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21 Cards in this Set
- Front
- Back
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Mycoplasma and Ureaplasma - General
Species |
Lack cell wall, fastidious growth requirements
Commensals and pathogens; can have respiratory or genital infections M. pneumoniae, hominis, genitalium U. urealyticum |
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Chlamydia - General
Species |
Obligate intracellular bacteria, biphasic life-style
C. trachomatis, psittaci, pneumoniae |
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Mycoplasma and Ureaplasma - Pathogenesis
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affinity for respiratory/urogenital epithelium
decrease ciliary action desquamation/loss of ciliary action --> disease manifestation |
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Mycoplasma and Ureaplasma - Diagonsis
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Lack cell wall (cannot see w/ gram stain)
Slow, fastidious (require sterols) growth Unusual appearance on agar - fried egg colonies; M pneumoniae - spherical colonies |
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M. pneumoniae - epidemiology
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Highest rate - 5-20 yr olds; spread by aerosolized droplets
Single cases or mini epidemics Particular risk - Sickle cell 2-3 week incubation |
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M. pneumoniae - pathogenesis
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Adhere to epithelial lining; anti-ciliary action
Immunopathogenesis - activate host immune response Produce toxic products (H2O2) Exfoliation, inflammation |
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M. pneumoniae - clinical features
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Tracheobronchitis, pneumoniae (atypical - culture/gram stain/beta-lactam antibiotic - negative)
Mild symptoms - walking pneumonia Gradual onset, prolonged symptoms, dry hacking cough, bilateral chest x-ray infiltrate Bullous myringitis (rare) Clinical symptoms worse than pulm. exam |
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M. pneumoniae - extrapulmonary involvement
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Dermatologic - Stevens Johnson syndrome
Cardiac, Raynaud's, Neurologic |
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M. pneumoniae - diagnosis
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Sputum - culture
Serologic - complement-fixing Ab Cold agglutinins (early - time of presentation) |
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Genital mycoplasmas - general, transmission, species
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Lack cell wall, opportunists, normal flora in UG tract
STD (genitalia contact), vertical M. hominis (pyelonephritis, PID, salpingitis) U. urealyticum (urethritis) M. genitalium (urethritis, PID) |
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Genital mycoplasmas - clinical presentation
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Limited to GU tract; urethritis (non-GC --> symptoms persist w/ GC therapy);
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Genital mycoplasmas - diagnosis
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Special media, days-weeks, fried egg colonies
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Chlamydia - general
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Gram (-), obligate intracellular (unique life cycle)
Bind columnar epithelial cells |
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Chlamydia - pathogenesis
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Elementary bodies - resistant extracellular infectious form
Reticulate bodies - non-infectious intracellular form (fragile) |
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C. trachomatis -epidemiology
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Ocular infection; worldwide
Transmission - droplet, person-person, contaminated clothing, flies, vertical Genital infection - urethritis, cervicitis Lymphogranuloma venerum (LGV) - Africa/Asia, S. America - in US - reservoir = MSM |
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C. trachomatis - pathogenesis
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Infects non-ciliated columnar epithelial cells
No long-lasting immunity - reinfection common Post-infectious complications |
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C. trachomatis - clinical presentation
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Trachoma (eye infection) - first infection <2 y/o (endemic areas); repeated infection = inflammation/scarring; blindness
Neonatal conjuctivitis (5-12 days postpartum) Infant pneuomonitis (4-11 weeks postpartum) Genital infection - commonly asymptomatic (75%M, 80%W); urethritis, proctitis; women - PID Non-GC urethritis - dysuria, discharge Post-GC urethritis - dual infection with N. gonorrhoeae - 50%; can have symptoms after GC therapy Reactive arthritis (immune-mediated) Lympgranuloma venereum (LGV) Systemic symptoms (fever, malaise, headache, myalgia); progresses to lymph nodes (unilateral, enlarged painful) - groove sign (ing. ligament), rupture,drain |
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C. trachomatis - diagnosis
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Swab - nucleic acid amplification
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C. trachomatis - treatment
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Screen
Trachoma - Surgery, Antibiotics, Face washing, Environmental control |
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C. psitacci
causes psittacosis |
Natural reservoir = birds; transmission - exposure to feathers, feces
Incubation = 7-14 days |
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C. pneumoniae
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Another cause of atypical pneuonia
Young adults, person-person transmission Clinical presentation similar to M. pneumoniae - often asymptomatic |
