Red, Oily, Smelly Skin Folds: Intertrigo and Differential Diagnosis

Top Diagnoses for Intertriginous Rash

Condition	Key Features	First-Line Treatment
Intertrigo (irritant + 2° infection)	Symmetrical, moist, erythematous, macerated; skin folds (axillae, inframammary, groin, abdominal pannus)	Dryness, barrier cream (zinc oxide), topical antifungal + mild steroid (e.g., clotrimazole 1% + hydrocortisone 1%)
Candidiasis	Beefy red, satellite pustules, intense itch, +KOH	Topical nystatin, clotrimazole, or oral fluconazole if extensive
Erythrasma	Brownish-red, finely scaling, coral-red fluorescence (Wood's lamp); Corynebacterium minutissimum	Topical/oral erythromycin, clarithromycin; antibacterial wash
Tinea cruris/corporis	Annular, active border, central clearing; dermatophyte +KOH	Topical terbinafine/naftifine; oral if extensive
Inverse psoriasis	Well-demarcated, glazed red plaques (no scale); flexural; ± nail/palp changes	Low-potency steroid, calcineurin inhibitor, vitamin D analog
Seborrheic dermatitis	Yellowish greasy scale; sebaceous areas; Malassezia	Antifungal shampoo/cream, low-potency steroid
Hidradenitis suppurativa	Recurrent nodules, abscesses, sinus tracts, scarring; axillae, groin, inframammary	Topical clindamycin, oral antibiotics, biologics (adalimumab)

General Measures

• Weight loss (reduces fold depth).
• Breathable fabrics, loose clothing.
• Antiperspirant to folds (off-label).
• Keep area dry (hair dryer cool setting).

See dermatologist if unresponsive to 2 weeks OTC therapy or diagnostic uncertainty.