Candidiasis (Mucocutaneous)

Potentially pathogenic fungi include dermatophytes and yeast. Candida is a group of about 150 yeast species. C. albicans is responsible for about 70 to 80% of all candidal infections. Other significant species include C. glabrata, C. tropicalis, C. krusei, and C. dubliniensis.

Candida is a ubiquitous yeast that resides harmlessly on skin and mucous membranes until dampness, heat, and impaired local and systemic defenses provide a fertile environment for it to grow.

Risk factors for candidiasis include

Candidiasis occurs most commonly in intertriginous areas such as the axillae, groin, and gluteal folds (eg, diaper rash), in digital web spaces, on the glans penis, and beneath the breasts. Vulvovaginal candidiasis is common among women. Candidal nail infections and paronychia Acute Paronychia Paronychia is infection of the periungual tissues. Acute paronychia causes redness, warmth, and pain along the nail margin. Diagnosis is by inspection. Treatment is with antistaphylococcal antibiotics... read more may develop after improperly done manicures and in kitchen workers and others whose hands are continually exposed to water ( see Onychomycosis Onychomycosis Onychomycosis is fungal infection of the nail plate, nail bed, or both. The nails typically are deformed and discolored white or yellow. Diagnosis is by appearance, wet mount, culture, polymerase... read more ). In obese people, candidal infections may occur beneath the pannus (abdominal fold). Oropharyngeal candidiasis is a common sign of local or systemic immunosuppression.

Chronic mucocutaneous candidiasis typically affects the nails, skin, and oropharynx. Patients have cutaneous anergy to Candida, absent proliferative responses to Candida antigen (but normal proliferative responses to mitogens), and an intact antibody response to Candida and other antigens. They also have impaired T-cell–mediated immunity. Chronic mucocutaneous candidiasis may occur as an autosomal recessive illness associated with hypoparathyroidism and Addison disease (Candida-endocrinopathy syndrome).

Intertriginous infections manifest as pruritic, well-demarcated, erythematous patches of varying size and shape; erythema may be difficult to detect in darker-skinned patients. Primary patches may have adjacent satellite papules and pustules.

Perianal candidiasis produces white maceration and pruritus ani.

Vulvovaginal candidiasis causes pruritus and discharge ( see Candidal Vaginitis Candidal Vaginitis Candidal vaginitis is vaginal infection with Candida species, usually C. albicans. Symptoms are usually a thick, white vaginal discharge and vulvovaginal pruritus that is often... read more ).

Candidal nail infections can affect the nail plate, edges of the nail, or both. Candidal infection is a frequent cause of chronic paronychia Acute Paronychia Paronychia is infection of the periungual tissues. Acute paronychia causes redness, warmth, and pain along the nail margin. Diagnosis is by inspection. Treatment is with antistaphylococcal antibiotics... read more , which manifests as painful red periungual swelling. Subungual infections are characterized by distal separation of one or several fingernails (onycholysis Onycholysis Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are... read more ), with white or yellow discoloration of the subungual area.

Oropharyngeal candidiasis causes white plaques on oral mucous membranes that may bleed when scraped (see Interpretation of findings Interpretation of findings Oral inflammation and ulcers, known as stomatitis, may be mild and localized or severe and widespread. They are invariably painful. (See also Evaluation of the Dental Patient and Gingivitis... read more ).

Perlèche is candidiasis at the corners of the mouth, which causes cracks and tiny fissures. It may stem from chronic lip licking, thumb sucking, ill-fitting dentures, or other conditions that make the corners of the mouth moist enough that yeast can grow.

Chronic mucocutaneous candidiasis is characterized by red, pustular, crusted, and thickened plaques resembling psoriasis, especially on the nose and forehead, and is invariably associated with chronic oral candidiasis.

Diagnosis of mucocutaneous candidiasis is based on clinical appearance and identification of yeast and pseudohyphae in potassium hydroxide wet mounts of scrapings from a lesion. Positive culture alone is usually meaningless because Candida is omnipresent.

Intertriginous infection is treated with drying agents as needed (eg, Burow solution compresses applied for 15 to 20 minutes for oozing lesions) and topical antifungals ( see Table: Options for Treatment of Superficial Fungal Infections* Options for Treatment of Superficial Fungal Infections* ). Powdered formulations are also helpful (eg, miconazole powder 2 times a day for 2 to 3 weeks). Fluconazole 150 mg orally once/week for 2 to 4 weeks can be used for extensive intertriginous candidiasis; topical antifungal agents may be used at the same time.

Candidal diaper rash is treated with more frequent changes of diapers, use of super- or ultra-absorbent disposable diapers, and an imidazole cream 2 times a day. Oral nystatin is an option for infants with coexisting oropharyngeal candidiasis; 1 mL of suspension (100,000 units/mL) is placed in each buccal pouch 4 times a day.

Candidal paronychia is treated by protecting the area from wetness and giving topical or oral antifungals. These infections are often resistant to treatment. Thymol 4% in alcohol applied to the affected area 2 times a day is often helpful.

Oral candidiasis can be treated by dissolving 1 clotrimazole 10-mg troche in the mouth 4 to 5 times a day for 14 days. Another option is nystatin oral suspension (4 to 6 mL of a 100,000 unit/mL solution) held in the mouth for as long as possible and then swallowed or expectorated 3 to 4 times a day, continuing for 7 to 14 days after symptoms and signs have resolved. A systemic antifungal may also be used (eg, fluconazole 200 mg orally on the first day, then 100 mg orally once a day for 2 to 3 weeks thereafter).

Chronic mucocutaneous candidiasis requires long-term oral antifungal treatment with oral fluconazole.