Systemic allergic contact dermatitis associated with allergy to intraoral metals.

Contact (allergic) dermatitis is a skin disorder related to natural exposure to various allergens. Systemic contact dermatitis (SCD) describes a cutaneous eruption in response to systemic exposure to an allergen. The exact pathologic mechanism remains uncertain. Herein we describe a 36-year-old woman with symmetric systemic allergic contact dermatitis, unresponsive to conventional treatment, associated with dental alloy-contact hypersensitivity. We did skin patch testing and the blood lymphocyte transformation test (LTT) from the dental allergen series to assess contact allergy to restorative dental materials. On patch testing, positive allergic contact dermatitis reactions to metals occurred (nickel, potassium dichromate, and gold). Nickel hypersensitivity was confirmed by LTT, which also revealed silver-amalgam sensitization. Our case report highlights the need to consider adverse reactions to base-metal dental alloys in the differential diagnosis of cases of systemic allergic contact dermatitis.

Photodynamic therapy to treat periimplantitis.

AIM: : Periimplantitis is a bacterial complication after dental implants implantation. Photodynamic therapy (PDT) implies the use of low-power laser in combination with appropriate photosensitizer to increase the detoxification of the implant surfaces. Little information exists about PDT in the treatment of periimplantitis. A randomized comparative case-control study has been conducted with 20 patients and 20 controls to compare the efficacy of antimicrobial PDT versus surgical therapy in patients with periimplantitis, who have received dental implants with rough surfaces. MATERIALS AND METHODS: In the surgery group, mucoperiosteal flap surgery was used with scaling on implant surfaces and debridement of granulation tissue. Microbiologic testing was evaluated before and after intervention treatment, at 12 and 24 weeks in the study subjects. DISCUSSION: Total anaerobic counts of bacteria did not differ significantly between patients assigned to receive PDT and those assigned to receive surgical therapy (mean, 95.2% and 80.85%, respectively). PDT was associated with a significant decrease in bleeding scores (P = 0.02) as well as inflammatory exudation (P = 0.001). CONCLUSION: Treatment with PDT in patients with periimplantitis was not associated with major reduction of total anaerobic bacteria on the rough surfaces of dental implants as compared with surgical therapy. A significantly lower proinflammatory index of periimplantitis was observed in the PDT group at 24 weeks of follow-up.

Metal sensitivity in patients with orthopaedic implants: a prospective study.

BACKGROUND: Sensitization to orthopaedic implant materials is an unpredictable event that might affect implant performance. OBJECTIVES: In candidates for hip or knee joint prosthesis implantation, to evaluate preoperative assessments for identifying patients with metal sensitivity, to determine the percentage of patients who developed metal sensitivity at 1 year after prosthesis implantation, and to examine the clinical relevance of patch tests and lymphocyte transformation tests (LTT-MELISA®) for the evaluation of metal sensitization. PATIENTS AND METHODS: A total of 100 patients referred for total hip or total knee arthroplasty were assessed preoperatively and then at 1 year post-implantation by means of patch tests with the metals present in the implant alloys. In a pilot study, 20 patients also underwent both patch testing and a lymphocyte transformation test (LTT-MELISA®) for the same metals. RESULTS: Only 72 of 100 patients were patch tested both before and after surgery, and 12 of 20 also underwent LTT-MELISA® before and after surgery. Of 31/100 patients with an apparent history of nickel sensitivity determined during preoperative assessment of subjects, 12 tested negative on both tests, and 4 with a negative history of nickel sensitivity tested positive. One year post-implantation (72 patients), 5 patients who had initially tested negative for a metal allergy became positive for at least one or more metal constituents of the prosthesis on at least one or the other test. CONCLUSIONS: Given the discrepancies between the information obtained while taking patient histories and test results, preoperative history-taking alone appears to be insufficient for identifying patients with metal sensitivity. Moreover, the increase in the percentage of patients who tested positive for metal sensitivity 1 year post-implantation suggests the possibility of prosthesis-induced sensitization. Therefore, objective determination of metal sensitivity at preoperative assessment should be considered in planning arthroplasty intervention, as it would help the surgeon in selecting the most appropriate prosthesis for the patient and could benefit implant performance.

Toxic effects of mercury in humans and mammals.

The clinical manifestations of methylmercury toxicity do not differ greatly according to the acute and/or chronic methylmercury overexposure.

Italian Expert Consensus on Clinical and Therapeutic Management of Multiple Chemical Sensitivity (MCS).

Multiple chemical sensitivity (MCS) is a multisystem, recurrent, environmental disorder that flares in response to different exposures (i.e., pesticides, solvents, toxic metals and molds) under the threshold limit value (TLV) calculated for age and gender in the general population. MCS is a syndrome characterized by cutaneous, allergic, gastrointestinal, rheumatological, endocrinological, cardiological and neurological signs and symptoms. We performed a systematic review of the literature to summarize the current clinical and therapeutic evidence and then oriented an eDelphi consensus. Four main research domains were identified (diagnosis, treatment, hospitalization and emergency) and discussed by 10 experts and an MCS patient. Thus, the first Italian MCS consensus had the double aim: (a) to improve MCS knowledge among healthcare workers and patients by standardizing the clinical and therapeutic management to MCS patients; and (b) to improve and shed light on MCS misconceptions not supported by evidence-based medicine (EBM).

