Clinical and laboratory associations of severity in a Sri Lankan cohort of patients with serologically confirmed leptospirosis: a prospective study

Abstract

Background: Leptospirosis results in significant morbidity and mortality. This study elucidates markers of severity in a cohort of Sri Lankan patients.

Methods: Patients presenting to three healthcare institutions in the Western province of Sri Lanka with leptospirosis serological confirmed by the microscopic agglutination test (MAT) were included. Prospective data regarding demographic, clinical and laboratory parameters was extracted. Univariate associations and subsequent multivariate logistic regression models were constructed.

Results: The study included 232 patients, with 68.5% (159) demonstrating severe disease. Significant associations of severe disease at a significance level of p<0.05 were fever >38.8°C on presentation, age >40 years, muscle tenderness, tachycardia on admission, highest white cell count >12 350/mm(3) and <7900/mm(3), highest neutrophil percentage >84%, haemoglobin >11.2 g/dL and <10.2 g/dL, packed cell volume (PCV) >33.8% and <29.8%, lowest platelet count <63 500/mm(3), highest alanine transaminase (ALT) >70 IU/L and hyponatremia with sodium <131 mEq/L. On multivariate analysis, PCV <29.8% (p=0.011; OR 3.750; CI: 1.394-10.423), ALT >70 IU/L (p=0.044; OR 2.639; CI: 1.028-6.774) and hyponatremia <131 mEq/L (p=0.019; OR 6.413; CI: 1.353-30.388) were independent associations of severe disease.

Conclusions: Severity associations were demonstrated with both clinical and laboratory parameters. There is a need for novel biomarkers for prediction of severity in leptospirosis.

Keywords: Leptospirosis; Severity; Sri Lanka.