Diagnosis
Great, big, tender, zits. There is a histologic difference between a carbuncle and a furuncle and I do not care.
Epidemiologic Risks
Scratching yourself after picking your (but not anothers) nose (the anterior nares is where S. aureus tends to be carried.
And for eyebrow infection, that are mostly MRSA, the risks are "eyebrow hair removal (tweezing, waxing, threading, or shaving) in 17 cases (21.3%), manipulation of acne lesions ("popping," "picking," or "squeezing") in 6 cases (7.5%), and both brow hair removal and acne manipulation in 1 case (1.3%)." (PubMed) according to the people at the quaintly named and very subspecialized Massachusetts Eye and Ear Infirmary.
And the occasional carbuncle is found in a goose (PubMed).
Microbiology
Empiric Therapy
I&D is the most effective therapy.
Treat for S. aureus, usually for 10 days. Antibiotics probably do more to prevent recurrence than hasten resolution (PubMed).
And do not just suck out the pus with a needle, compared to an I&D, 74% of needle aspiration FAILED vs 20% of open I&D (PubMed).
Pearls
Recurrent staph infections (cellulitis, folliculitis, carbuncles) can be treated with the following:
2 weeks po antistaph antibiotics PLUS
Mupirocin in the nose for 2 weeks PLUS
Hibiclens showers for 2 weeks PLUS
terminal cleaning of the house: hot water bleach the sheets, towels and anything else that gets wet and reused. New makeup, flip the mattress, new pillows.
If the patient, their family or pet has any chronic skin conditions (atopic dermatitis, psoriasis, eczema) trying to get rid of staph will be as successful as getting democracy in Iraq (written in December 2005; a comment for which I was reported to the Chair of Medicine at one of my hospitals). Patients with those skin conditions are ALWAYS covered in S. aureus
I tend to think of humans more like (Pig Pen), from the comic strip Peanuts, in a cloud of skin and bacteria.
Rants
I read somewhere recently (in other words I cannot find the reference) that if your pillow is 5 years old by weight it is 20% skin, mites and bacteria. More people have bought new pillows after I have told them that).
Last Update: 05/27/18.