Detection of Nontuberculous Mycobacterial Skin Infection by Next-Generation Sequencing: A Pilot Study

Area of Science:

• Medical Microbiology
• Genomics
• Dermatology

Background:

• Nontuberculous mycobacteria (NTM) skin infections present diagnostic challenges due to nonspecific clinical and histopathological features.
• Conventional pathogen detection methods for NTM infections have limitations.
• Metagenomic next-generation sequencing (mNGS) shows promise for diagnosing NTM infections but requires further evaluation.

Purpose of the Study:

• To evaluate the utility of mNGS in diagnosing cutaneous NTM infections.
• To compare the diagnostic performance of mNGS with conventional culture methods.
• To correlate clinical presentation and exposure history with specific NTM species.

Main Methods:

• Prospective pilot study involving 20 patients with confirmed cutaneous NTM infection.
• Clinical assessment, skin biopsy for histopathology and culture, and mNGS of skin tissue were performed.
• Treatment was guided by identified NTM species and disease extent, with outcomes tracked.

Main Results:

• mNGS demonstrated a higher positivity rate (95%) and faster turnaround time than conventional culture (30%) for NTM detection.
• *Mycobacterium marinum* (12/20) and *M. abscessus* (4/20) were the predominant pathogens identified.
• Treatment success was achieved in 85% of patients with tailored antibiotic regimens, despite adverse drug effects in some.

Conclusions:

• mNGS offers a more rapid and sensitive diagnostic approach for cutaneous NTM infections compared to traditional culture.
• Clinical features and exposure history are valuable in predicting specific NTM species involved in skin infections.
• Integrating mNGS with clinical assessment enhances the diagnosis and management of NTM skin infections.