Leprosy

Symptoms: Discoloured patches of skin, muscle weakness, numbness of affected areas of the skin, painful ulcers on the soles of feet

Causes: Mycobacterium leprae (bacteria)

Risk Factors: Close contact with a person infected with leprosy, living in poverty

Prevalence: Worldwide-174,087 new cases, India- 75,394 new cases

Severity: Mild to severe

Which doctor to consult: Dermatologist, Infectious disease specialist, Internal medicine specialist, Neurologist

Overview:

Leprosy, also known as Hansen’s disease, is a chronic infectious disease caused by bacteria called Mycobacterium leprae. It affects the peripheral nerves, skin, eyes, and mucosal surfaces of the upper respiratory tract. Leprosy can strike anyone at any age, from young children to the elderly. 

Leprosy symptoms may occur within a year but can also potentially take up to 20 years or longer. The main symptoms include skin lesions, muscle weakness and numbness in the arms, hands, legs and feet.

Leprosy is spread by droplets from the mouth and nose during close and frequent contact with untreated individuals. After starting treatment, the patient is no longer contagious.

Leprosy is curable, and treatment in the early stages of the disease can avoid disability. If it is left untreated, the nerve damage might cause paralysis in the hands and feet. In very advanced cases, the person may have many injuries due to lack of sensation and may cause shortening of fingers and toes due to reabsorption.

Types of Leprosy:

Based on the type and number of affected skin areas, Leprosy is categorised into the following:

Paucibacillary leprosy: A person has 1 to 5 skin lesions, and no bacteria are detected in skin samples.

Multibacillary leprosy: A person has more than 5 skin lesions, and the bacteria are present in a skin smear.

Symptoms:

The symptoms of leprosy mainly affect the nerves, skin, and mucous membranes (the soft, moist areas just inside the body’s openings). The symptoms include:

• Discoloured patches of skin

• Dry, thick or stiff skin

• Nodules (growths) on the skin

• Painless ulcers on the soles of feet

• Numbness of affected areas of the skin

• Muscle weakness

• Stuffy nose

• Nosebleeds

Causes:

Leprosy is caused by a slow-growing bacteria called Mycobacterium leprae. It damages the peripheral nerves and targets the skin, nose, eyes, and mucosal surfaces of the respiratory tract. Leprosy is transmitted through droplets from the mouth and nose and months of close, prolonged contact with someone with untreated leprosy. 

Risk Factors:

All adults worldwide have a very low chance of contracting Hansen's disease. This is due to the fact that over 95% of individuals possess natural immunity to the illness. However, the risk factors associated with Leprosy include:

Living in endemic areas: People living in areas where leprosy is endemic (a disease that is constantly present in a specific population or geographic area) along with poor nutritional status and poor hygiene, such as Nepal, India, Brazil, Madagascar, Mozambique, Central African Republic, United Republic of Tanzania and other areas. 

Close contact: Prolonged close contact with an untreated leprosy patient may increase the risk of getting leprosy.

Immunosuppression: Leprosy usually occurs when immunity is suppressed, like after HIV infection.

Genetic risk factors: There are innate (inborn) and acquired components to the immune response directed against the mycobacteria. Variants of the innate component's regulator, the NOD2-mediated signalling pathway, have been found to be more susceptible to leprosy.

Age: Leprosy incidence has a bimodal distribution, with an increase in frequency between the ages of 5 and 15 and then another increase beyond 30 years of age.

Armadillo contact: Disease is stored by armadillos, and contact with armadillo increases the disease transmission risk.

Possible Complications:

Delayed diagnosis and treatment may lead to complications of leprosy, which include:

• Nose disfigurement

• Paralysis and crippling of feet and hands

• Loss of sensation

• Fingers and toes shortening due to reabsorption

• Loss of eyebrows

• Blindness

• Chronic non-healing ulcers on the bottoms of the feet

• Tender or painful nerves

Prevention:

The best approach to prevent leprosy is to avoid long-term, close contact with an untreated individual who has the infection.

When to see a doctor?

If you notice lesions on your skin and feel loss of sensation or have any other symptoms of leprosy, please consult a doctor, as treatment in the early stages can prevent disability.

Diagnosis:

Leprosy can be diagnosed by the appearance of skin patches that may look darker or lighter than the normal skin or reddish, loss of sensation in these patches, and enlarged or thickened peripheral nerve, with loss of sensation or weakness in the muscles supplied by that nerve.

Microscopic detection of bacteria in a slit-smear test: To confirm the diagnosis, your doctor will take a sample of your nerve or skin (through a nerve or skin biopsy) to look for the bacteria under a microscope and may also run tests to rule out other skin diseases.

Treatment:

Leprosy is treated with a combination of antibiotics known as multi-drug therapy (MDT). 

Antibiotics: The currently recommended multi-drug therapy (MDT) includes a 3-drug regimen: 

• Dapsone 

• Clofazimine

• Rifampicin

For Paucibacillary leprosy patients, the duration of treatment is 6 months, and for Multibacillary leprosy cases, it is 12 months.

Home Remedies:

Home care helps to minimize the risk of serious complications of leprosy. The use of assistive devices, proper wound care, and other preventative measures may help leprosy patients manage their impairments and prevent them from worsening. Self-care for leprosy includes the following:

• Use preventive methods when performing daily life activities (e.g. use a cloth when picking up a hot pan or blinking the eyes frequently to prevent dryness).

• Soak hands and feet in lukewarm water. Apply oil and take care to avoid dry and cracked skin.

• Do stretching exercises to prevent stiffness and contractures (permanent tightening of muscles, tendons, skin and nearby tissues).

• Check for wounds and infections which are not caused by nerve damage.