Leptospirosis-induced diffuse alveolar hemorrhage: A rare case report from a non-epidemic area and literature review

This case underscores that leptospirosis can present as fulminant DAH even in non-endemic regions. A high index of suspicion, aided by epidemiological clues and the rapid application of metagenomic next-generation sequencing/reverse transcription quantitative PCR, is crucial for timely diagnosis. Prompt targeted antimicrobial therapy combined with intensive organ support is essential for a favorable outcome in severe cases.