Title : Risk factors of mortality and development of a scoring system for predicting mortality among patients with leptospirosis
Abstract:
Background
Leptospirosis, a potentially fatal zoonotic infection, has been on the rise in Kerala, India particularly among individuals involved in water-related occupations and activities. With increasing incidence and mortality rates, there is an urgent need to identify key risk factors for mortality and develop effective intervention strategies. Currently, the only existing scoring system to predict mortality in leptospirosis is the Quick Lepto Score, which was based on retrospective study data and lacks external validation. This study aims to identify the risk factors and propose a mortality predictive scoring system to guide early management and improve patient outcomes.
Objective
The primary objective was to study the risk factors associated with mortality among leptospirosis patients admitted to Kozhikode Medical College, Kerala, India. The secondary objective was to develop and validate a scoring system for predicting mortality in leptospirosis patients.
Methodology
A cross-sectional study with a prospective component was conducted among leptospirosis patients admitted to the Department of General Medicine, Government Medical College, Kozhikode. Over one year and six months, 250 patients aged 13 and above were enrolled based on specific inclusion criteria. Detailed clinical evaluations and data collection were performed using a structured pro forma. Parameters were compared between survivors and non-survivors, and associations with mortality were analyzed. A scoring system was subsequently developed and validated to predict mortality and guide early management.
Results
Out of the 250 cases, 15.5% succumbed to the illness, resulting in a case fatality rate of 15.5%. Several independent risk factors associated with mortality were identified: age over 50 years, presence of jaundice, dyspnoea, hypotension (BP < 90/60 mm Hg), pulse rate of 100 bpm or higher, serum albumin level below 3.5 mg/dL, creatinine level above 3.2 mg/dL, and platelet count below 40000/µL. These predictors were used to develop a scoring system for assessing mortality risk. The total score was 12, with scores above 7 indicating a 35 times increased risk of mortality. Validation of the scoring system in 25 new patients demonstrated an NPV of 100%, a PPV of 88.9%, a sensitivity of 72.7%, and a specificity of 64%.
Conclusion
The developed scoring system enables clinicians to quickly identify patients at risk of mortality, facilitating early intervention. This tool is cost-effective, easy to use at the bedside, and requires minimal training, making it particularly valuable in resource-limited settings where leptospirosis is more prevalent. By using our scoring system, clinicians can effectively triage leptospirosis patients, ensuring those in need of intensive care are transferred to higher-level healthcare facilities.
Keywords
Leptospirosis, Zoonotic infection, Mortality, Risk factors, Scoring system, Quick Lepto score
