TY - CHAP M1 - Book, Section TI - Mycoplasma A1 - Ryan, Kenneth J. Y1 - 2022 N1 - T2 - Sherris & Ryan's Medical Microbiology, 8th Edition AB - OverviewMycoplasma are tiny bacteria that lack a cell wall. Their outer cell membrane contains sterols that they obtain from the tissues in which they grow. Mycoplasma pneumoniae is second only to the pneumococcus as a cause of community-acquired pneumonia. However, M pneumoniae has a predilection for younger persons and spreads person-to-person in families or closed groups, whereas the elderly are at greatest risk for pneumococcal pneumonia. Mycoplasmal infection presents as tracheobronchitis or pneumonia with headache and a persistent nonproductive cough, often worse at night. Chest radiographs usually show unilateral patchy infiltrates without lobar consolidation, hence the term atypical pneumonia. The course is almost always benign, but improvement is accelerated by treatment with doxycycline or azithromycin. In the past, diagnosis was confirmed if at all by serology or rarely by culture. Multiplex PCR platforms for respiratory pathogens and pneumonia have changed the approach to diagnosis.There has been a resurgence interest and research in Mycoplasma genitalium (MG ), which is second only to Chlamydia trachomatis as a cause of cervicitis, urethritis, and pelvic inflammatory disease (PID). The recognition of MG as a major cause of sexually transmitted infection (STI) has been transformed by NAA testing, since it does not grow in culture. Gene variations that result in resistance to macrolides and fluoroquinolones are an emerging problem globally.Mycoplasma hominis is a resident of the genitourinary tract; however, its clinical manifestations are uncommon and extragenital. It can cause transient bacteremia with parturition, localized infection in joints, including prosthetic ones, and sternal wound infections after cardiac surgery. M hominis can be grown on chocolate agar from tissue or aspirated fluid obtained sterilely from these sites. Confirmed infections are treated with doxycycline or a fluoroquinolone; they are resistant to macrolides and β-lactams.The role of Ureaplasma in human disease syndromes remains ill-defined. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - accessmedicine.mhmedical.com/content.aspx?aid=1185634074 ER -