The 70th annual meeting of the American Academy of Dermatology, held from March 16 to 20, 2012, in San Diego, California., drew a record attendance of more than 19,300 clinicians and investigators from around the world. The gathering included approximately 850 experts who presented scientific sessions on recent research in the medical, surgical, and cosmetic treatment of the skin, hair, and nails. Some key presentations are summarized in this article.
. 2012 Jun;37(6):364–366.
P T. 2012 Jun;37(6):364.
Patients with psoriasis often have comorbid conditions, such as arthritis, obesity, metabolic syndrome, vascular disease, fatty liver, and psychiatric problems. For this reason, a new multidisciplinary psoriasis clinic at University Hospitals includes a rheumatologist, a nutritionist, and a psychiatrist along with its staff of dermatologists.
Dr. Korman remarked that if various specialists can be gathered in one location to discuss psoriasis cases together, “you can potentially manage these patients more effectively. You might be able to decrease prescription costs and the risk of drug interactions. You could potentially conserve resources because patients may need fewer visits and less monitoring.”
Along with medical needs, he added, psoriasis brings “an enormous psychosocial need. Many of these patients are so stigmatized by their disease that to even suggest that they might need to see a psychiatrist will get them upset, and they won’t want to do it.”
Therefore, instead of referring patients for a separate psychiatric appointment, the clinic’s psychiatrist is available to join the dermatologist and the patient in the examination room. This makes nearly all patients willing to meet with the psychiatrist, Dr. Korman said.
The clinic tracked the diagnoses that its psychiatrist made for the first 70 psoriasis patients and found that depression and alcohol abuse were the major psychiatric comorbidities. Together, they accounted for nearly 75% of the psychiatric diagnoses.
“We had one patient admitted directly from the clinic because the patient was talking about suicide,” Dr. Korman said. “Another patient was admitted directly to chemical dependency treatment.”
In 2010, University Hospitals gathered representatives, including rheumatologists, dermatologists, a cardiologist, and a psychiatrist, from nine academic departments in the U.S. and Canada to discuss the feasibility of multidisciplinary psoriasis care. “The biggest problem with multidisciplinary care is cost,” Dr. Korman remarked.
He added that it’s unclear whether Medicare and other U.S. health care payers would allow more than one specialist to bill for the same patient on the same date. Currently, financial support for multidisciplinary care comes from internal funding, along with contributions from the pharmaceutical industry. In addition, at University Hospitals, a large private gift supports psoriasis research and funds a full-time nurse, who helped get the project started. Numerous North American facilities now provide multidisciplinary psoriasis care.
Dr. Korman said, “It’s our job to document that this adds value and that we can make it cost-effective. Fortunately, the clinic facilitates our research. That’s a big part of these clinics—getting our patients involved in studies we’re trying to do.”
These investigations can involve the evaluation of medications or other interventions or the analysis of the risks of comorbidities.
Ultimately, Dr. Korman said, “Multidisciplinary care would be feasible if it could provide better care and a better quality of life at a lower cost. Even if it’s cost-neutral and provides a better quality of life, it could be feasible.”
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According to Dr. Leyden, oral antibiotics can be effective as monotherapy for even severe acne. However, he added, combining these agents with topical benzoyl peroxide helps to reduce the growing problem of antibiotic resistance.
In the past, he remarked, “Propionibacterium acnes was exquisitely sensitive to multiple classes of drugs, particularly the macrolides, tetracyclines, and sulfonamides, and it was inherently insensitive to aminoglycosides, metronidazole, and mupirocin. Nowadays, almost every patient has mixed populations of both sensitive and insensitive strains.”
The reduction in antibiotic sensitivity pertains mostly to macrolides and related antibiotics, such as clindamycin (Cleocin, Pfizer), he said. However, “there is also a clear decrease in [P. acnes] sensitivity to tetracyclines. Minocycline remains the tetracycline to which the organism is most sensitive.”
In addition, the sensitivity of P. acnes to trimethoprim–sulfamethoxazole (Bactrim) appears to remain unchanged.
“This may reflect less use of that drug in acne,” Dr. Leyden suggested.
