Definitions for the level of evidence (I-IV) and grade of recommendation (A-C) are provided at the end of the "Major Recommendations" field.
Who to Test and Treat?
Screening is not required for asymptomatic women (Evidence Level IV, Grade of Recommendation C).
Episodic Vulvovaginal Candidiasis (VVC)
Episodic VVC includes normal women with mild-moderate symptoms and no history of persistent or recurrent symptoms (Evidence Level IV, Grade of Recommendation C).
Symptoms suggestive of episodic VVC include external dysuria, vulval pruritus, swelling or redness. Signs include vulval oedema, fissures, excoriation, or thick curdy discharge. The vaginal pH is usually normal (Evidence Level III, Grade of recommendation B).
- Testing is recommended for episodic VVC whenever possible (Evidence Level III, Grade of Recommendation B).
- Treatment is clearly indicated for symptomatic women who are microscopy positive and/or those who are culture positive (Evidence Level III, Grade of Recommendation B).
- Treatment on the basis of symptoms alone is common clinical practice but results in the over-treatment of a large number of women (Evidence Level III, Grade of Recommendation B).
Complicated VVC
This includes; severe episodic VVC, persistent non-Candida albicans infection, recurrent VVC and those with underlying host abnormality (e.g., pregnancy, HIV infection and diabetes) (Evidence Level IV, Grade of Recommendation C).
As well as microbiological testing women with chronic symptoms need a careful history and examination. Particular attention needs to be paid to alternative diagnoses, most commonly vulval eczema/dermatitis. Possibilities otherwise include other causes of vaginal discharge (e.g., recurrent bacterial vaginosis and also recurrent herpes, vulval vestibulitis syndrome and other vulvar dermatoses) (Evidence Level III, Grade of Recommendation B). More than one condition may occur and this may vary with time (e.g., the patient may cycle between bacterial vaginosis and VVC). A general examination of the skin can sometimes be very helpful (Evidence Level IV, Grade of Recommendation C).
Recommended Tests
Except in research settings samples are almost universally taken with a cotton tipped swab from the vaginal wall.
Possible Uncomplicated VVC
In the context of specialist services offering a comprehensive sexual health service routine microscopy and culture is the standard of care for symptomatic women (Evidence Level III, Grade of Recommendation B).
A vaginal swab taken from the anterior fornix (Evidence Level III, Grade of Recommendation B).
- Gram or wet film examination (Evidence Level III, Grade of Recommendation B)
- Directly plated to solid fungal media. Speciation to albicans/non albicans is strongly preferred (Evidence Level III, Grade of Recommendation B).
- Vaginal pH is not useful in the diagnosis of VVC which can coincide with bacterial vaginosis (BV) (Evidence Level IV, Grade of Recommendation C).
Blind (Evidence Level III, Grade of Recommendation B) or self taken swabs (Evidence Level IV, Grade of Recommendation C) may be useful if directly taken swabs are not easily taken and if examination is not deemed necessary.
Complicated Disease
Tests for individual episodes as above.
- Speciation to albicans/non albicans is essential and should be performed to species level if a non-albicans species is isolated on more than one occasion (Evidence Level III, Grade of Recommendation B).
- Self taken swabs are useful in obtaining culture evidence of recurrent/persistent VVC. These can be taken when the patient is symptomatic before treatment and can be combined with a symptom diary as part of the assessment process (Evidence Level IV, Grade of Recommendation C).
Recommended Sites for Testing
- If a speculum is being passed then a cotton tipped swab should be used to take a sample from the anterior fornix (Evidence Level III, Grade of Recommendation B).
- If speculum is not being passed then blind (Evidence Level III, Grade of Recommendation B) or self taken swabs may be used (Evidence Level IV, Grade of Recommendation C)
Processing of Samples
Microscopy should be of either a Gram stained or Wet mount preparation (Evidence Level III, Grade of Recommendation B). Culture should be from a directly plated solid fungal media (Evidence Level III, Grade of Recommendation B). Chromogenic agar if available enables easy identification of species and mixed species infection and is preferred for investigation for complicated VVC (Evidence Level III, Grade of Recommendation B).
