Porth's Essentials of Pathophysiology, 4e

1054

Genitourinary and Reproductive Function

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however, candidiasis requires a favorable environment for growth of the organism. Studies have documented the presence of Candida on the penis of male partners of women with vulvovaginal candidiasis, but few men develop balanoposthitis that requires treatment. 18 The gastrointestinal tract also serves as a reservoir for this organism, and candidiasis can develop through autoin- oculation in women who are not sexually active. Reported risk factors for the overgrowth of C. albicans include recent antibiotic therapy, which suppresses the normal protective bacterial flora; high hormone levels owing to pregnancy or the use of oral contraceptives, which cause an increase in vaginal glycogen stores; and uncontrolled diabetes mellitus, HIV infection, or other diseases, which compromise the immune system. 16–18 Women with vulvovaginal candidiasis commonly com- plain of vulvovaginal pruritus accompanied by irrita- tion, erythema, swelling, dysuria, and dyspareunia. The characteristic discharge, when present, is usually thick, white, and odorless. In obese persons, Candida may grow in skin folds underneath the breast tissue, the abdominal flap, and the inguinal folds. Accurate diagnosis ismade by identification of budding yeast filaments (i.e., hyphae) or spores on a wet-mount slide using 10% potassium hydroxide (Fig. 41-3A). The pH of the discharge, which is checked with litmus paper, typically is less than 4.5. When the wet-mount technique is negative but the clinical manifestations are suggestive of candidiasis, a culture may be necessary. For treatment purposes, vulvovaginitis is commonly classified as uncomplicated or complicated. Current choice of therapeutic agents is for the most part limited to the azole medications, fungistatic drugs that inhibit cell wall metabolism. Some of these antifungal medica- tions (e.g., clotrimazole, micronazole) are available as topical preparations (creams or suppositories) that can be obtained without a prescription for treatment in women with uncomplicated cases of candidiasis. Topical terconazole and oral fluconazole are also available with prescription. Because of ease of use, oral fluconazole has become a preferred method for most women, but

SUMMARY CONCEPTS (continued)

Vaginal Infections Candidiasis, trichomoniasis, and bacterial vaginosis are vaginal infections that can be associated with sexual activity. Trichomoniasis is the only form of vaginitis that is known to be sexually transmitted and requires part- ner treatment. A male partner usually is asymptomatic. Candidiasis Vulvovaginal candidiasis, also referred to as a yeast infec­ tion , thrush , or moniliasis , is one of the most frequent reasons that women visit a health care provider. Candida albicans is the most commonly identified organism in vaginal yeast infections, but other Candida species, such as Candida glabrata and Candida tropicalis , may also be present. 16–18 These organisms are present in 20% to 55% of healthy women without causing symptoms, and alteration of the host vaginal environment usually is necessary before the organism can cause pathologic effects. 18 Although vulvovaginal candidiasis usually is not transmitted sexually, it is included in the CDC STI treatment guidelines because it often is diagnosed in women being evaluated for STIs. The possibility of sex- ual transmission has been recognized for many years; ■■ Genital warts (condylomata acuminata) are caused by the human papillomavirus (HPV) that infects epithelial cells. Of particular concern is the relation between HPV infections and the development of genital neoplasms. Over 100 types of HPV have been identified, including subtypes 6 and 11, which are typically associated with genital warts, and subtypes 16 and 18, which account for approximately two thirds of cervical dysplasia and cervical cancer. ■■ Genital herpes is an ulcerative disorder caused by the highly contagious herpes simplex virus (HSV). Both HSV-1 and HSV-2 are neurotrophic viruses that produce acute primary infections and latent recurrent episodes. During the primary infection, the HSV ascends through peripheral nerves to a sacral dorsal root ganglia. Recurrences occur when the virus is reactivated and travels down the nerve root to the affected area.There is no permanent cure for herpes infections. ■■ Chancroid and lymphogranuloma venereum (LGV) produce external genital lesions with various degrees of inguinal lymph node involvement.These diseases are uncommon in the United States.

A

C

B

FIGURE 41-3. Organisms that cause vaginal infections. (A) Candida albicans (blastospores and pseudohyphae); (B,C) Trichomonas vaginalis.