Skin TB, also known as cutaneous tuberculosis, is a rare form of tuberculosis (TB) that affects the skin. It's caused by the same bacteria as lung TB, Mycobacterium tuberculosis. Unlike lung TB, which primarily affects the lungs, skin TB manifests as various skin lesions. These can range from rashes and bumps to ulcers and nodules. The infection can spread through direct contact with an infected person or through autoinoculation (self-infection from another part of the body).
Understanding Skin TB
- Cause: Mycobacterium tuberculosis, the same bacteria responsible for pulmonary (lung) tuberculosis.
- Transmission: Direct contact with an infected person or through autoinoculation.
- Symptoms: A variety of skin manifestations, including rashes, bumps, lesions, and ulcers. Specific symptoms vary depending on the type of skin TB.
- Rarity: Cutaneous tuberculosis is considered a rare condition.
Types of Skin TB
While there are several types of cutaneous tuberculosis, some common presentations include:
- Lupus vulgaris: This is a chronic, slowly progressive form characterized by reddish-brown lesions.
- Scrofuloderma: This type involves infection of the lymph nodes, often resulting in nodules and ulcers on the skin.
- Tuberculides: These are skin lesions that develop as a result of a hypersensitivity reaction to tuberculosis elsewhere in the body.
Diagnosis and Treatment
Diagnosis typically involves a combination of physical examination, skin biopsy, and microbiological tests to confirm the presence of Mycobacterium tuberculosis. Treatment involves a course of antibiotics, similar to the treatment for pulmonary TB, but tailored to the specific presentation and severity of the skin infection.
Treatment is crucial; untreated active TB disease can be fatal. A tuberculin skin test (TST) or Mantoux test can detect latent TB infection but doesn't specifically diagnose skin TB.
Sources:
Information for this response was gathered from multiple sources including the CDC, Verywell Health, Healthline, and DermNet NZ. These sources detail the symptoms, causes, transmission, and treatment options for skin TB. The CDC's resources highlight the importance of proper diagnosis and treatment to prevent potentially fatal outcomes.
