What is furuncle/Boil?

Acute, round, tender, circumscribed perifollicular abscess generally ends in central suppuration, deep necrotic folliculitis, S.aureus [maybe recurrent if resistant, painful papule/nodule centered by pustule and central necrosis] differential (fungal [candida, dermatophytes], pseudofolliculitis [no pathogen, body rxn, Crohn's disease/eosinophilic folliculitis], Hidradenitis suppurativa (Verneuil's disease): chronicinflammation of the pilosebaceous follicles and sweat glands in areas rich in apocrine glands (axillary, sub- mammary and anoperineal folds), Epidermal inflammatory cyst or superinfected cyst: Preexisting cyst (face)