摘要：Leprosy is a chronic bacterial infection caused by Mycobacterium Leprae, an acid-fast bacillus forced to live in the intracellular space mainly in Schwann cells and macrophages, which affects the skin, nerves and eyes. The existence of the disease knows since antiquity, but still remains a serious public health problem worldwide especially in endemic areas. Its clinical spectrum is given by the response generated for the immune system against the bacillus. Today we know different forms of disease presentation, including the determined poles as the tuberculoid and lepromatous, the indeterminate and borderline leprosy. Early diagnosis is the main tool to achieve appropriate treatment, prevent disabilities and rehabilitate the sick patient. The treatment set by the WHO since 1984 consists in a multidrug therapy based on the classification paucibacillary or multibacillary, according to the number of skin lesions and the number of bacilli presents in biopsy. We report the case of a female patient, 51 years old, diagnosed with Borderline Lepromatous Leprosy, who presented a leprosy reaction, type I and drug allergy. We discuss the diagnostic and the treatment employed. Keywords: Leprosy, borderline lepromatous leprosy, leprosy reaction, drug allergy, treatment.
