Abscesses

Follicular pyodermas (furuncles, carbuncles)

Chronic fungal infection (cutaneous blastomycosis, actinomycosis)

Tuberculosis or other mycobacterial infection

Granuloma inguinale

Lymphogranuloma venereum

Acne vulgaris/acne conglobata

Inflamed/ ruptured epidermal cyst

Pilonidal cyst

Metastatic Crohn disease

Pyoderma gangrenosum