A 59-year-old man developed a giant, yellow wart on his hand, caused by a rare form of tuberculosis. The unusual case was reported in the Journal of the American Academy of Dermatology. The patient had been suffering from pain emanating from the wart for a year before seeking medical attention. The wart covered the top of his right hand and part of his right index finger, characterized by a thick yellow-brown crust.
Doctors performed a biopsy and examined the tissue under a microscope. They observed abnormal cell growth and clusters of cells known as tuberculoid granulomas, a typical response to Mycobacterium tuberculosis, the bacterium that causes TB. These granulomas form to contain the bacteria and prevent its spread. The biopsy confirmed the presence of Mycobacterium tuberculosis and tested positive for TB using a protein test.
While most tuberculosis infections affect the lungs, this patient had extrapulmonary TB, a rarer form that impacts other organs. Even rarer, his case was one of those where the skin was specifically affected, a condition called tuberculosis verrucosa cutis. This occurs when Mycobacterium tuberculosis enters the skin of someone previously exposed to the bacteria, often through minor cuts or abrasions. Patients typically develop warts at the site of infection, commonly on hands, knees, or ankles.
The authors of the case report did not discuss how the man contracted the infection. However, they noted his profession as a veterinarian, suggesting a potential risk factor. Exposure to mycobacteria in occupational settings, particularly involving frequent contact with livestock, can increase the risk of developing TB.
Tuberculosis verrucosa cutis, like pulmonary TB, is treatable with antibiotics. The patient was prescribed a six-month course of medication, and within two months, the wart had significantly reduced. Despite its rarity, this case highlights the importance of early diagnosis and treatment for all forms of tuberculosis, including extrapulmonary TB. The case also underscores the potential risks associated with certain occupations, particularly those involving contact with animals.
