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

LOCALIZED MYOSITIS AND TRANSIENT ENCEPHALOPATHY AS PRESENTING SYMPTOMS IN MURINE TYPHUS

Murine typhus in the pediatric population has increased substantially in recent years. The most common clinical presentation of murine typhus includes fever, rash, headaches and myalgias. Murine typhus presenting with predominant myositis and/or encephalopathy is rare. It is important to recognize unusual clinical manifestations of murine typhus in children for early diagnosis and treatment.

Flea-Borne Typhus as a COVID-19 Mimic: A Report of Four Cases

Flea-borne typhus (FBT), due to Rickettsia typhi and R. felis, is an infection causing fever, headache, rash, hepatitis, thrombocytopenia, and diverse organ manifestations. Cough occurs in about 30% of patients with FBT, and chest X-ray abnormalities are seen in 17%. Severe pulmonary manifestations have also been reported in FBT, including adult respiratory distress syndrome and pulmonary embolism. Because of these pulmonary manifestations, FBT can mimic Coronavirus Illness 2019 (COVID-19), a febrile illness with prominent respiratory involvement. Flea-borne typhus and COVID-19 may also have similar laboratory abnormalities, including elevated ferritin, C-reactive protein, and D-dimer. However, elevated transaminase levels, rash, and thrombocytopenia are more common in FBT. Herein, we present four cases of patients with FBT who were initially suspected to have COVID-19. These cases illustrate the problem of availability bias, in which the clinician thinks a particular common condition (COVID-19 in this case) is more prevalent than it actually is.

Comparison of Multisystem Inflammatory Syndrome (MIS-C) and Dengue in Hospitalized Children

OBJECTIVE

Multisystem inflammatory syndrome (MIS-C) in children is a febrile illness that has overlapping presentation with other locally prevalent illnesses. Clinicolaboratory profile of children admitted with MIS-C and dengue were compared to understand their presentation at the outset.

METHODS

This was a retrospective study of children ≤ 12 y admitted with MIS-C (WHO definition) or laboratory-confirmed dengue between August 2020 and January 2021 at a tertiary center in North India.

RESULTS

A total of 84 children (MIS-C - 40; dengue - 44) were included. The mean (SD) age [83.5 (39) vs. 91.6 (35) mo] was comparable. Rash (72.5% vs. 22.7%), conjunctival injection (60% vs. 2.3%), oral mucocutaneous changes (27.5% vs. 0) and gallop rhythm (15% vs. 0) were seen more frequently with MIS-C, while petechiae [29.5% vs. 7.5%], myalgia (38.6% vs. 10%), headache (22.7% vs. 2.5%), and hepatomegaly (68.2% vs. 27.5%) were more common with dengue. Children with MIS-C had significantly higher C-reactive protein (124 vs. 3.2 mg/L) and interleukin 6 (95.3 vs. 20.7 ng/mL), while those with dengue had higher hemoglobin (12 vs. 10.2 g/dL) lower mean platelet count (26 vs. 140 × 10⁹/L), and greater elevation in aspartate (607 vs. 44 IU/L) and alanine (235.5 vs. 56 IU/L) aminotransferases. The hospital stay was longer with MIS-C; however, PICU stay and mortality were comparable.

CONCLUSION

In hospitalized children with acute febrile illness, the presence of mucocutaneous features and highly elevated CRP could distinguish MIS-C from dengue. The presence of petechiae, hepatomegaly, and hemoconcentration may favor a diagnosis of dengue.