Urine dipstick low sensitivity for UTI diagnosis in febrile infants*

Prevalence, aetiology, antimicrobial susceptibility testing, and predictors of urinary tract infection among neonates with clinical sepsis: a cross-sectional study

Background

Urinary tract infection (UTI) is the most common and life-threatening bacterial infection among neonates. This study aimed to determine the prevalence, aetiology, and susceptible antimicrobial agents among neonates with UTI.

Methods

This was a cross-sectional analytical hospital-based study that included 152 neonates with clinical sepsis who were admitted at Dodoma regional referral hospital from January to June 2020. Bacterial growth of 1 × 103 colony forming units/mL of a single uropathogen was used to define the presence of UTI. Statistical analysis was performed using SPSS version 23.0 and multivariate analysis was used to determine the predicting factors of UTI. P <0.05 was regarded statistically significant.

Results

The prevalence of UTI was 18.4% (28/152). Klebsiella pneumoniae 64.3% (18/28) and Enterobacter spp. 35.7% (10/28) were the bacterial agents isolated. The bacterial isolates were 90%, and 60% sensitive to ciprofloxacin and amikacin, respectively. Low Apgar score (AOR = 12.76, 95% CI = 4.17–39.06, p<0.001), prolonged labour (AOR = 5.36, 95% CI = 1.28–22.52, p = 0.022), positive urine nitrite test (AOR = 26.67, 95% CI = 7.75–91.70, p<0.001), and positive leucocyte esterase test (AOR = 6.64, 95% CI = 1.47–29.97, p = 0.014) were potential predictors of UTI.

Conclusion

The prevalence of UTI confirmed by urine culture among neonates that were included in the present study indicates that this problem is common in the population where the study was conducted. Klebsiella pneumoniae and Enterobacter spp. were the uropathogens which were isolated. Ciprofloxacin, nitrofurantoin, and amikacin were sensitive to the isolated uropathogens.

High Rates of Antibiotic Nonsusceptibility in Gram-negative Urinary Tract Infection in Children With Risk Factors Occurring in the Preceding Month: Considerations for Choosing Empiric Treatment

BACKGROUND

Choosing an empiric treatment for urinary tract infections (UTIs) requires epidemiologic data on antibiotic nonsusceptibility (ANS) rates, and risk factors for UTI and ANS in the individual patient. We assessed ANS in community-acquired UTI, and its association with risk factors exposure (previous antibiotic treatment, UTI and hospital visit) <1 month or 1-11 months before the current UTI episode.

METHODS

This was a retrospective, cohort study. Children <2 years with hospital visits and a positive urine culture obtained <48 hours from hospital admission whose culture yielded Gram-negative bacteria during the years 2015-2016, were included.

RESULTS

Of the overall 744 episodes, 80% were Escherichia coli. Overall ANS rates were 66% for ampicillin; 27%-29% for amoxicillin/clavulanic acid, cephalosporins (indicating extended-spectrum beta-lactamase) and trimethoprim-sulfamethoxazole; 14% for nitrofurantoin; 5%-6% for gentamicin, ciprofloxacin and piperacillin/tazobactam; and <1% for meropenem and amikacin. Higher ANS rates were associated with Bedouin (vs. Jewish) ethnicity, exposure to risk factors <1 month, and to a lesser extent during the 1-11 months before the studied UTI episode. In episodes with risk factors <1 month, ANS rates were 81% for ampicillin; 47%-58% for amoxicillin/clavulanic acid, cephalosporins and trimethoprim-sulfamethoxazole; 19% for nitrofurantoin; 12%-23% for gentamicin, ciprofloxacin and piperacillin/tazobactam; and 2% for meropenem and amikacin.

CONCLUSIONS

Previous antibiotic treatment, hospital admission and UTI, especially <1 month before the current episode, and Bedouin ethnicity, were all associated with high rates of ANS. These findings are important and may assist the treating physician in choosing an adequate empiric treatment for UTI.

Catheter-obtained, Enterococcus and Proteus positive urine cultures may represent mostly contamination or asymptomatic bacteriuria in infants <90 days

BACKGROUND

Urinary tract infection (UTI) diagnosis in infants is often made by a positive urine culture result, regardless of urine dipstick findings.

AIM

To assess parameters that may affect positive urine culture results interpretation in infants, including dipstick performance, obtainment method, bacteria type, age and laboratory results.

METHODS

A retrospective, cohort study. Infants <90 days with urine dipstick and culture obtained through subrapubic aspiration (SPA) or catheter, 2015-2016, were included.

RESULTS

Overall, 19% (129/678) of cultures were positive. The dipstick sensitivity was 51% for all cultures; 66%, 47%, 15% and 10% for Escherichia coli (n= 71), Klebsiella (n= 19), Enterococcus (n= 34) and Proteus (n= 10), respectively (p<.001). Sensitivity was higher in SPA vs. catheter for all cultures (67% vs. 43%); E. coli (78% vs. 59%); and Klebsiella (88% vs. 18%). For Enterococcus, dipstick sensitivity was low in both SPA and catheter (0-16%). All Proteus episodes were catheter obtained. Positive culture with negative dipstick and Enterococcus episodes had lower C-reactive protein levels, and higher proportion of mixed infection compared with positive dipstick and E. coli episodes.

CONCLUSIONS

Urine cultures in infants should be obtained by SPA, since catheter-obtained, Enterococcus and Proteus positive cultures may represent contamination or asymptomatic bacteriuria, rather than true UTI.

Catheter-Obtained Urine Culture Contamination Among Young Infants: A Prospective Cohort Study

Objectives: A correct diagnosis of urinary tract infection in young infants requires an uncontaminated urine culture, commonly obtained by urethral catheterization. In the current study, we examined the rates and factors associated with contaminations of catheter-obtained urine cultures in very young infants. Methods: This prospective cohort study included 143 catheter-obtained urine cultures of infants ≤2 months of age admitted to the pediatric ward of a tertiary hospital in Israel from April 2019 to September 2020. Patient's and operator's study variables were documented at the time of catheter insertion. Positive urine cultures were reviewed by a pediatric nephrologist and a pediatric infectious disease specialist and designated as infection or contamination. The study variables were compared between those with or without contamination. Results: The contamination rate in our cohort was 29%. Females were more than twice as likely to have a contaminated urine culture (37 vs. 18%, respectively, P = 0.014). Circumcision status, official training about sterile catheterization, a sense of difficult catheterization, and the shift in which the culture was obtained did not influence the contamination rate. Conclusions: Catheter-obtained urine cultures have a high contamination rate among very young infants, especially among girls.