Patch Testing for Metal Allergy With Manufacturer-Supplied Materials Before Nuss Bar Insertion.

INTRODUCTION: The increasing use of metal implantable devices has raised awareness of nickel allergy. Preoperative patch testing for patients with pectus excavatum (PE) with a known metal allergy or history of atopy is an accepted practice before the Nuss procedure. The Nuss bar manufacturer offers a metal disc for preoperative testing for metal sensitivities. However, the efficacy of this disc is not well understood. OBJECTIVE: The purpose of this study was to determine the sensitivity of the metal disc in detecting nickel allergy compared with that of standard patch testing. METHODS: Two PE patients were referred for preoperative patch testing with the metal disc to screen for metal allergy before the Nuss procedure. Based on our initial findings, 7 patients without PE scheduled for patch testing for the evaluation of chronic dermatitis were additionally tested with the metal disc if they were found to have risk factors for nickel allergy. All patch testing was performed according to set standards. CONCLUSIONS: The metal disc may not be adequately sensitive to determine nickel allergy before the Nuss procedure. Patch testing alone with standard formulations of nickel sulfate in petrolatum may be more sensitive in diagnosing nickel allergy.

Psoriasis: can statins play a dual role?

Recently, a strong association between "psoriasis" and "atherosclerosis" has emerged. Psoriasis patients have an increased prevalence of atherosclerotic disease including coronary artery, cerebrovascular, and peripheral vascular diseases. The exact connection between psoriasis and atherosclerosis remains unclear, but it is thought that inflammation, which plays an important role in both diseases, may be the causative link. Nevertheless, psoriasis patients suffer from an increased burden of atherosclerotic disease and most commonly die from "coronary artery disease" (CAD). Psoriatic patients have an increased prevalence of CAD risk factors and an increased risk of myocardial infarction (MI). One CAD risk factor in psoriasis patients that can easily be managed is "hyperlipidemia." "Statins" are safe, cost-effective, and have been proven to be highly effective in preventing CAD, including MI, in patients with hyperlipidemia. Furthermore, in addition to their lipid lowering properties, statins have anti-inflammatory immunomodulator activities that may be beneficial in several autoimmune diseases including psoriasis. Considering the safety and cost-effectiveness of statins, we feel that it is worth investigating if statins can play a dual role in psoriasis by treating the increased atherosclerotic disease burden in these patients through their lipid lowering effects and by decreasing psoriatic disease activity through their anti-inflammatory immunomodulatory properties.

Contact dermatitis from a prosthesis.

Patients wearing a prosthesis face a wide variety of medical problems. Skin complications have long been recognized, but their prevalence is still unknown. The most frequently reported disorders are allergic contact dermatitis (ACD), acroangiodermatitis, epidermoid cysts, epidermal hyperplasia, follicular hyperkeratosis, verrucous hyperplasia, bullous diseases, hyperhidrosis, infections, malignancies, and ulcerations. Contact dermatitis represents one-third of the dermatoses in amputees wearing prostheses. All patients who are suspected of having ACD should be patch tested with standard allergen series as well as materials from the patient's own prosthesis, topical medicaments, moisturizers, and cosmetics. We report a patient with an ACD to mixed dialkyl thiourea present in the rubber parts of his below-the-knee prosthesis. Thiourea derivates are used as accelerators in the manufacture of chloroprene rubber and as fixatives in photography and photocopy paper. Allergy to thiourea is relatively uncommon; different studies have shown a prevalence of 0.7% up to 2.4% in patch-tested patients. Thiourea derivates are often the allergic sources in ACD involving high-grade rubber products made of neoprene such as diving suits, protective goggles, knee braces, and continuous positive airway pressure masks. They are also present in the rubber material of prostheses, as in the case of our patient.