First-ever guideline for skin infections reevaluated

September 12, 2005

The first-ever guideline for the treatment of uncomplicated skin infections, produced in January of this year by a panel of six physicians with funding by Abbott Laboratories, is undergoing major revisions and may result in the production of several other algorithms for treatment by other medical specialists. So reported speakers at an Abbott-sponsored symposium in conjunction with the recent annual meeting of the American Academy of Dermatology (AAD) in Chicago.

The first-ever guideline for the treatment of uncomplicated skin infections, produced in January of this year by a panel of six physicians with funding by Abbott Laboratories, is undergoing major revisions and may result in the production of several other algorithms for treatment by other medical specialists. So reported speakers at an Abbott-sponsored symposium in conjunction with the recent annual meeting of the American Academy of Dermatology (AAD) in Chicago.

The first draft of the algorithm, "The Management of Uncomplicated Skin and Skin Infections: A Treatment Algorithm," was a "good effort," but there were adjustments to the original algorithm, said Dirk M. Elston, M.D., associate physician, dermatology department, at Geisinger Medical Center. He is also a member of Abbott's advisory board and one of the physicians who initially designed the guideline. "The original draft was geared toward primary care physicians" and could be interpreted to suggest that treatment for uncomplicated skin infections should begin before a diagnosis is made. "Incision and drainage should be front and center when the patient presents with an abscess. In such cases, surgery might be more important than the choice of antibiotics."

Despite some other changes, the algorithm continues to emphasize the use of cephalosporins in uncomplicated skin infections. The AAD may be producing its own treatment guideline for uncomplicated skin infections, and a number of drugs in the dermatologic arena are expected to go off patent shortly. Speakers at the symposium agreed that cephalosporins are a favorable remedy for uncomplicated skin infections-at least for the time being and especially in light of growing resistance to other drugs among microorganisms.

Some concern with the cephalosporin option involved possible cross-reactivity on the part of those with a penicillin allergy, according to some speakers. Ted Rosen, M.D., chief of dermatology at Houston VA Medical Center and professor in the department of dermatology at Baylor College of Medicine, said, "True increased risk with penicillin allergy may relate to a primary allergy to cephalosporin." Rosen is also on Abbott's speakers' bureau. But, he noted, penicillin-allergic patients have a threefold increased reaction to any medicine. While noting that third-generation cephalosporins offered good gram-negative protection, but not as much protection against gram-positive microorganisms, he pointed out that extended-spectrum drugs such as cefdinir offer broad coverage against both sorts.

Historically, the reported rate of cephalosporin reaction in penicillin-allergic patients has been given at 7%-8.1%, Rosen said. However, he added that true cross-reactivity rates are related to which side-chains are present in the form of cephalosporin being prescribed.

Of the two relevant drugs going off patent, Cefzil (cefprozil, Bristol-Myers Squibb) is a cephalosporin and Zithromax (azithromycin, Pfizer) is a macrolide mentioned by name in the first draft of the guidelines as an alternative antibiotic therapy. (Macrolides are also mentioned as an alternative therapy in the revised version.) Cefprozil is described as a second-generation cephalosporin, and, though it may soon be available in a generic format, sources at the symposium argued that Abbott's cefdinir has the advantage of broader coverage. In addition, cefdinir is available in five- or 10-day dosing for adults and in 125- or 250-mg dosing for children, making improved compliance possible, it was emphasized.

Some of the physicians who produced the first draft of the guidelines noted that azithromycin, the macrolide that may go generic, offered similar clinical success rates and tolerability as certain cephalosporins. Another possible option, the fluoroquinolone levofloxacin (Levaquin, Ortho-McNeil), was listed as a possible alternative therapy in the first draft, but the initial framers expressed concerns about resistance among other factors and the class was dropped from the second draft.

Bacterial resistance was a major factor in constructing the guidelines, said some of the physicians present. Work is ongoing on a methicillin-resistant Staphylococcus aureus-cephalosporin now in the pipeline, according to Elston. Other forthcoming algorithms, he said, are likely to feature the podiatric, dermatologic, and surgical-prophylactic settings.

The author is a writer based in Chicago.