Demographic and clinical features of leptospirosis: three-year experience in central Taiwan

Leptospirosis is a major cause of fever in subtropical and tropical areas. The clinical manifestations are protean, ranging from very mild and nonspecific symptoms to severe septic shock and death. This retrospective study investigated the demographic and clinical features of leptospirosis in central Taiwan over 3 years, with emphasis on pulmonary manifestations.

We analyzed the clinical characteristics of serologically-confirmed leptospirosis cases at a tertiary teaching hospital from October 2002 to October 2005.

Twenty three confirmed cases were included and Leptospira santarosai serovar Shermani was the most commonly identified serovar (77.3%). The male-to-female ratio was 2.67:1 and the average age was 42.4 years. Nineteen cases (82.6%) were hospitalized, 3 were diagnosed in the outpatient setting and 1 died before admission. The majority of cases (63.6%) occurred in rainy months (from June to October). Fever (incidence, 100%), anorexia (74%), headache (61%), gastrointestinal upset (53%), myalgia (48%), and cough (48%) were the common clinical manifestations. Fifteen cases (63%) had respiratory symptoms and twelve (52%) had chest roentgenography abnormalities. Multiple nodular densities pattern (42%) was the most common abnormal finding on chest plain film. Three patients met the criteria of Weil's syndrome. The overall mortality rate was 4.3%.

Respiratory symptoms or abnormal findings on chest X-ray were not uncommon in patients with leptospirosis. In addition to hepatic or renal dysfunction, leptospirosis should be seriously considered in patients with pulmonary symptoms and fever, especially in subtropical and tropical areas.