B1-2 Microbiology Std & Vaginal Discharge

Front 1

What agent causes this STD:
Chalmydial Infection?

Back 1

Chlamydia trachomatis

Gram (-) but has no peptidolycan layer or muramic acid

Front 2

What agent causes this STD: Gonorrhea?

Back 2

Neisseria gonorrhoeae

Gram (-) diploccoci

Front 3

What agent causes this STD: Genital herpes?

Back 3

Herpes simplex virus (HSV) type II and type I

Envelope, double stranded (DS) linear DNA

Front 4

What agent causes this STD: Warts, anogenital cancer?

Back 4

Human Papillomarirus (HPV)

Naked envelope, DS circular DNA

Front 5

What agent causes this STD: Trichomoniasis?

Back 5

Trichomonas vaginalis

Protozoan (parasite)

Front 6

What agent causes this STD: AIDS?

Back 6

Human immunodeficiency virus (HIV)

Retrovirus, spherical enveloped virion with a central cylindrical nucleocapsid

Front 7

What agent causes this STD: Chancriod (genital ulcer)?

Back 7

Haemophilus ducreyi

Gram (-) coccobacilli

Front 8

What agent causes this STD: Syphillis?

Back 8

Treponema pallidum

Gram (-) spirochete

Front 9

What agent causes this STD: Lymphogranuloma venereum (LGV)?

Back 9

Chlamydia trachomatis (L biovars - another variant)

Gram (-) pleomorphic (because it doesn't have a peptidoglycan or muramic acid

Front 10

What agent causes this STD: Granuloma inguinale?

Back 10

Donovania granulomatis/Klebsiella granulomatis

Front 11

What agent causes this STD: Candidiasis?

Back 11

Candida albicans

fungus

Front 12

What agent causes this STD: bacterial vaginosis?

Back 12

Gardnerella vaginalis

gram (-) rod

Front 13

What agent causes this STD: pubic lice (crab lice)?

Back 13

Pthirus pubis

parasitic insect

Front 14

What agent causes this STD: scrabies?

Back 14

Sarcoptes scabiei

a mite

Front 15

What STD (& their agent) produce external genital ulcer without vaginal discharge?

Back 15

1. Syphilis (Treponema pallidum)
2. Chanchroid (Haemophilus ducreyi
3. Granuloma inguinale (klebsiella granulomatis)
4. Herpes (HSV)

Front 16

What are the general structural features of Treponema pallidum?

Back 16

Treponema pallidum is a spirochete causing syphilis.

Features:
1. Spirochete
2. Sensitive to drying, disinfectant, heat and PCN

Front 17

What are the virulence factors of treponema pallidum?

Back 17

Virulence:
1. Outer membrane proteins; promote adherence
2. Hyaloronidase: facilitates pervascular infiltration
3. Fibronectin: anti-phagocytosis

Front 18

How do you diagnose syphilis?

Back 18

1. VDRL: venereal disease reference laboratory test
2. DFA: darkfield or direct flourescent antibody microscopy in primary or secondary stages of syphilis
3. Serology in secondary and late phases of syphilis

Front 19

What are the 3 stages of syphilis pathogenesis?

Back 19

1. Primary: (10-90days) organism is localized to a chancre or skin lesion; ulcer "heals" spontaneously within 2mons
2. Secondary: flu-like syndrome followed by disseminated skin rash which all will resolve spontaneously within few weeks
3. Tertiary: approx 1/3 of untreated patients; the immune response leads to the destruction of any tissue; granulomatous lesion (gummas) may be found in bone, skin, & other tissues

Front 20

What family and genus does H. ducreyi and general physiological properties?

Back 20

Family in Pasteurellaceae (has been reclassified)

Gram (-) rod (sometimes pleomorphic)
Non-spore forming, aerobes or falcultive aneaerobes

Front 21

What is the difference between the genital lesions of syphilis and chancroid?

Back 21

Chancroid lesions are usually not indurated

Syphilis chancre is nontender and indurated

Front 22

What are the basic physiologic propertiy of K. granulomatis?

Back 22

Gram (-) bacillus

prominent capsule
mucoid appearance of colonies
enhanced virulence

Front 23

How is Klebsiella granulomatis transmitted and what does it cause?

Back 23

Transmitted through fecal route

causing STD-granuloma inguinale

Front 24

What does Sarcoptes scrabiei cause and its life cycle?

Back 24

This causes scabies through prolonged skin to skin contact and is human specific

Life Cycle:
1. Female lays eggs as their burrow
2. Egg hatches and release larbae
3. larvae molt into nymphs
4. Males can mate with females...and the cycle continues

Front 25

What do Phthirus pubis cause and its life cycle?

Back 25

Causes public lice infestations (pthiriasis) usually spread through sexual contact (rarely thru clothing and bedding)

Life Cycle:
1. female lays eggs (nits) on hair shaft
2. Adults are found only on human host and cannot live 24-48h without blood