Leprosy (Hansen's disease):

Leprosy (Hansen's disease)

Leprosy is a chronic, progressive bacterial infection caused by the bacterium Mycobacterium leprae. It primarily affects the nerves of the extremities, the skin, the lining of the nose, and the upper respiratory tract. Leprosy is also known as Hansen’s disease.

Hansen’s disease produces skin ulcers, nerve damage, and muscle weakness. If it isn’t treated, it can cause severe disfigurement and significant disability. Hansen’s disease is common in many countries, especially those with tropical or subtropical climates. It’s not very common in the United States. The Centers for Disease Control and Prevention (CDC) reports that only 150 to 250 new cases are diagnosed in the United States each year.

Types

There are three main types of leprosy, including:

Tuberculoid leprosy: Someone with this type of leprosy usually has mild symptoms, developing only a few sores. This is because of a good immune response. Tuberculoid leprosy is also called paucibacillary leprosy.

Lepromatous leprosy: People with this type of leprosy have widespread sores and lesions affecting nerves, skin and organs. With lepromatous leprosy, the immune response is poor and the disease is more contagious. Lepromatous leprosy is also called multibacillary leprosy.

Borderline leprosy: This type of leprosy involves symptoms of both tuberculoid and lepromatous leprosy. Borderline leprosy is also called dimorphus leprosy.

Causes 

Leprosy is caused by a slow-growing type of bacteria called Mycobacterium leprae (M. leprae). It isn’t clear exactly how leprosy is transmitted. When a person with leprosy coughs or sneezes, they may spread droplets containing the M. leprae bacteria that another person breathes in. Close physical contact with an infected person is necessary to transmit leprosy. It isn’t spread by casual contact with an infected person, like shaking hands, hugging, or sitting next to them on a bus or at a table during a meal. Pregnant mothers with leprosy can’t pass it to their unborn babies. It’s not transmitted by sexual contact either.

Signs and Symptoms

Symptoms mainly affect the skin, nerves, and mucous membranes (the soft, moist areas just inside the body’s openings). The disease can cause skin symptoms such as:

• A large, discolored lesion on the chest of a person with Hansen’s disease.
• Discolored patches of skin, usually flat, that may be numb and look faded (lighter than the skin around)
• Growths (nodules) on the skin
• Thick, stiff or dry skin
• Painless ulcers on the soles of feet
• Painless swelling or lumps on the face or earlobes
• Loss of eyebrows or eyelashes
• Symptoms caused by damage to the nerves are:
• Numbness of affected areas of the skin
• Muscle weakness or paralysis (especially in the hands and feet)
• Enlarged nerves (especially those around the elbow and knee and in the sides of the neck)
• Eye problems that may lead to blindness (when facial nerves are affected)

Symptoms caused by the disease in the mucous membranes are:

• A stuffy nose
• Nosebleeds

Since Hansen’s disease affects the nerves, loss of feeling or sensation can occur. When loss of sensation occurs, injuries such as burns may go unnoticed. Because you may not feel the pain that can warn you of harm to your body, take extra caution to ensure the affected parts of your body are not injured.

If left untreated, the signs of advanced leprosy can include:

• Paralysis and crippling of hands and feet
• Shortening of toes and fingers due to reabsorption
• Chronic non-healing ulcers on the bottoms of the feet
• Blindness
• Loss of eyebrows
• Nose disfigurement
• Other complications that may sometimes occur are:
• Painful or tender nerves
• Redness and pain around the affected area
• Burning sensation in the skin

Diagnosis

If your healthcare provider thinks you might have Hansen's disease (leprosy), they’ll perform a skin biopsy. During this procedure, they’ll take a small sample of tissue and send it to a lab for analysis.

Note: Continue a 100 percent evaluation beyond the cessation of treatment for active disease. Six months after discontinuance of such treatment, determine the appropriate disability rating by mandatory VA examination. Any change in evaluation based upon that or any subsequent examination shall be subject to the provisions of §3.105(e) of this chapter. Thereafter, rate under the appropriate body system any residual disability of infection, which includes, but is not limited to, skin lesions, peripheral neuropathy, or amputations.