Related Experiment Video
Updated: Aug 13, 2026

Deciphering and Imaging Pathogenesis and Cording of Mycobacterium abscessus in Zebrafish Embryos
Published on: September 9, 2015
Papulonecrotic tuberculid secondary to disseminated Mycobacterium avium complex
J T Williams1, D R Pulitzer, R L DeVillez
1Department of Pathology, University of Texas Health Science Center, San Antonio 78284.
Background:
Papulonecrotic tuberculid is a rarely reported cutaneous reaction to the mycobacterium bacillus. It is most often encountered in association with tuberculosis. The clinical and histologic picture of the entity is a distinctive one, but the etiology of the disease process is uncertain. Therapy directed against the causative organism is dramatically successful.
Methods:
A 35-year-old white man with AIDS was referred to the Dermatology clinic for evaluation of a widespread skin eruption. The skin lesions were biopsied for histopathology and culture. From the cutaneous cultures Mycobacterium avium complex (MAC) organisms were grown.
Results:
We report the first case of papulonecrotic tuberculid manifestation in an AIDS patient with disseminated MAC. Unusual features seen in this case include the predominance of pruritic eschars rather than asymptomatic papules and the confirmation by special stains of mycobacterium organisms within the skin biopsy. Papulonecrotic tuberculid has not been previously associated with either MAC or AIDS.
Conclusions:
Papulonecrotic tuberculid should be a diagnostic consideration in immunocompromised patients with MAC whose clinical and histologic features are compatible with this rare entity.
Related Concept Videos
Pulmonary Tuberculosis I
Causative Organism
The primary infectious agent causing tuberculosis is Mycobacterium tuberculosis, a slow-growing, acid-fast, aerobic rod that exhibits sensitivity to heat and ultraviolet light. Instances of Mycobacterium bovis and Mycobacterium avium contributing to the development of TB infection are rare.
Mode of...
Pulmonary Tuberculosis II
Here is a detailed explanation of its pathophysiology:
Transmission: The process begins when a person inhales droplet nuclei containing M. tuberculosis. These are typically released into the air when an individual with pulmonary or...
Pulmonary Tuberculosis III
The first classification is based on the development of the disease, and it includes the following categories:
Pulmonary Tuberculosis IV
Several diagnostic approaches are used to detect TB. The conventional method is the Tuberculin Skin Test (TST), also known as the Mantoux test. However, this method has...
Tuberculosis
Cryptococcal Meningitis

