Mycoplasma/Chlamydia

Question 1

mycoplasma, ureaplasma, and chlamydia sp - overview

Answer 1

*smallest free-living bacteria
*NO CELL WALL (resistant to antibiotics that target the cell wall)
*cell membrane contains STEROLS
*coccobacilli

Question 2

mycoplasma pneumoniae - morphology

Answer 2

*EXTRACELLULAR pathogen

Question 3

mycoplasma pneumoniae - virulence factor

Answer 3

*P1 adhesin!
*causes ciliostasis, causing persistent cough
*functions as a SUPERANTIGEN
*also can change surface lipoproteins to evade host defense

Question 4

mycoplasma pneumoniae - clinical presentation

Answer 4

*occurs in 6-8 year cycles
*pathogenic upon colonization (not part of normal flora)
*causes walking (atypical) pneumonia
*initial fever with prolonged coughing
*complications include MYRINGITIS (blisters on tympanic membrane), encephalitis, hemolytic anemia

Question 5

genital mycoplasmas

Answer 5

*include M. hominis, M. genitalium, and ureaplasma species
*colonization increases as sexual activity increases
*M. genitalium can cause nongonococcal urethritis, cervicitis, and pelvic inflammatory disease

Question 6

mycoplasma diagnosis

Answer 6

*NAAT (of urine - for genital strains)
*respiratory PCR panel (for M. pneumoniae)

Question 7

mycoplasma treatment

Answer 7

macrolides, tetracycline, or fluoroquinolone
*can NOT use antibiotics that target the cell wall

Question 8

chlamydia sp

Answer 8

*obligate INTRACELLULAR pathogens
*gram negative
*LPS with weak endotoxin activity
*MOMP and OMP2 are important proteins that we develop antibodies against

Question 9

chlamydia - virulence factors

Answer 9

*weak LPS (endotoxin)
*outer membrane protein (MOMP) - defines serovars
*OMP2

Question 10

chlamydia life cycle

Answer 10

1. attach to host cell
2. ingestion into the cell
3. reorganization #1
4. growth by binary fission
5. reorganization #2 - into ELEMENTARY BODIES (infectious) - released from cell
6. RETICULATE BODIES (non-infectious, metabolically active)

Question 11

elementary bodies (EBs) - chlamydia

Answer 11

metabolically inactive, INFECTIOUS forms of chlamydia

Question 12

reticulate bodies (RBs) - chlaymdia

Answer 12

metabolically ACTIVE, noninfectious forms of chlamydia

Question 13

chlamydophila pneumoniae

Answer 13

*sinusitis, pharyngitis, bronchitis, and pneumonia
*transmitted via respiratory secretions
*causes atypical pneumonia (like mycoplasma pneumoniae)
*association with atherosclerosis?

Question 14

presentations of chlamydia trachomatis

Answer 14

-trachoma
-adult inclusion conjunctivitis
-neonatal conjunctivitis
-infant pneumonia
-urogenital infections
-lymphogranuloma venereum

Question 15

trachoma (a clinical presentation of chlamydia trachomatis)

Answer 15

chronic inflammatory granulomatous process of eye surface, leading to corneal ulceration, scarring, pannus formation, and blindness
*endemic in Africa, Middle East, South Asia, and South America

Question 16

adult inclusion conjunctivitis (a clinical presentation of chlamydia trachomatis)

Answer 16

acute process with mucopurulent discharge, dermatitis, corneal infiltrates, and corneal vascularization in chronic disease

Question 17

neonatal conjunctivitis (a clinical presentation of chlamydia trachomatis)

Answer 17

acute process characterized by mucopurulent discharge

Question 18

infant pneumonia (a clinical presentation of chlamydia trachomatis)

Answer 18

after a 2-to-3 week incubation period, the infant develops rhinitis, followed by bronchitis with a characteristic dry cough

Question 19

urogenital infections (a clinical presentation of chlamydia trachomatis)

Answer 19

acute process involving the genitourinary tract with characteristic mucopurulent discharge, asymptomatic infections common in women
*often cervicitis, urethritis (NGU), etc

Question 20

lymphogranuloma venereum (a clinical presentation of chlamydia trachomatis)

Answer 20

a painless ulcer develops at the site of infection that spontaneously heals, followed by inflammation and swelling of lymph nodes draining the area, then progression to systemic symptoms

Question 21

chlamydia - STD ranking

Answer 21

1 STD in the US

Question 22

diagnosis of chlamydia

Answer 22

NAAT - looking for chlamydia, gonorrhea, and genital mycoplasma at the same time