Clinical Profile and Severity Correlation of Acute Leptospirosis in Northern India, 2019-2023: A Tertiary Care Center-based study

BACKGROUND: Leptospirosis is a globally important zoonotic disease with substantial morbidity and mortality, yet it remains underreported in Northern India. This study aimed to evaluate the seroprevalence, clinical characteristics, and severity determinants of acute leptospirosis in a tertiary care setting. METHODS: We conducted a retrospective cross-sectional analysis of 174 hospitalized leptospirosis patients from 20,162 admissions between 2019 and 2023. The diagnosis was established using Leptospira IgM ELISA testing. Clinical, haematological, and imaging parameters were systematically evaluated. RESULTS: The incidence of leptospirosis was 0.9%, peaking at 38.5% post-monsoon. Rural residents (64.9%), males (59.2%), and individuals involved in agricultural work (62.6%) were predominantly affected. Common presentations were fever (100%), headache (70.7%), myalgia (62%), and calf pain (50%), followed by jaundice (39.7%), and reduced urine output (33.3%).. The mortality rate was 20.1%. Severity correlated significantly with nausea/vomiting, abdominal pain, cough, and complications, including diffuse alveolar haemorrhage (DAH), disseminated intravascular coagulation (DIC), multiorgan dysfunction syndrome (MODS), hepatic dysfunction, acute renal injury, and leukocytosis. DISCUSSION: The findings emphasize the critical need for early risk stratification and timely intervention to improve clinical outcomes. Identifying clinical and laboratory predictors of severity can significantly guide early management strategies in endemic areas. CONCLUSION: Several clinical and laboratory parameters are significant predictors of leptospirosis severity. Early recognition and risk stratification based on these indicators are crucial to improving patient outcomes. Enhanced surveillance, preventive measures, and clinician awareness are urgently needed to address this neglected tropical disease.