Daylight photodynamic therapy with methyl aminolevulinate cream as a convenient, similarly effective, nearly painless alternative to conventional photodynamic therapy in actinic keratosis treatment: a randomized controlled trial.

BACKGROUND: Daylight photodynamic therapy (DL-PDT) of actinic keratosis (AK) has shown preliminary efficacy and safety results comparable to conventional photodynamic therapy (c-PDT), using methyl aminolevulinate (MAL) cream. OBJECTIVES: To demonstrate the efficacy and safety of DL-PDT vs. c-PDT in treating mild facial/scalp AK. MATERIALS AND METHODS: This 24-week randomized, controlled, investigator-blinded, multicentre, intra-individual efficacy (non-inferiority) and safety (superiority regarding pain) study enrolled 100 subjects. AKs on the face/scalp were treated once, with DL-PDT on one side and c-PDT on the contralateral side. Primary end points for DL-PDT at week 12 were efficacy [non-inferiority regarding complete lesion response (mild AK)] and safety (superiority regarding subject's assessment of pain). Lesions with complete response 12 weeks after one treatment session were followed until week 24. The safety evaluation included incidence of adverse events. Subject satisfaction was classified using a questionnaire. RESULTS: At week 12, the complete lesion response rate with DL-PDT was non-inferior to c-PDT (89·2% vs. 92·8%, respectively; 95% confidence interval -6·8 to -0·3), confirmed by intention-to-treat analysis. Additionally, regardless of the treatment used, 96% of mild lesions were maintained in complete response 24 weeks after the PDT session. For DL-PDT, subject-reported pain was significantly lower (0·8 vs. 5·7, respectively; P < 0·001), with better tolerability and significantly higher subject satisfaction regarding convenience and outcome. CONCLUSIONS: Daylight-mediated PDT was not inferior in efficacy to Metvix c-PDT (mild AK response rate), better tolerated, nearly painless and more convenient for patients.

Mid-dermal elastophagocytosis presenting as a persistent reticulate erythema.

Two men are presented with a widespread persistent reticulate erythema concentrated within the chronically sun-damaged skin on their trunk. A fine papular element was present in one case and both lacked annular lesions. One patient was human immunodeficiency virus positive. Multiple skin biopsies showed an interstitial infiltrate of histiocytes containing multiple elastic fibres in the upper dermis. There was scant perivascular lymphocytic inflammation but no evident necrobiosis or palisaded granulomas seen typically with granuloma annulare. Elastic stains showed focal mid-dermal elastolysis. Diffuse reticulate erythema in sun-damaged skin may be a clinical marker for elastophagocytosis. This presentation differs from that previously described with actinic granuloma, diffuse granuloma annulare or the inflammatory phase of mid-dermal elastolysis and expands the clinical spectrum of this phenomenon.

Allergic contact dermatitis in dentistry.

Allergic contact dermatitis (ACD) in dentistry may affect dentists and orthodontists, technicians, nurses and patients. Changes to dental practice in recent years have altered the reported frequencies of allergens causing ACD in both dental personnel and patients. Allergic contact dermatitis to medicaments, metals and glutaraldehyde were previously common allergens in dentistry; however, widespread adoption of rubber gloves by staff has resulted in a significant increase in ACD to glove allergens in both dental staff and their patients, while affording protection against the traditional allergens. Both public concerns about potential toxicity of metals in oral restorations and a greater demand for cosmetic dentistry, have resulted in greater use of acrylics and resins by dental personnel, exposing them to highly allergenic materials. Dermatologists need to be aware of the newer allergenic materials used in dentistry in order to correctly manage skin diseases in this high-risk group.

Tea tree oil allergy: what is the offending agent? Report of three cases of tea tree oil allergy and review of the literature.

Tea tree oil is currently enjoying popularity as a 'cure-all' for a variety of skin conditions, from infections to psoriasis, and many household and personal products containing Melaleuca oil are available. However, despite its chemical complexities and enthusiastic use, there have been only a few reports of allergic reactions to tea tree oil. At the Skin and Cancer Foundation (Sydney, NSW, Australia), three of 28 normal volunteers tested strongly positive to patch testing with tea tree oil. Following further patch testing with tea tree oil constituents, all three patients reacted strongly to two preparations containing sesquiterpenoid fractions of the oil. Because patients often neglect to mention that they have used 'natural' remedies, it is important that physicians are aware of the potential adverse effects of these products. Furthermore, identification of the allergenic ingredients in tea tree oil may assist the growing industry to produce safer products.

