Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Reproduction > Microbiology of the GU tract (incomplete) > Flashcards

Microbiology of the GU tract (incomplete) Flashcards

1
Q

List bacteria causing STI

A 
Chlamydia trachomatis (chlamydia)
Neisseria gonorrhoeae (gonorrhoea)
Mycoplasma genitalium
Treponema pallidum (syphilis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

List virus causing STI

A 
Herpes simplex (genital herpes)
Hepatitis and HIV (not covered in this lecture)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

List Parasites causing STI

A

Trichomonas vaginalis
Phthirus pubis (pubic lice or “crabs”)
Scabies (not covered in this lecture)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Reason for a specific bug causing a specific syndrome

A

Proclivity for one or more tissues

Predictable inflammatory response.
Sonococci that infect the male urethra generally produce an intense neutrophil response that leads to a purulent discharge and pain with urination

C. trachomatis:in the same tissue, more likely to produce a mild, watery discharge or no symptoms at all.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

If you are testing for one organism, should you test for other organisms as well?

A

YES.

Coinfections are common.

STI pathogens move together: gonorrhea and chlamydia cause urethritis; genital ulcers greatly increase the probability of HIV acquisition.

Pre-test probability matters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which bacterial species is most common in vaginal flora?

A

Lactobacillus spp. predominate and are protective

- e.g L.crispatusandL. jensenii

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Other organisms in vaginal flora

A

+/- Group B beta-haemolytic Streptococcus - need to be eradicated in pregnant patients
+/- Candida spp. (small numbers)
+/-Strep “viridans” group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Predisposing factors for candida infection

A

Recent antibiotic therapy
High oestrogen levels (pregnancy, certain types of contraceptives)
Poorly controlled diabetes
Immunocompromised patients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Description of candida

A

“cottage cheese”

“curdy”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Presentation of candida

A

intensely itchy white vaginal discharge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Diagnosis of candida

A

clinical

high vaginal swab for culture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Treatment of candida infection

A

Topical clotrimazole pessaryor cream, (available OTC)
Oral fluconazole
Non-albicans Candida species
More likely to be azole resistant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Presentation of candida infection in males

A

Spotty rash of candida balanitis

Less common

Not sexually transmitted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Pathogenesis of gonococcal infection

A

Incubation period of urethral infection in males - SHORT (2-5 days)

Attaches to host epithelial cells and is endocytosed into the cell to replicate within the host cell and are released into the subepithelial space

Typical urethral infections result in prominent inflammation release of toxic lipo-oligosaccharide and peptidoglycan fragments as well as the release of chemotactic factors that attract neutrophilic leukocytes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Gram stain features of gonorrhoea

A

Gram -ve intracellular diploccocus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Neisseria gonorrhoea infects which parts of the body?

A

urethra
rectum
throat & eyes
endocervix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Which is more common? Gonorrhoea or Chlamydia?

A

Chlamydia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Morphology of Neisseria gonorrhoea

A

gram negative diplococcus
Looks like 2 kidney beans facing each other
easily phagocytosed by polymorphs - intracellular appearance on gram film

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Other tests for N. Gonorrhoea

A

Microscopy of urethral/endocervical swabs
- Done in Sexual and Reproductive Health (SRH) clinic – 90+% specificity in males, less in females

Culture on selective agar plates

  • Selective agar suppresses growth of normal flora
  • Done on endocervical, rectal and throat swabs but NOT high vaginal swabs
  • Now only done on patients attending SRH clinic in Tayside
  • Swabs from GP patients were often falsely culture negative as organism would die during transit to lab
  • Non selective media used where no competing flora are expected (e.g. synovium)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Nucleic Acid Amplification Tests (NAATs)

A

increase in sensitivity over culture
ability to test urine specimens and self-obtained vaginal swabs,
Inability to perform antimicrobial susceptibility testing
Poor/ inadequately defined positive predictive value of some NAATs when they are used to test low-prevalence populations.
Where the prevalence of N. gonorrhoeae is now well below 1%, the risk of false-positive screening results may be high, and reliable results depend on the use of assays with exquisite specificity.
Will detect dead organisms (have to wait 5 weeks to do “test of cure” tests)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Features of chlamydia trachomatis

A

Gram non-staining but behaves as gram -ve.

Most common bacterial STI

Obligate intracellular bacteria with biphasic life cycle - “energy parasite”

Does not reproduce outside host cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Which areas does Chlamydia trachomatis infect?

A

urethra
rectum
throat and eyes
endocervix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Treatment of chlamydia

A

Azithomycin (1g oral dose) for uncomplicated chlamidia

Doxycycline 100mg bd x 7 days - this is what is currently stated in guidelines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Which serovars (serological subgrouping) of chlamydia trachomatis causes gential infection?

