Sexually Transmitted Diseases

Question 1

Organism involved in genital herpes

Answer 1

HSV 1 and 2

1 mostly oral (10%)
2 mostly genital (90%)

Question 2

Description of genital herpes

Answer 2

Herpes simplex virus is a common STD, adult prevalence of HSV-2 is 22%, but most are asymptomatic. Clinically infections can be primary, nonprimary first episode (HSV-2 infection after HSV-1) and recurrent infection. Transmission: between asymptomatic Pt with a break of epithelium and those with ulcers.

Incubation <14 days

Question 3

Clinical Presentation of genital herpes

Answer 3

Asymptomatic
Classically there is multiple painful blisters/ulcers that may be vesicular. Can be associated with dysuria, urine retention, local lympadenopathy, discharge, anorectal spasm. They have prodrome symptoms. These resolve over 2 weeks but reoccur.

Question 4

Investigations for genital herpes

Answer 4

PCR swab/scrap (100% SEN) in the first 48 hours hence, most Dx are clinical.
Clinical diagnosis is unreliable

Pregnancy: If there is a lesion present do a C-section (due to encephalopathy risk).

Question 5

Management for genital herpes

Answer 5

Pain: Topical lignocaine 
PLUS 
Aciclovir 400mg for 5days
OR 
Famciclovir 250mg for 5days
OR 
Valaciclovir 500mg for 5days

Recurrent: Aciclovir for 4/12

Question 6

Organism involved in Chlamydia

Answer 6

Chlamydia trachomatis (intracellular parasite)

Question 7

Description of Chlamydia

Answer 7

Chlamydia trachomatis is the most common bacterial cause of sexually transmitted infections among men and women. Risk factors include young age, multiple sexual partners, limited use of barrier contraceptives and Hx of prior STDs. The incubation period is 7-14 days.

Question 8

Clinical Presentation of Chlamydia

Answer 8

Asymptomatic (50%)
Cervicitis, vaginal discharge mucopuruent, intermenstrual bleeding and post-coital bleeding (left d/c from the os) Dysuria-pyuria UTI symptoms PID (30% of those untreated) Perihepatitis (5-15%)

Question 9

Investigations for Chlamydia

Answer 9

Nucleic acid amplification (NAAT) from first catch urine (males) or vaginal swabs (female) is the gold standard aka PCR.

Question 10

Management for Chlamydia

Answer 10

Doxycycline 100 mg for 7 days
OR
Azithromycin 1g oral stat (in pregnant)

A second course may be indicated

Question 11

Organism involved in Syphilis (condyloma lata)

Answer 11

Traponema pallidum (Gram -ve spirochaete)

Question 12

Description of Syphilis (condyloma lata)

Answer 12

Syphilis is a chronic infection with a bacterium that can be early with the stages of syphilis (10, 20 and early latent) or latent. It is spread by sexual, contact, IVDU, open lesions, transplacental and is commonest in MSM.

Incubation ∼21 days

Question 13

Clinical Presentation of Syphilis (condyloma lata)

Answer 13

Asymptomatic
Primary (21 days):
Chancre, a painless ulcer at the site of entry

Secondary (2-3 months):
Systemic maculo-papular rash on soles of feet and palms of hand, fever, alopecia and LN
Can go Latent: +ve serology, no signs

Tertiary (>3years):
Neurological disease, gummas of any organ or CVS disease.

Question 14

Investigations for Syphilis (condyloma lata)

Answer 14

The organism has never been cultured in vitro…
Primary: Chancre biopsy, with dark field microscopy

Secondary: Serology, both nontrepnemal and trepnemal tests.

Screening: VDRL
Diagnosis: TPHA3

Question 15

Management for Syphilis (condyloma lata)

Answer 15

Penicillin for single dose or 10 days

Singe dose for 1 or latent Long-acting for those of unknown duration

Question 16

Organism involved in Gonorrhoea

Answer 16

Neisseria gonorrhoea (Gram -ve intracellular diplococci)

Question 17

Description of Gonorrhoea

Answer 17

Gonorrhoea is a major cause of urethritis in men and cervicitis in women, which can cause PID, infertility, ectopic pregnancy and chronic pelvic pain.Affects endometrium, oropharynx, conjunctitia, rectum.

