Reproductive tract infections

Question 1

Describe the key clinical features of pelvic inflammatory disease

Answer 1

Pelvic pain, fever, vaginal discharge

Complications include spontaneous abortions, salpingitis tubo-ovarian abscesses and peritonitis

Question 2

Describe the pathogenesis of pelvic inflammatory disease

Answer 2

Pelvic inflammatory disease is an ascending infection that begins in the vulva or vagina and spreads upwards to involve most of the structures in the reproductive tract.

Question 3

List the organisms which can cause pelvic inflammatory disease

Answer 3

Gonococcus (N. gonorrhoea)

Chlamidya trachomatis

Polymicrobial (staphylococci, streptococci, and C. perfringens)

Question 4

List the factors which predispose individuals to pelvic inflammatory disease

Answer 4

Sexually transmitted infections (Chlamydia, gonorrhoea)

childbirth

abortion or miscarriage

Question 5

What are the most common causes of urethritis in men

Answer 5

Neisseria gonorrhoea

Chlamydia trachomatis

Ureaplasma urealyticum

Myocoplasma genitalium

Question 6

Name 4 complications of chlamydia infection

Answer 6

Pelvic inflammatory disease

Infertility

Ectopic pregnancy

Chronic pelvic pain

Neionatal pneumonitis

Opthalmia neonatorum

Question 7

Describe the pathogenesis of chlamydial infection

Answer 7

C. trachomatis is an intracellular pathogen.

Infection is initiated by attachment of a chlamydial elementary body to the hose cell, followed by its entry into the cell. The chlamydial elementary bodies are internalised in tight, endocytic vesicles and differentiate into reticulate bodies within the cell. These multuply and are reorganised into elementary bodies

When multiplication ceases, the cells rupture and the elementary bodies are released, attaching to other cells.

Question 8

Describe the clinical presentation of Chlamydia

Answer 8

Women: Abdominal pain, dysparunia, acute PID, vaginal discharge (cervicitis), post coital or intermenstrual bleeding, reactive arthritis

Men: Urethral discharge, penile rash, testicle pain (orchiditis, epididymitis), reactive arthritis

Infants: Opthammia neonatorum, preterm delivery and low birth weight

Question 9

What investigations are required for suspected chlamydial infection?

Answer 9

Cell culture: gram negative. Expensive

Immunofluorescence:

Immunoassay

PCR - plasmid or nuclear antigen

Samples: Urethra, endocervix

Question 10

How do you treat chlamydial infection?

Answer 10

Tetracyclines or macrolines

• Doxycycline 100mg 2x for 7days, AZT 1g single dose

Question 11

Describe the pathoegenesis of gonococcal infection

Answer 11

N. gonorrhoea is a gram negative intracellular diplococci which infects the epithelium of the urogenital tract, rectum and conjunctiva.

Humans are the only host and it is spread by physical contact.

Bacterial invasion causes non-specific acute inflammation characterised by neutrophils, oedema, lymphocytes and macrophages.

Question 12

Describe the clinical presentation of gonorrhoea infection

Answer 12

Usually symptomatic in men.

Spontaneous pustular/mucopus or clear mucus from the urethra. Most noticeable in the morning.

Dysuria, tender inguinal nodes. Rectal pain and discharge, pharyngitis, conjunctivitis

In women the primary site of infection is the endocervical canal, causing an increased or altered vaginal discharge, pelvic pain due to ascending infection, dysuria and intermenstrual bleeding.

Question 13

What investigations are required for suspected gonorrhoea infection?

Answer 13

Best time to investigate is early in the morning.

Examine for epididymo-orchitis

Swab the urethra - gram stain and culture

First voided urine sample for cytology, dipstick test and NAATs

Question 14

How is a gonoccocal STI treated?

Answer 14

Ceftriaxone 500mg IM and AZT 1g orally asap.
antibiotic choice is influenced by travel history or details from known contacts.

Longer courses of antibiotics are required for complicated infections.

Treatment also given to recent sexual partners.

Question 15

Non-specific urethritis

Answer 15

Males present with discharge and dysuria.

Non-specific diagnosis that responds to antibiotics, no cause found in 20-50% of patients. Contact tracing is important

Organisms: chlamydia t, ureaplasma urealyticum, M. genitalium, trichomonas

Question 16

Describe the pathogenesis of syphillis

Answer 16

Chronic systemic disease which can be acquired or be congenital.

Caused by Treponema pallidium, a motile spirochete that is aquired by sexual contact or via the placenta. The organism enters the new host through breaches in the squamous or columnar epithelium.

