Clinical Profile of Leptospirosis in North Chennai: A Study of 106 Cases

INTRODUCTION: Infectious disease is an important cause of morbidity and mortality in our country. Leptospirosis has been considered a rare zoonotic disease in India, with only sporadic cases recorded. Recently, however the disease was reported in Chennai during monsoon months in mini-epidemic proportions. In Chennai leptospirosis occurs in severe form causing jaundice and renal failure. It is usually reported during monsoon months. Recently diagnosis of leptospirosis has been simplified using modified Faine’s criteria. This criteria utilizes clinical, epidemiological and laboratory parameters for diagnosis. This criterion has been useful for diagnosis of milder forms of leptospirosis. This study has been undertaken to study the clinical features, epidemiological profile of leptospirosis in our hospital which caters to population in north Chennai. Leptospirosis has been frequently under diagnosed and under reported due to lack of awareness of disease and lack of appropriate diagnostic facilities. Combining clinical expertise & awareness with laboratory backup, increases the recognition of the disease. AIM OF THE STUDY: 1. To study the clinical features of mild & severe leptospirosis utilizing modified Faine’s criteria in North Chennai. 2. To evaluate the epidemiological risk factors in these patients. MATERIALS AND METHODS: Patients admitted to the medical wards of Govt.Stanley hospital with fever due to infectious disease of duration of more than 5 days who were positive by slide agglutination test were taken up for the study. Patients aged 15 -60 years were taken up for the study. The period of study was from May 2004 to December 2005. Diagnostic criteria: Leptospirosis was diagnosed utilizing Modified Faine’s criteria - Clinical, Epidemiological, Lab data (score >25). Exclusion criteria: Malaria, viral hepatitis, UTI, enteric fever, TB and pediatric cases were excluded from the study. RESULTS: A total of 106 patients diagnosed of leptospirosis were analyzed. There were 69 males & 37 females. The mean age was 31.2 years. The age/sex group data shows that maximum number of cases were seen in age group 21 to 30 years. The occupation of the patients in which maximum percentage of cases seen outdoor manual work of about 39.4% and in North Chennai areas surrounding the hospital has the maximum number of cases. contaminated environment & animal contact was about 95% & 94% respectively. Rainfall was seen in 50% of cases. Table -24 shows the seasonal distribution of cases. Cases occurred throughout the year with maximum number of cases during September to December. clinical features in which fever 100%, headache-95%, and myalgia- 90% with conjunctival suffusion about 18%. Hypotension and hypovolemia constituted about 26%. Anicteric presentation was about 82%. Table-26 shows the faine scoring 48 % of the cases had a score between 25-30 and another 45 % had score between 31- 35. renal function data, about 10.3% had renal failure (mean creatinine 3.5 mg%) and table 29 shows liver function data, about 17.8% had jaundice (mean Bilirubin 2.8 mg%). Table-30 shows the Hemogram details with total count, platelet and hemoglobin almost within normal range. All mild cases were treated with oral Doxycyline. Severely ill patients (organ dysfunction) treated with IV penicillin. 2 patients dialyzed. All patients recovered (mortality nil). SUMMARY: 1) A total of 106 patients with leptospirosis was analyzed, males-69, females - 37 & mean age was 31.2. 2) Out door manual workers were the group at highest risk to develop Leptospirosis. 3) Contaminated environment (95%), animal contact (94%) were important epidemiological factors. Rainfall was important risk factor in 50% of patients. 4) Most of the cases occurred between August to December. 5) Anicteric leptospirosis (82%) along with fever, headache, and myalgia were common clinical presentation. Conjunctival suffusion & Meningism was rare. 6) Jaundice occurred in 17.8% (Mean Bilirubin 2.8 mg %). 7) Renal failure occurred in 10.3% (mild 5.6%, moderate 1.8%, severe 2.8%), 2 patients were dialyzed. 8) All patients recovered , mortality- nil. 9) Modified Faine’s criteria was valuable for diagnosis of leptospirosis (especially anicteric). CONCLUSION: 1. Anicteric leptospirosis is the common presentation (82%) in north Chennai. 2. Lower incidence of jaundice and renal failure. 3. It also occurs in non-monsoon months. 4. Contaminated environment is an important risk factor/ outdoor manual workers are the vulnerable risk group. 5. Role of modified Faine’s criteria with single diagnostic test MSAT makes diagnosis easy. 6. Recommended that all fever patients be evaluated for leptospirosis.