Leprosy (Hansen Disease)

Leprosy, or Hansen disease, had recently been diagnosed in a 39-year-old man. He presented to the tropical disease unit of Harare Hospital, Zimbabwe, for follow-up (A). The patient had lost all fingers and toes; a lower extremity stump ulcer with some drainage had developed, and the distal extremities had become less sensitive to touch (B). He also complained of facial numbness but denied fever, chills, nausea, vomiting, and weight loss. He was taking no medications. The very frail patient had a collapsed nose and had lost his eyebrows and eyelashes. Small ulcerations and pus drainage were noted on the right lower extremity stump site. Diffuse distal sensory deficits were detected as well. A presumptive diagnosis of multibacillary leprosy was made. For 12 months, the patient was given rifampin, 600 mg, and clofazimine, 300 mg, monthly; and dapsone, 100 mg, and clofazimine, 50 mg, daily. Some patients with multibacillary leprosy receive this regimen for up to 24 months. No bony erosions were seen on the roentgenogram of the leg. The ulcers were treated with penicillin and daily wet-to-dry dressing changes; there were no further sequelae. Dr XinQi Dong of New Haven, Conn, writes that leprosy is caused by the acid-fast bacillus Mycobacterium leprae, which is transmitted most likely via respiratory droplets that are disseminated especially during sneezing. The disease is endemic in tropical and subtropical Asia, Africa, Central and South America, Pacific regions, and the southern United States. It is estimated that between 10 and 20 million people worldwide have leprosy.¹ Skin lesions may occur insidiously as pale, anesthetic macules; discrete, erythematous, infiltrated nodules; or a diffuse skin infiltration. The lesions may involve the skin, superficial nerves, nose, pharynx, larynx, testicles, and eyes. Another patient with leprosy (C) has ocular manifestations of the disease. Lagophthalmos, the inability of the eyelid to close completely, can lead to exposure keratitis or corneal ulceration and cause blindness. Nerve infiltration and thickening can lead to neurologic disturbances, such as anesthesia, neuritis, and paresthesia. Bilateral ulnar neuropathy is very common.² If untreated, skin infiltration and nerve involvement may become extreme, leading to trophic ulcers, bone resorption, and loss of digits. M leprae does not grow in artificial media. Hematologic and serum chemistry findings are not elucidating; skin biopsy specimens that demonstrate acid-fast bacilli confirm the diagnosis. Combination therapy is recommended for all types of leprosy.³ Patients with paucibacillary disease receive rifampin, 600 mg monthly, and dapsone, 100 mg daily, for 6 months. Those with multibacillary leprosy receive the regimen outlined previously for the first patient.