In a study of early-onset acne that he co-authored, Dr. Leyden found that the patients were all highly sensitive, especially to erythromycin but less so to clindamycin.1 Although these patients were treatment-naive, he said, “It’s the same pattern we see in adult populations in terms of doxycycline and minocycline. Many studies worldwide have shown that there can be resistance to these drugs.”
In Dr. Leyden’s opinion, interpreting a drug’s minimum inhibitory concentration (MIC) in clinical studies is difficult because the methods used for this purpose are highly aqueous.
“We don’t know what concentration of these drugs get into the follicles,” he remarked.
To estimate drug efficacy, therefore, investigators have had to correlate clinical outcomes with the MIC.
Dr. Leyden has been examining the effects of antimicrobial agents in patients with varying MICs. In an unpublished study, patients with an MIC of 512 mcg/mL or greater and who used topical clindamycin 1% twice daily showed no appreciable reduction in P. acnes counts. Conversely, patients “with MICs of less than 256 mcg/mL achieved results very similar to what we found when clindamycin was first introduced in the early 1980s.”
In a subsequent unpublished study, Dr. Leyden combined topical clindamycin with topical tretinoin. Patients with an MIC of 512 mcg/mL or greater achieved P. acnes reductions after 6 weeks, although these reductions were less significant than those in patients with low MICs.
Dr. Leyden also studied the effects of systemic minocycline therapy in 20 patients with P. acnes.
“Patients who had strains with MICs of less than 4 mcg/mL showed a 1.5-log reduction in P. acnes colony-forming units, while those with higher MICs had only a 0.5-log reduction,” he said.
Dr. Leyden remarked, “It’s clear that over a period of 4 to 6 months, patients can go from having a mixture of less sensitive and more sensitive P. acnes, to increasing the number and density of P. acnes that are less sensitive to antibiotics. What can we do about this? Benzoyl peroxide is the answer.”
In a report that he coauthored,2 many of the patients had a very high MIC for multiple drugs. However, by combining topical benzoyl peroxide with oral antibiotics over several weeks, Dr. Leyden and his colleagues were able to reduce the presence of resistant P. acnes strains and to prevent their emergence.
“Therefore,” he said, “with any long-term use of antibiotics—for me, it’s beyond 3 months––patients also should use benzoyl peroxide.”
REFERENCES
- 1.Leyden JJ. Presentation, 69th annual meeting of the American Academy of Dermatology; February 4–8, 2011; New Orleans: [Google Scholar]
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Careful interpretation and thorough biopsy sampling are necessary to distinguish onychomycosis from other diseases microscopically, Dr. Ruben reported.
At the university, she explained: “We’re a little picky about what kinds of samples we like to see histologically.”
She urged physicians to submit both nail plate samples and as much subungual debris as possible. Laboratory staffs typically strain the sample to separate the nail plate from the debris.
Although various methods are available for the histopathological diagnosis of onychomycosis, including cultures, potassium hydroxide stains and, more recently, polymerase chain reaction analysis and Gomori–Grocott methanamine silver stains, Dr. Ruben prefers using periodic acid–Schiff (PAS) staining for this purpose. In a comprehensive review of methods used in diagnosing onychomycosis, PAS staining alone had 94% sensitivity, which matched the most sensitive combination of methods reviewed, namely PAS staining plus two common agar-based culture methods.1
Dr. Ruben pointed out that PAS staining is quicker and simpler than other methods. It also allows the dermatopathologist to consider other organisms that might be present in a nail clipping, she explained, although PAS staining doesn’t allow positive identification of the specific pathogen.
PAS staining can help dermatopathologists identify conditions ranging from psoriasis to pigment disorders, as well as onychomycosis, in nail clippings. She said that diagnosing pigmented onychomycosis, for example, can be tricky clinically and that it is often mistaken for melanocytic neoplasms of the nail. Conversely, just because a dermatopathologist finds onychomycosis in a nail sample, there could still be a melanocytic lesion underneath the nail that doesn’t resolve after the onychomycosis has been treated.
Candidiasis often presents as a paronychial finding or as Candida onycholysis, Dr. Ruben said. The latter form is predominant on histological sections.
