Objective: This review summarizes the morphology, structural features, epidemiology, pathogenesis, clinical manifestations, and laboratory diagnosis of Leptospira spp.

Methods: A narrative literature review was conducted using international scientific databases, including PubMed, Scopus, Web of Science, and ScienceDirect, as well as guidelines and reports from the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC). Relevant review articles, clinical studies, and diagnostic guidelines were selected based on scientific relevance and methodological quality. [1-4]

Results: Leptospira spp. are thin, motile spirochetes that survive well in moist environments. Their spiral morphology and periplasmic flagella contribute to tissue invasion and environmental persistence. Leptospirosis is a globally distributed zoonotic infection maintained in nature by animal reservoirs, especially rodents and livestock, and transmitted to humans mainly through contact with contaminated water, soil, or animal fluids. The clinical spectrum ranges from mild self-limited febrile illness to severe multisystem disease involving the liver, kidneys, lungs, and central nervous system. Laboratory diagnosis is highly stage-dependent. Polymerase chain reaction (PCR) is most useful during the early septicemic phase, whereas serological methods, especially the microscopic agglutination test (MAT) and IgM-based assays, are more informative in the later phase. Culture and direct microscopy have limited routine diagnostic value because of slow growth and low sensitivity. [5-11]

Conclusion: Accurate diagnosis of leptospirosis requires an integrated approach combining clinical suspicion, epidemiological history, and stage-appropriate laboratory testing. Early recognition and timely treatment are essential to reduce complications and improve clinical outcomes. [1,5,9-11]

Leptospira; leptospirosis; spirochetes; zoonotic infection; pathogenesis; epidemiology; laboratory diagnosis; PCR; serology

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Rodríguez-Rodriguez VC, Castro AM, Soto-Florez R, Urango-Gallego L, Calderón-Rangel A, Agudelo-Flórez P, Monroy FP. Evaluation of Serological Tests for Different Disease Stages of Leptospirosis Infection in Humans. Trop Med Infect Dis. 2024;9(11):283. doi:10.3390/tropicalmed9110283.