Reproductive tract infections Flashcards
Describe the key clinical features of pelvic inflammatory disease
Pelvic pain, fever, vaginal discharge
Complications include spontaneous abortions, salpingitis tubo-ovarian abscesses and peritonitis
Describe the pathogenesis of pelvic inflammatory disease
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.
List the organisms which can cause pelvic inflammatory disease
Gonococcus (N. gonorrhoea)
Chlamidya trachomatis
Polymicrobial (staphylococci, streptococci, and C. perfringens)
List the factors which predispose individuals to pelvic inflammatory disease
Sexually transmitted infections (Chlamydia, gonorrhoea)
childbirth
abortion or miscarriage
What are the most common causes of urethritis in men
Neisseria gonorrhoea
Chlamydia trachomatis
Ureaplasma urealyticum
Myocoplasma genitalium
Name 4 complications of chlamydia infection
Pelvic inflammatory disease
Infertility
Ectopic pregnancy
Chronic pelvic pain
Neionatal pneumonitis
Opthalmia neonatorum
Describe the pathogenesis of chlamydial infection
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.
Describe the clinical presentation of Chlamydia
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
What investigations are required for suspected chlamydial infection?
Cell culture: gram negative. Expensive
Immunofluorescence:
Immunoassay
PCR - plasmid or nuclear antigen
Samples: Urethra, endocervix
How do you treat chlamydial infection?
Tetracyclines or macrolines
- Doxycycline 100mg 2x for 7days, AZT 1g single dose
Describe the pathoegenesis of gonococcal infection
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.
Describe the clinical presentation of gonorrhoea infection
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.
What investigations are required for suspected gonorrhoea infection?
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
How is a gonoccocal STI treated?
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.
Non-specific urethritis
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
Describe the pathogenesis of syphillis
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.
How is syphillis diagnosed?
Detection of treponema pallidum with dark-ground microscopy
Direct fluorescent antibody test
PCR
Serology
How is syphillis treated?
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)
Name 4 infective causes of vaginal discharge
Chlamydia trachomatis
Neisseria gonorrhoea
Trichomonas vaginalis
Bacterial vaginosis
Candida albicans
Common conditions associated with chlamydia in infants
Pre-term delivery and low birth weight
Opthalmia neonatorum
Neonatal pneumonitis
Symptoms associated with chlamydia in men
Non-specidic rethritis
Penile rash
Testicular pain (orchitis and epididymitis)
Joint pain or swelling (reactive arthritis)
Name two ulcerative STIs
Genital herpes
Syphilis
Describe the clinical presentation of genital herpes
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.
Describe the pathogenesis of genital herpes infection
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.
How is genital herpes diagnosed?
culture of virus from a lesion
HSV DNA detected by PCR or RT-PCR
What is the treatment for genital herpes?
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
Trichomoniasis
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
Candidiasis
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)
Bacterial vaginosis
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
Causes of candidiasis
Pregnancy
Broad spectrum anti-bitoics
Immunosuppression
Diabetes mellitus
Cushings
Synthetic underwear
