Clinical Characteristics of Fever without Localizing Sign in Infants Younger than 100 Days of Age in a Single Center

ABSTRACT

PURPOSE: This study was done to define clinical characteristics of fever without localizing signs (FWLS) in infants younger than 100 days of age with a goal of providing baseline data to establish a new diagnostic paradigm in the future. METHODS: We reviewed medical records of 183 patients who admitted to Daegu Catholic University Medical Center for FWLS younger than 100 days of age from January 2013 to September 2015 retrospectively. Demographic, clinical features and laboratory findings were analyzed. Patients were divided into serious bacterial infection (SBI) and non-SBI groups, and then were compared between two groups to find risk factors for SBI. RESULTS: Among 183 patients, lumbar puncture was performed in 98.9% and CSF pleocytosis was present in 35.9%. Sterile CSF pleocytosis was found in 43% of urinary tract infection (UTI) patients. None had concomitant bacterial meningitis in patients with UTI. As final diagnosis, febrile syndrome without source (25.7%) was most common. Among SBI, UTI was most common (99%). Birth weight, ESR, and CRP were significantly higher in SBI group compared to non-SBI group. Male sex (OR 4.93, 95% CI 1.60-15.24) and pyuria (OR 18.88, 95% CI 6.76-52.76) were identified as risk factors for SBI. Presence of sibling (OR 0.30, 95% CI 0.11-0.83) was significantly lower in SBI group. CONCLUSIONS: Our results showed UTI was the most common SBI in young infants with FWLS. Though aseptic meningitis can be coexisting with UTI, lumbar puncture may not be necessary in all patients having UTI.