BACKGROUND:Physicians often obtain a routine renal bladder ultrasound (RBUS) for young children with a first febrile urinary tract infection (UTI). However, few children are diagnosed with serious anatomic anomalies, and opportunity may exist to take a focused approach to ultrasonography. We aimed to identify characteristics of the child, prenatal ultrasound (PNUS), and illness that could be used to predict an abnormal RBUS and measure the impact of RBUS on management. METHODS:We conducted a single-center prospective cohort study of hospitalized children 0 to 24 months of age with a first febrile UTI from October 1, 2016, to December 23, 2018. Independent variables included characteristics of the child, PNUS, and illness. The primary outcome, abnormal RBUS, was defined through consensus of a multidisciplinary team on the severity of ultrasound findings important to identify during a first UTI. RESULTS:A total of 211 children were included; the median age was 1.0 month (interquartile range 0-2), and 55% were uncircumcised boys. All mothers had a PNUS with 10% being abnormal. Escherichia coli was the pathogen in 85% of UTIs, 20% (n 5 39 of 197) had bacteremia, and 7% required intensive care. Abnormal RBUS was found in 36% (n 5 76 of 211) of children; of these, 47% (n 5 36 of 76) had moderately severe findings and 53% (n 5 40 of 76) had severe findings. No significant difference in clinical characteristics was seen among children with and without an abnormal RBUS. One child had Foley catheter placement, and 33% received voiding cystourethrograms, 15% antibiotic prophylaxis, and 16% subspecialty referrals. CONCLUSIONS:No clinical predictors were identified to support a focused approach to RBUS examinations. Future studies should investigate the optimal timing for RBUS.

For children hospitalized with SSSS, lower use of diagnostic tests was not associated with changes in outcomes. Hospitals with high diagnostic test use may be able to reduce testing without adversely affecting patient outcomes.

Multisystem inflammatory syndrome in children (MIS-C) is an emerging disease described in children in association with infection or epidemiological link to severe acute respiratory syndrome coronavirus 2. Signs and symptoms include fever, rash, and cardiac dysfunction; US Centers for Disease Control and Prevention have put forth broad criteria for diagnosis. The illness is serious and can progress rapidly to heart failure and death. However, findings in MIS-C are nonspecific, and there is significant overlap with other systemic illnesses, including Kawasaki disease and several viral and bacterial infections. We present 5 children admitted to a teaching hospital within an 11-day period in May 2020 for MIS-C evaluation who were later diagnosed with murine typhus. Typhus is a rickettsial infection that presents with fever and rash, and, although usually self-limited, responds well to treatment with doxycycline to shorten the course of illness. Clinical and laboratory characteristics of these children are presented to illustrate similarities to MIS-C, which can also be shared with viral, bacterial, or other regional endemic infections, as well as noninfectious inflammatory diseases. This case series serves to remind pediatric hospitalists to be vigilant to avoid premature closure on MIS-C for children admitted with fever and systemic inflammation. Maintaining a wide differential diagnosis in approaching such patients is of utmost importance as community exposure to severe acute respiratory syndrome coronavirus 2 is likely and evidence of past infection becomes commonplace.