This site is intended for health professionals only

Vaginal thrush: dealing with a common irritation

Maryam Fernandez
RGN BA(Hons)
Education and Development Officer for Practice Nurses
Chingford, Wanstead and Woodford PCT
E:maryamfernandez@hotmail.com

Candidiasis is a fungal infection caused by a species of the yeast Candida. The Candida yeast can live harmlessly in many human tissues including the vagina. Changes in the vaginal environment can cause profuse growth and colonisation of Candida leading to infection and symptoms. The species that most commonly causes vulvovaginal candidiasis (VVC) is Candida albicans, which is responsible for 90% of ­infections.(3,4)

Symptoms
Typical symptoms of VVC are vulval and vaginal itching. An abnormal vaginal discharge that is commonly white and "curd"-like may also be present. It is important to be specific when discussing any abnormal vaginal discharge as other infections such as bacterial vaginosis may need to be excluded by microscopy and culture at a GUM (genitourinary medicine) clinic.(5) Vaginitis, fissuring, vulval erythema, swelling and vaginal discharge may or may not be noticeable on ­examination.
Symptoms usually develop quickly, often in the week before menstruation in nonpregnant women. Dysuria and/or dyspareunia are other possible symptoms so it is important to take a full history.
Recurrent infection may cause psychosexual problems for which referral for specialist counselling should be considered.
Up to 10-20% of women may harbour Candida but suffer no symptoms. These women do not require ­treatment.(6)

Predisposing factors

  • Candida is opportunistic, growing in warm, moist areas of the body and flourishing in damaged human membranes and skin.
  • The use of antibiotics and immunosuppressives can affect harmless bacteria in the vagina which ­normally keep Candida growth in check, thus ­predisposing women to thrush.
  • Poorly controlled diabetes is another possible risk factor, in particular for recurrent vaginal thrush (four or more episodes a year). Hyperglycaemia increases the ability of Candida albicans to bind to epithelial cells in the vagina.(7)
  • Hormonal changes before the menstrual period and during pregnancy can also increase ­susceptibility to vaginal thrush. It is thought to be more common in pregnant women.
  • The frequency of vaginal thrush increases with age after menarche, peaking at the third and fourth decade of life.(1,3)
  • The role of behavioural factors such as wearing tight synthetic underwear, frequency of sexual activity,(8) and the taking of oral contraceptives,(1) are unclear due to insufficient research in this area. In one study condom use was found to be a risk ­factor, possibly due to the spermicide altering the vaginal flora, enabling adhesion of Candida ­organisms.(9)

Transmission
The majority of cases of vaginal Candida infection result from a person's own resident vaginal Candida organisms overgrowing and causing symptoms. It is possible but uncommon for Candida to be passed from person to person through sexual intercourse. Men can also suffer from penile candidiasis although asymptomatic male partners of women with VVC need not be examined, swabbed or treated.(1)
 
Diagnosis
In general practice vaginal thrush is commonly diagnosed on the basis of symptoms of acute vulval pruritus and vaginal discharge alone. However, VVC cannot reliably be diagnosed unless signs, symptoms (in particular pruritus), and a positive vaginal Candida culture are present.(1)
Awareness of differential diagnosis is important as any number of sexually transmitted diseases (STDs) may produce a vaginal discharge. In addition, acute vulval pruritus may be a symptom of herpes simplex, contact dermatitis or allergy. Any possibility of STD requires a full sexual health screen or referral to a GUM clinic. Where there is no possibility of STD and typical symptoms of VVC are present it is not necessary to take swabs, unless there are suspicions of a resistant organism, the treatment has failed or it is a recurrent episode. Where there is a coexisting illness, such as diabetes, vaginal swabs are routinely taken.
Recurrent VVC also necessitates a vaginal swab as the species Candida glabrata may be responsible and requires specific treatment. Male partners of women with recurrent VVC may have penile candidiasis; however, studies show no evidence that treating male sexual partners prevents recurrence of VVC in women.(10)
There is uncertainty as to why some women suffer recurrent attacks. Some research suggests that where Candida glabrata is responsible, recurrence may be due to its low sensitivity to imidazoles - commonly prescribed antifungal drugs.(3) There may have been noncompliance or inadequate previous treatment for the infection. Investigation of recurrent vaginal thrush requires a clinical examination, swabs and consideration of any underlying illness.
If taking a vaginal specimen for Candida culture, the swab should be taken from discharge from the lateral vaginal wall and can be stored at room temperature for up to 24 hours, after which time the yeast may not survive.

Treatment and management options
Isolated acute episodes of VVC

Many antifungal treatments (antimycotics) for VVC are available over-the-counter (OTC). However, women commonly self-misdiagnose and there is evidence from studies that up to two thirds of all OTC drugs sold to treat VVC were used by women who did not have the infection. There is debate over whether unnecessary use of these drugs may lead to resistant infection, which is in turn very difficult to treat.(11) It is preferable therefore to correctly diagnose before treating vaginal thrush. Treatments include:

  • Azoles (topical and oral) - these give an 80-85% cure rate in nonpregnant women with acute VVC.(11)
  • Nystatin - gives a 70-90% cure rate in ­nonpregnant women with acute VVC.(11)

Most women respond to topical treatments (cream and/or pessaries) of azoles or nystatin. Treatment duration varies from one to six nights for azoles and longer for nystatin. Studies have found no evidence of differences in response between either short- or long-term treatment regimens of intravaginal azoles.(12)
Oral treatments (eg, fluconazole and itraconazole) are convenient and effective but may take 12-24 hours for symptom relief. About 10% of women experience mild side-effects (such as headache) which wear off. Many short-course preparations are available that encourage compliance.