A

D-K

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Which serological grouping of Chlamydia Trachomatis is identical to Crohn’s disease?

A

Serovars L1 to L3

Lymphogranuloma Venerum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What treatmet options are available to patients who cannot tolerate azithromycin or doxacyline with chlamydia?

A

erythromycin

ofloxacin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Diagnosing chlamydia and gonorrhoea

A

combined NAAT or PCR - tests for both organism in 1 test.

Men: first pas urine sample (not midstream)

Female: HVS or vulvo-vaginal swab (VVS) which can be either self taken or endocervical swab which is clinician taken

Rectal and throat swabs

Eye swabs (babies and adults)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Features of Trichomonas Vaginalis

A

Single celled protozoal parasite
divides by binary fission (no cyst form is known) – human host only

Transmitted by sexual contact

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Clinical features of Trichomonas vaginalis

A

vaginal discharge and irritation in females

Urethritis in males

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How to diagnose T. vaginalis

A

High vaginal swab

No good test for males

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Treatment of T. vaginalis

A

Oral metronidazole

32
Q

Describe the discharge of bacterial vaginosis

A

homegenous
may contain bubbles
Fishy odour

33
Q

Microscopy of bacterial vaginosis

A

Adding 10% potassium hydroxide to the discharge on the slide elicits an amine-like, fishy odor, yielding a positive “whiff” test (amines from the anaerobic flora.
A wet mount reveals the absence of bacilli and their replacement with clumps of coccobacilli. Some vaginal epithelial cells are coated with coccobacilli, which may obscure their edges (clue cells) or the normally clear appearance of the cytoplasm. Relatively few polymorphonuclear leukocytes are observed

34
Q

What is the significance of large numbers of leukocytes in wet mount of BV?

A

Coincident infection

possibly trichomoniasis or bacterial cervicitis

35
Q

Consequences of bacterial vaginosis

A

Increased rate of upper tract infection (endometritis, salpingitis)

premature rupture of the membranes and preterm delivery ( treatment of asymptomatic women with BV who are not at high risk for preterm delivery appears to confer no benefit.)

Women with BV may have increased risk for the acquisition of HIV

36
Q

4 stages of syphilis infection (incomplete)

A
  1. Primary lesion
  2. Secondary stage
  3. Latent stage
  4. Late stage
37
Q

What is primary lesion stage of syphilis?

A 
Chancre - painless 
Organisms multiply at inoculation site and gets into bloodstream
Extra-genital sites of lesion - 10%
Non tender focal lymphadenopathy
Heals without treatment
38
Q

What is secondary stage of syphilis?

A

Incubation - 6 weeks to 6 months

Large no. of bacteria circulating in the blood

Multiple manifestations at different sites

  • “snail track” mouth ulcers
  • generalised rash - macular, follicular or pustular rash on palms + soles
  • flu-like symptoms
  • Lesions of mucous membranes
  • Generalised Lymphadenopathy
  • Patchy Alopecia
  • Condylomata Lata (most highly infectious lesion in syphilis, exudes a serum teeming with treponemes
39
Q

What is the latent stage of syphilis

A

No symptoms
low level multiplication of spirochete in the intima of small blood vessels
Some patients will self cure or be treated co-incidentally

40
Q

What is late stage syphilis

A

Cardiovascular or neurovascular complications many years later

41
Q

What are the symptoms of mycoplasma genitalium carriage?

A

Asymptomatic carriage

42
Q

List the associated conditions of mycoplasma genitalium

A

Non gonoccocal urethritis

PID

43
Q

Presentation of gonorrhea in males

A

Asymptomatic - <10%
Urethral discharge - >80%
Dysuria
Pharyngeal/rectal infections - mostly asymptomatic

44
Q

What should be done to manage males having unprotected anal sex?

A

Offer pre-exposure prophylaxis

45
Q

Presentations of gonorrhoea in females

A

Asymptomatic (up to 50%)
Increased/altered vaginal discharge (40%)
Dysuria
Pelvic pain (<5%)
Pharyngeal and rectal infection are usually asymptomatic

46
Q

Upper genital tract complications of gonorrhoea

A 
Endometritis
PID
Hydrosalpinx
Infertility
Ectopic pregnancy
Prostatitis
47
Q

Lower genital tract complications of gonorrhoea

A 
Bartholinitis - inflammation of bartholin gland 
Tysonitis
Periurethral abscess
Rectal abscess
Epididymitis
Urethral stricture
48
Q

Diagnosing Gonorrhoea

A

NAATs (screening test) >96% sensitivity

Microscopy (Symptomatic)

  • Urethral 90-95% sensitivity
  • Endocervical 37-50% sensitivity

Culture (if Micro +ve or contact of GC)

  • Urethral >95% sensitivity
  • Endocervical 80-92% sensitivity
49
Q

Treatment of gonorrhoea

A

First-line: Ceftriaxone 500 mg IM
Second-line: Cefixime 400 mg oral (only if IM injection is contra-indicated or refused by patient)
Test of cure in all patients after 2 weeks

50
Q

Presentation of primary infection of genital herpes

A 
Blistering and ulceration of the external genitalia
Pain
External dysuria
Vaginal or urethral discharge
Local lymphadenopathy
Fever and myalgia (prodrome)
51
Q

What is the incubation period of HSV primary infection?

