Background Leptospirosis, a tropical, spirochaetal infection presents as an acute febrile illness with organ injury. There is a paucity of data on clinical characteristics and treatment for Leptospirosis Pulmonary Haemorrhage Syndrome (LPHS).   Methodology and principal findings A retrospective cohort study was conducted including all patients with LPHS treated in the medical Intensive Care Unit (ICU), National Hospital Sri Lanka from 2019 to 2022 to describe the clinical characteristics and factors related to poor outcomes. Survival of patients who received different treatment modalities for LPHS was compared. Seventy patients were studied with a mean age of 42.69 ± 27.84 years and 61 (87.1%) males. Forty-nine (70%) were mechanically ventilated and 16 (22.9%) died. Higher heart rate, higher lactate, lower pH on admission to ICU, and requirement of blood product transfusion were associated with increased mortality.  Patients were treated with plasmapheresis (PLEX), intranasal desmopressin (DDAVP), and intravenous steroids alone or in combination as the specific treatment for LPHS.  Seven (10%) patients were treated with PLEX alone, 13 (18.6%) with PLEX + DDAVP, 46 (65.7%) with PLEX + DDAVP + steroids, and 4(5.7%) were treated with steroids alone. All patients who received PLEX and DDAVP combination survived. There were 11 (23.9%) deaths in the PLEX+ DDAVP + steroids group, 3 (49.2%) in the PLEX alone group, and 2 (50%) in the steroids alone group. Mortality was least when PLEX was done for 3 days. Twenty-five (35.7%) patients developed hospital-acquired infections and risk factors were mechanical ventilation and longer ICU stay.    Conclusions Presence of tachycardia, acidosis, and high lactate predicted death in LPHS. PLEX and DDAVP combination had better survival than other treatments alone or in combination for LPHS. Randomized clinical trials are urgently needed to identify the role of PLEX and DDAVP in treating LPHS.

The authors have declared no competing interest.

The author(s) received no specific funding for this work.

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Ethics review committee, Faculty of medicine, University of Colombo

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Data are available in the BioStudies database (https://www.ebi.ac.uk/biostudies/) under accession number S-BSST1368.

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