Abstract: Mycobacterium smegmatis belongs to type IV (rapid growth) non-tuberculous mycobacteria. It is widely distributed in the natural environment and can exist normally in the skin and mucous membranes. When the immunity of the body is weakened or the normal skin and mucous membranes are damaged. It can become an opportunistic pathogen. There are few cases of Mycobacterium smegmatis infection reported, the incidence is low, and it is easy to be missed clinically. Pathogenic microorganism high-throughput sequencing technology (next-generation sequencing technology, NGS) can extract hundreds of thousands to millions of DNA and RNA molecules at a time. The application of this technology enables clinicians to identify pathogens of infectious diseases. Screening can detect pathogens earlier, achieve the purpose of early diagnosis and early treatment, and greatly improve the diagnosis rate of difficult infectious diseases. In this paper, a case of Mycobacterium smegmatis infection was diagnosed by blood NGS detection to report and review the literature, in order to improve the ability of diagnosis and treatment of Mycobacterium smegmatis infection.

Key words: Fever of unknown, Nontuberculous mycobacteria, Mycobacterium smegmatis, High-throughput sequencing of pathogenic microorganisms