A

3-6 days

52
Q

What is the duration of genital herpes primary infection

A

14-21 days

53
Q

Features of reccurent episodes of HSV

A

More common with HSV-2

often overlooked/misdiagnosed

usually unilateral, small blisters and ulcers

minimal systemic symptoms, resolves within 5-7 days

54
Q

Investigation and management of genital herpes

A

Swab base of ulcer (viral medium) for HSV PCR
Give oral antiviral Treatment (Aciclovir 400mg TDS x 5/7)
Consider topical Lidocaine 5% ointment if very painful
Saline bathing
Analgesia

55
Q

Are HSV-1 attacks more frequent than HSV-2?

A

YES

56
Q

When is viral shedding seen most commonly?

A

More frequent in the first year of infection

More in individuals with frequent recurrences

57
Q

How do you reduce/manage viral shedding (HSV)?

A

Acicolvir 700mg BD for 12 months

58
Q

Special circumstances to take caution with HSV

A

PREGNANCY

  • previous herpes episode means antibodies can be passed to the baby
  • First episode in 3rd trimester (within 6 weeks of EDD)
  • ? Primary or non-primary
  • Inform O+G (review birth plan)
59
Q

Which HPV genotypes are covered by quadrivalent vaccines?

A

6, 11, 16, 18

60
Q

Which HPV genotypes are covered by nanovalent vaccine?

A

31, 33, 45, 52, 58

61
Q

Symptoms of HPV vary with gentoype - t or f

A

TRUE

62
Q

Clinical sequelae of HPV

A

latent infection
anogenital warts
palmar and plantar warts
cellular dysplasia/intraepithelial neoplasia

63
Q

How is HPV transmitted?

A

Likely to have acquired HPV from asymptomatic partner
Incubation period – 3 weeks to 9 months (3mth)
Subclinical disease is common on all anogenital sites
Transmission of more than one HPV type is common

64
Q

What to do when patient presents with genital warts?

A

Cervical screening

65
Q

Location of anogenital warts of HPV

A

perianally
sub prepucal
anywhere in the anogenital region
sites of friction

66
Q

Description of warts in HPV

A

cauliflower lesion

67
Q

HPV treatment

A

Podophyllotoxin (Warticon)
Cytotoxic
Not licensed for extra genital warts (but widely used)

Imiquimod (Aldara)
immune modifier
can be used on all Anogenital warts

Cryotherapy
Done in combination with the above
Cytolytic can require repeat sessions at 2 week intervals

Electrocautery

68
Q

HPV vaccination indication

A

Vaccinate both men and women

vaccine is given to MSM men, as those having sex with women would be protected if the woman is vaccinated

69
Q

Is the HPV vaccination successful in reducing cervical cancer?

A

YES

79% reduction in CIN 1
88% reduction in CIN 2
89% reduction in CIN 3

70
Q

How is treponema pallidum transmitted?

A

Sexual contact
Trans-placental/during birth
Blood transfusions
Non-sexual contact – healthcare workers

71
Q

How to classify acquired syphilis

A

EARLY INFECTIOUS

  • primary
  • secondary
  • early latent

LATE NON INFECTIOUS

  • Late latent
  • Tertiary
72
Q

Incubation period of primary syphylis

A

9-90 days (mean of 21 days)

73
Q

Diagnosis of syphilis

A 
Demonstration of Treponema Pallidum 
(from lesions or infected lymph nodes)
- Techniques  
     - Dark Field Microscopy
     - PCR (polymerase chain reaction)

Serological Testing
- Detects antibody to pathogenic treponemes

74
Q

Non treponemal serological tests for syphilis

A

VDRL (Venereal Disease Research Laboratory)

RPR (Rapid Plasma Reagin)

75
Q

Treponemal serological tests for syphilis

A

TPPA (Treponemal Pallidum Particle Agglutination)
ELISA/EIA (Enzyme Immunoassay) SCREENING TEST
INNO-LIA (Line immunoassay)
FTA abs (Fluorescent Treponemal Antibody absorbed)

Reproduction (32 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions