibacterial agents such as side effects and bacterial resistance.     

Measurement of accidental urinary insulin loss from a dislocated intraperitoneal insulin catheter

We report the case of a type-2 diabetic woman who received continuous intraperitoneal insulin infusion and developed deterioration of metabolic control by accidental insulin loss into urine (54 U per day) as a consequence of catheter migration which probably resulted in bladder wall injury. Due to iodine allergy of this patient, an analyte addition procedure for insulin quantification in urine had to be applied to allow proof of insulin loss from the catheter tip before as well as reversal to zero insulin excretion after implantation of a new intraperitoneal port and a shorter catheter. The lost fraction of insulin accounted nearly completely for the difference between pre- and postoperatively required insulin doses (146 versus 88 U per day).