Incubation 2-7 days

Question 18

Clinical Presentation of Gonorrhoea

Answer 18

Asymptomatic (60% but 10% of men)

Women: Gonorrhoea in women can involve any part of the genital tract, oropharynx or become disseminated.

Associated with bloodly coloured discharge.

Men: discharge and dysuria.

Question 19

Investigations for Gonorrhoea

Answer 19

Endocervical swab with culture and sensitivities. Culture of the anus, oropharynx, abscess Urine (first catch)

Question 20

Management for Gonorrhoea

Answer 20

Ceftriaxone 500 mg stat

PLUS

Azithromycin 1g oral stat

OR

Doxycycline 100 mg for 7 days
Follow up, re-swab in 7/7.

Question 21

Organism involved in Genital warts (condyloma acuminatum)

Answer 21

HPV

Esp 6 & 11

Question 22

Description of Genital warts (condyloma acuminatum)

Answer 22

Human papillomavirus in the genital tract is largely asymptomatic and transient, detectable only by changes seen on cytology in the Pap smear, colpsocopy or HPV-DNA testing. The incidence of HPV is 50% UNI students with a lifetime risk of 80%.

Incubation weeks to months.

Question 23

Clinical Presentation of Genital warts (condyloma acuminatum)

Answer 23

Asymptomatic
Genital warts that are skin colored or pink that range from smooth flattened papiles to papilliform.
Associated with pain, pruritus and bleeding.
Polps can be in anus or around opening of urethra

Question 24

Investigations for Genital warts (condyloma acuminatum)

Answer 24

Clinical Dx

HPV typing Histology (if unsure)

Question 25

Management for Genital warts (condyloma acuminatum)

Answer 25

Periodic Cryotherapy
OR 
Imiquimod 5% cream
OR
Podophyllotxin 0.15% cream

Recurrence rate 40%

Question 26

Organism involved in HIV

Answer 26

Human immunodeficiency virus (retrovirus)

Question 27

Description of HIV

Answer 27

HIV infection causes a clinical syndrome characterised by the development of progressive immunodeficiency following a long asymptomatic period. Cellular immunodeficiency leads to opportunitic infection and, more rarely, cancer. AIDS is defined as CD4 > 200 and HIV +ve

Incubation is 14 days

Question 28

Clinical Presentation of HIV

Answer 28

Seroconversion (30-80%) occurs at 2-4 weeks and results in fever, malaise and maculopapular rash.
Asymptomatic period
Symptomatic results in opportunistic infections and cancer (Kaposi’s sarcoma & NH lymphoma).

Question 29

Investigations for HIV

Answer 29

Detection of anti-HIV antibodies by ELISA.

3-month period where serology is negative.

Question 30

Management for HIV

Answer 30

HAART (highly active anti- retroviral therapy) has decreased mortality. Commonly:Two NRTIs + one PI/NNRTI

Pregnancy: Prevent vertical transmission with HAART (5% risk). Breast feeding is high risk.

Question 31

Organism involved in Scabies

Answer 31

Sarcoptes scabei (mite)

Question 32

Description of Scabies

Answer 32

Scabies is an infestation of the skin by a mate that results in an intensely pruritic eruption with a characteristic pattern. Transmission is by direct contact, in young adults this is sexual contact. Symptoms begin 3-6 weeks of infestation, due to a delayed type IV hypersensitivity

Question 33

Clinical Presentation of Scabies

Answer 33

Pruritus in distribution with small erythematous, nondescript papules often tipped with hemorrhagic crusts.

Question 34

Investigations for Scabies

Answer 34

From the HX and distribution of lesions. Microscopyof mites.

Question 35

Management for Scabies

Answer 35

Topical permethrin 5% cream
OR
Topical benzl benoate emulsion 25%

Question 36

Organism involved in Genital lice (crabs)

Answer 36

Pediculosis pubis (louse)

Question 37

Description of Genital lice (crabs)

Answer 37

Pediculosis pubis is usually transmitted through sexual contact. Infection of an eye lash many occur.

Question 38

Clinical Presentation of Genital lice (crabs)

Answer 38

Pruritus in the pubic area, but also the axillae

Question 39

Investigations for Genital lice (crabs)

Answer 39

Presence of pediculosis pubis ornits(louse eggs)on microscopy.

Question 40

Management for Genital lice (crabs)

Answer 40

Topical permethrin 1% cream
OR
Topical pyrethrins with piperonyl butoxide