When a febrile infant in your practice is under three months of age and is hospitalized with what turns out to be a bacterial urinary tract infection (UTI), how long do you treat that infant with intravenous antibiotics? On what basis do you set the duration of treatment course? Does the presence or absence of bacteremia with the UTI influence the treatment course? These are questions Hikmat et al (10.1542/peds.2021-052466) evaluate in this systematic evidence review. The authors evaluated 18 relevant studies—2 randomized controlled trials and 16 retrospective studies involving a total of over 16,000 patients.
The authors categorized the patients in these 18 studies based on the presence of bacteremia, duration of antibiotics, and 30-day UTI recurrence. The risk of recurrence did not matter if antibiotics were used for a mean/median of <=7 days or > 7 days in the setting of bacteremia and for a mean/median of <= 3 days or > 3 days if there was no bacteremia associated wtih the UTI. They also note 3 studies of infants 1-3 months of age who only received oral antibiotics who did well. However, the number of infants in these studies was small (85).
The authors provide a great description of the findings from the studies compiled in this review. The discussion section of their review addresses the strengths as well as the limitations of the systematic review, including differences in the definition of UTI. Nonetheless, the findings do suggest shorter courses of intravenous antibiotics are worth considering assuming an infant with a UTI is well-appearing and not showing signs of sepsis or meningitis. Although this article suggests that treating infants 1-3 months with only oral antibiotics is safe, more research is needed.