Allergic contact dermatitis to ethoxyquin in a farmer handling chicken feeds.

Farm workers handling animal feeds are exposed to a variety of chemicals, some of which may cause allergic contact dermatitis. A case of allergy to ethoxyquin (a preservative added to chicken feed to inhibit vitamin degradation) in a chicken farmer is presented. Although the offending allergen was identified in this patient, it proved difficult to find ethoxyquin-free chicken feed products and the patient's dermatitis persisted. When facing the clinical problem of dermatitis in animal workers, the possibility of allergic contact dermatitis to components in animal feeds must be considered.

Bioactive tumour necrosis factor alpha but not granulocyte-macrophage colony-stimulating factor correlates inversely with Langerhans's cell numbers in skin tumours.

Langerhans' cells (LCs) are thought to play an important role in presentation of tumour antigens for the induction of anti-tumour immunity. Epidermis overlying some transplanted murine skin tumours contains increased numbers of LCs; however, alterations in LC numbers are not related to tumour antigenicity or host immunity, suggesting that another factor(s), such as tumour-produced cytokines, influences LC density. It has been postulated that dendritic epidermal T cells (DETCs) play a role in immunosurveillance within the normal epidermis. Two cytokines which potentially alter LC numbers or function include granulocyte-macrophage colony-stimulating factor (GM-CSF) and tumour necrosis factor-alpha (TNF-alpha). GM-CSF maintains LC viability in culture, and there are reports that it can increase LC density. There is evidence that TNF-alpha induces LC to migrate from the epidermis. In the present study, LC densities in regressor and non-regressor murine skin tumours and overlying epidermis were enumerated, and bioactive GM-CSF and TNF-alpha present in the tumours were measured. We found significantly increased epidermal LC numbers above non-regressor, but not regressor, tumours. DETC numbers were significantly increased above some tumours. Although all tumour types produced TNF-alpha, the regressors, which did not increase LC numbers, produced the most TNF-alpha. In contrast, tumour production of GM-CSF did not correlate with any pattern of alteration of LC density or tumour growth. Tumour production of neither cytokine nor tumour growth correlated with DETC numbers overlying tumours. Our results suggest that TNF-alpha may be associated with skin tumour regression and may prevent LC accumulation by tumours.

Generalised granuloma annulare successfully treated with pentoxifylline.

Generalised granuloma annulare (GA) is a chronic disease of unknown aetiology and is recalcitrant to many treatment regimes. Some investigators have suggested that an immune medicated vasculitis may be involved in the pathogenesis of GA. We describe a patient with a ten year history of generalised GA, who showed dramatic clearing of the majority of papules after four weeks of treatment with pentoxifylline. This drug has shown promising results in the treatment of many dermatologic disorders including necrobiosis lipoidica diabeticorum, leukocytoclastic vasculitis and Raynaud's phenomenon. Pentoxifylline is thought to reduce blood viscosity via effects on all major blood components, and its clinical effectiveness in generalised GA lends support to a model of immune-medicated vasculitis in the pathogenesis of this disorder. Thus, pentoxifylline offers a well-tolerated and effective alternative to the treatment options available for patients with granuloma annulare.

Dermal myiasis in an Australian traveller.

Myiasis, the infestation of body tissues by the larvae of flies, occurs infrequently in Australian tourists who return from areas where certain species are endemic. Some of these insect species such as Cochliomyia hominivorax and Chrysoma bezziana (New and Old World screw-worms respectively) are responsible for significant disease in livestock as well as in humans. We report a patient who travelled extensively through South America and returned to Australia with a subcutaneous nodule containing a large larva of the species Dermatobia hominis. Because of the risk of travellers introducing unwanted species of flies into our country, it is important for doctors to suspect the possibility of furuncular myiasis, and to obtain accurate identification of the larva.