Imaging studies for childhood urinary infections

Characteristics of first urinary tract infection with fever in children: a prospective clinical and imaging study

BACKGROUND

Our objective is to provide the clinical characteristics, uropathogen frequencies, and antimicrobial resistance rates of first urinary tract infection (UTI) diagnosed in febrile Belgian children. The ability of noninvasive ultrasound to detect renal abnormalities and vesicoureteral reflux (VUR) in these patients was also assessed.

METHODS

We prospectively followed (median, 20 months) 209 children treated for first febrile UTI. Renal ultrasound (US) and voiding cystourethrography examinations were performed in all patients.

RESULTS

Among these children, 63% were females and 37% were males, and 75% of them had their first UTI before the age of 2 years. The most common causative agent was Escherichia coli (91% of cases) with high rate resistance to ampicillin (58%) and trimethoprim/sulfamethoxazole (38%). Of these children, 25% had evidence of VUR (15 boys and 38 girls). VUR was of low grade in 85% of cases. The overall performance of renal US as a diagnostic test to detect significant uropathies excluding low-grade VUR was excellent; the sensitivity attained 97% and the specificity 94%.

CONCLUSION

Girls represent 63% of cases with first UTI. For 91% of UTIs, Escherichia coli is held responsible with a high rate of resistance to ampicillin and trimethoprim/sulfamethoxazole. US is an excellent screening tool that allows avoidance of unjustified voiding cystourethrography studies.

Clinical decision rules in radiology

Clinical decision rules to guide physicians in the appropriate use of diagnostic imaging studies need to be developed, in part, to control the overutilization of imaging studies. These rules need to be evidence based. Randomized control trials can be designed to assess the value of imaging studies and interventional procedures at levels five and six, patient outcome and societal efficacies, in Fryback and Thornbury's hierarchical model of efficacy. Results of these trials can be used to develop clinical decision rules. However, the efficacy of most diagnostic imaging studies can be assessed better at levels three and four, diagnostic thinking and therapeutic efficacies. Studies can be designed to determine clinical situations in which imaging studies will be of no value or to determine clinical criteria for the use of imaging studies. Systematic reviews of the literature and other techniques of analysis of evidence, such as decision trees, also can be used to develop evidence-based clinical decision rules for the use of diagnostic imaging procedures.

Compliance with guidelines for the medical care of first urinary tract infections in infants: a population-based study

BACKGROUND

No population-based studies have examined the degree to which practice parameters are followed for urinary tract infections in infants.

OBJECTIVE

To describe the medical care of children in their first year of life after a first urinary tract infection.

METHODS

Using Washington State Medicaid data, we conducted a retrospective cohort study of children with a urinary tract infection during their first year of life to determine how many of these children received recommended care based on the most recent guidelines from the American Academy of Pediatrics. Recommended care included timely anatomic imaging, timely imaging for reflux, and adequate antimicrobial prophylaxis. Multivariate logistic-regression models were used to evaluate if hospitalization for first urinary tract infection, young age at time of diagnosis, gender, race, primary language of parents, having a managed care plan, and rural location of household residence were associated with recommended care.

RESULTS

Less than half of all children diagnosed with a urinary tract infection in their first year of life received the recommended medical care. Children who were hospitalized for their first urinary tract infection were significantly more likely than children who were not hospitalized to receive anatomic imaging (relative risk [RR]: 1.38; 95% confidence interval [CI]: 1.20-1.57) and imaging for reflux (RR: 1.62; 95% CI: 1.34-1.90).

CONCLUSIONS

There is poor compliance with guideline-recommended care for first urinary tract infections in infants in a Medicaid population. Given the trend toward increased outpatient management of urinary tract infections, increased attention to outpatient imaging may be warranted.