Microbiology

Question 1

Which bacteria make up the normal viginal flora?

Answer 1

• Lactobacillus spp. predominate in the “healthy” vagina and produce:
• Lactic acid ] these suppress growth
• +/- hydrogen peroxide ]of other bacteria
• Other organisms

+/-Strep “viridans” – different species within this group

+/- Group B beta-haemolytic Streptococcus

+/- Candida spp. (small numbers)

Question 2

what is the main cause of thrush?

How is it treated?

Answer 2

•C. albicans

topical clotrimazole

or

oral fluconazole

Question 3

what are the symptoms of bacterial vaginosis?

what is the main causitive organism?

How is the diagnosis made?

What is the treatment?

Answer 3

•Thin, watery, fishy-smelling vaginal discharge

Gardnerella Vaginalis

Diagnosis is Clinical, Ph is also raised over 4.5. Lab test unreliable but Clue cells (epithelial cells covered in Gardnerella) are detected.

Oral Metronidazole

Question 4

For bacterial prostatitis what are the symptoms?

Causes?

Diagnoses?

And treatment?

Answer 4

• Symptoms of UTI, but may have lower abdominal pain/back/perineal/penile pain and tender prostate on examination
• Rare complication of UTI in men
• Same organisms as UTI (E. coli & other coliforms, Enterococcus sp., but check for STI in patients <35years (gonorrhoea, chlamydia)
• Diagnosis – Clinical signs + MSSU for C&S (+/- first pass urine for chlamydia/gonorrhoea tests)
• Rx – ciprofloxacin for 28 days (altered depending on culture result). Trimethoprim (28d) if high C. diff risk

Question 5

what is the histological appearnace of a chlamydia infection?

Answer 5

Gram negative diplococci

Question 6

where are the sites of infection for chlamydia?

Answer 6

Eyes, Throat, Vaginal, Anal

Question 7

how could chlamydia present in men and woman?

Answer 7

In Males:

Urethritis

Epidiymo-orchitis

Urethral discharge

Dysuria

In Females:

Post coital or intermenstrual bleeding

Lower abdominal pain

Dyspareunia

Mucopurulent cervicitis

Question 8

what is the diagnosis and treatment of chlamydia?

Answer 8

Test 14 days following exposure

NAAT- females (vulvovaginal swab), males (first void urine)

MSM (add rectal swab if has receptive anal intercourse)

Azithromycin 1G stat

Doxycycline 100mg BD x 1 week

Question 9

what is the gram stain appearance of gonorrhoea?

Answer 9

gram negative diplococci

Question 10

WHERE ARE THE SITES OF A GONORRHOEA INFECTION?

Answer 10

urethra, endocervix

rectum and pharynx

Question 11

what are the symptoms of a gonorrhoea infection in males and females?

Answer 11

males:

Asymptomatic - ≤10%

Urethral discharge – >80%

Dysuria

Pharyngeal/rectal infections – mostly asymptomatic

Females:

—Asymptomatic (up to 50%)

—Increased/altered vaginal discharge (40%)

—Dysuria

—Pelvic pain (<5%)

Pharyngeal and rectal infection are usually asymptomatic

Question 12

how is gonorrhoea diagnosed?

Answer 12

PCR

Question 13

what is the treatment for gonorrhoea?

Answer 13

First-line: Ceftriaxone 500 mg IM

Second-line: Cefixime 400 mg oral (only if IM injection is contra-indicated or refused by patient)

Co-treatment: Azithromycin 1g (regardless of Chlamydia result) given at the same time as gonorrhoea treatment

Test of cure in all patients

Question 14

what are the current tests in tayside for syphillus?

Answer 14

Question 15

describe how IGM, VDRL and TPPA results would come back on different stages of siph.

Answer 15

Question 16

describe the diagnoses of chlamydia and gonorrhoea?

Answer 16

• Combined nucleic acid amplification tests (NAATs) or polymerase chain reaction test (PCR) – tests for both organisms in 1 test
• Highly sensitive and specific tests
• Done on:
• Male patients – first pass urine sample (N.B. not MSSU)
• Female patients – HVS or vulvo-vaginal swab (VVS), which can be self-taken by patient or clinician-taken or endocervical swab (if patient is having speculum examination)
• Rectal and throat swabs
• Eye swabs (babies and adults)

Question 17

how do you treat syphilis?

Answer 17

Early Syphilis

2.4 MU Benzathine penicillin x 1

Late Syphilis

2.4 MU Benzathine penicillin x 3

Question 18

what is the follow up test for syphilis?

Answer 18

rpr

rapid plasma reagin

for antibodies

should go down 4 fold within 3-6 months

Question 19

describe the symptoms and timing of a genital herpes infection

Answer 19

Incubation - 3-6 days

Duration - 14-21 days

lBlistering and ulceration of the external genitalia

lPain

lExternal dysuria

lVaginal or urethral discharge

lLocal lymphadenopathy

lFever and myalgia (prodrome)

Question 20

how would you manage a herpes infection?

Answer 20

Swab base of ulcer for HSV PCR

Give oral antiviral Treatment (Aciclovir)

Consider topical Lidocaine 5% ointment if very painful

Saline bathing

Analgesia

Question 21

what is are the HPV viruses that cause the most anogenital warts?

Answer 21

HPV 6 & 11

Question 22

what is the treatment of anogenital warts?

Answer 22

podophyllotoxin cream

cryotherapy

Question 23

what is trichomonas vaginalis?

what symptoms does it cause?

How is it diagnosed?

What is the treatment?

Answer 23

• Single celled protozoal parasite
• divides by binary fission (no cyst form is known) – human host only
• Transmitted by sexual contact
• Causes vaginal discharge and irritation in females (and ?urethritis in males)
• Diagnosis
• High vaginal swab for microscopy (PCR test also available, but not used in Tayside, so no good test for males)
• Treatment
• Oral metronidazole