HANSEN’S DISEASE

Epidemiology 1.25 cases per 10,000 persons India accounts for 80% of cases Brazil, Indonesia, Myanmar, Madagascar and Nepal endemic in the coastal southeastern US and in Hawaii –related to exposure to armadillos

The Infectious Agent Mycobacterium leprae –a weak acid-fast organism –It grows best at temperatures (30°) below the core body temperature of humans localization of leprosy lesions to cooler areas of the body and the sparing of the midline and scalp –favors intracellular locations –long generation time of days

Diagnosis must be considered in any patient with neurologic and cutaneous lesions Smears –cooler areas of the skin, such as the earlobes, elbows and knees, and stained with acid-fast stains Skin biopsies from skin or nerve lesions using Fite-Faraco stain Seropositivity

Classification WHO classification 1.Paucibacillary – patients with few organisms in their tissue 2.Multibacillary - patients with large number of organisms in their tissue

Classification Ridley and Jopling classification –based on clinical, bacteriologic, immunologic and histopathologic features 1.Tuberculoid leprosy 2.Borderline tuberculoid leprosy 3.Borderline leprosy 4.Borderline lepromatous leprosy 5.Lepromatous leprosy 6.Histoid leprosy

Tuberculoid leprosy Paucibacillary –solitary or few in numbers (usually <5) and asymmetrical in distribution –erythematous or hypopigmented plaque with elevated border that slopes down to a flattened atrophic center (a saucer right side up) –lesions are anesthetic or hypersthetic and anhydrotic –face, limb and trunks.

Hypopigmented Macule

Borderline tuberculoid leprosy Multibacillary – Smaller and more numerous than tuberculoid leprosy – Satellite lesion around large macules or plaques – Bacilli are more abundant and grenz zone is present

Borderline leprosy Multibacillary –Numerous but countable –Red, irregularly shaped plaques –Small satellite lesions may surround larger plaques –Lesions are generalized but assymetrical. –The edges are not so well define

Borderline lepromatous leprosy Multibacillary – lesions are symmetrical and numerous (too many to count) – stocking-glove pattern of nerve involvement

Lepromatous leprosy Multibacillary –Pale lepromatous macules or infiltrations –Numerous bacilli –Lesions are diffusely and symmetrically

Treatment

Adjunctive therapy Patient should be offered with occupational therapy, this include training on how to avoid injury to insensitive skin of the hands and feet and special shoes may be required.

Prevention BCG (alone) –provide about 34% protection against infection BCG with heat killed M. leprae –increases the protection to 64%. ICRC vaccination was 65% effective. Chemoprophylaxis with once yearly for hyperendemic regions –multidrug therapy with single-dose rifampin, minocycline and clofazamine

Leprosy type Features Tuberculoid * Can be either one large red patch with well-defined raised borders or a large hypopigmented asymmetrical spot * Lesions become dry and hairless * Loss of sensation may occur at site of some lesions * Tender, thickened nerves with subsequent loss of function are common * Spontaneous resolution may occur in a few years or it may progress to borderline or rarely lepromatous types Borderline tuberculoid * Similar to tuberculoid type except that lesions are smaller and more numerous * Disease may stay in this stage or convert back to tuberculoid form, or progress Borderline borderline * Numerous, red, irregularly shaped plaques * Sensory loss is moderate * Disease may stay in this stage, improve or worsen Borderline lepromatous * Numerous lesions of all kinds, plaques, macules, papules and nodules. Lesions looking like inverted saucers are common * Hair growth and sensation are usually not impaired over the lesions Lepromatous * Early nerve involvement may go unnoticed * Numerous lesions of all kinds, plaques, macules, papules and nodules * Early symptoms include nasal stuffiness, discharge and bleeding, and swelling of the legs and ankles * Left untreated, the following problems may occur: o Skin thickens over forehead (leonine facies), eyebrows and eyelashes are lost, nose becomes misshapen or collapses, ear lobes thicken, upper incisor teeth fall out o Eye involvement causing photophobia (light sensitivity), glaucoma and blindness o Skin on legs thickens and forms ulcers when nodules break down o Testicles shrivel causing sterility and enlarged breasts (males) o Internal organ infection causing enlarged liver and lymph nodes o Voice becomes hoarse due to involvement of the larynx o Slow scarring of peripheral nerves resulting in nerve thickening and sensory loss. Fingers and toes become deformed due to painless repeated trauma.