Topic overview

Start with the big picture

Without a rigid cell wall, mycoplasmas are pleomorphic, are not visible on Gram stain, and are not susceptible to beta-lactam antibiotics. Their cholesterol-containing membranes require external sterols for growth on specialized media. Species can also be distinguished by colony appearance. Clinically, M. pneumoniae is associated with atypical respiratory illness, while M. hominis, M. genitalium, and Ureaplasma urealyticum are linked to different genitourinary, pregnancy-related, or neonatal syndromes. The deeper lesson organizes these organisms by their general features, species-specific presentations, laboratory diagnosis, treatment, and prevention. It also connects key mechanisms—such as epithelial adhesion and tissue injury—to clinical clues, while introducing diagnostic approaches including PCR and serology.