The Value of Metagenomic Next-Generation Sequencing in Leishmaniasis Diagnosis: A Case Series and Literature Review

BACKGROUND: Leishmaniasis is a zoonotic disease caused by Leishmania spp. and spreads through sandfly bites. Owing to the wide range of nonspecific clinical symptoms, patients with leishmaniasis are frequently misdiagnosed or underdiagnosed. METHODS: The study participants were 7 metagenomic next-generation sequencing (mNGS)–diagnosed patients with leishmaniasis who could not be diagnosed using conventional methods. Clinical data were retrospectively collected and analyzed. When searching PubMed for mNGS and leishmaniasis, 8 peer-reviewed case reports in English were retrieved. RESULTS: A total of 7 patients with recurrent fever, pancytopenia, and significant splenomegaly were included in this study. Only 3 individuals tested positive for rK39. Two individuals, 1 of whom was HIV-positive, had Leishmania amastigotes identified in their bone marrow. However, all patients’ blood mNGS findings pointed to Leishmania infection, and they were finally diagnosed with leishmaniasis. Sodium stibogluconate therapy with a short course of amphotericin B was administered to all patients. The prognosis for the remaining patients was good, except for 1 who died of multiple organ failure. CONCLUSIONS: mNGS could be used to identify leishmaniasis, particularly in patients who are difficult to diagnose using conventional approaches.