[Leptospirosis].

Leptospirosis is the most common zoonosis worldwide, although most cases occur in tropical countries. Leptospira interrogans, a spirochete, is the causative agent. Rats are the main reservoir. Most patients present a mild clinical form of the disease, which consists of a self-limited febrile process, without jaundice. Nevertheless, about 10% of patients suffer severe infections, with intense jaundice. Typically the disease manifests in two phases: acute or leptospiremic and immune or leptospiuric, although in many patients the two phases are indistinguishable, and in mild cases the second one is frequently absent. Diagnosis is carried out by serology or culture of the microorganism. Treatment consists of antibiotics such as penicillin G, ceftriaxone, doxycycline or amoxicillin.