Leprosy is a chronic infectious disease caused by Mycobacterium leprae and is transmitted through direct contact. It primarily affects the skin, mucous membranes, and peripheral nerves, but deeper tissues and organs may also be involved. The disease is predominantly found in tropical and subtropical regions of Asia, Africa, and Latin America, with men being affected more frequently than women. Leprosy is neither hereditary nor vertically transmitted from mother to child.
Clinical Manifestations
In addition to systemic symptoms, leprosy can present with specific manifestations in the ear, nose, and throat:
Nasal Leprosy
This is the most common form of ENT involvement in leprosy and is one of the earliest sites affected by the disease, predominantly in the lepromatous type. In the early stages, the disease invades hair follicles, leading to the loss of nasal hair in the nasal vestibule, ulceration, and nodular infiltration in the mucosa. This can result in persistent ulcers or cicatricial adhesions. In the late stages, mucosal gland atrophy, nasal dryness, and crust formation occur, resembling changes seen in atrophic rhinitis. Severe cases may involve perforation of the cartilaginous part of the nasal septum, destruction of the columella, and collapse of the nasal tip close to the upper lip, which may mimic saddle nose caused by atrophic rhinitis or syphilis. Nasal secretions often contain large amounts of Mycobacterium leprae, making the disease highly contagious.
Pharyngeal Leprosy
This form is less common and is usually a downward extension of lepromatous nasal leprosy. Early stages may feature acute edema of the pharyngeal mucosa, while later stages are characterized by dryness, crusting, nodular infiltration, and ulceration. Necrosis in affected tissues can lead to symptoms such as hypernasal speech and food regurgitation.
Laryngeal Leprosy
This typically occurs as a secondary extension from nasal or pharyngeal leprosy. Nodular infiltration and ulceration in the larynx are common, eventually leading to scarring. Examination may reveal erythematous or pale epiglottis, thickening, curling, deformity, or even tissue loss. Symptoms such as hoarseness, stridor, and mild respiratory difficulty may be present.
Aural Leprosy
Aural involvement is localized to the skin as part of systemic leprosy. It most commonly affects the pinna, especially the earlobe, with the external auditory canal rarely involved. Early forms present as skin nodules, which may develop into lepromas. The earlobe can become 2–3 times larger than normal. Lepromatous aural leprosy typically manifests with infiltration, nodule formation, ulceration, scarring, skin wrinkling, and tissue loss. Enlargement and tenderness of the great auricular nerve are significant diagnostic features of aural leprosy. Facial nerve involvement can lead to muscle spasms and/or facial paralysis.
Diagnosis
A preliminary diagnosis is established based on a history of contact with leprosy patients and typical lesions affecting the skin, mucous membranes, and peripheral nerves. Definitive diagnosis requires identifying Mycobacterium leprae in secretions or biopsy samples from affected tissues. Leprous lesions in the upper respiratory tract should be differentiated from diseases such as tuberculosis and syphilis.
Treatment
The primary treatment involves systemic anti-leprosy therapy, complemented by symptomatic management of ear, nose, and throat lesions.