Mycobacterial Skin and Soft Tissue Infection

Abstract

Mycobacterial skin and soft tissue infection (SSTI) includes nontuberculous mycobacterial (NTM) infections, tuberculosis (TB), and leprosy. Diagnosis of mycobacterial SSTI can be challenging due to diverse clinical presentation, low yield from cultured specimens, and nonspecific histopathology on tissue biopsy. In addition, immunosuppressed patients may present with atypical or disseminated disease. Despite aggressive medical treatment and often with surgical intervention, results may be suboptimal with poor outcomes. Regimens typically require multiple antibiotics for extended periods of time and are often complicated by medication side effects and drug-drug interactions. Biopsy with culture is the gold standard for diagnosis, but newer molecular diagnostics and proteomics such as matrix-assisted laser desorption ionization-time of flight mass spectrometry have improved diagnosis with increased identification of clinically significant mycobacteria species in clinically relevant time frames. We will review updates in diagnostic tests along with clinical presentation and treatment of mycobacterial SSTI for NTM, TB, and leprosy.

Verrucose tuberculosis cutis associated with chronic monoartritis of knee in a patient with HIV infection

“…10 It is a priority to consider as a differential diagnosis other granulomatous pathologies such as sarcoidosis, leprosy, leishmaniasis, fungal infections (erysipelothrix rhusiopathiae), Majocchi granuloma and carcinoma. 11 The presence of granulomatous infiltrates in the The presence of chronic monoarthritis with studies of synovial fluid compatible with tuberculous arthritis in the context of a patient with verrucous tuberculosis on the back of the hand reinforces the theory of hematic dissemination of mycobacteria from primary cutaneous infection to the joint of the knee. 10,12 The appearance of new diagnostic methods such as the detection of lipoarabinomannan antigen from the tubercle bacillus removed by urine is a rapid method of great diagnostic support, which has been validated in patients with HIV infection, but with few studies in immunocompetent In the case presented, this immunochromatographic test was performed, which showed a positive result supporting the diagnosis of tuberculosis disease.…”

Cutaneous Mycobacterial Infections

“…From a large mycobacterial pool, some species have evolved into potential major human pathogens (20,(23)(24)(25) (Fig. 1).…”

“…In the human host, mycobacterial infections may affect many anatomical sites, but since they enter through the skin and mucosal barriers, they lead mostly to pulmonary or cutaneous infections (25)(26)(27)(28). The pathogenesis of cutaneous mycobacterial infections is the result of hematogenous dissemination, local or regional spread from a deep-seated infection, or direct inoculation into the skin and soft tissues (24). The modes of transmission of the different mycobacterial species involved in cutaneous disease include zoonotic transmission (e.g., foodborne transmission of Mycobacterium bovis by ingestion of unpasteurized dairy products) (16, 1).…”

“…Free-living amoebas, including Acanthamoeba or Vermamoeba, may act as reservoirs of M. leprae and NTM (38)(39)(40)(41). The most common cutaneous forms of acquisition of NTM involve direct inoculation via trauma (33), postsurgical infections (42), or iatrogenic acquisition with indwelling medical devices, plastic surgery, cosmetic procedures, or prosthetic implants (24,42). Mycobacteria may seed the skin and soft tissues during systemic dissemination in immunosuppressed individuals (24,25,37,(42)(43)(44).…”

“…2) (47,69). The differential diagnosis of cutaneous TB includes other granulomatous conditions, including sarcoidosis, leprosy, leishmaniasis, fungal conditions (blastomycosis and chromoblastomycosis), Majocchi's granuloma, halogenoderma, squamous cell carcinomas, orf disease (parapox virus), and syphilis (24,47).…”