Several visible and infrared lasers and light sources have produced positive changes in the clinical and histologic appearance of photoaged skin. Photodynamic therapy (PDT) using a photosensitizing compound may enhance the effects of some of these light-based therapies. Photodynamic therapy using 5-aminolevulinic acid has been examined as a therapy for acne, superficial skin cancers, and photoaging, but data quantifying the molecular events in the epidermis and dermal matrix with respect to photodamage are lacking. In this case series, Orringer et al demonstrated statistically significant increased presence of procollagen types I and III in response to PDT. The degree of pretreatment p53 immunostaining was also found to correlate with the peak production of type I procollagen, suggesting that more profoundly sun-damaged skin may be more responsive to PDT.
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Cutaneous amebiasis (CA) is characterized by painful ulcers laden with trophozoites of Entamoeba histolytica that damage the skin and underlying soft tissues. Involvement may be limited to the skin or may include other organ systems such as the gastrointestinal tract, liver, lungs, and central nervous system. In this retrospective case series, Magaña et al describe 26 patients with cutaneous amebiasis, reporting patient demographics, associated illnesses, and diagnostic methods. Direct and indirect mechanisms for skin inoculation are described, and the authors suggest that CA be considered in the differential diagnosis of any ulcer in the diaper area of a child. Malnutrition, poor hygiene, and preexisting disease contribute to the development of CA in infants and small children, highlighting the public health importance of this condition.
See page 1369
Multicentric reticulohistiocytosis (MR) is a rare granulomatous disease characterized by cutaneous nodules; symmetric, destructive polyarthritis; and associated malignant neoplasm. Although the pathophysiologic characteristics of MR remain unclear, an immunologic basis is likely. Growing evidence points to proinflammatory cytokine involvement, including tumor necrosis factor, the inhibition of which might be expected to emerge as a promising therapeutic option. In this case report, Kalajian and Callen describe a 63-year-old patient with recalcitrant MR who experienced a rapid and sustained improvement in his cutaneous, articular, and constitutional manifestations during 12 months of tumor necrosis factor inhibition treatment with infliximab.
See page 1360
Dermatomyositis (DM) is an inflammatory autoimmune myopathy characterized by proximal muscle weakness, muscle inflammation, and typical cutaneous signs. While the pathogenesis of DM remains unclear, recent gene microarray studies reveal a signature disease association with type I interferon α– or interferon β–related genes. In this case report, Somani et al describe a patient with multiple sclerosis who developed severe DM induced by interferon beta therapy. In vitro studies have revealed interferon pathway activation, consistent with the central role for type I interferons, in the pathogenesis of DM and implicating interferon beta therapy in the development of DM in this patient. Clinicians should be alert to possible induction of DM in their patients receiving interferon-based therapies or other immunomodulators known to induce type I interferon signaling.
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Nodular melanoma (NM) may arise in normal skin or in a precursor lesion but without the presence of a radial growth phase. Even in its early stages, NM has the potential to metastasize. Clinical diagnosis may be difficult because the classic clinical criteria for the diagnosis of melanoma are lacking. Dermoscopic diagnosis is confounded in some cases because the asymmetry may be less marked than in the more common superficial spreading melanoma (SSM). Reflectance-mode confocal microscopy is a new technique for the in vivo study of cutaneous tumors. In this case series, Segura et al correlate the histopathologic findings in NM and SSM with dermoscopy and confocal microscopy, confirming the promise this technique holds for the study of melanocytic lesions in general, and NM specifically.
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This Month in Archives of Dermatology. Arch Dermatol. 2008;144(10):1271. doi:10.1001/archderm.144.10.1271