# Rare disease mimicking multisystem inflammatory syndrome in children

## TL;DR

A teenager with symptoms resembling a rare inflammation syndrome caused by a virus was actually diagnosed with a parasitic infection, highlighting the need to consider infectious diseases in similar cases.

## Contribution

This case report highlights the diagnostic challenge between MIS-C and endemic infections like leishmaniasis.

## Key findings

- A 16-year-old patient initially suspected of MIS-C was diagnosed with visceral leishmaniasis.
- The case shows diagnostic overlap between MIS-C and leishmaniasis, emphasizing the need for infectious workup in endemic regions.

## Abstract

Multisystem inflammatory syndrome (MIS-C) is a rare but serious condition associated with SARS-CoV-2, the virus that causes COVID-19. We report a 16-year-old female who presented with seven days of fever, abdominal pain, headache, and fatigue. Physical examination revealed meningeal irritation. Laboratory findings showed pancytopenia, elevated inflammatory markers, and positive SARS-CoV-2 IgG with negative PCR. The patient had no history of COVID-19 vaccination or previous confirmed infection. Initially evaluated as MIS-C due to fever, multisystem involvement, and antibody positivity, she was subsequently diagnosed with visceral leishmaniasis after bone marrow aspiration revealed Leishmania amastigotes. This case highlights the diagnostic overlap between MIS-C and endemic infections such as leishmaniasis and underlines the importance of considering infectious etiologies in hyperinflammatory presentations, especially in endemic areas.

The online version contains supplementary material available at 10.1186/s12887-025-06451-5.