Sexually Transmitted Infections (STIs)

Question 1

What are 4 common characteristics of organisms that cause STIs?

Answer 1

• Initially negligible symptoms
• Persist & symptoms reoccur
• Lack of immunity
• Fastidious (sensitive to drying)

Question 2

What is PID (pelvic inflammatory disease)?

Answer 2

Extensive infection of cervix, uterus, fallopian tubes, and/or ovaries

Question 3

What are the symptoms of PID?

Answer 3

Lower abdominal pain, discharge from vagina

Question 4

What are 2 organisms that can cause PID?

Answer 4

• Chlamydia trachomatis (D-K)

- Neisseria gonorrhoeae

Question 5

____ ____ is the most common bacterial STD

Answer 5

Chlamydia trachomatis

Question 6

Describe the morphology of chlamydia trachomatis

Answer 6

G- type, obligate intracellular parasite (require ATP from host)

Question 7

What are the 2 forms of chlamydia trachomatis?

Answer 7

• Infections form (EB)

- Metabolically active form (RB)

Question 8

What are the 3 species of Chlamydia that infect humans?

Answer 8

• C. trachomatis
• C. psittaci
• C. pneumoniae

Question 9

Describe how chlamydia trachomatis enters host cells

Answer 9

EBs bind to host cell receptors in a chlamydia vacuole, chlamydia then replicate + lyse host cell

Question 10

How does chlamydia trachomatis cause damage?

Answer 10

Inflammation

Question 11

What are 2 sequelae that can arise from PID?

Answer 11

• Ectopic pregnancy

- Scarring of fallopian tubes

Question 12

What is LGV (lymphogranuloma venereum) caused by?

Answer 12

C. trachomatis (L-1,2,3)

Question 13

What is LGV characterized by?

Answer 13

Suppurative (pus) inguinal adenitis (lymph gland in groin)

Question 14

How is LGV diagnosed?

Answer 14

DNA probes and PCR

Question 15

How to treat LGV?

Answer 15

Tetracycline or macrolides

Question 16

What is gonorrhea (GC) caused by?

Answer 16

Neisseria gonorrhoeae

Question 17

Describe the morphology of Neisseria gonorrhoeae

Answer 17

G- aerobic diplococci, no capsule, twitching motility

Question 18

How is gonorrhea transmitted?

Answer 18

Direct contact

Question 19

What are the symptoms of gonorrhea in males?

Answer 19

Purulent urethral discharge and painful urination

Question 20

What are the 3 types of gonorrhea?

Answer 20

• Rectal gonorrhea
• Pharyngeal gonorrhea
• Disseminated gonococcal infection (DGI)

Question 21

What are the 4 virulence factors for gonorrhea?

Answer 21

• Adhesins and Invasins: Pili and Opa
• Lipooligosaccharide (LOS)
• IgA Protease

Question 22

Why is there no life long immunity for gonorrhea?

Answer 22

Antigenic and phase variation

Question 23

How is gonorrhea diagnose?

Answer 23

Cultures, DNA probes, PCR

Question 24

How is gonorrhea treated?

Answer 24

As if patient have all 3 bacterial STIs

- Penicillin was drug of choice

Question 25

Human papilloma virus is a ___________ ___ virus.

Answer 25

non-enveloped DNA.

Question 26

Which genotypes of HPV are associated with cervical & penile cancers?

Answer 26

Types 16 & 18.

Question 27

Warts of the genital tract are also called:

Answer 27

condylomata accuminata.

Question 28

HPV warts are usually removed by:

Answer 28

laser or podophyllin.

Question 29

Which types of HPV are covered in vaccines?

Answer 29

All cover 16 & 18. | One also covers 6 & 11 (warts) as well as 31, 32, 45, 52 & 58 (cancer).

Question 30

What is syphilis caused by?

Answer 30

Treponema pallidum

Question 31

Describe the morphology of treponema pallidum

Answer 31

G- type, spirochaete, can't be cultured in vitro

Question 32

What are the 3 stages of syphilis?

Answer 32

Primary, secondary, tertiary

Question 33

Which stage of syphilis is most infectious?

Answer 33

Primary

Question 34

What is the initial sign of syphilis?

Answer 34

Hard chancre

Question 35

What is the second stage of syphilis?

Answer 35

Infectious rash on skin and mucous membranes

Question 36

What is the portal of entry for syphilis?

Answer 36

Breaks in skin or mucous membranes

Question 37

What does treponema pallidum produce that helps it penetrate tissues?

Answer 37

Enzymes like hyaluronidase

Question 38

What are gummas which are formed in the tertiary stage of syphilis?

Answer 38

Thickened scar tissues due to chronic inflammation

Question 39

How is syphilis diagnosed?

Answer 39

Serology (antibodies to T> pallidum)

Question 40

What are 3 complications of syphilis?

Answer 40

Aortic aneurysm, CNS damage, congenital syphilis

Question 41

How is syphilis treated?

Answer 41

Penicillin

Question 42

What is haemophilus ducreyi?

Answer 42

G- aerobic rods that cause chancroid and soft chancres

Question 43

How is H. ducreyi treated?

Answer 43

Ceftriaxone

Question 44

What type of virus is HSV 1/2?

Answer 44

DNA, enveloped

Question 45

What are the 2 types of infection due to HSV 1/2?

Answer 45

Chronic and latent

Question 46

When is HSV 1/2 most infectious?

Answer 46

Primary lesions (vesicles) are apparent

Question 47

What are 2 complications of HSV 1/2?

Answer 47

- Encephalitis | - Disseminated herpes in fetus