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Candidiasis (Mucocutaneous)



Denise M. Aaron

, MD, Dartmouth Geisel School of Medicine

Reviewed/Revised Sep 2023
Topic Resources

Candidiasis is skin and mucous membrane infection with Candida species, most commonly Candida albicans. Infections can occur anywhere and are most common in skinfolds, digital web spaces, genitals, cuticles, and oral mucosa. Symptoms and signs vary by site. Diagnosis is by clinical appearance and/or potassium hydroxide wet mount of skin scrapings. Treatment is with drying agents and antifungals.

Most candidal infections are of the skin and mucous membranes, but invasive candidiasis is common among patients who are immunosuppressed and can be life threatening.

Etiology of Mucocutaneous Candidiasis

Potentially pathogenic fungi include dermatophytes Overview of Dermatophytoses Dermatophytoses are fungal infections of keratin in the skin and nails (nail infection is called tinea unguium or onychomycosis). Symptoms and signs vary by site of infection. Diagnosis is by... read more 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 Acute Paronychia 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 Onychomycosis ). In people with obesity, 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).

Symptoms and Signs of Mucocutaneous Candidiasis

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.

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 Acute Paronychia , 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 Onycholysis ), with white or yellow discoloration of the subungual area.

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

  • Clinical appearance

  • Potassium hydroxide wet mounts

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.

Treatment of Mucocutaneous Candidiasis

  • Sometimes drying agents

  • Topical or oral antifungals

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 ). Powdered formulations are also helpful (eg, miconazole powder 2 times a day for 2 to 3 weeks). Fluconazole 150 mg orally once a week for 2 to 4 weeks can be used for extensive intertriginous candidiasis; topical antifungals 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.

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. A systemic antifungal may also be used (eg, oral fluconazole).

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

Key Points

  • Candida are normal skin flora that can become infective under certain conditions (eg, excessive moisture, alteration of normal flora, host immunosuppression).

  • Consider candidiasis with erythematous, scaling, pruritic patches in intertriginous areas and with lesions in the mucous membranes, around the nails, or at the corners of the mouth.

  • If clinical appearance is not diagnostic, try to identify yeast and pseudohyphae in potassium hydroxide wet mounts of scrapings from a lesion.

  • Treat most intertriginous candidiasis with a drying agent and a topical antifungal.

  • Treat most diaper rash with frequent changes of absorbent disposable diapers and an imidazole cream.

  • Treat oral candidiasis with clotrimazole troches, nystatin oral suspension, or an oral antifungal.

Drugs Mentioned In This Article

Drug Name Select Trade
Aloe Vesta, Antifungal, AZOLEN TINCTURE, Baza, Cruex, Desenex, Desenex Jock Itch, Fungoid, Lotrimin AF, Lotrimin AF Antifungal Liquid, Lotrimin AF Deodorant, Lotrimin AF Powder, Lotrimin AF Spray, Micaderm , Micatin, Miconazole 7, Micotrin AP, Micro-Guard , Mitrazol, Monistat 1 Day or Night Combination Pack, Monistat 1 Vaginal Ovule Combination Pack, Monistat 1 Vaginal Ovule Combination Pack (Prefilled), Monistat 3, Monistat 3 Vaginal Cream (Prefilled), Monistat 3 Vaginal Cream Combination Pack, Monistat 3 Vaginal Cream Combination Pack (Prefilled), Monistat 3 Vaginal Ovule Combination Pack, Monistat 3 Vaginal Suppositories Combination Pack, Monistat 7, Monistat 7 Vaginal Cream Combination Pack, Monistat-Derm, Mycozyl AP, Neosporin AF, Novana Anti-Fungal, Oravig, Remedy, Soothe & Cool INZO, Ting Antifungal, Triple Paste AF , Vagistat-3, Zeasorb Athlete's Foot, Zeasorb Jock Itch
Bio-Statin , Mycostatin, Nyamyc, Nyata, Nystex, Nystop, Pedi-Dri
Alevazol , Antifungal, Anti-Fungal, Cruex, Desenex, Fungoid, Gyne-Lotrimin, Lotrimin, Lotrimin AF, Lotrimin AF Ringworm, Micotrin AC, Mycelex, Mycelex Troche, Mycozyl AC
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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