Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

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

Microbiology of the GU tract (incomplete) Flashcards

(75 cards)

Start Studying
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
Which serological grouping of Chlamydia Trachomatis is identical to Crohn's disease?
Serovars L1 to L3 Lymphogranuloma Venerum
26
What treatmet options are available to patients who cannot tolerate azithromycin or doxacyline with chlamydia?
erythromycin | ofloxacin
27
Diagnosing chlamydia and gonorrhoea
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)
28
Features of Trichomonas Vaginalis
Single celled protozoal parasite divides by binary fission (no cyst form is known) – human host only Transmitted by sexual contact
29
Clinical features of Trichomonas vaginalis
vaginal discharge and irritation in females Urethritis in males
30
How to diagnose T. vaginalis
High vaginal swab | No good test for males
31
Treatment of T. vaginalis
Oral metronidazole
32
Describe the discharge of bacterial vaginosis
homegenous may contain bubbles Fishy odour
33
Microscopy of bacterial vaginosis
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
What is the significance of large numbers of leukocytes in wet mount of BV?
Coincident infection | possibly trichomoniasis or bacterial cervicitis
35
Consequences of bacterial vaginosis
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
4 stages of syphilis infection (incomplete)
1. Primary lesion 2. Secondary stage 3. Latent stage 4. Late stage
37
What is primary lesion stage of syphilis?
``` 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
What is secondary stage of syphilis?
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
What is the latent stage of syphilis
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
What is late stage syphilis
Cardiovascular or neurovascular complications many years later
41
What are the symptoms of mycoplasma genitalium carriage?
Asymptomatic carriage
42
List the associated conditions of mycoplasma genitalium
Non gonoccocal urethritis | PID
43
Presentation of gonorrhea in males
Asymptomatic - <10% Urethral discharge - >80% Dysuria Pharyngeal/rectal infections - mostly asymptomatic
44
What should be done to manage males having unprotected anal sex?
Offer pre-exposure prophylaxis
45
Presentations of gonorrhoea in females
Asymptomatic (up to 50%) Increased/altered vaginal discharge (40%) Dysuria Pelvic pain (<5%) Pharyngeal and rectal infection are usually asymptomatic
46
Upper genital tract complications of gonorrhoea
``` Endometritis PID Hydrosalpinx Infertility Ectopic pregnancy Prostatitis ```
47
Lower genital tract complications of gonorrhoea
``` Bartholinitis - inflammation of bartholin gland Tysonitis Periurethral abscess Rectal abscess Epididymitis Urethral stricture ```
48
Diagnosing Gonorrhoea
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
Treatment of gonorrhoea
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
Presentation of primary infection of genital herpes
``` Blistering and ulceration of the external genitalia Pain External dysuria Vaginal or urethral discharge Local lymphadenopathy Fever and myalgia (prodrome) ```
51
What is the incubation period of HSV primary infection?
3-6 days
52
What is the duration of genital herpes primary infection
14-21 days
53
Features of reccurent episodes of HSV
More common with HSV-2 often overlooked/misdiagnosed usually unilateral, small blisters and ulcers minimal systemic symptoms, resolves within 5-7 days
54
Investigation and management of genital herpes
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
Are HSV-1 attacks more frequent than HSV-2?
YES
56
When is viral shedding seen most commonly?
More frequent in the first year of infection | More in individuals with frequent recurrences
57
How do you reduce/manage viral shedding (HSV)?
Acicolvir 700mg BD for 12 months
58
Special circumstances to take caution with HSV
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
Which HPV genotypes are covered by quadrivalent vaccines?
6, 11, 16, 18
60
Which HPV genotypes are covered by nanovalent vaccine?
31, 33, 45, 52, 58
61
Symptoms of HPV vary with gentoype - t or f
TRUE
62
Clinical sequelae of HPV
latent infection anogenital warts palmar and plantar warts cellular dysplasia/intraepithelial neoplasia
63
How is HPV transmitted?
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
What to do when patient presents with genital warts?
Cervical screening
65
Location of anogenital warts of HPV
perianally sub prepucal anywhere in the anogenital region sites of friction
66
Description of warts in HPV
cauliflower lesion
67
HPV treatment
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
HPV vaccination indication
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
Is the HPV vaccination successful in reducing cervical cancer?
YES 79% reduction in CIN 1 88% reduction in CIN 2 89% reduction in CIN 3
70
How is treponema pallidum transmitted?
Sexual contact Trans-placental/during birth Blood transfusions Non-sexual contact – healthcare workers
71
How to classify acquired syphilis
EARLY INFECTIOUS - primary - secondary - early latent LATE NON INFECTIOUS - Late latent - Tertiary
72
Incubation period of primary syphylis
9-90 days (mean of 21 days)
73
Diagnosis of syphilis
``` 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
Non treponemal serological tests for syphilis
VDRL (Venereal Disease Research Laboratory) | RPR (Rapid Plasma Reagin)
75
Treponemal serological tests for syphilis
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.
© 2025 Bold Learning Solutions. Terms and Conditions