What is yeast moist dermatitis in skin folds?

Yeast Moist Dermatitis in Skin Folds (Candidal Intertrigo)

Yeast moist dermatitis in skin folds, clinically termed candidal intertrigo, presents as erythematous, moist, macerated skin with characteristic satellite lesions (small pustules or papules) at the periphery of the main affected area, typically occurring in intertriginous zones where skin-on-skin friction and moisture accumulation create an ideal environment for Candida species overgrowth. 1

Clinical Presentation

The condition manifests with distinct features that differentiate it from other intertriginous dermatoses:

• Primary lesions: Regions of erythema with peripheral scaling in skin folds, often with a moist, macerated appearance 1
• Satellite lesions: The pathognomonic feature consists of small erythematous papules or pustules surrounding the main area of involvement, which is diagnostic for candidal infection 1
• Distribution: Commonly affects natural body folds (axillae, inframammary areas, groin, intergluteal cleft) and obesity-created folds 2
• Associated features: The affected areas may show hyperpigmentation and thickening, with scaling and erythema at the periphery 3

Predisposing Factors

The development of candidal intertrigo requires understanding of contributing elements:

• Moisture and friction: Skin-on-skin contact combined with perspiration, urine, or feces creates the primary environment for fungal proliferation 2, 1
• Lack of ventilation: Occluded skin folds prevent adequate air circulation 1
• Host factors: Obesity, diabetes, immunosuppression, reduced mobility, and bedridden status increase susceptibility 4, 3, 2

Diagnostic Confirmation

Clinical diagnosis based on characteristic satellite lesions is typically sufficient, but confirmation with potassium hydroxide (KOH) preparation should be performed in resistant or atypical cases. 1

• KOH preparation: Skin scraping with KOH examination provides definitive diagnosis by visualizing yeast and pseudohyphae 3, 1
• Culture: Reserved for resistant cases or when identifying specific Candida species is necessary for treatment selection 5
• Microscopic examination: Special fungal stains (periodic acid-Schiff, Grocott's methenamine silver) may be used for histopathologic confirmation when biopsy is performed 4

Differential Considerations

Candidal intertrigo must be distinguished from:

• Bacterial intertrigo: May require bacterial culture or Wood lamp examination to identify Corynebacterium minutissimum (coral-red fluorescence) or streptococcal superinfection 1
• Seborrheic dermatitis: Lacks satellite lesions and has different distribution pattern, though Malassezia yeasts may be involved 6, 7
• Acanthosis nigricans: Shows symmetric hyperpigmentation without the erythema, scaling, or satellite lesions characteristic of fungal infection 3

Treatment Approach

First-line therapy consists of topical antifungals combined with measures to reduce moisture and friction, with systemic therapy reserved for extensive or resistant infections. 5, 4, 3

Topical Antifungal Therapy

• Azole antifungals: Clotrimazole, miconazole, ketoconazole, oxiconazole, or econazole applied to affected areas 5, 1
• Polyene antifungals: Nystatin is effective for localized candidal infections 5, 1
• Duration: Continue treatment until clinical resolution, typically 7-14 days 5

Systemic Therapy Indications

• Oral fluconazole: 100-200 mg daily for 7-14 days for resistant cases or extensive involvement 5, 1
• Disseminated infection: Echinocandins serve as first-line agents for systemic candidiasis 4
• Non-albicans species: Candida glabrata and C. krusei may require alternative therapy such as topical boric acid or flucytosine due to azole resistance 5

Adjunctive Measures

Addressing underlying predisposing factors is essential for treatment success and prevention of recurrence. 4

• Moisture control: Use absorptive powders (cornstarch) or barrier creams to minimize friction 2
• Hygiene: Keep affected areas clean and thoroughly dry, especially after showering or physical activity 2
• Clothing modifications: Wear light, nonconstricting, absorbent clothing; avoid wool and synthetic fibers 2
• Environmental precautions: Minimize exposure to heat and humidity 2

Management of Superinfection

Secondary bacterial infection requires additional treatment:

• Streptococcal superinfection: Topical mupirocin or oral penicillin 1
• Corynebacterium infection: Oral erythromycin 1
• Mixed infections: May require combination antimicrobial therapy based on culture results 1

Common Pitfalls

• Prophylactic antibiotics: Should not be used; reserve antimicrobials for documented infection 5
• Overtreatment: Excessive use of antiseptic creams can irritate skin and worsen the condition 5
• Incomplete drying: Failure to thoroughly dry intertriginous areas before applying topical agents reduces efficacy 2
• Ignoring predisposing factors: Treatment of infection alone without addressing moisture, friction, and underlying conditions leads to recurrence 4, 2