“Fake news!” All you need for effective treatment for abscesses is an incision and drainage procedure – adjunctive antibiotics are just unnecessary exposures with only marginal benefit, at best.
Then, unfortunately, two trials have been published in the New England Journal of Medicine showing benefit for antibiotics – either trimethoprim-sulfamethoxazole or clindamycin – improve the rate of clinical cure. The magnitude of benefit was somewhere in the range of a number needed to treat between 7 and 14, with infrequent harms, suggesting the balance of benefit may favor antibiotics. However, the abscesses included in these study tended to be large, suggesting perhaps these results weren’t easily generalizable.
This is a subgroup analysis of one of these two studies, trying to dredge out a specific population for whom antibiotics weren’t actually of value. And, unfortunately, for the purists among us, the results are bleak. Accounting for the diminishing statistical power and reliability of such an analysis, there are few useful signals within these data. Neither the size of the abscess nor the area of surrounding erythema reliably predicted diminishing returns from adjunctive antibiotics, nor did presence of fever or comorbid illness. The only probably reliable signal in these data, consistent with results in the era prior to MRSA, shows antibiotics are probably unnecessary for those who are not infected with staphylococci. Unfortunately, until that point where the causative agent can be easily ascertained at the time of I&D procedure, these data aren’t terribly useful in a practical sense.
So, the benefit is not universal, but it’s nothing at which to scoff. Perhaps a delayed antibiotic strategy could be considered, but, it seems most patients ought be offered antibiotics following drainage of a clinically significant abscess.
“Subgroup Analysis of Antibiotic Treatment for Skin Abscesses”