DERMATOLOGICAL MANIFESTATIONS OF LEPROSY: CLINICAL, DIAGNOSTIC, AND THERAPEUTIC ASPECTS

Abstract

Leprosy is a chronic infectious disease caused by Mycobacterium leprae, with a predilection for the skin and peripheral nerves, representing a significant public health problem in endemic countries such as Brazil. Dermatological manifestations constitute the main clinical axis of the disease and often represent the first detectable sign, being fundamental for early diagnosis and prevention of permanent disabilities. The cutaneous expression of leprosy reflects the interaction between the bacillus and the host's cellular immune response, determining a clinical spectrum that varies according to the immunological profile. In paucibacillary forms, there is a predominance of an effective cellular immune response, resulting in well-defined lesions, usually single or in small numbers, with early hypoesthesia and loss of skin appendages. In multibacillary forms, associated with cellular immunity deficiency, diffuse cutaneous infiltration, multiple symmetrical lesions, nodules, and thickening of the skin are observed, and madarosis and characteristic facial alterations may occur. Elementary lesions include hypopigmented or erythematous macules, infiltrated plaques, papules, nodules, and diffuse infiltration. Altered thermal, pain, or tactile sensitivity is a central semiological finding and should be systematically investigated. Reactional states, such as type 1 (reversal) and type 2 (erythema nodosum leprosum) reactions, can worsen the cutaneous and neural condition, increasing the risk of sequelae. Diagnosis is essentially clinical, based on the presence of cutaneous lesions with sensory alteration, peripheral neural thickening, and/or identification of acid-fast bacilli in specific tests. Bacilloscopy and skin biopsy aid in classification and diagnostic confirmation. Treatment is based on multidrug therapy standardized by the World Health Organization, with rifampicin, dapsone, and clofazimine, promoting lesion regression and interruption of transmissibility. Appropriate management of reactional states is essential to prevent irreversible neural damage. Thus, early recognition of dermatological manifestations remains a central strategy for reducing morbidity associated with leprosy.