The Relationship Between Vulvar Pruritus And Candida Albicans

The definition of "itch" was proposed by Samuel Hefrenreffer in1660as "an unpleasant sensation provoking the desire to scratch." Pruritus is the most common symptom of vulvar disorders in the clinics of dermatology and gynecology. Vulvar pruritus can be results of a variety of different conditions and affect normal work and study life of patients. The vulva can be afflicted by a variety of dermatoses and infective diseases, such as:contact dermatitis, eczema, vulvovaginal candidiasis (VVC), and bacterial vaginosis, et al.Of the many causes of vulvar pruritus, VVC is believed to be one of the most common causes. VVC is best defined as the spectrum of patients who harbor Candida organisms in their vaginas. Candida albicans is responsible for most symptomatic episodes of VVC. A broad variety of non-albicans species of Candida are encountered too, such as:Candida glabrata, Candida tropicadis, Candida parapsilosis, et al. Typical symptom of VVC are vulvar itching, flare and increasing of vaginal discharge. Recurrent vulvovaginal candidiasis (RVVC) is best defined as recurrent episodes of VVC more than4times per year. The latest statistical data of America in2007revealed that75%of females at least suffered one time of VVC along her life time, and40%～50%of females suffered two or more times.Although VVC is the most common cause of vulvar pruritus, the diagnosis of VVC depend on the clinical manifestation and laboratory examination. But many vulvar pruritus patients often self-use antifungal products for their pruritic symptoms, especially those who have a history of previous clinically based diagnosis of VVC. Among these patients, only proportion of patients are actually diagnosised as VVC. Whether patients with vulvar itching abuse antifungal drugs merit further research.C. albicans is the most common candida and is responsible for most symptomatic episodes of VVC. Although the incidence of C. albicans infection has decreased over the past because of the extensive use of antifungal products, it is still the most common pathogen among candida. The study about pathogenic mechanism of candida focus on C. albicans. Adhersion, enzymes and hyphal transformation are the most common virulence factor reaserched. Innate immunity, acquired immunity and hypersensitivity to C. albicans are the research priorities in the research of immuno logic pathogenic mechanism of WC.Some of the pruritus patients still have the sympom after the mycologic cure. Marinoff et al. examined13patients and demonstrated negative patch test results to a series of vehicles, preservatives and antifungals used in topical treatment of vaginal candidiasis. In the same study,10patients were tested with intradermal C. albicans antigen;1dermatographic patient had an immediate wheal response, and2patients showed a delayed type hypersensitivity response at48hr. No controls were reported. We propose that a previous candidal infection may alter the interaction between subsequent C. albicans antigen exposure and the cytokine milieu resulting in a hypersensitivity response localized to areas with a low (non-immunosuppressive) concentration of C. albicans. The culmination of these events may result in persistent vulvar pruritus. To obtain preliminary data relevant to this hypothesis, we patch tested and prick tested women with vulvar pruritus, using women with atopic dermatitis (AD) and dermatitis patients in our clinic as control groups. 1Etiology and medications self-use of female patients with pruritus vulvae1.1ObjectivesThe present study aims to estimate the etiology of pruritus vulvae and what proportion of pruritic women purchasing over-the-counter products for treatment of pruritus vulvae.1.2MethodsThe262women who complained of pruritus vulvae were evaluated by clinical examination and pertinent laboratory tests between February1,2011, and June31,2011. The accurate diagnosis were made according to the clinical examination and pertinent laboratory tests. Every women should finish one questionnaire including the use of over the counter products for treatment of pruritic symptom.1.3Results(1) Generral conditions of patientsVulvar pruritus status of the262female patients:The mean age of subjects was36years, and the range was18～80years. The age group concentrated in21-40years.205(78.2%) of women were married,59(22.5%) single. The mean persistent time of the pruritus symptoms was12.8months, and the range was1day～12years. The course of pruritus was increasing with the age. The age group of the longest course of pruritus was>50age groups.(2) The etiology of the vulvar pruritus The diagnosis of the262female vulvar pruritus patients was as followed:VVC (30.2%) was the most common infectious factors. VVC coexisting BV was the most common complexed infection. Among the nonseptic factors, contact dermatitis (7.6%) and eczema (6.1%) were the most common causes.