Alexander McMillan1, 2
(1)
Department of Genitourinary Medicine, NHS Lothian, Edinburgh Royal Infirmary, Edinburgh, Uk
(2)
University of Edinburgh, Edinburgh, Uk
Alexander McMillanFormerly, Consultant Physician, part-time Senior Lecturer
Email: a.amcmm@btinternet.com
Abstract
Margaret (Case 11 and 24) returns to the Sexual Health clinic 6 years later with a 4 week history of vulval itch. Although she has had no recurrences of candidiasis for 3 years, she thought that candidiasis was the most likely cause of her symptoms and she self-medicated with oral fluconazole and topical clotrimazole, obtained over the counter from a pharmacy. Her symptoms, however, remain unchanged and she consults you for advice. When you examine her, the findings are similar to those described previously, but you decide to send a specimen of vaginal discharge to the laboratory to confirm the diagnosis.
Margaret (Case 11 and 24) returns to the Sexual Health clinic 6 years later with a 4 week history of vulval itch. Although she has had no recurrences of candidiasis for 3 years, she thought that candidiasis was the most likely cause of her symptoms and she self-medicated with oral fluconazole and topical clotrimazole, obtained over the counter from a pharmacy. Her symptoms, however, remain unchanged and she consults you for advice. When you examine her, the findings are similar to those described previously, but you decide to send a specimen of vaginal discharge to the laboratory to confirm the diagnosis.
A Gram-stained smear shows many blastospores but no hyphae (Fig. 26.1).
Figure 26.1.
Blastospores adherent to epithelial cells.
26.1 What Is the Most Likely Diagnosis, and What Is Your Immediate Management?
The finding of blastospores without hyphae suggests infection with C. glabrata. The clinical response of C. glabrata, the second most common isolate from women with recurrent vulvovaginal candidiasis, to topical or oral antifungal agents may be unsatisfactory. The minimum inhibitory concentrations (MICs) of the available azoles are generally higher for C. glabrata than for C albicans, and in many cases, there is frank resistance to fluconazole. Itraconazole has moderate activity against C. glabrata, but the MIC for the isolate does not always predict therapeutic success. In the treatment of vulvovaginal candidiasis caused by C glabrata itraconazole in an oral dosage of 200 mg twice daily for 7 days is the treatment of choice. If oral fluconazole or miconazole are used, prolonged courses are usually necessary; shorter courses or single-dose therapy should be avoided.
The mycology laboratory confirms that the infecting species is Candida glabrata. If itraconazole treatment fails to achieve cure, what other treatments might you consider?
When azole treatment of recurrent vulvovaginitis caused by C. glabrata has failed, boric acid (in a capsule containing 600 mg) inserted into the vagina once daily for 14 days has resulted in mycological cure rates of about 75%. If this treatment is successful, maintenance therapy in the form of nystatin pessaries, inserted into the vagina nightly, should be instituted. Maintenance therapy with boric acid (600 mg twice weekly) has also been used with some success. Prolonged absorption of boric acid, however, may cause systemic toxic effects such as anorexia, weight loss, skin rashes, and anemia, and its use should be confined to specialists. The safety of boric acid in pregnancy is uncertain, and it is recommended that its use should be discontinued 1–2 weeks before conception.
Amphotericin B 50 mg suppositories, one inserted into the vagina nightly for 14 nights has resulted in cure of about 70% of patients treated for vulvovaginal infection with non-albicans candidal infection. The treatment has been well tolerated.
Intra-vaginal flucytosine cream (17%) instilled nightly for 14 nights has also been used in the treatment of azole-resistant candidal infections, but this drug is not readily available, and experience in is use is very limited. There is also concern that drug resistance may rapidly develop.