Can Routine Histopathology Distinguish Between Vulvar Cutaneous Candidosis and Dermatophytosis?
OBJECTIVE
This study aimed to determine if vulvar cutaneous candidosis and dermatophytosis can be distinguished by routine histopathology.


METHODS
Twenty-four cases of periodic acid-Schiff-stained vulvar biopsies with a diagnosis of cutaneous mycosis were reviewed and histopathological characteristics on both periodic acid-Schiff and hematoxylin and eosin were recorded. Data were collected on age, clinical impression, microbiological results, and treatment, and all specimens underwent multiplex polymerase chain reaction analysis.


RESULTS
The mean age was 60 years, and all but 3 women had at least 1 risk factor for mycosis including 15 (62.5%) with lichen sclerosus and/or planus managed with topical corticosteroids. A clinical suspicion of tinea or candidosis was documented in 12 (50%) of the cases. Vulvovaginal swabs showed Candida species in 9 women; one skin scraping was positive for Trichophyton rubrum. Microbiology was not obtained in 8 patients, 5 had a negative swab, and 1 had negative skin scrapings. No histopathological or morphological features distinguished Candida species from dermatophytes. Organisms appeared as basophilic structures in the stratum corneum in 15 (62.5%) hematoxylin and eosin-stained slides. Polymerase chain reaction results were positive for Candida species in 5 (21%) and for dermatophytes in 3 (13%), negative in 13, and unassessable in 3 cases.


CONCLUSIONS
Vulvar cutaneous candidosis and dermatophytosis cannot be reliably distinguished by routine histopathology or specific polymerase chain reaction. A high index of suspicion combined with adequate microbiological testing remains the best approach to differentiating between the 2, which impacts on counseling, treatment, and prognosis.
1Maternity and Gynaecology, John Hunter Hospital; and 2Faculty of Health and Medicine, University of Newcastle, Newcastle, New South Wales; 3Department of Microbiology and Infectious Diseases Laboratory Services, Murdoch Children's Research Institute, Parkville; and 4Vulvar Disorders and Dermatology Clinic, Royal Women's Hospital, Melbourne; 5Riverina Dermatology, Wagga Wagga; and 6Anatomical Pathology, Pathology North, Hunter New England, Newcastle, New South Wales; and 7Faculty of Medicine, Dentistry, and Health, University of Melbourne, Parkville, Victoria, Australia.
Tania
T
Day
Ailsa
A
Borbolla Foster
Samuel
S
Phillips
Ross
R
Pagano
Delwyn
D
Dyall-Smith
James
J
Scurry
Suzanne M
SM
Garland
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003883:Arthrodermataceae / Q000302:isolation & purification; D001706:Biopsy; D002175:Candida / Q000302:isolation & purification; D002181:Candidiasis, Vulvovaginal / Q000175:diagnosis* / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D006651:Histocytochemistry / Q000379:methods*; D006801:Humans; D008828:Microbiological Techniques; D008853:Microscopy; D008875:Middle Aged; D012189:Retrospective Studies; D014005:Tinea / Q000175:diagnosis* / Q000473:pathology*; D055815:Young Adult