Furuncles and Carbuncles
Subsequent to folliculitis, an inflammatory skin infection called furunculosis may appear at the site of hair follicles. Carbuncles are series of abscesses in the subcutaneous tissue that drain via hair follicles and are a complication of furunculosis. Frequently developing on the back of the neck, face, axillae and buttocks, furuncles and carbuncles are caused by perspiration, friction and bacteria.
People who are obese, on corticosteroid therapy, or those with defective white blood cell function may be predisposed to furuncles and carbuncles. Being in close contact with others who have furunculosis—such as members of a family, military personnel, team athletes, and prison inmates—may increase the likelihood of infection; furuncle outbreaks have been reported in these settings. Staphylococcus aureus is most commonly associated with both infections.
Clinical Features
Local
- Nodular lesions that drain pus spontaneously
Systemic (Carbuncles)
- Fever, which may reflect a deeper infection
Diagnosis
In addition to evaluating the appearance of the skin, bacterial cultures are conducted to determine the infecting microbe.
Treatment
Furuncles and carbuncles may be treated with warm compresses, which promote spontaneous drainage, as well as oral and topical antibiotics. These can include clindamycin, dicloxacillin, cephalexin, doxycycline, minocycline, trimethoprim-sulfamethoxazole and parenteral vancomycin. In some cases, surgical drainage is necessary. Because of an increase in cases of both nosocomial and community-acquired methicillin-resistant S aureus (CA-MRSA), it is important to determine the infecting microbe. During an outbreak, patients are advised to practice good hygiene, wash with a chlorhexidine solution, vigilantly launder clothing and bedsheets, and dress wounds carefully. In the case of recurring furunculosis, mupirocin may be applied to the anterior nares (in patients who carry S aureus nasally), vitamin C or low-dose clindamycin may be prescribed.
