CONTEXT: Urinary tract infections (UTIs) are common in young infants, yet there is no guidance on the optimal duration of intravenous (IV) treatment. OBJECTIVE: To determine if shorter IV antibiotic courses (≤7 days) are appropriate for managing UTIs in infants aged ≤90 days. METHODS: PubMed, the Cochrane Library, Medline, and Embase (February 2021) were used as data sources. Included studies reported original data for infants aged ≤90 days with UTIs, studied short IV antibiotic durations (≤7 days), and described at least 1 treatment outcome. The Preferred Reporting Items for Systematic Reviews and Meta-analyses guideline was followed. Studies were screened by 2 investigators, and bias was assessed by using the Newcastle-Ottawa Scale and the Revised Cochrane Risk-of-Bias Tool. RESULTS: Eighteen studies with 16 615 young infants were included. The largest 2 studies on bacteremic UTI found no difference in the rates of 30-day recurrence between those treated with ≤7 vs >7 days of IV antibiotics. For nonbacteremic UTI, there was no significant difference in the adjusted 30-day recurrence between those receiving ≤3 vs >3 days of IV antibiotics in the largest 2 studies identified. Three studies of infants aged ≥30 days used oral antibiotics alone and reported good outcomes, although only 85 infants were ≤90 days old. CONCLUSIONS: Shorter IV antibiotic courses of ≤7 days and ≤3 days with early switch to oral antibiotics should be considered in infants aged ≤90 days with bacteremic and nonbacteremic UTI, respectively, after excluding meningitis. Further studies of treatment with oral antibiotics alone are needed in this age group.

ObjectiveShorter courses of intravenous antibiotics for young infants with urinary tract infection (UTI) have myriad advantages. As practice shifts toward shorter intravenous treatment courses, this study aimed to determine the safety of early intravenous-to-oral antibiotic switch and identify risk factors for bacteraemia with UTI.MethodsRetrospective audit of infants aged ≤90 days with a positive urine culture at a quaternary paediatric hospital over 4 years (2016–2020). Data were collected from the hospital electronic medical record and laboratory information system. Short-course intravenous antibiotic duration was defined as <48 hours for non-bacteraemic UTI and <7 days for bacteraemic UTI. Multivariate analysis was used to determine patient factors predicting bacteraemia.ResultsAmong 427 infants with non-bacteraemic UTI, 257 (60.2%) were treated for <48 hours. Clinicians prescribed shorter intravenous courses to infants who were female, aged >30 days, afebrile and those without bacteraemia or cerebrospinal fluid pleocytosis. Treatment failure (30-day UTI recurrence) occurred in 6/451 (1.3%) infants. All had non-bacteraemic UTI and one received <48 hours of intravenous antibiotics. None had serious complications (bacteraemia, meningitis, death). Follow-up audiology occurred in 21/31 (68%) infants with cerebrospinal fluid pleocytosis, and one had sensorineural hearing loss. Bacteraemia occurred in 24/451 (5.3%) infants, with 10 receiving <7 days intravenous antibiotics with no treatment failure. Fever and pyelonephritis were independent predictors of bacteraemia.ConclusionShort-course intravenous antibiotics for <48 hours for young infants with non-bacteraemic UTI should be considered, provided meningitis has been excluded. Treatment failure and serious complications were rare in young infants with UTI.

Background Shorter courses of intravenous (IV) antibiotics for young infants with urinary tract infection (UTI) have myriad advantages. As practice shifts toward shorter IV treatment course, this study aimed to determine the safety of early IV-to-oral antibiotic switch, and identify risk factors for bacteraemia with UTI. Methods Retrospective audit of infants aged ≤90 days with a positive urine culture at a quaternary paediatric hospital over four years (2016-2020). Data were collected from the hospital electronic medical record and laboratory information system. Short-course IV antibiotic duration was defined as &lt; 48 hours for nonbacteraemic UTI and &lt; 7 days for bacteraemic UTI. Multivariate analysis was used to determine patient factors predicting bacteraemia. Results Among 427 infants with nonbacteraemic UTI, 257 (60.2%) were treated for &lt; 48 hours. Clinicians prescribed shorter IV courses to infants who were female, aged &gt;30 days, afebrile, and those without bacteraemia or cerebrospinal fluid pleocytosis. Treatment failure (30-day UTI recurrence) occurred in 6/451 (1.3%) infants. All had nonbacteraemic UTI and only one received &lt; 48 hours of IV antibiotics. None had serious complications (bacteraemia, meningitis, death). Follow-up audiology was performed in 21/31 (68%) infants with cerebrospinal fluid pleocytosis, and one had sensorineural hearing loss. Bacteraemia occurred in 24/451 (5.3%) infants, with 10 receiving &lt; 7 days IV antibiotics with no treatment failure, meningitis or death. Fever and pyelonephritis were independent predictors of bacteraemia. Conclusion Short course IV antibiotics for &lt; 48 hours for young infants with nonbacteraemic UTI are safe provided bacterial meningitis has been excluded. Treatment failure and serious complications were rare in young infants with UTI. Disclosures All Authors: No reported disclosures