Murine Typhus in 5 Children Hospitalized for Multisystem Inflammatory Syndrome in Children.

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.