Leprosy

What Is Leprosy?

Leprosy is a long-term infectious disease that mainly affects the skin and the peripheral nerves (nerves outside the brain and the spinal cord). It can also affect the mucosal layers of the eyes and nose. Hansen's disease can affect individuals in all age groups including infants and the elderly.

Alternate names

• Hansen's disease

Is this a medical emergency?

Leprosy is not a medical emergency.

Types of this condition

• Paucibacillary leprosy: This is also called tuberculoid leprosy. This is the milder form of Hansen's disease and is less contagious. Symptoms include pale skin patches with loss of sensation due to nerve damage underneath the skin.
• Multibacillary leprosy: This is also called lepromatous leprosy. This is a severe form of Hansen's disease and is more contagious. Symptoms include skin bumps, nodules, and thickened skin. It frequently affects the nose, kidneys, and male reproductive organs. Advanced cases of leprosy can also cause loss of eyebrows and eyelashes.
• Borderline leprosy: This is the most common form of Hansen's disease with intermediate severity of the disease. This type of leprosy is unstable. It can either progress to lepromatous leprosy or it can decrease to tuberculoid leprosy.

Causes of leprosy

Leprosy is caused by a slow-growing bacterium called Mycobacterium leprae and Mycobacterium lepromatosis. The period between contact with the bacteria and the appearance of the symptoms is called the incubation period. Symptoms of Hansen's disease can occur either in the first year or up to 20 years after the onset. So it is difficult to determine when and how a person got infected.

Transmission of the disease

Hansen's disease is spread through coughing or coming in contact with the nasal secretions of an infected person. Leprosy does not spread through sexual contact or from mother to fetus. Hansen's disease is not spread through touch or skin-to-skin contact.

Risk factors for Leprosy

Factors that increase the risk of developing Hansen's disease include:

• Living in close contact with the infected person
• Living in regions where leprosy is endemic

Symptoms & signs of Leprosy

Signs and symptoms of leprosy can occur either in the first year or up to 20 years after the initial infection. They include the following:

• Runny nose
• Dry scalp
• Eyes and speech deformities
• Painless skin patches
• Disfiguring skin sores and bumps
• Thickening of facial skin, ear, and hands
• Ulceration of hands and feet
• Loss of sensation or paresthesia in fingers and toes
• Destruction of nasal cartilage resulting in a flat nose
• Wasting and muscle weakness
• Clawed hands
• Shortened and deformed fingers and toes due to tissue loss

Investigations

• Skin smears: A sample tissue of the affected skin is taken and tested for acid-fast bacilli
• Nasal smears: A sample of nasal secretion is collected and tested for acid-fast bacilli
• Other immunologic tests: Immunologic tests such as serologic assays, Polymerase Chain Reaction (PCR), Lymphocyte Migration Inhibition Test (LMIT) are also performed.

Diagnosis of Leprosy

The diagnosis of Hansen's disease is made depending on the following findings:

• Identifying pale or reddish skin lesions with loss of sensation
• Thickened peripheral nerves and loss of sensation
• Positive skin smear test for acid-fast bacilli

Leprosy treatment options

A. Medical treatment

The medical treatment of Hansen's disease includes multi-drug therapy

• Anti-leprosy medication: A multi-drug regimen of rifampicin, dapsone, and clofazimine is prescribed for 6 months for individuals suffering from paucibacillary leprosy and for 12 months for individuals suffering from multibacillary leprosy.
• Rifampicin-resistant leprosy is treated with drugs such as fluoroquinolones, minocycline, or clarithromycin
• Topical ketanserin is used for healing ulcers
• Corticosteroids are used to treat nerve damage

B. Interventional treatment including surgery and indications for surgery/surgical treatment

There is no complete surgical procedure to cure Hansen's disease. Surgical procedures are performed to improve motor function, sensation, and prevent further worsening of the condition.

• Several neural surgeries are done to reduce pressure on the nerves, improve sensation, relieve nerve compression, and relieve pain
• Procedures like Z-Plasty and tenodesis are performed to relieve contractures and improve joint stability
• Amputations are done to remove extremely diseased tissues
• Eye procedures are performed to correct the eye deformities
• Cosmetic surgeries like nasal reconstruction, removal of excess skin, eyebrow replacement, etc, are also performed

C. Role of diet/exercise/lifestyle changes/preventive measures

Treatment like protective footwear (canvas shoes) can prevent ulcers and other infections Preventive measures of Hansen's disease include:

• Early detection of the disease and early treatment measures
• A single dose of rifampicin is administrated as preventive medicine
• BCG (Bacillus Calmette–Guérin) vaccine protects against Hansen's disease

Complications of leprosy

Hansen's disease leads to the following complications:

• Damage to nerves that causes loss of muscle function, leading to paralysis
• Damage to the respiratory tract, leading to nasal congestion and nose bleeds
• Damage to skin and eyes. It can cause blindness or glaucoma
• Disfiguration of the face
• Kidney damage
• Erectile dysfunction
• Muscle weakness, inability to flex, and formation of claw-like hands

Prognosis

The skin deformities caused due to Hansen's disease can be cured; however, the nerve damage is irreversible. Although surgical treatments like reconstructive surgery, nerve transplants, the release of contractures, and physical therapy can improve the quality of life, the overall prognosis of Hansen's disease is poor.

When to contact the doctor/How to identify complications?

On observing any changes on the skin, changes in sensation, and motor function, a medical consultation is warranted.

Indications for hospitalization if required

Hospitalization will be required if surgical interventions are warranted for the management of Hansen's disease.

Suggested clinical specialists/Departments to consult for this condition

• Dermatology
• Infectious Disease
• Neurology