Contact Bacteria Flashcards
CA - trachoma
Chlamydia trachomatis (strain)
- gram negative, coccobacillus; obligate intracellular parasite
Non STD
VF - trachoma
(Complex “life cycle” of C. Trachomatis)
Consists of 2 morphological distinct forms:
- elementary bodies
- reticulate bodies
Reticulate bodies - VF - trachoma
- Non-infectious form
- intracellular
- replicate
Elementary bodies - VF - trachoma
- infectious form
- invade epithelial cell
Reservoir - trachoma
Human
Transmission - trachoma
Direct - hand-to-eye contact with eye discharge
Indirect - sharing objects, towels
Arthropod - sandflies carrying eye discharge
Sxs - trachoma
Inflammation of upper eyelid (conjunctivitis) —> scarring/contraction of conjunctiva —> eyelashes turn inward —> eyelashes scratch cornea —> corneal cloudiness —> permanent blindness
Diagnosis - trachoma
Usually clinical/sxs ; vision changes
Pre-disposing factors - trachoma
Unsanitary conditions, over crowding, children
Prevention - trachoma
Washing hands, vector control of sand flies
- no vaccines
Treatments - trachoma
Antibiotics & surgery
Misc - trachoma
- Portal of entry - mucousa membranes (conjunctiva)
- Leading preventable cause of blindness worldwide
- most cases occurs in Africa
CA - gonorrhea
Neisseria gonorrhoeae
- gram negative bacterium, diplococcus “coffee bean”
An STD
VF - gonorrhea
Capsule, fimbriae, opa proteins in cell wall: binds to T cell receptors —> inhibit immune response
(Used for attachment)
Reservoir - gonorrhea
Human
Transmission - gonorrhea
Spread by sexual contact
Sxs - gonorrhea
- Urethritis = Gonococcal Urethritis (painful when you pee)
Men - symptomatic - painful urination and yellow discharge; epididymitis (where sperm is stored)
Women - asymptomatic - fewer sxs; pelvic inflammatory disease (PID) (ovaries & falopian tubes)
If left untreated what happens? - gonorrhea
May become systemic if left untreated: endocarditis, meningitis, arthritis
Ophthalmia Neonatorum (neonatal conjunctivitis) - gonorrhea
Infant blindness due to a gonorrhea or genital chlamydial infections of the eyes during vaginal birth
Diagnosis - gonorrhea
Urine test or oral/urethral/rectal swab
- PCR - isolate & amplify DNA
- culture - look for gonococci on slide prep
Prevention - gonorrhea
Education & safe sex practices
Treatment - gonorrhea
Antibiotics
- injection
- oral medication
Misc - gonorrhea
-highest rates of infection - teenagers & young adults
- con infection with genital chlamydia !!
CA - genital chlamydia
AKA chlamydia
Chlamydia trachomatis
- gram negative, coccobacillus, obligate intracellular parasite
VF - genital chlamydia
Consists of 2 morphological distinct forms (complex lifecycles)
- elementary bodies
- reticulate bodies
Reservoir - genital chlamydia
Human
Transmission - genital chlamydia
Spread by sexual contact through epithelial mucosa
Sxs - genital chlamydia
Urethritis - non-gonococcal urethritis (NGU)
- men - symptomatic - painful urination & clear/watery discharge
- women - mostly asymptomatic; pelvic inflammatory disease (PID)
Diagnosis - genital chlamydia
NAATs (nucleic acid amplification tests)
- most sensitive tests available
- PCR is a type of NAAT
- performed on vaginal/urethral swabs or urine
Prevention - genital chlamydia
Education & safe sex practice
Treatment - genital chlamydia
Antibiotics
May also cause… - genital chlamydia
ophthalmia Neonatorum
Coinfection w what other disease? - genital chlamydia
Gonorrhea
What is the most common bacterial STD in US?
Genital chlamydia
CA - syphilis
Treponema pallidum
- gram negative, spirochete, motile
VF - syphilis
- lipid outer layer —> weak immune response
(Immune system less likely to respond to treponema)
Reservoir - syphilis
Human
Transmission - syphilis
Spread by sexual contact
Sxs - syphilis
Multiple disease stages
1. Primary phase
- chancre at site of infection
- develops 3 weeks after exposure
- highly infectious
- disappears after 2 weeks
2. Secondary phase
- skin & mucosal rashes on soles and palms
- can lead to latent period
3. Tertiary phase
- appears decades after latency
- formation of gummas (soft, tumor like lesions) on organs: bone, brain, heart & skin
- arthritis
- cardiovascular damage —> cardiovascular syphilis
- neurological damage, dementia —> neurosyphilis
Diagnosis - syphilis
Serology
1. Direct diagnosis - looking for T. Pallidum
2. Indirect diagnosis - looking for antibodies (IgM)
Prevention - syphilis
Education & safe sex practices
Treatment - syphilis
Antibiotics (only effective in early stages)
Misc - syphilis
Congenital syphilis - development damage to fetus & stillbirths
