Illustration of Mycoplasma genitalium bacteria, also known as Mgen. This bacteria lives on the skin cells in the genital and urinary tracts in humans and can cause inflammation of these areas. Infection with Mycoplasma genitalium in humans can cause symptoms similar to chlamydia and gonorrhoea. Mycoplasma genitalium is the smallest self replicating organism known and is difficult to isolate and culture. Identification is therefore performed using a nucleic acid amplification test (NAAT).