Manifestations and outcomes of leptospirosis during local outbreaks in high endemic districts of Sri Lanka: A retrospective multi-center study

Objective:To determine the clinical presentations and disease outcomes of suspected and confirmed cases of leptospirosis from 3 high endemic districts of Sri Lanka,during outbreaks reported between 2013 and 2017.Methods:The retrospective multi-center study was carried out during 2013-2017 in 5 selected hospitals representing 3 high endemic districts in Sri Lanka.Clinically suspected leptospirosis patients were recruited according to the Communicable Disease Epidemiology Profile Sri Lanka,WHO.Leptospirosis was confirmed by either single microscopic agglutination test titre 1:400 or by positive polymerase chain reaction(PCR)test result.Results:Out of 372 clinically suspected cases,29.00%were confirmed as leptospirosis cases by either microscopic agglutination test(50.00%)or positive polymerase chain reaction(52.77%)and 12.90%were presumptively identified as leptospirosis.Clinical symptoms(headache,vomiting,jaundice and dyspnoea)and variations in haematological parameters(haemoglobin,platelet count)and biochemical parameters(serum creatinine,serum urea,serum bilirubin and C-reactive protein)were associated with confirmed leptospirosis(P<0.05).Acute kidney injury,meningitis,myocarditis,pulmonary haemorrhage and acute liver failure was seen among 21.30%,12.04%,6.48%,6.48%,5.56%,respectively with 4.63%fatality among the leptospirosis confirmed patients.The sensitivity,specificity,positive predictive value and negative predictive value of the case definition of Ministry of Health,Sri Lanka were 96.29%,9.09%,31.13%and 85.71%,respectively,when benchmarked against either positive polymerase chain reaction or microscopic agglutination test as the gold standard.Conclusions:Acute kidney injury is the predominant complication observed among the leptospirosis confirmed patients.However,pulmonary haemorrhage is predominantly associated with mortality.The case definition of Ministry of Health,Sri Lanka is found to have higher sensitivity and enabled the screening of all probable cases of leptospirosis.