Liquid culture media are not recommended as they do not allow semi-quantitation. Other methods of testing for Candida such as latex agglutination have not made their way into routine clinical practice. PCR is currently of use only as a research tool.
Antifungal Sensitivities
There is no proven utility of antifungal sensitivity testing for complicated VVC (Evidence Level III, Grade of Recommendation B). It is possibly indicated for women with:
- A chronic immunological abnormality (Evidence Level III, Grade of Recommendation B)
- Repeated isolation of a non-albicans yeast (Evidence Level IV, Grade of Recommendation C).
Reporting of Results
Microscopy should be reported as fungal pseudohyphae and/or blastospores present or absent (Evidence Level III, Grade of Recommendation B).
Cultures should be reported as (Evidence Level III, Grade of Recommendation B):
- Negative
- Light growth <10 colonies per plate
- Moderate growth 10 to 99 colonies per plate
- Heavy growth >100 colonies per plate
Interpretation of Results
In interpreting results the possibility of Candida being an "innocent bystander" needs to be considered (i.e., that symptoms from another condition are wrongly attributed to coincidental asymptomatic isolation of Candida) (Evidence Level IV, Grade of Recommendation C).
Isolation of Candida is common in asymptomatic women. Treatment is not indicated in the absence of symptoms (Evidence Level III, Grade of Recommendation B).
Symptoms correlate with hyphal burden, and the presence of pseudohyphae and/or blastospores on light microscopy implies a relatively high fungal burden. Microscopy is therefore relatively specific but insensitive in the diagnosis of VVC (Evidence Level III, Grade of Recommendation B). In contrast culture is sensitive but not specific. Symptoms are not clearly associated with colony counts of <10 colonies/plate (Evidence Level III, Grade of Recommendation B).
Severity of individual episodes is based on clinical and not laboratory data. Severe disease may however require more intensive treatment Evidence Level Ib, Grade of Recommendation A).
Non-albicans species, most commonly C. glabrata, are isolated in 5-10% of episodic VVC but cannot be distinguished from C. albicans on clinical criteria (Evidence Level III, Grade of Recommendation B). They are inherently relatively azole resistant and may not respond well to conventional courses of antifungal treatment (Evidence Level III, Grade of Recommendation B).
Recurrent VVC is defined as four or more attacks of VVC in a year (Evidence Level IV, Grade of Recommendation C). It is usually due to C. albicans. Although there is evidence of persistence of infection between attacks using PCR (so called vaginal relapse) culture is negative between attacks. A diagnosis of recurrent VVC therefore requires either positive microscopy or a moderate/heavy growth of C. albicans, when symptomatic, on at least two occasions with treatment and at least partial resolution of symptoms in between (Evidence Level IV, Grade of Recommendation C).
Persistent VVC is usually due to non-C. albicans yeast. Risk factors include underlying host abnormality and being peri-menopausal. Diagnosis of persistent/chronic non-albicans infection requires isolation of the same species of yeast on at least two concurrent samples and treatment on the first occasion (Evidence Level IV, Grade of Recommendation C).
Recommendation for Test of Cure
Tests of cure are only indicated after the treatment of persistent non-albicans infection (Evidence Level IV, Grade of Recommendation C). Proof of cure requires at least two negative cultures at least a week after treatment and with an interval of at least a week between cultures (Evidence Level IV, Grade of Recommendation C).
Definitions:
Levels of Evidence
Ia: Evidence obtained from meta-analysis of randomised controlled trials
Ib: Evidence obtained from at least one randomised controlled trial
IIa: Evidence obtained from at least one well designed controlled study without randomisation
IIb: Evidence obtained from at least one other type of well designed quasi-experimental study
III: Evidence obtained from well designed non-experimental descriptive studies
IV: Evidence obtained from expert committee reports or opinions and/or clinical experience of respected authorities
Grading of Recommendations
- Evidence at level Ia or Ib
- Evidence at level IIa, IIb, or III
- Evidence at level IV