Alopecia Areata and Toxic Metals.

Toxic metals are not so rare but are often neglected causes of alopecia areata in men and women. Thallium, arsenic, selenium, and mercury are the most common cause of metals-related alopecia, which is what Vicky Yu and colleagues' found. Other than the presence of thallium, arsenic, mercury, and selenium, cadmium, bismuth, lithium, and copper should also be taken into account when dermatologists are considering toxic metals as a potential cause of alopecia areata in humans.

Prevalence and risk factors for multiple chemical sensitivity in Australia.

The author found that the prevalence of diagnosed multiple chemical sensitivity (MCS) in Australia was 6.5%. No mention is made about the role of exposure to metals. Exposure to metallic elements has been associated with MCS. Metals are a well-known primary risk factor for idiopathic environmental intolerance. It is important that the medical approach designed to reduce the risk factors for MCS includes preventive strategies of metal exposure.

Molecular mechanisms triggered by mercury.

Mercury is an ubiquitous environmental toxin that causes a wide range of adverse health effects in humans. Three forms of mercury exist: elemental, inorganic and organic. Each of them has its own profile of toxicity. Exposure to mercury typically occurs by inhalation or ingestion. Mercury can be an indoor air pollutant, however industry emission remains the most important source of inhaled mercury. Furthermore, fresh water and ocean fish may contain large amounts of mercury and dental amalgam can be another important source of inorganic and mercury vapor. The present review discusses the current information on mercury toxicity and the distinct toxicologic profile of the three forms of mercury. The existing therapeutics, new therapeutics development or agents for treating mercury poisoning will also discussed. Since in general low levels of mercurial are tolerable, herein, we also discuss the defensive mechanisms developed by the cell to protect itself against mercury injury. This aspect may be useful to provide a biological protection against toxic effects exerted by mercury or by specific forms of mercury in view of a medicinal purposes.

Dental amalgam, mercury toxicity, and renal autoimmunity.

Chronic exposure to elemental metallic mercury may induce an immunological glomerular disease. Since humans are exposed to mercury vapor (Hg0) from dental amalgam restorations and kidney is an important target organ of mercury vapor and mercury deposition in kidney increases proportionally with the dose, our aim was to test the occurrence of specific antibodies to antiglomerular basement membrane (anti-GBM-IgG) among individuals with adverse effects to mercury from dental amalgam fillings. We selected a group of patients (n=24) with a history of long-term exposure to mercury vapor from mercury-containing amalgam fillings and showing adverse effects that were laboratory confirmed. Enzyme-linked immunosorbent assays (ELISAs) were used to evaluate serum levels of antibodies to anti-GBM-IgG. None of the patients showed evidence of anti-GBM autoimmunity, either in subgroups with strong allergy to mercury or its compounds (i.e., organic mercury) or in those patients who had past thimerosal-containing vaccines coverage (7 of 24). There was no evidence of the presence of circulating anti-GBM antibodies in subjects suffering from adverse events due to long-term exposure to mercury from dental amalgams, even in individuals who presented allergy to mercury.

Photopatch tests: an Italian multicentre study from 2004 to 2006.

BACKGROUND: Evaluation of possible photoallergic contact dermatitis in at-risk populations is often not undertaken, and an agreed methodology for investigation is uncommonly used. OBJECTIVES: We conducted a retrospective multicentre study to determine the prevalence of photoallergic contact dermatitis in Italy. METHODS: A total of 1082 patients with histories and clinical features suggestive of photoallergic contact dermatitis were evaluated. All the patients had undergone photopatch testing with allergens proposed for Italy as well as other substances suggested by each patient's personal history. RESULTS: 234 patients (21.6%) were positive to at least one test substance of the standard photopatch testing series or to added substances. 234 patients (21.6%) were positive to at least one substance with a total of 290 reactions. 204 of the reactions were typically photoallergic; 68 reactions were allergic and within this group 10 were photoaugmented reactions; 18 reactions were considered to be phototoxic. CONCLUSION: The predominant group of photoallergens was drugs, followed by organic UV filters and antimicrobial agents.

Large oral ulcer of tongue related to dental trauma.

A 36-year-old Philippine male has a several month-history of burning pain of his tongue with lingual erythema and oral bleeding. Here we describe a classical case of oral chronic ulcer related to mechanical dental trauma. In this case, unilateral crossbite malocclusion was able to produce oral mucosal lesion that was sufficient to cause a large, chronic tongue ulcer and subsequent mild epithelial dysplasia. A specific tongue-retaining device was made. In absence of dental trauma, his chronic ulcer of the tongue resolved within a few weeks. This case suggests evidence on the direct relationship between chronic oral trauma and the potential occurrence of a dysplastic process.