Signs and Symptoms of Leprosy

Leprosy, also called Hansen's disease, is a chronic infectious disease caused by Mycobacterium leprae bacteria. The disease develops slowly, and most people who contract the bacteria do not experience symptoms for at least a year. Typically it takes around 5 to 7 years for noticeable symptoms to develop, but it can sometimes take up to 30 years.

Leprosy primarily affects the skin, nerves in the hands and feet, and mucous membranes (moist, inner linings) of the eyes and nose. Untreated leprosy can lead to physical deformities, blindness, and kidney failure, among other complications.

Throughout history, leprosy has been surrounded by stigma and fear, often leading to social exclusion and isolation for those affected. But with early detection and timely treatment, leprosy is curable, and people affected by the disease can lead full lives.

Skin Symptoms

Skin symptoms of leprosy usually appear within the first 5-10 years of exposure. Patches of discolored skin that are usually lighter than your normal skin tone are often the first sign of leprosy. The skin can also present as erythematous, meaning it is abnormally red due to the accumulation of blood in dilated capillaries. Numbness of the affected skin is often detected during clinical evaluation, usually making it more difficult for you to distinguish between hot and cold.

Other skin-related leprosy symptoms include:

• Dry, thick, or stiff skin 
• Lumps or bumps on the skin, primarily on the face or earlobes
• Small nodules (growths) on the skin
• Loss of hair (alopecia) in affected areas of skin
• Loss of eyelashes or eyebrows 
• Painless ulcers on the soles of the feet, especially ulcers that don't heal over time

Over time, leprosy can cause permanent damage to the skin, as well as progress to tissue damage.

When leprosy affects the mucous membranes in the nose, other symptoms may develop, such as nose bleeds and a chronic stuffy nose.

Nerve Symptoms

Over time, leprosy can lead to nerve damage and cause a range of symptoms. Nerve involvement usually appears in later stages due to enlarged and peripheral nerves being affected by the skin lesions that appeared first. Nerve symptoms can include:

• Numbness or loss of sensation in the affected areas of the skin
• A burning sensation in the skin
• Tingling or "pins and needles" sensation (peripheral neuropathy)
• Muscle weakness 
• Loss of reflexes
• Paralysis (partial or complete loss of movement and sensation) or weakness in facial muscles, hands, or feet 
• Impaired vision or blindness due to damage to the optic nerves
• Chronic pain or discomfort in the affected nerves
  

Systemic and End-Stage Leprosy Symptoms

Severe, systemic infections involve infiltration of the Mycobacterium leprae bacteria to organs such as the testes and kidneys. People with this type of infection have more accompanying skin symptoms and are more contagious. Infection of the testes can lead to hormonal changes, potentially causing gynecomastia (enlargement of the breast tissue) in people assigned male at birth. Infection of the kidneys can cause kidney failure.

In the end stage of the disease, bone and cartilage can be absorbed into the body, causing deformities and even loss of your fingers, toes, and nose, among other limbs. This is known as auto-amputation.

Secondary infections can occur due to physical trauma, loss of sensation, and tissue loss. This is why it's important to seek treatment as soon as possible as well as treat any open wounds to help prevent infection.

When to See a Healthcare Provider 

Talk to a healthcare provider if you notice any unusual changes in your skin, such as discolored patches, lumps, or numbness. They will likely refer you to a dermatologist, or a medical doctor who specializes in the hair, skin, and nails. They will determine if leprosy or another condition is causing your symptoms. Early diagnosis and treatment of leprosy can kill the bacteria that cause the disease and help prevent complications.

A Quick Review 

Leprosy (Hansen's disease) is a chronic infectious disease caused by the Mycobacterium leprae bacteria. Symptoms typically develop slowly and often appear 5 to 7 years after exposure to the bacteria.

Leprosy primarily affects the skin, nerves, and mucous membranes (soft, moist tissues) in the nose and eyes. Common symptoms include discolored patches of skin, lumps or bumps on the skin, and numbness in the affected areas.

Untreated leprosy can lead to permanent nerve damage and may cause physical deformities on the hands and feet, muscle weakness, vision problems or blindness, and kidney failure. Leprosy is treatable, and early diagnosis can help prevent nerve damage and complications.