A 71-year-old woman with a rash due to cutaneous TB. In most cases TB affects the lungs, but in some cases it affects the skin, causing this rash. This form of the disease can cause ulceration and destruction of underlying cartilage. In many countries TB has been largely controlled through vaccination programs, but a recent resurgence in disease is attributable to relaxation of these programs along with economic migration.
A positive Mantoux skin test, indicating that a person has TB. Test results must be interpreted carefully, as medical risk factors determine the increment of induration that indicates whether a test is positive.
Doctors compare lung x-rays of a patient with TB (left) and a healthy patient (right).
A large ulcerated TB lesion on the face of a young black woman. Primary infection almost always occurs in the lungs, from where it may spread to nearby lymph nodes. If left untreated, infection may enter the bloodstream and spread throughout the body, causing milliary tuberculosis. Lesions affecting the bones, kidneys and skin are usually signs of advanced disease, occurring several years after the initial infection.
Red patches on the legs of a 38-year-old woman caused by TB. Nodular vasculitis is an inflammation of fatty tissues beneath the skin
Bacillus Calmette-Guérin vaccine
Close-up of a papule forming a scar on the skin in an 8-year-old boy two months after receiving Bacillus Calmette-Guérin TB vaccination. BCG vaccine is not commonly administered in the United States because of the relatively low risk for infection and the vaccine’s potential to interfere with skin-test reactivity.
Tuberculosis is an infectious disease caused by Mycobacterium tuberculosis. It commonly affects the lungs, but can spread to the bone, brains, liver, kidney and heart, and can be fatal if left untreated. The disease is transmitted person to person via fomites in coughs and sneezes. Although once uncommon in developed countries, TB rates have been increasing due to more frequent international travel, the emergence of drug resistant strains and it’s presence as a concurrent infection in patients with AIDS.