A carbuncle is a cluster of boils caused by bacterial infection, most commonly with Staphylococcus aureus or Streptococcus pyogenes.

[2] The infection is contagious and may spread to other areas of the body, or other people; those living in the same residence may develop carbuncles at the same time.

[4] A carbuncle is a cluster of several boils, which is typically filled with purulent exudate (dead neutrophils, phagocytized bacteria, and other cellular components).

[5] Fluid may drain freely from the carbuncle, or intervention involving an incision and drainage procedure may be needed.

Sometimes more severe symptoms may occur, such as fatigue, fever, chills, and general malaise as the body fights the infection.