(3)The self use of the topical products in patients with vulvar pruritus.There were157of262patients had history of topical drugs self use, and96of 157patients had history of topical antifungal products self use.(4)The self use of topical antifungal products in patients with vulvar pruritus.Only32of96(31.2%) women who self-used antifungal products made the correct diagnosis of VVC. Women with a previous clinically based diagnosis of VVC were not more accurate in diagnosing VVC than women without a prior clinical diagnosis(χ2=0.645, P=0.422). But women with a previous clinically based diagnosis of VVC often use antifungal products for their pruritic symptoms (x2=35.852, P=0.000)1.4Conclusions(1) The age group of female vulvar pruritus patients concentrate upon20-40years patients who are active in sexual life.(2) The cause of pruritus vulvae are varied, and VVC is the most common infectious causes of female patients with vulvar pruritus.(3) Women with pruritic symptoms often use over-the-counter antifungal products according to the history of clinically diagnosised VVC before an actual diagnoses, that add to health care costs and are unlikely to be of benefit.(4) It is of paramount importance to recognize that vulvar pruritus is a symptom and not a disease. Therefore, to manage patients optimally, a search for the cause of this symptom followed by appropriate treatment is of utmost importance. The abuse of antifungal products before accurate diagnoses may complicate the primary disease.2The relationship between vulvar itching and C. albicans hypersensitivity2.1ObjectivesTo investigate the relationship between vulvar itching and candidal hypersensitivity, we patch tested and prick tested women with vulvar pruritus, using women with atopic dermatitis (AD) and dermatitis patients in our clinic as control groups. 2.2Methods33patients with VVC and26patients with history of VVC were recruited within the dermatologic and gynecological clinics who complained of vulvar pruritus. All enroled patients completed the informed consent.We prepared C. albicans antigens in gelatin at the concentrations of0%、0.4%、1%、4%and20%. Subjects were patch tested with C. albicans allergen, and prick tested with commercialization of C. albicans allergen. Candida culture and CHROMagar Candida identification were used to identify the candida.2.3Results(1) Generral conditions of patientsThere were87subjects enroled in the experiments. The mean age of subjects was34years, and the range was20～72years. The degree of pruritus in VVC group patients:11(33.3%) patients were severe,8(24.2%) patients were moderate and14(42.4%) patients were mild. The degree of pruritus in patients with history of VVC:5(19.2%) patients were severe,8(30.8%) patients were moderate and13(50%) patients were mild.(2) Patch test positive to at least one concentration of C. albicans recorded as positive. Of the33patients enrolled in the VVC group,18patients (54.5%) were positive. Of the26patients with the history of VVC,13patients (50%) were positive.5patients (17.9%) were positive enrolled in the control group. There were no significant difference in patch-positive rate between patients with VVC and history of WC (χ2=0.120, P=0.728). There were significant difference in patch-positive rate between patient with VVC and the controls (x2=8.681, P=0.003). There were significant difference in patch-positive rate between patient with history of WC and the controls (x2=6.268, P=0.012)(3) Some patients with positive C. albicans patch test result showed an inverse concentration response (stronger patch test reactions were observed in the lower concentration as compared with the higher concentration of C. albicans).(4) No patient reacted to skin prick tests with the commercial preparation of C. albicans.(5) Of33VVC patients,24patients (72.7%) were identified as C. albicans and9patients (27.3%) were identified as non-C. albicans. There were no significant difference in patch-positive rate between patient with C. albicans infection and non-C. albicans infection.(P=1.000)2.4Conclusions(1) Vulvar pruritus women with VVC or history of WC occasionally have frequently react to patch tests for C. albicans. Patch tests to C. albicans may only be effective at low concentrations in order to avoid potential immunosuppressive stimulation observed with higher concentrations of C. albicans. C. albicans hypersensitivity were an important factor in vulvar itching.(2) There were no significant difference in patch-positive rate between patients with C. albicans infection and non-C. albicans infection. So there may have a cross-allergic reactions between C. albicans and non-C. albicans.