The mycoplasmas, previously called "pleuropneumonia-like organisms" (PPLO), were first known as etiologic agents of bovine pleuropneumonia. Several species are now recognized, including three that are agents of human infectious disease.
Mycoplasma pneumoniae is the causative organism of"primary atypical pneumonia." The term implies that the disease is unlike bacterial pneumonias and does not represent a secondary infection by an opportunistic invader, but has a single primary agent. Clinically, mycoplasmal pneumonia resembles an influenza-like illness.
Mycoplasma hominis may be found on healthy mucous membranes, but is also associated with some cases of postpartum fever, pyelonephritis, wound infection, and arthritis.
Ureaplasmas are strains of mycoplasma that produce very tiny colonies and were, for this reason, once called "T-mycoplasmas."They have been renamed in recognition of their unique possession of the enzyme urease. These mycoplasmas, like M. hominis, are normally found on mucosal surfaces, but have sometimes been associated with urogenital and neonatal infections and female infertility.
Mycoplasmas are extremely pleomorphic (varied in size and shape). They are very thin and plastic because they lack cell walls. For this reason, unlike other bacteria, they can
Was this article helpful?