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Flashcards in STIs Deck (25):
1

STIs presenting with discharge (5)

Gonorrhea,
Chalmydia,
Trichomonas,
Candida,
Bacterial vaginosis.

2

STIs presenting with ulceration (5)

Painful:
- Herpes simplex,
- Chancroid
Painless:
- Syphilis,
- LGV
- Donovanosis (= granuloma inguinale = Klebsiella granulomatis).

3

Presenting with lumps or rashes

Genital warts (HPV),
Molluscum contagiosum,
Scabies,
Pubic lice.

4

Gonorrhoea:
Organism, Dx, Tx

Neisseria gonorrhoeae - intracellular G- diplococcus.
Gold standard: urine NAAT (PCR or similar).
Used to be culture from swabs.
IM ceftriaxone 500mg stat
+ 1g azithromycin stat
or (old): + 100mg doxycycline bd for 2 weeks.

5

Complications of Gonorrhoea

Bartholin's abscess,
Dissemination if complement def,
Ophthalmia neonatorum (neonatal conjunctivitis).

6

Chlamydia -
Organism and serovars

Chlamydia trachomatis - Intracellular G- bacterium.
Serovars Ab, B, Ba, C: trachoma (eyes);
D-K: Genital chlamydia (urethritis, PID) and ophthalmia neonatorum.
L1-3: LGV.

7

Complications of genital Chlamydia

- PID in 30% (involved in half of PID)
- Tubal factor infertility
- Ectopic pregnancy x9
- Endometriosis
- Reiter's syndrome
- Ophthalmia neonatorum and adult conjunctivitis

8

Chlamydia Dx and Tx

Urine NAAT.
Azithromycin 1g stat
(or Doxycycline 100mg bd for a week)
Partner notification and test for other STIs.

9

LGV - what is it and who gets it?

Lympho-granuloma venereum - serovars L1-3 of Chlamydia trachomatis.
MSM, or anyone abroad.

10

Stages of LGV

1: 3-12 days, painless ulcer, inflam.
2: 2 weeks, Painful inguinal buboes, can rupture. Fever, malaise, proctocolitis (pain, tenesmus, bleeding, d/c).
Late: Inguinal LN, abscesses, genital elephantiasis, frozen pelvis, rectal strictures.

11

LGV - Dx and Tx

Chlamydia NAAT then genotypic identification of serovar by PCR.
Doxycycline 100mg bd for 3 weeks.

12

Syphilis - organism

Treponema pallidum
G- spirochaete
Seen in primary lesions on dark background microscopy..

13

Syphilis - Test for current infection / success of treatment

Detect generic Antigens - VDRL and RPR.

14

Syphilis - Test which stays positive for years after infection

Detect Abs.
eg. Enzyme immunoassay, Fluorescent treponemal Ab, T p haemagglutination test, T p particle agglutination test.
More specific.

15

Primary Syphilis - features

One macule, then papule, then indurated painless ulcer.
Can stay for 4-6 weeks (chancre).
Clean base with serous exudate.
Regional LN.

16

Secondary Syphilis - features

Systemic bacteraemia
1-6 months after infection.
Low grade fever, malaise.
Rash: symmetrical, non-pruritic, everyhwere, maculopapular.
Snail track oral ulcers, uveitis, alopecia, warts. Neuro involvement.
"The great imitator"

17

Tertiary Syphilis - features

- Neurosyphilis (in HIV) 2-30 years later. Argyll-Robertson pupil (accomodates but does not react). General paresis of the insane.
- Gumma (granuloma) - rare. Type IV reaction 2-40 years later.
- Cardiovascular - inflam aortitis 2-30 years later, lots of spirochaetes.

18

Tx for Syphilis

Benzathine penicillin with procaine IM, stat.
(Doxycycline if allergic.)
4x reduction in RPR = success.
NB. Jarish-Heimer reaction on the day - rash, fever etc.

19

Chancroid -
Organism, feature, Dx

Haemophilus ducreyi (G- coccobacillus, like HiB).
Tropical ulcers (rare in UK), multiple, painful.
Dx by culture (chocolate agar) and PCR.

20

Donovanosis -
name, organism, geography, features, Dx, Tx

= granuloma inguinale,
by Klebsiella granulomatis (G- bacillus).
Africa, India, PNG, Australian aborigines.
Papule/nodule breaks down into large expanding ulcer. Beefy red.
Dx by Giemsa stain of biopsy, or tissue crush.
Tx: azithromycin.

21

Trichomoniasis

Trichomonas vaginalis - flagellated protozoan.
Discharge in woman. ^ risk of acquiring HIV.
Dx: wet prep microsopy, PCR.
Tx: metronidazole.

22

Bacterial vaginosis

Abnormal flora, many microbes, few lactabacilli.
Discharge, odour.
Not sexually transmitted. ?too rigorous hygeine.
Dx: Gram stain, whiff test, clue cells, raised pH.
Assoc preterm delivery.

23

Candidiasis

Usually candida albicans.
Thick white discharge, itching, red, sore.
Not sexually transmitted.
Tx: Topical or oral fluconazole.

24

Molluscum contagiosum

dsDNA poxvirus.
Hands and faces in children, skin to skin contact. Genital lesions in adults (so sexual contact).
Facial molluscum in adults = HIV.
Cryotherapy if required.

25

Genital warts

HPV 6, 11.
Incubation 3 weeks to 8 months.
Papular, planar, pedunculated, keratinised.
Podophyllotoxin / imiquimod / cryo.