Clinical course of urinary tract infections in infants younger than 60 days of age

Abstract

Objectives: Although often managed differently than older children, no study has specifically described the clinical course of urinary tract infections (UTIs) in young infants. Our objective was to determine the risk of progression of illness and the pattern of fever resolution in infants younger than 60 days of age with Gram-negative rod UTIs.

Methods: We completed a retrospective medical chart review. Patients younger than 60 days of age presenting to an urban, tertiary care pediatric hospital were included if they had single organism growth of Gram-negative rods in any amount from suprapubic aspiration samples or more than 10,000 cfu/mL from catheterized specimens. Significant progression of illness was defined as the need for transfer to an intensive care setting. Fever was defined as a rectal temperature of 38.0 degrees C or higher or an axillary temperature 37.0 degrees C or higher. Temperatures were assigned to blocks of 4 hours.

Results: Of 128 patients with available records, none were transferred from the general pediatric ward to the intensive care unit and 2 were transferred to a step-down unit for events potentially unrelated to the UTI. No patient had a positive repeat urine culture. For patients with fever, median time to fever resolution was within the 4 to 8 hour time block. Eighty-five percent of the febrile patients became afebrile within 24 hours and only 3.6% were febrile after 48 hours.

Conclusions: Progression of illness in infants with Gram-negative rod UTIs is unlikely. Fever resolution is rapid. If subsequent studies concur with our findings, outpatient therapy or short-stay unit admission may become a viable management strategy.