Exam 4: Sexually Transmitted Infections, Bacterial:

Question 1

sexually transmitted infections

Answer 1

chlamydia
gonorrhea
syphilis

Question 2

overview of STIs

Answer 2

STIs can be transmitted through any type of unprotected sexual contact
common bacterial STIs:
-chlamydia, gonorrhea, syphilis
-all are difficult to culture; require NAAT or serology testing
-often asymptomatic
common viral STIs: HPV, HSV2, HIV
common parasitic STIs: trichomoniasis

Question 3

Chlamydia: Chlamydia trachomatis

Answer 3

signs/symptoms:

• male: urethritis, dysuria, burning and itching of the penis, discharge
• female: dysuria, vaginal discharge, painful sexual intercourse, pelvic pain

Question 4

chlamydia: mechanism of disease

Answer 4

Infection: elementary body form of C. trachomatis infects host cells
Elementary body converts to a reticulate body
Replication: reticulate body replicates inside host cells
Reticulate bodies convert back to elementary bodies
Lysis: Elementary bodies lyse out of host cells

Question 5

Chlamydia trachomatis

Answer 5

Characteristics:
-Gram negative bacteria
-Obligate intracellular pathogen
-Difficult to culture in lab
Diseases: chlamydia
Transmission:
-Sexual contact
-Trachoma: hand to eye contact (fomites and flies also)
Virulence factors: 
-Intracellular lifecycle
Lab diagnosis: NAAT
Treatment: Antibiotics

Question 6

Gonorrhea: Neisseria gonorrhoeae

Answer 6

Etiological agent:
-Gram negative diplococcus
-fastidious
signs and symptoms:
-male: dysuria, discharge, increased risk infertility
-female: painful urination, increased vaginal discharge, increased risk infertility
drug-resistant Neisseria gonorrhoeae is on the CDC list of urgent threats

Question 7

Neisseria gonorrhoeae

Answer 7

characteristics:
-Gram-negative diplococcus
-highly fastidious
Diseases:
-gonorrhea
-PID
-neonatal gonorrhea
transmission:
-sexual contact
-vertical transmission at birth
virulence factors:
-adhesions
-biofilm formation
lab diagnosis: NAAT

Question 8

pelvic inflammatory disease

Answer 8

etiological agents: chlamydia and gonorrhea are the main causes of PID
complications: chronic pelvic pain, ectopic pregnancy, miscarriages and infertility in untreated cases
diagnosis:
-tenderness during a pelvic exam
-bloodwork
-biopsy, ultrasound, MRI, or laparoscopy

Question 9

diagnostic tests using afflutination

Answer 9

Treponema pallidum particle agglutination assay (TPPA) test;
-tests for syphilis
+ result=patient has antibodies against T. pallidum
- result= patient has no antibodies against T. pallidum

Question 10

syphilis: Treponema pallidum

Answer 10

Gram negative spirochete