Carbuncle

A carbuncle is an acute suppurative-necrotic inflammation that affects a group of adjacent hair follicles and sebaceous glands. The lesion is characterized by a large, deep inflammatory infiltrate in the skin and fatty layer of the subcutaneous tissue, followed by necrosis and sloughing of tissue.

By its nature, a carbuncle represents a more severe and extensive form of a furuncle (boil). Unlike a furuncle, which has a single purulent core, a carbuncle develops multiple purulent-necrotic foci that merge into a single conglomerate.

Etiology and pathophysiology

The most common causative agent is Staphylococcus aureus. The infection penetrates several adjacent hair follicles, producing diffuse inflammation. The process rapidly spreads both in scope and depth, involving the dermis and fatty layer of the subcutaneous tissue.

Pathophysiologically, carbuncles are characterized by thrombosis of the vessels supplying the affected area, which leads to extensive tissue necrosis. In the center of the infiltrate, multiple openings form, through which thick, greenish pus is discharged.

Clinical Significance

A carbuncle appears as a large, firm, extremely painful, dark red to bluish infiltrate. It is accompanied by pronounced systemic symptoms of intoxication, including high fever, chills, and weakness. The most dangerous localization is on the face (upper lip, nose) due to the risk of infection spreading into the cranial cavity, that may cause cavernous sinus thrombosis.

Unlike most furuncles, carbuncles are typically treated surgically. A wide cruciform incision of the infiltrate is made, all necrotic tissue is excised, and adequate drainage is ensured. Surgery must be supplemented with systemic antibiotic therapy. Attempts at self-extraction or squeezing are strictly prohibited due to the high risk of infection spread.