Quick tips: Dermatologists offer assorted array of practical pearls

Las Vegas - Implementing a few simple ideas in clinical practice can have a significant impact in terms of saving time, saving money or improving patient outcomes. During a session at the 2011 Fall Clinical Dermatology Conference, members of the faculty offered a few personal pearls, each so easy and straightforward they could be encapsulated in a one-minute description.

Daniel Siegel, M.D., M.S., clinical professor of dermatology, State University of New York at Downstate, Brooklyn, says that when a surgical wound won’t stop bleeding, a pour-and-press powder (WoundSeal, Biolife) is his go-to solution.

Daniel Siegel, M.D., M.S.

The product comes in single-use packets and consists of a nontoxic hydrophilic polymer and potassium ferrate. When poured onto a bleeding wound, it creates an occlusive seal that stays in place and can function as a dressing until the area heals, he says.

An over-the-counter product also provided the solution to another challenging situation Dr. Siegel described that involved a patient complaining of intermittent severe pruritus of his instep. According to the patient, the itching worsened at bedtime and was more intense on the right foot than the left. There were no visible skin changes and multiple KOH preps were negative.

Dr. Siegel says he consulted itch expert Jeff Bernhard, M.D., who suggested the diagnosis of bilateral isolated sensory peripheral neuropathy of the medial plantar nerves and recommended topical capsaicin cream (Zostrix, Hi Tech Pharmacal). The itching resolved within two days of starting twice daily treatment, recurred within two days after stopping the capsaicin cream, and improved immediately when the medication was restarted.

Toxin tips
Mark Nestor, M.D., Ph.D., voluntary associate professor, department of dermatology and cutaneous surgery, University of Miami Miller School of Medicine, offered a series of tips for using multiple botulinum toxins in clinical practice. He recommends reconstituting with nonpreserved normal saline, as there is some evidence benzyl alcohol, found in bacteriostatic saline, may affect toxin activity.

Dr. Nestor also says that dermatologists using abobotulinumtoxinA (Dysport, Medicis), onabotulinumtoxinA (Botox, Allergan) and incobotulinimtoxinA (Xeomin, Merz) can avoid inadvertent dosing errors by selecting diluent volumes so that equivalent volumes of the reconstituted products contain equivalent doses. For example, assuming a 2.5:1 unit conversion between abobotulinumtoxinA and onabotulinumtoxinA, 20 percent more normal saline will be added to the 300 U vial of abobotulinumtoxinA than to the 100 U vial of onabotulinumtoxinA.

For example, if 2.0 mL is used to reconstitute onabotulinumtoxinA, 2.4 mL of diluent would be added to abobotulinumtoxinA to achieve a 2.5:1 ratio and use of equivalent volumes for injection, he says. “Then, even if the staff hands the doctor the wrong toxin, the dose is equivalent.”

To inject the toxin, Dr. Nestor says he uses 0.3 cc, 31-gauge insulin syringes because they are inexpensive, costing only about 20 cents apiece, and very sharp, which makes the injection very comfortable for the patient.

“The botulinum toxin can be drawn up into these syringes after the vial is reconstituted and left ready to use in the refrigerator. This approach makes botulinum toxin treatments very efficient, easy and safe,” Dr. Nestor says.

Infection prophylaxis
Dr. Nestor also reviewed recommendations for infection prophylaxis to point out that many dermatologists are prescribing antibiotics unnecessarily to prevent infective endocarditis or prosthetic device infections.

“Endocarditis prophylaxis is indicated only when operating on infected skin in high-risk patients, defined as those with a prosthetic heart valve, previous endocarditis, complex cyanotic congenital heart disease, or a surgically constructed systemic pulmonary shunt, and it is not recommended for incision or biopsy of clean, noninfected skin,” Dr. Nestor says.

For patients with prosthetic joints, only those with a contaminated wound or infected skin whose prosthesis was implanted within the past six months are definite candidates for prophylaxis, while prophylaxis may be considered for those having clean-contaminated surgery or involving mucosa with recent prosthetic device surgery (less than six months).