Primary stages: 10-90d p.i. a papule develops at the site of inoculation. This ulcerates. There is usually painless lymphadenopathy. Healing occurs spontanously in 2-3 weeks.

Secondary: between 4-10 weeks of the primary lesion fever, sore throat, malaise, generalised rash and arthralgia may appear. Can affect multiple organs. Warty plaque-like lesions founf in the perianal area.

Question 17

How is syphillis diagnosed?

Answer 17

Detection of treponema pallidum with dark-ground microscopy

Direct fluorescent antibody test

PCR

Serology

Question 18

How is syphillis treated?

Answer 18

Early syphillis should be treated with long-acting penicillin IM for at least 7 days.

Late stage syphillis requires an extended treatment course becomes teh treponemes divide even more slowly (requires longer therapy)

Question 19

Name 4 infective causes of vaginal discharge

Answer 19

Chlamydia trachomatis

Neisseria gonorrhoea

Trichomonas vaginalis

Bacterial vaginosis

Candida albicans

Question 20

Common conditions associated with chlamydia in infants

Answer 20

Pre-term delivery and low birth weight

Opthalmia neonatorum

Neonatal pneumonitis

Question 21

Symptoms associated with chlamydia in men

Answer 21

Non-specidic rethritis

Penile rash

Testicular pain (orchitis and epididymitis)

Joint pain or swelling (reactive arthritis)

Question 22

Name two ulcerative STIs

Answer 22

Genital herpes

Syphilis

Question 23

Describe the clinical presentation of genital herpes

Answer 23

Primary genital herpes: presents as erythematous papules which form into shallow painful bilateral ulcers. Ulcers have an erythematous edge with a grey-tinged base. Over 10-14days the lesions develop crusts and dry. Patients have severe external dysuria and tender inguinal lymphadenopathy. Systemic symptoms include fever, myalgia and headache

Recurrent attacks: milder and of shorter duration (8-12 days). Formation of unilateral ulcers, few vesicles and inguinal lymphadenopathy. Dysuria is uncommon. Precipitating factors vary.

Question 24

Describe the pathogenesis of genital herpes infection

Answer 24

There are two types of HSV. HSV1 is the major cause of cold sores and keratoconjunctivitis while HSV2 mostly causes genital herpes and systemic infections in the immunocompromised.

Infection is lifelong and can be primary or recurrent. The virus establishes latency in the dorsal root ganglia by ascending peripheral sensory nerves from the area of innoculation. On reactivation, the virus travels back down the nerve and begins replicating in the mucus membranes. Transmission occurs via close contact with a person who is shedding virus.

Question 25

How is genital herpes diagnosed?

Answer 25

culture of virus from a lesion

HSV DNA detected by PCR or RT-PCR

Question 26

What is the treatment for genital herpes?

Answer 26

Primary infection: 5 day course of antiviral
aciclovir 200mg 5x day
famciclovir 250mg 3x day
valaciclovir 500mg 2x day

Recurrent infection: course of antivirals for 6-12 months
Course of aciclovir 400mg 2x day or valaciclovir 250mg 2x day

Question 27

Trichomoniasis

Answer 27

T. vaginalis is a flagelated protozoon that attaches to squamous epithelium and infects the vagina and urethra.

Causes frothy yellow vaginal discharge and erythema of the vagina walls. The cervix may have multiple haemorrhagic areas (strawberry cervix).

Men usually present as asymptomatic sexual partners of infected women. May have urethral discharge, irritation or urinary frequency.

Diagnosed by swab of vaginal discharge which shows T. vaginalis and PMLs, or cervical cytology.

Treated with metronidazole

Question 28

Candidiasis

Answer 28

Caused by candida albicans. Commensal of the GU tract in women, pathogenesis caused by change in environment.

Causes a thick white vaginal discharge erythema and swelling of the vulva

Diagnosed by microscopic examination of a vaginal spear for the presence of spores. Culture of swabs.

Treatment can be topical or oral antifungals (azoles)

Question 29

Bacterial vaginosis

Answer 29

Disorder characterised by offensive, homogenous, white, adheerent vaginal discharge. Caused by a mixed flora of anaerobes (G. vaginalis, Bacterioides, M. hominis) replaces the normal lactobacilli of the vagina.

NOT a sexually transmitted disease

Diagnosed by characteristic vaginal discharge (fishy odour with KOH), amine test (raised vaginal pH due to breadown of amines)

Treated with metronidazole

Question 30

Causes of candidiasis

Answer 30

Pregnancy

Broad spectrum anti-bitoics

Immunosuppression

Diabetes mellitus

Cushings

Synthetic underwear