Identification of Dominant Leptospira Serogroups among Leptospirosis Cases and Their Clinical Outcomes: A Prospective Hospital-Based Study in Mangaluru, India

Abstract

ABSTRACT. Leptospirosis is a reemerging zoonotic disease of worldwide significance, endemic to the southern region of India, with clinical manifestations similar to other febrile illnesses; hence, it is often misdiagnosed and underreported. Inadequate information about the disease burden and the regional circulating serogroups contributes to its neglected disease status. This study aimed to identify the infecting Leptospira serogroup in the coastal region of Mangaluru and study the clinical symptoms and outcome among leptospirosis patients. Serum samples were collected from 30 patients with confirmed leptospirosis admitted to a tertiary care center in Mangaluru and screened by microscopic agglutination test (MAT) for the infecting serogroup. The clinical profile of these cases was reviewed, and data regarding epidemiological factors such as age, sex, complications, and mortality were recorded. The MAT identified a higher occurrence of serogroup Bataviae (n = 7, 43.75%) and serogroup Australis (n = 5, 31.25%) compared with other serogroups screened in this study population. Patients were aged 16 to 65 years, with a predominance of males. The clinical presentation of leptospirosis ranged from a mild febrile illness to multiorgan failure. Fever (n = 29, 96%) was the common clinical presentation, followed by myalgia, nausea, and abdominal pain. Acute kidney injury, acute respiratory distress syndrome, and multiple organ dysfunction syndrome were the common complications observed. Determining the circulating serogroup is necessary to understand the epidemiology and diversity of Leptospira serogroups among animals and humans to strategize appropriate preventive measures.