Yeasts such as Candida contain no hyphae. However, she said, “When we see perforating hyphae or very bulbous, distorted hyphae, perhaps with truncated spores, we should raise the possibility that there may be molds.”
Dermatopathologists also might see Pseudomonas on nail plates, Dr. Ruben said. These organisms create diffusible pigment that fluoresces in vivo but not in nail clippings. On microscopic examination, she explained:
“We don’t see bacteria; we see a lemon-yellow discoloration of the nail (specifically corneocytes), which is very characteristic of Pseudomonas.”
Finally, dermatophytoma is a severe form of onychomycosis that resists treatment. It is deeply situated within the nail unit, forming a loculated ball, or biofilm, of fungus and other organisms. A biofilms occurs when organisms create an environment that promotes their own growth.
Dr. Ruben added, “It can occur in the nail, under the nail, or throughout the nail.”
When viewed microscopically, the fungi may be thick-walled, she said.
“You may see spores, even though you’re dealing with dermatophytic hyphae. There may be bacteria as well. You need a culture to decide exactly what they are.”
Dr. Ruben said, “These lesions often benefit from nail avulsion. You must do some sort of debridement or chemical destruction to get rid of the loculated fungal ball.”
REFERENCE
- 1.Lawry MA, Haneke E, Strobeck K, et al. Methods for diagnosing onychomycosis: A comparative study and review of the literature. Arch Dermatol. 2000;136:1112–1116. doi: 10.1001/archderm.136.9.1112. [DOI] [PubMed] [Google Scholar]
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Many patients with basal cell carcinoma (BCC) or squamous cell carcinoma (SCC) require surgical treatment, often with Mohs micrographic surgery for tumors of the head and neck. However, Mohs surgical excision might not be appropriate in all cases. Because of extensive background actinic damage, “you can’t tell where one skin cancer ends and the next one begins,” Dr. Tierney said.
She often uses off-label photodynamic therapy with red light and methyl aminolevulinate (Metvixia, Galderma) to treat patients with extensive actinic damage, non-melanoma skin cancers, or both, on sun-exposed areas (e.g., the extremities, scalp, and face). Two to 3 hours of drug incubation is required.
Dr. Tierney said, “Then we see which precancerous areas or early skin cancers are resolved by photodynamic therapy through its immune system–stimulating properties. Oftentimes, if a patient has many rough, scaly areas that are hypertrophic or regular actinic keratoses, photodynamic therapy will treat the area with one or two applications.”
Thicker lesions are more likely to be invasive SCCs or nodular BCCs. These lesions typically do not respond to field treatment with photodynamic therapy and must be managed surgically.
Dr. Tierney may use photodynamic therapy for specific tumors when surgery might be inappropriate, as in older patients with medical comorbidities, patients who are not optimal surgical candidates, and those with compromised wound healing because of a comorbid condition (e.g., diabetes or vascular disease).
For many superficial skin cancers, she said that patients are often looking for less aggressive approaches. Dermatologists today can offer them many novel approaches, she said.
Even with aggressive curettage and methyl aminolevulinate, which penetrates more deeply than aminolevulinic acid, the reported 5-year cure rates with photodynamic therapy range from 76% to 97% for superficial BCC and from 64% to 92% for nodular BCC, Dr. Tierney said.
For field treatment on the extremities, Dr. Tierney uses the chemo-wrap technique. She applies 5-fluorouracil to the lower leg under an Unna boot wrap, a compression wrap made of gauze soaked in zinc oxide. The wrap is left on for a week at a time, replacing the boot each week for 3 to 16 weeks.
“Patients experience much less irritation when you apply an Unna boot over 5-fluorouracil under occlusion than they would have from simply applying 5-fluorouracil every day without occlusion. The zinc oxide paste in the Unna boot helps to neutralize irritation without compromising effectiveness.”
The compression provided by the Unna boot increases the treatment’s effectiveness, she added. In a series of 30 patients with superficial cancers and precancers, the Unna compression wrap proved very effective. Patients were treated with weekly chemo-wraps for 4 to 12 weeks. Before these wraps were available, study patients underwent an average of 5.5 lower-leg surgeries at Dr. Tierney’s institution. By contrast, during the 3 years since the introduction of chemo-wraps, only two patients have needed surgery.