|Herpes Varicella-Zoster (Shingles) Infection
|Chickenpox Varicella Infection
|Varicella Cerebral Vasculopathy
|Herpes Zoster Ophthalmicus (HZO) Shingles
|Rubella (German Measles)
|Epstein-Barr Virus infection
| Cytomegalovirus (CMV) infections
| CMV retinitis infections
- These are small organisms that lack a cell wall but can replicate outside of the host cell but are difficult to culture
- They are the smallest free-living micro-organisms
- Most are harmless and only a minority are disease-producing.
- Usually non-invasive and just cause local mucosal damage or stimulate autoimmune responses in the host.
- May cause pneumonia, urethritis and pelvic inflammatory disease
- Mycoplasma pneumoniae : URTI - spread by coughs. Incubation period 2-3 weeks. Commonest in 5-20-year-olds. Bronchitis and pneumonia. Host produces IgM to 'I' antigen on red cells. Causes haemolysis. Direct Coombs positive. Overall not severe and rarely life-threatening. Bullous myringitis seen in the experimentally induced disease. Erythema multiforme, Stevens-Johnson syndrome. Raynaud's, Internal carotid artery occlusion and strokes, aseptic meningitis, transverse myelitis and GBS. Polyarthralgias.
- Mycoplasma hominis : vaginitis and PID is not sensitive to Erythromycin
- Mycoplasma genitalium : urethritis and PID
- ureaplasma urealyticum (hydrolyzes urea) : urethritis
- Mycoplasma fermentans : overwhelming infection in the immunocompromised
- Cold agglutinins clump erythrocytes at 4 C and dissociate if reheated to 37 C can be caused by Mycoplasma, EBV (anti-i), CMV (anti-I), viruses, lymphomas
- They do not respond to antibiotics that damage the cell wall (Penicillin and cephalosporin) as they don't have one. Use macrolides or tetracyclines. Avoid tetracyclines in pregnant and children. Erythromycin can cause Theophylline toxicity. Course of 7-14 days.