Leptospirosis: Epidemiologic Factors, Pathophysiological and Immunopathogenic

Leptospirosis is a disease of worldwide distribution present on all continents except Antarctica (Adler & Montezuma, 2010) affecting wildlife, domestic and man. Leading consequently serious socio-economic and public health. It is currently the highest incidence of zoonosis in the world, also considers as an occupational disease, and reemerging infectious disease, occurring endemic and epidemic in developing countries with tropical and subtropical (Levett, 2001; Bharti et al., 2003, Ko et al , 2009). more frequently in tropical and developing countries (Bharti et al, 2003), acarrretando with this serious social and economic problems. The disease is an acute infection caused by a spirochete Leptospiraceae family, consisting of two genera, Leptospira and Leptonema. Recently, the genus Leptospira was divided into 17 species based on molecular classification (DNA), saprophytic and pathogenic species (Brazil 2002; Bharti et al. 2003). The pathogenic species are: L. interrogans, L. alexanderi, L. fanei, L. inadai, L. kirschineri, L. meyeri, L. borgetersenii, L. weil, L. noguchi, L. santarosai, Genomospecie 1, Genomospecie 4, 5 Genomospecie. The serotypes of Leptospira are interrogans Australis, Bratislava, Bataviae, Canicola, Hebdomadis, Icterohaemorrhagiae Copenhageni, Lai, Pomonoa, Pyrogenes, Hardjo and divided into serogroups (Ribeiro, 2006). The reservoir animals, mainly rats, are the most frequent disseminators, by eliminating spirochetes in the urine. Leptospira spp. can enter the body through intact skin or not, the oral mucosa, nasal and conjunctival (Kobayashi, 2001). The clinical manifestations of leptospirosis vary according to species, individual susceptibility, the pathogenicity and virulence of the serovar involved (Venugopal, 1990, Macedo 1991). After penetration of the bacteria likely, the organism spreads to the bloodstream to all organs (Hüttner et al, 2002). The incubation period is usually around 5-14 days, but have been described as short or long periods in some cases, such as 72 hours a month or more (Jezior, 2005). Leptospirosis is characterized by a vasculitis. The damage to capillary endothelial cells to the underlying cause of clinical manifestations such as renal tubular dysfunction, liver disease, myocarditis and pulmonary hemorrhage (Hill, 1997). The clinical features are: a) kidneys: interstitial nephritis, tubular necrosis, decreased capillary permeability, and the combination of hypovolemia resulting in renal failure, b) in the liver: necrosis with central lobular proliferation of Kupffer cells and hepatocellular dysfunction c) in the lung, the lesions were secondary to vascular damage resulting in interstitial hemorrhage d) in the skin, the lesions occur as a result of vascular epithelial