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Denis Sasseville

Publications and source records attributed to Denis Sasseville.

At least 19 recordsLinked to original sources

Delayed-type hypersensitivity to fragrance materials in a select North American population.

BACKGROUND: In published reports from Europe, 3- and 4-(4-hydroxy-4-methylpentyl)cyclohexene-1-carboxaldehyde (HMPCC) (Lyral) has been described as a common cause of allergic contact dermatitis (ACD). In Europe, the rates of reaction to HMPCC among patients undergoing patch testing for suspected ACD have varied from 1.2 to 17.0%, depending on the country. Data on the incidence of sensitivity to HMPCC among North Americans with suspected ACD have not been reported. OBJECTIVES: The goals of this study were (1) to assess the incidence of delayed-type hypersensitivity reactions to HMPCC among patients undergoing patch testing for evaluation of eczematous dermatitis at six centers throughout North America; (2) to determine the most appropriate concentration of HMPCC to use in performing patch tests; and (3) to compare and contrast the incidence rates for HMPCC hypersensitivity to those for other fragrance materials screened with the North American Contact Dermatitis Group (NACDG) screening tray, which includes fragrance mix, Myroxilon pereirae (balsam of Peru), cinnamic aldehyde, ylang ylang oil, jasmine absolute, and tea tree oil. METHODS: This report represents the prospective multicenter data on patients tested with the fragrance-related allergens on the NACDG standard screening tray and with HMPCC at 5%, 1.5%, and 0.5% concentrations in petrolatum. Statistical analyses were performed with Student's t-test (two tailed) and the chi-square test. RESULTS: Data from 1,603 patients evaluated at five US sites and one Canadian site were analyzed. Most patients (87.8%) were Caucasian. The majority (67%) were women, and 26.2% had a history consistent with atopic dermatitis. The patients ranged in age from 1 to 88 years, and the mean +/- standard deviation was 46.3 +/- 16.5 years. Myroxilon pereirae (balsam of Peru) and fragrance mix were the most frequent patch-test-positive fragrance allergens (6.6% and 5.9%, respectively). Cinnamic aldehyde (1.7%), ylang ylang oil (0.6%), jasmine absolute (0.4%), HMPCC (0.4% for 5% HMPCC, 0.3% for 1.5% HMPCC, and 0.2% for 0.5% HMPCC), and tea tree oil (0.3%) less frequently yielded positive reactions. Men were more likely than women to be allergic to cinnamic aldehyde. Women were more likely than men to be allergic to jasmine absolute. Atopic patients were no more likely to react to fragrance materials than were nonatopic patients. Patients who reacted to jasmine absolute tended to be older than the general population whereas those who reacted to tea tree oil tended to be younger than the general population. There were no other demographic differences between patients who reacted to a given fragrance material and the entire population studied. Testing with fragrance mix and balsam of Peru failed to identify the majority of patients in this study who were found to be sensitized to jasmine absolute, HMPCC, or tea tree oil. CONCLUSION: HMPCC is an uncommon allergen in the North American population. We recommend testing with 5% HMPCC in petrolatum for those patients suspected of having a fragrance allergy.

Adolescent↗

Contact urticaria from carboxymethylcellulose in white chalk.

BACKGROUND: Carboxymethylcellulose (CMC) is widely used in consumer goods, foods, and medicaments as a binder, emulsifier, and viscosity enhancer. Cases of immediate and delayed allergic reactions to this anionic cellulose polymer have been reported. OBJECTIVE: To report a case of contact urticaria from CMC in chalk, with possible cross-reaction to methyl hydroxyethylcellulose (MHEC). METHOD: Patch tests with readings at 48 and 96 hours were performed with the North American Contact Dermatitis Group standard series and benzisothiazolinone. Open and prick tests with readings after 30 minutes were performed with two brands of chalk as well as with various petrolatum and aqueous dilutions of CMC, MHEC, oleic acid, and calcium carbonate. RESULTS: The patient developed strong urticarial reactions during open tests with both powdered chalks and had milder reactions to the open test with CMC 10% aqueous (aq) and to prick testing with CMC 0.1% aq. No reaction to MHEC or any of the other ingredients of the chalks was observed. No relevant delayed reaction was noted. CONCLUSION: CMC can cause contact urticaria. It remains unclear why our patient reacted more strongly to the chalk than to CMC itself. We speculate that the abrasive nature of the chalk enhances the cutaneous penetration of CMC or that calcium carbonate, the main ingredient of the chalk, acts as an adjuvant. It is also possible that CMC and MHEC cross-react and that our negative results with MHEC may be due to improper testing technique or concentrations.

