Cutaneous and mucocutaneous candidiasis !

A yeast infection of warm, moist skin folds or of the mouth, giving red, itchy patches with small satellite spots or white plaques that scrape off.

Updated 2026-11-01

Structures involved

Tap one to see what it is and open it in 3D.

Why it happens

What it is

Infection of the skin, nails or mucous membranes by Candida yeasts, mainly Candida albicans, which normally live on the body in small numbers. Common forms are intertrigo in skin folds, oral thrush, candidal diaper rash, angular cheilitis and paronychia. Vulvovaginal candidiasis has its own page.

Who gets it

Very common worldwide. Oral thrush is frequent in newborns, denture wearers and people with HIV or on inhaled corticosteroids; intertrigo is common in people with obesity or diabetes. The hot, humid climate of much of Colombia and Latin America favours skin-fold infection, and oral or oesophageal candidiasis remains a frequent sign of advanced HIV infection in the region.

Causes

Candida albicans in most cases; other species (C. glabrata, C. tropicalis, C. parapsilosis) less often
Overgrowth of normal flora when local moisture, heat or friction increase
Loss of competing bacteria after broad-spectrum antibiotics
Weakened cellular immunity (HIV, corticosteroids, chemotherapy)

Risk factors

Obesity and deep skin folds; tight, occlusive clothing
Diabetes mellitus, especially when poorly controlled
Infancy (thrush and diaper area) and old age
Recent antibiotics, systemic or inhaled corticosteroids
HIV infection, cancer treatment or other immunosuppression
Dentures, dry mouth and frequent wet work (hands)

Pathophysiology

Candida switches from a harmless yeast form to an invasive hyphal form when the local environment is warm, wet and macerated or when host defences are weak. Hyphae adhere to and penetrate the stratum corneum or mucosal epithelium and trigger a neutrophil-rich inflammation. Cell-mediated immunity (T-helper 17 responses) normally keeps the yeast in check, which is why defects of T-cell function lead to oral, oesophageal and chronic mucocutaneous disease.

Classification

Intertrigo: groin, under the breasts, armpits, abdominal and gluteal folds
Oral candidiasis: pseudomembranous (thrush), erythematous (atrophic), angular cheilitis
Candidal diaper dermatitis
Candidal paronychia and onychomycosis; interdigital infection (erosio interdigitalis)
Chronic mucocutaneous candidiasis (rare, linked to inherited immune defects)

Symptoms and signs

Bright red, moist, shiny patches in skin folds with a scalloped edge
Small red papules and pustules beyond the edge (satellite lesions)
Itching, burning or soreness, worse with sweating
White, curd-like plaques on the tongue, palate or cheeks that scrape off and leave a red, sometimes bleeding base
Painful cracks at the corners of the mouth; red, swollen nail folds

Diagnosis

Clinical: Usually clinical: a red, macerated rash in a fold with satellite lesions, or white plaques that wipe off the oral mucosa.
Tests: Potassium hydroxide (KOH) preparation of a scraping shows budding yeasts and pseudohyphae; culture identifies the species and helps in resistant or recurrent cases. Blood glucose or HbA1c and HIV testing when the cause is unclear or infection recurs.
Imaging: Not needed for skin or oral disease. Endoscopy if oesophageal involvement is suspected and does not respond to empirical treatment.

Differential diagnosis

Dermatophyte infection (tinea cruris): sharp scaly edge, central clearing, no satellite lesions
Inverse psoriasis
Seborrhoeic dermatitis
Erythrasma (Corynebacterium; coral-red fluorescence under Wood's lamp)
Oral leukoplakia or lichen planus (white plaques that do not scrape off)

Goal of treatment

Clear the yeast, relieve symptoms and correct the conditions that let Candida overgrow, such as moisture, hyperglycaemia or immunosuppression.

Treatment

Medical: Skin and folds: topical azoles (e.g. clotrimazole, miconazole) or nystatin; a short course of a mild topical corticosteroid may be added for marked inflammation.
Medical: Oral thrush: topical nystatin suspension or miconazole; oral fluconazole for moderate to severe disease, immunosuppressed patients or oesophageal involvement.
Conservative: Keep folds clean and dry, use absorbent cotton or barrier layers between folds, loose clothing; denture hygiene and removal at night; rinse the mouth after inhaled corticosteroids.
Follow-up: Control blood glucose, review antibiotic and corticosteroid use, and investigate recurrent cases for diabetes or HIV.

Drugs for this condition

Complications

Recurrence when predisposing factors persist
Secondary bacterial infection of macerated skin
Oesophageal candidiasis in immunosuppressed patients
Invasive candidiasis or candidaemia in critically ill or neutropenic patients
Nail dystrophy after chronic paronychia

Prognosis

Skin and oral infection respond well to treatment within one to two weeks, but often come back unless moisture, diabetes or immunosuppression are addressed.

Prevention

Keep skin folds dry; weight control in obesity
Good glycaemic control in diabetes
Avoid unnecessary antibiotics
Mouth rinsing after inhaled corticosteroids and proper denture care

Test yourself

Think of the answer, then tap the question to see it.

Which finding helps distinguish candidal intertrigo from tinea cruris?

Satellite papules and pustules beyond the edge of a bright red, moist patch; tinea has a scaly advancing border with central clearing.

What does a KOH preparation show in candidiasis?

Budding yeasts with pseudohyphae.

How are the white plaques of oral thrush distinguished from leukoplakia?

Thrush plaques scrape off, leaving a red base; leukoplakia does not scrape off.

Which test should be considered in an adult with unexplained thrush?

HIV testing (and blood glucose for diabetes).

What is a nursing measure for a patient using an inhaled corticosteroid to prevent thrush?

Teach rinsing the mouth and spitting after each use.

Add to my cards (5)

Educational information, not medical advice. For any symptom, see a health professional.

Sources: Candida infection of the skin (MedlinePlus, US National Library of Medicine, 2026); Thrush - children and adults (MedlinePlus, US National Library of Medicine, 2026).

← All conditions

Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake

Representative model, for educational purposes only.

Skin highlighted on the Durgical 3D model