Treatment failure
Treatment failure in an isolated episode is usually due to poor compliance and another short course treatment may be offered. Otherwise, longer treatment regimens may be prescribed. Cultures of vaginal swabs will enable commencement of appropriate treatment. Combined topical and oral therapy is sometimes recommended. Other underlying conditions may be ­present and require consideration.

Recurrent VVC
Treatment for recurrent VVC is more complex and can involve an induction period (to reduce Candida and relieve symptoms) of at least 1 week of oral therapy or 1-2 weeks of topical therapy. A maintenance period of 6 months of topical or oral azole treatment can follow to prevent recurrence. On stopping ­treatment relapse may occur and a further induction and maintenance period may be necessary. Breakthrough infection during maintenance may point to azole resistance for which a specialist referral will be necessary.

During pregnancy
In mild cases during pregnancy simple home measures may be sufficient (see advice section below). Topical azoles are recommended for treatment of thrush as they are safe and effective. Research suggests that topical courses of 7 days are more effective than shorter courses.(3,5) There is not sufficient data about the safety of oral therapy in pregnancy.

The nurse's role in treatment and advice

Nurse prescribers who have trained to prescribe oral antibiotics from the nurse prescriber's extended formulary can only do so for specific medical conditions of which vaginal thrush is one. Information on the appropriate treatment combinations and regimens should be sought from appropriate guidelines. To encourage rapid relief of symptoms and prevent ­recurrence the following advice should be given:

  • Complete the full treatment course even during menstruation and if symptoms improve.
  • Be aware of possible damaging effects of topical treatments on barrier methods of contraception and anecdotal evidence of long-term azole use on oral contraceptive efficacy.
  • To relieve discomfort wear loose-fitting, cotton underwear and avoid wearing nylon tights.(5)
  • Maintain regular but not excessive hygiene of the vulval area with water.
  • Avoid using perfumed or soap products on the ­vulval area to prevent further irritation.
  • Yoghurt containing Lactobacillus administered vaginally (with the use of a tampon) or orally may, anecdotally, help reduce symptoms. However, there is no evidence of its effectiveness in the treatment or prevention of vaginal thrush.
  • Return if symptoms are not improved by the above measures or if they recur in order to reassess ­management options.

Conclusion
Vaginal thrush is a common condition which may or may not cause irritating symptoms to women. Rapid symptom relief is the primary goal of treatment in isolated cases. Recurrence can occur for various reasons, which require investigation and specialised treatment regimens.

[[nip12_cs_66]]

[[NIP12_pp_68]]

References

  1. Denning DW. Management of ­genital candidiasis. Working Group of the British Society for Medical Mycology. BMJ 1995;310:1241-4.
  2. Sobel JD. Epidemiology and ­pathogenesis of recurrent vulvovaginal candidiasis. Am J Obstet Gynecol 1985;152:924-35.
  3. Sobel JD, Faro S, Force RW, et al. Vulvovaginal candidiasis: ­epidemiologic, diagnostic, and ­therapeutic considerations. Am J Obstet Gynecol 1998;178:203-11.
  4. Oriel JD, Partridge BM, Denny MJ, Coleman JC. Genital yeast infections. BMJ 1972;iv:761-4.
  5. Clinical Effectiveness Group. National guidelines for the ­management of ­vulvovaginal ­candidiasis. Clinical Effectiveness Group. 2001. Available from URL: http://www.agum.org.uk/
  6. Butler C. Not all vaginal discharge is thrush. Rapid response. 21 May 2003. Available from URL: http://bmj.com/cgi/letters/326/7397/993#32504
  7. Bohannon NJ. Treatment of vulvovaginal candidiasis in patients with diabetes. Diabetes Care 1998;21:451-6.
  8. Reed BD, Gorenflo DW, Gillespie BW, Pierson CL, Zazove P. Sexual behavior and other risk factors for Candida vulvovaginitis. J Womens Health Gend Based Med 2000;9:645-55.
  9. Eckert LO, Hawes SE, Stevens CE, Koutsky LA, Eschenbach DA, Holmes KK.Vulvovaginal candidiasis: clinical manifestations, risk factors, ­management algorithm. Obstet Gynecol 1998;92:757-65.
  10. Fong IW. The value of treating the sexual partners of women with ­recurrent vaginal candidiasis with ­ketoconazole. Genitourin Med 1992;68:174-6.
  11. Marrazzo J. Vulvovaginal ­candidiasis: over the counter treatment doesn't seem to lead to resistance. BMJ 2003;326:993-4.
  12. Marrazzo J. Extracts from "Concise clinical evidence" vulvovaginal ­candidiasis. BMJ 2002;325:586.

Resources
Prodigy Department of Health website dedicated to clinical ­governance on specific topics
W:www.prodigy.nhs.uk

Regularly updated collection of common clinical topics and related questions
W:www.clinicalevidence.com/

Eguidelines Collection of primary care ­clinical guidelines summaries
W:www.eguidelines.co.uk