Furuncles (ie, boils) are single hair follicle-associated inflammatory nodules extending into the dermis and the subcutaneous tissue, usually affecting moist, hairy, friction-prone areas of the body, such as the face, axillae, neck, and buttocks. Firm and tender, these nodular erythematous lesions may spontaneously drain purulent material. Fever and other constitutional symptoms rarely are present. The most common causative microorganism is S aureus, but the microbiology of furuncles depends on the location of the lesions. Risk factors for developing this condition include obesity, diabetes mellitus, atopic dermatitis, parenteral drug use, chronic kidney disease, impaired neutrophil function, use of corticosteroids, close exposure to others who have furuncles (ie, family members, contact sports), and malnutrition [8-11]. When the subcutaneous infection extends to involve multiple furuncles, the lesions are called carbuncles. Carbuncles are often located in the back of the neck, posterior trunk, or thigh. This multiseptate coalescence of multiple abscesses can be painful, and constitutional signs and symptoms, including fever and malaise, often are present. Purulent material may be expressed from multiple draining sinuses.
Severe complications of furuncular infections, such as bacterial endocarditis, have been reported . If systemic involvement of any type is suspected, evaluation should include a complete blood count, blood cultures, and Gram stain and culture of purulent material. Small-sized furuncles usually can be managed by applying moist heat to encourage drainage. Incision and drainage is needed for carbuncles and larger furuncles . Systemic antibiotics usually are reserved for individuals who have systemic signs of infection or associated cellulitis. Surgical consultation often is recommended for patients who have carbuncles.
Recently, a prospective study from 11 university-affiliated emergency departments reported an overall prevalence of MRSA in 59% of 422 patients who presented acutely with purulent skin and soft tissue infections . This finding dictates a consideration of empiric coverage of MRSA in these infections in addition to incision and drainage when antibiotics are indicated . Typically these S aureus isolates contain the PVL (Panton-Valentine Leuko-cidin) gene, exhibit a single pulsed-field electrophoretic pattern, and possess a type IV SCCmec element that confers methicillin resistance [14,15]. Patients who have recurrent furuncles may require eradication of S aureus from the nares with agents such as mupirocin ointment or oral clindamycin to decrease risk for infection .
Was this article helpful?