TMSS Medical College Journal

Tuberculosis is considered as ubiquitous disease as it involves any organ, but involvement of skin is very rare; less than 1% of all tuberculosis today manifests as primary inoculation tuberculosis. In most cases, involvement is secondary and is caused by extension from underlying contiguous tuberculous structure. Primary inoculation tuberculosis of skin resulting from direct inoculation by pricking injury is a rare entity, the most notable example of primary inoculation tuberculos is the prosector's wart acquired by pathologists and their assistants from inoculation by tuberculous cadaver. We are reporting 4 cases of Primary inoculation tuberculosis following pricking injury without any evidence of pulmonary or skeletal tuberculosis in apparently healthy individual with no past history of contact or previous antituberculous therapy presented with painless, fluctuating, non warm masses of variable sizes 6-24 weeks after pricking injuries. Bacteriologically acid fast bacilli in Ziehl-Neelsen stain and histopathologically granulomata with epithelioid cells and variable areas of cascation necrosis were observed. All improved with surgery followed by standard antitubercular medications and no evidence of recurrence or other organ involvement was observed at 1-year follow-up visit.

Primary inoculation tuberculosis typically follows direct introduction of mycobacterium into skin or mucosa of a person by trauma or injury without immunity detected against the organism and was first documented in 1826;  when Laennec reported his own Prosector's wart!, Tuberculosis involvement of skin is very rare; less than 1% of all tuberculosis today manifests as primary  inoculation tuberculosis where extrapulmonary constitutes  about 10% 23, Furthermore, nowadays it is rare to find in  immunocompetent rather than non-immunocompetent patients. It can present in various forms depending on the mechanism of propagation, bacterial load implicated,  virulence of bacilli and the host's immune status, Clinical  findings vary; localizes papules, verrucous plaques, suppurative nodules, efronic ulcer, or other lesions may be seen. Detailed history and physical examination, Routine  blood test, Ziehl-Neelsen stain for identification of acid-  fast bacilli (AFB), Fine needle aspiration cytology (FNAC), Culture (Lowenstein-Jensen medium) of pus  and histopathological examination of abscess wall were performed for all patients to make diagnosis. To rule out pulmonary tuberculosis, chest X-ray was taken for all patients. Primary inoculation tuberculosis has been reported following tattoo, scalpel injury, accidental needle stick injury, acupuncture, intralesional steroid injection,  after BCG (Bacillus Calmette-Guerin) vaccination and  following vehicular accidents. Here, we are reporting 4 cases of primary inoculation tuberculosis resulting from pricking injury by stick broom (2), intramuscular injection  (1) and nail (1) presenting as cold abscess.