Diagnosis of mycobacterial skin infections

Abstract

Summary The diagnosis of cutaneous mycobacterial infections may be challenging. Owing to the broad spectrum of their clinical presentations, mycobacterioses have to be considered as differential diagnoses to many inflammatory dermatoses. Diagnostic measures comprise histology including special staining, cultures and molecular microbiological examinations as well as the detection of cellular immune reactions of the patient by means of interferon‐γ release assays and skin testing. Clinicians should know the appropriate use and combination of procedures to diagnose mycobacterioses quickly and correctly and to avoid costs and delays caused by unnecessary examinations. This mini review summarizes advantages, limitations, and pitfalls of diagnostic methods for mycobacterial skin infections.

Histoid leprosy in a young man

“…The histopathology of HL consists of atrophied epidermis due to expansion of the dermis by the underlying leproma, which is made up of foamy, polygonal and vacuolated histiocytes arranged in a tangled or storiform pattern and surrounded by a pseudocapsule. In HL, the AFB have a tendency to align themselves along the long axis of the histiocytes, which is known as the histoid habitus [2,8].…”

Mycobacterium ulcerans and Mycobacterium marinum: Pathogenesis, Diagnosis and Treatment

“…Incubation of both solid and liquid media at both 30 o C and 35 o C are usually done to optimally recover the NTM. Different media compositions and conditions according based on specific NTM metabolic needs are also required for their isolation, hence the suspected mycobacterial species could be suggested by the clinicians based on source of exposure and the clinical symptoms to the microbiologists [25] .…”

“…However, the detection of acid-fast rod-like bacteria is unusual. Meanwhile, M. ulcerans infections are associated with septal subcutaneous necrosis of adiposerich tissue and positive for acid-fast bacteria detection [25] .…”

Kutane Infektion mit Mycobacterium hämophilum bei einem immunkompetenten Patienten

“…Hautinfektionen mit Mycobacterium haemophilum sind nach wie vor eine diagnostische Herausforderung. Zu den diagnostischen Maßnahmen gehören histologische Aufarbeitung, Kultivierung und molekularmikrobiologische Untersuchungen [ 8 ] . Da die histomorphologischen Befunde bei verschiedenen Erregern sehr ähnlich ausfallen können, hängt die defi nitive Diagnose vom Nachweis der Mykobakterien ab [ 9 ] .…”