Systemic contact dermatitis and allergy to biomedical devices.

Systemic contact dermatitis (SCD) refers to a skin condition where an individual who is cutaneously sensitized to an allergen will subsequently react to that same allergen or a cross-reacting allergen via the systemic route. It occurs to allergens including metals, medications, and foods. There has been recent interest in metal allergy as it relates to the implantation of devices such as orthopedic, dental, cardiac, and gynecologic implants. This review will briefly address all causes of systemic contact dermatitis with a special and expanded focus on metal implant allergy. We present literature on SCD to various metal biomedical devices, patch testing for diagnosis of metal allergy pre and post implantation and treatment.

Mobile Phones: Potential Sources of Nickel and Cobalt Exposure for Metal Allergic Patients.

The use of cellular phones has risen exponentially with over 300 million subscribers. Nickel has been detected in cell phones and reports of contact dermatitis attributable to metals are present in the literature. We determined nickel and cobalt content in popular cell phones in the United States. Adults (>18 years) who owned a flip phone, Blackberry®, or iPhone® were eligible. Seventy-two cell phones were tested using SmartPractice's® commercially available nickel and cobalt spot tests. Test areas included buttons, keypad, speakers, camera, and metal panels. Of the 72 cell phones tested, no iPhones or Droids® tested positive for nickel or cobalt. About 29.4% of Blackberrys [95% confidence interval (CI), 13%-53%] tested positive for nickel; none were positive for cobalt. About 90.5% of flip phones (95% CI, 70%-99%) tested positive for nickel and 52.4% of flip phones (95% CI, 32%-72%) tested positive for cobalt. Our study indicates that nickel and cobalt are present in popular cell phones. Patients with known nickel or cobalt allergy may consider their cellular phones as a potential source of exposure. Further studies are needed to examine whether there is a direct association with metal content in cell phones and the manifestation of metal allergy.

Current strategies in treating severe contact dermatitis in pediatric patients.

Allergic contact dermatitis in children is underdiagnosed and undertreated, and its incidence is increasing. Appropriate history taking and the suspicion for allergic contact dermatitis is essential, and patch testing remains the gold standard in diagnosis. Avoidance of the offending allergen, once identified, is the first goal of treatment. Medical therapies include topical corticosteroid and topical immunomodulators. In severe cases, oral corticosteroids or immunomodulators are utilized, although prospective randomized trials for the treatment of this disease in children are lacking. A PubMed literature search was performed to identify publications on allergic contact dermatitis in the pediatric population with the keywords: dermatitis, children, allergic contact dermatitis, pediatrics, contact hypersensitivity, contact allergy, treatment, and management. This review will address the major principles behind the diagnosis and management of this disease in the pediatric population, and highlight useful strategies that may result in improved treatment of this condition.

Allergic rhinitis.

Allergic rhinitis is a costly disease associated with significant morbidity. It impacts the quality of life of millions of individuals, particularly in industrialized nations, and it is on the rise. Lost productivity and total healthcare expenditure exceeds several billion dollars annually in the United States, with an estimate of >$6 billion spent on prescription medications alone. It is also associated with asthma and other atopic conditions, sinusitis, otitis media, and sleep apnea. Primary care physicians should be well adept at recognizing and initiating empiric first-line therapy for chronic rhinitis. Allergen avoidance, topical nasal steroids, and antihistamines may be sufficient for some patients. In most cases, referral to a board-certified allergy specialist for skin testing and targeted management is indicated. It is essential to make sure that patients abstain from using antihistamines at least 1 week prior to reporting to the allergist for skin testing in order to avoid false-negative results. Traditional subcutaneous allergen immunotherapy, when performed by an experienced allergist, affords relief in >75% of cases. The growing armament of treatment options for refractory allergic rhinitis includes oral and sublingual immunotherapy, recombinant allergens, conjugated DNA vaccines, and anti-immunoglobulin E monoclonal antibody.

Metastatic melanoma causing jejunal intussusception.

The gastrointestinal (GI) tract is a common site of melanoma metastases although reports of small bowel intussusception are relatively rare. Most patients with intussusception will be symptomatic and resection will provide significant palliation. In rare instances, patients will have solitary metastases to the small intestine, and resection can provide long-term palliation and chance for cure. We describe a case of a patient with a widely metastatic melanoma who presented with crampy abdominal pain and CT findings of small bowel metastases. Exploration revealed jejunojejunal intussusception and resection provided excellent palliation.

A second large plasmid encodes conjugative transfer and antimicrobial resistance in O119:H2 and some typical O111 enteropathogenic Escherichia coli strains.

A novel and functional conjugative transfer system identified in O119:H2 enteropathogenic Escherichia coli (EPEC) strain MB80 by subtractive hybridization is encoded on a large multidrug resistance plasmid, distinct from the well-described EPEC adherence factor (EAF) plasmid. Variants of the MB80 conjugative resistance plasmid were identified in other EPEC strains, including the prototypical O111:NM strain B171, from which the EAF plasmid has been sequenced. This separate large plasmid and the selective advantage that it confers in the antibiotic era have been overlooked because it comigrates with the virulence plasmid on conventional gels.