Mycobacteroides abscessus (formerly Mycobacterium abscessus) is a species of rapidly growing, multidrug-resistant, nontuberculous mycobacteria that is a common soil and water contaminant. Although M. abscessus most commonly causes chronic lung infection and skin and soft tissue infection (SSTI), it can also cause infection in almost all human organs, mostly in patients with suppressed immune systems. Amongst NTM species responsible for disease, infection caused by M. abscessus complex are more difficult to treat due to antimicrobial drug resistance. Description Mycobacteroides abscessus cells are Gram-positive, nonmotile, acid-fast rods about 1.0–2.5 µm long by 0.5 µm wide. They may form colonies on Löwenstein–Jensen medium that appear smooth or rough, white or greyish, and nonphotochromogenic. Etymology Abscessus is named for abscesses. It is a Latin word derived from ("away") + ("to go") because it was the ancient medical notion that a manifestation of the four humors was for pus to leave the body. M. abscessus was first isolated from gluteal abscesses in a 62-year-old patient who had injured her knee as a child and had a disseminated infection 48 years later. The species M. bolletii, which was first described in 2006, is named after the late eminent French microbiologist and taxonomist Claude Bollet. Physiology M. abscessus shows growth at 28 and 37 °C after 7 days, but not at 43 °C. It may grow on MacConkey agar at 28 °C and even 37 °C. It shows tolerance to saline media (5% NaCl) and 500 mg/L hydroxylamine (Ogawa egg medium) and 0.2% picrate (Sauton agar medium). Strains of the species have been shown to degrade the antibiotic p-aminosalicylate. M. abscessus has also been shown to produce arylsulfatase, but not of nitrate reductase and Tween 80 hydrolase. It shows a negative result for the iron uptake test and no use of fructose, glucose, oxalate, or citrate as sole carbon sources. Differential characteristics M. abscessus and M. chelonae can be distinguished from M. fortuitum or M. peregrinum by their failure to reduce nitrate and to take up iron. Tolerance to 5% NaCl in Löwenstein-Jensen medium, tolerance to 0.2% picrate in Sauton agar, and non-use of citrate as a sole carbon source are characteristics that distinguish M. abscessus from M. chelonae. M. abscessus and M. chelonae sequevar I share an identical sequence in the 54-510 region of 16S rRNA, though both species can be differentiated by their hsp65, ITS or rpoB gene sequences. Genetics A draft genome sequence