“Patients with prosthetic devices are being seen more and more, and the guidelines for infection prophylaxis for these individuals are a little less clear than for endocarditis prophylaxis. However, there is no need to prescribe antibiotics if the skin is clean and intact,” Dr. Nestor says.

Minding MRSA
Brian Berman, M.D., Ph.D., voluntary professor of dermatology and cutaneous surgery, University of Miami Miller School of Medicine, offered tips based on some recent literature. He says that in a patient who presents with a recurrent methicillin-resistant Staphylococcus aureus (MRSA) infection, clinicians might consider household contamination as the source.

A study investigating commonly touched surfaces in 35 homes isolated MRSA from sink faucets, door handles, bathtubs, dish towels and pet food dishes, suggesting targets for cleaning (Scott E, Duty S, McCue K. Am J Infect Control. 2009;37(6):447-453). Presence of a household cat was also highly associated with MRSA isolation, Dr. Berman says.

Treating warts
Results of a small, prospective, randomized, double-blind study suggest that oral zinc sulfate might be considered a simple and safe treatment for warts. The investigation Dr. Berman referred to assigned patients with multiple, recalcitrant warts to receive cimetidine 35 mg/kg/day (maximum 1,200 mg/day) or zinc sulfate 10 mg/kg/day (maximum 600 mg/day) for three months (Stefani M, Bottino G, Fontenelle E, et al. An Bras Dermatol. 2009;84(1):23-29). There were nine patients in each treatment group, all but one patient who was in the zinc sulfate group completed the study, and complete clearance was achieved by five of the eight zinc sulfate patients but none of the cimetidine-treated patients, he says.

A subsequently published open-label study enrolling 26 patients treated with zinc sulfate 10 mg/kg/day (maximum 600 mg/day) lends further support (Mun JH, Kim, SH, Jung DS. J Dermatol. 2011;38(6):541-545), Dr. Berman says.

Among 26 patients who finished the two-month course of treatment, 50 percent had a complete response and remained wart-free at six months. Complete response rates for common, flat and plantar warts were 57, 40 and 33 percent, respectively.

Nail disease
Phoebe Rich, M.D., adjunct professor of dermatology, Oregon Health & Science University, Portland, offered diagnostic and surgical tips for nail disease. She says that while surgery on an infected nail should be avoided whenever possible, if surgery is necessary, adding the antibiotic clindamycin to the local anesthesia used to anesthetize the digit is useful.

“Simply adding 0.15 cc of injectable clindamycin 150 mg/mL to a full unused 50 cc bottle of lidocaine offers a low-cost approach for local rather than systemic antibiotic prophylaxis during nail surgery,” she says.

“The technique was described as a method for antibiotic prophylaxis in general dermatologic surgery wounds in an article published in 2002 (Huether MJ, Griego RD, Brodland DG, et al. Arch Dermatol. 2002;138(9):1145-1148),” she adds. “However, I find it very useful for nail surgery and keep a vial on hand in the refrigerator by mixing it up fresh every month.

For most nail surgery, a wing block around the nail provides rapid, effective anesthesia allowing painless surgery, she says.

Considering the tendency of delicate nail specimens to curl up when placed in a specimen bottle, which can confuse orientation, Dr. Rich recommends placing the specimen immediately onto a template created by drawing the nail unit on a piece of filter paper.

“This is also a nice tool to facilitate communication with the pathologist about the preferred method of sectioning, because the specimen will stay attached to the filter paper through processing and slide preparation,” Dr. Rich says.

She also reminds colleagues to include common, benign and malignant etiologies in their differential diagnosis for red lines (longitudinal erythronychia) in the nails. There are multiple possible causes for the red bands, she says, including glomus tumors, onychopapilloma and squamous cell carcinoma, but it may simply be the result of a patient buffing or filing ridges on the surface of the nail plate, causing thinning that allows the underlying vessels to show through.

Disclosures: Drs. Rich, Berman and Siegel report no relevant financial interests. Dr. Nestor is on the advisory board and is a speaker for Allergan and Merz and receives research grants from Merz.