Micro 33: Mycoplasma

This episode explores Mycoplasma, the smallest free-living bacteria and uniquely defined by the absence of a cell wall. Drawing from Murray’s Chapter 33, it examines how structural minimalism reshapes both pathogenesis and therapy.Without peptidoglycan, Mycoplasma species are intrinsically resistant to beta-lactam antibiotics and exhibit pleomorphic morphology. Their sterol-rich cell membranes provide flexibility and resilience, allowing close adherence to respiratory and urogenital epithelium.The primary clinical focus is Mycoplasma pneumoniae, a common cause of atypical pneumonia. Rather than producing lobar consolidation, it induces a more diffuse interstitial process, often accompanied by extrapulmonary manifestations driven by immune response rather than direct invasion.The episode emphasises three conceptual themes:* Absence of cell wall alters staining and antibiotic susceptibility* Disease is often immune-mediated* Laboratory diagnosis relies on molecular or serologic methods rather than traditional cultureClinically, Mycoplasma teaches restraint: mild radiographic findings may accompany significant symptoms, and macrolides or tetracyclines are required for treatment.Key Takeaways* Mycoplasma lacks a cell wall* Beta-lactam antibiotics are ineffective* M. pneumoniae causes atypical pneumonia* Immune-mediated symptoms may accompany infection* Diagnosis often relies on molecular or serologic testing This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit drmanaankarray.substack.com/subscribe