Leprosy is one of the oldest diseases known to mankind, with the first known written
reference dating back to 600 B.C. Leprosy is a chronic infectious disease caused by the slow-multiplying bacterium Mycobacterium leprae. It affects the nervous and immune systems, leading to severe sores and nerve damage in the skin and causing disability and disfiguration. It is more common tropical and subtropical countries such as India.
Contrary to the popular perception, Leprosy is not very contagious. It only spreads if a
person comes in contact with mucus droplets of an affected person, which usually happens when the latter coughs or sneezes. Children are more likely to get infected than adults. Leprosy has a a relatively large incubation period (the time between the infection and appearance of the first symptoms) which can extend up to five years. Sometimes, symptoms may take as much as 20 years to appear. It starts by damaging the nerves present on the surface of the skin, leading to discoloured patches which may not feel much. Gradually, it can progress and damage the nerves in other parts of the body such as the eyes, muscles, bones etc. and also cause a loss of sensation in the limbs.
Types of Leprosy:
There are many systems of classification of leprosy. We will consider the one where the
type is determined by the person’s immune response to the disease. Going by this, there are two types of leprosy:
1. Tuberculoid Leprosy: This is a mild form of the disease. A person infected with this type of leprosy will have few lesions and sores. The affected areas of the skin may feel numb due to nerve damage underneath. This is only mildly contagious.
2. Lepromatous Leprosy: This is a more severe form of leprosy. The person will have many lesions and rashes accompanied by numbness and muscle weakness. It can result in disfigurement. It is more contagious than tuberculoid leprosy.
The primary symptoms of leprosy are:
- Discoloured skin lesions which have a reduced sensation to inputs like touch,
temperature or pain.
- Muscle weakness
- Eye problems and difficulty in blinking which may lead to blindness
- Severe pain
- Enlarged nerves, especially around the elbows and the knees
- Numbness in the limbs
- Loss of fingers and toes
The doctor will conduct a physical examination to look for signs and symptoms of
leprosy. If you have a suspicious skin sore, the doctor may remove a sample of the affected skin and send it to the lab for futher analysis. This is called a skin biopsy.
Another method of diagnosis is the skin smear test, in which a sample of material is
collected from a tiny cut in the skin and stained for the leprosy-causing bacteria.
A lepromin skin test may also be performed to determine the type of leprosy. In this
test, a small amount of Mycobacterium leprae is injected into the skin. People infected with tuberculoid leprosy will experience irritation at the site of the injection.
Treatment involves medications along with supportive care. A long-term treatment plan
ranging from six months to an year with antibiotics is recommended. Some of the antibiotics which helps in curing leprosy are dapsone, rifampin, clofazamine, minocycline and ofloxacin. In rare cases, there may be some side-effects of leprosy treatment which inclufe minor anaemia, slight darkening of the skin that disappears once the treatment is stopped and abnormal liver test results which may produce a harmless, orange discoloration of sweat, urine or tears. Anti-inflammatory medicines such as aspirin, prednisone etc. may also be given to control nerve pain and damage.
Women who are pregnant or planning to become pregnant should not take
thalidomide, which is also a medication for leprosy that suppresses the body’s immune system, as it causes life-threatening birth defects.
Early detection and treatment is important for curing leprosy as it can help prevent
tissue damage and other health complications. Once the person becomes disfigured or some sort of disability sets in, leading a normal life may be impossible despite treatment.