Infective causes of discharge Flashcards
What is thrush?
This is a yeast infection of the lower female reproductive tract.
What is the pathogenesis of thrush?
85-90% of cases are due to candida albicans. Other organisms include Candida glabrata, Candida tropicalis, Candida krusei and Candida parapsilosis.
Candida is a normal commensal organism in the vagina.
What are the risk factors for thrush?
Pregnancy DM Antibiotics use Foreign bodies Chemotherapy Contraceptives
Symptoms and signs of thrush
Pruritus vulvae Vulval soreness White 'cheesy' discharge Dyspareunia Dysuria (external) Vulval erythema- possibly with fissuring Vulval oedema Satellite lesions Excoriation
Differentials of thrush
BV Trichomonas vaginalis STIs Atrophic vaginitis Helminthic infection Lichen sclerosus Contact dermatitis Eczema Psoriasis UTIs Rectovesical fistula
Investigations for thrush
Routine vaginal swabs are not required, in suspected bacterial/resistant or complicated infection.
Take swabs from the anterior fornix or lateral vaginal wall and send for microscopy, culture and sensitivity.
Take midstream specimen of urine (MSU) if symptoms could be due to urinary tract infection.
Management of thrush
Use a soap substitute to clean the vulval area, wear loose-fitting underwear, prescribe either an intravaginal antifungal such as clotrimazole or miconazole.
Severe infections are treated with two doses of oral fluconazole (150mg).
Intravaginal clotrimazole or miconazole should be used in pregnancy.
Complications of thrush
Depression
Psychosexual problems
What is the definition of BV?
BV is caused by an overgrowth of predominantly anaerobic organisms in the vagina. The most common organisms include Gardnerella vaginalis, Prevotella spp.
BV is the most common cause of abnormal vaginal discharge in women of reproductive age.
Risk factors for BV
Sexual activity New sexual partner Other STIs Ethnicity Presence of a IUCD Vaginal douching Bubble baths Receptive oral sex Smoking.
Protective factors against BV
Condom use
COC
Circumcised partner
Presentation of BV
Offensive, fishy-smelling vaginal discharge without soreness or irritation.
Half of all women infected are asymptomatic.
There is usually a thin layer of white discharge covering the vaginal wall.
Differential diagnosis of BV
Other vaginal infection: candida, trichomoniasis, chlamydia, gonorrhoea, herpes simplex.
Other benign causes of vaginal discharge- physiological discharge, chemical irritants, foreign body, pregnancy, cervical ectropion.
Tumours of the vulva, vagina, cervix or endometrium
Postmenopausal vaginal discharge due to atrophic vaginitis
Vaginal discharge after gynae surgery.
Investigations for BV
Amsel’s criteria require at least three of the following for diagnosis:
i. Homogeneous discharge as above.
ii. Microscopy showing vaginal epithelial cells coated with a large number of bacilli (‘clue cells’).
iii. Vaginal pH >4.5.
iv. Fishy odour on adding 10% potassium hydroxide to vaginal fluid.
Clinical diagnosis
Management of BV
a. Advise avoidance of vaginal douching, advise against the use of shower gel, asymptomatic women usually do not need treatment unless they are pregnant.
b. Treatment options are:
Oral metronidazole 400-500 mg bd for 5-7 days. Treatment of choice. This may be used in pregnant women.
Oral metronidazole 2 g stat. Avoid in pregnant women.
Metronidazole vaginal gel 0.75% once daily for five days.
Clindamycin vaginal gel 2% once daily for seven days.
Oral tinidazole 2 g stat.
Oral clindamycin 300 mg bd for seven days.
Complications of BV
BV can increase the risk of acquiring and transmitting HIV and other STIs.
In pregnancy, BV is associated with various complications:
i. Late miscarriage
ii. Preterm delivery
iii. Premature rupture of membranes.
iv. Low birth weight
v. Postpartum endometritis
What is chlamydia?
Chlamydiae are small, obligate intracellular Gram-negative bacteria that infect human columnar and transitional epithelium.
Chlamydia trachomatis is responsible for:
i. Ocular infection (trachoma).
ii. Genitourinary infections.
iii. Proctitis.
iv. Sexually acquired reactive arthritis.
v. Lymphogranuloma venereum (a rare, sexually transmitted tropical infection causing genital ulcers and inguinal lymphadenopathy).
Prevalence of chlamydia
It is the most commonly diagnosed sexually transmitted infection (STI) in the UK and the most common preventable cause of infertility worldwide.
It is asymptomatic in approximately 50% of men and at least 70% of women.
Sequelae can, however, include pelvic inflammatory disease (PID), ectopic pregnancy, tubal infertility in women and proctitis, epididymitis and epididymo-orchitis in men.
Risk factors for chlamydia
Age <25 years. Sexual partner positive for chlamydia (two thirds of partners of people testing positive for chlamydia will test positive). Two or more sexual partners in the preceding year. A recent change in sexual partner. Lack of consistent use of condoms. Non-barrier contraception. Infection with another STI. Poor socio-economic status. Genetic predisposition.