Adolescent↗

Cross-reactions among parabens, para-phenylenediamine, and benzocaine: a retrospective analysis of patch testing.

BACKGROUND: Parabens are alkyl ester derivatives of para-hydroxybenzoic acid and are the most commonly used preservatives in the cosmetic industry. Cross-reactions with para-amino compounds, namely, benzocaine and para-phenylenediamine (PPD), have been reported but are thought to be extremely rare. OBJECTIVE: To evaluate the rate of cross-reactivity between parabens, PPD, and benzocaine in a population of patients patch-tested in a hospital-based contact dermatitis clinic. METHODS: A retrospective analysis of 4,368 patients consecutively patch-tested between July 1989 and June 2005. RESULTS: Our study demonstrated that the rate of cross-reactions to parabens in PPD- and benzocaine-positive patients combined is 2%. CONCLUSION: This cross-reaction rate is significant in the tested population but still falls within the previously reported rates of sensitivity to parabens in the general population (0 to 3.5%).

Anesthetics, Local↗

Dermatologic surgery practice and skin cancer treatment in Canada: results of a national survey.

BACKGROUND: Although traditionally considered a medical subspecialty, dermatology has rapidly evolved over the past two decades to encompass a wide variety of cutaneous surgical procedures. OBJECTIVE: The study was carried out to evaluate the status of dermatologic surgery practice and skin cancer treatment in Canada. METHODS: In 2003, 550 practicing Canadian dermatologists were surveyed. RESULTS: Two hundred fifty-one dermatologists responded to the questionnaire, with the majority practicing in an urban part-time academic, part-time private setting. Statistics are presented on the types and demographics of dermatosurgical and cosmetic procedures performed, as well as on the specific dermatosurgical therapies used in the treatment of various cutaneous malignancies. CONCLUSIONS: The survey provides a current picture of dermatologic surgery practice and skin cancer treatment in Canada. The data suggest that Canadian dermatologists are further embracing surgical and cosmetic procedures.

Adult↗

Hypersensitivity to preservatives.

Preservatives are biocidal chemicals added to cosmetics, topical medicaments, consumer goods, foods, and industrial products to protect them against microbial spoilage and to protect the consumer against infection. The ideal preservative, both effective and devoid of irritant or sensitizing potential, is still to be discovered. The present paper reviews the most important classes of preservatives, namely parabens, formaldehyde-releasers, and isothiazolinones. The author also discusses newer agents such as Euxyl K 400 and isopropynyl butylcarbamate. Each preservative is described in terms of chemical and physical characteristics, antimicrobial efficacy, exposure, cutaneous adverse reactions, patch testing concentrations, patterns of cross-reactions, and reported rates of sensitization. The history of preservatives goes back to the 1930s, and ironically, the parabens, which the industry has sought to replace with "safer" alternatives, are still the most frequently used biocides in cosmetics and appear to be far less sensitizing than most of the newer agents.

Carbamates↗

Allergic contact dermatitis from cocamidopropyl betaine, cocamidoamine, 3-(dimethylamino)propylamine, and oleamidopropyl dimethylamine: co-reactions or cross-reactions?

We present the case of a patient with facial dermatitis caused by sensitization to cocamidopropyl betaine. The patient also had positive patch-test reactions to cocamidoamine, 3-(dimethylamino)propylamine, and oleamidopropyl dimethylamine. The presence of 3-(dimethylamino)propylamine as an impurity in all of these substances can be hypothesized to explain these simultaneous reactions.

Adult↗

Allergic contact dermatitis from isocyanates among sculptors.

Allergic contact dermatitis from isocyanates is rare. We present the cases of two sculptors who developed a dermatitis from polyurethane sculpting materials. The patients reacted to diphenylmethane diisocyanate and isophorone diisocyanate. One of the patients had positive patch-test reactions to 1,6-hexamethylene diisocyanate and toluene diisocyanate as well. The patients also exhibited a sensitivity to diaminodiphenylmethane, an amine that has been reported in other cases of isocyanate sensitivity.

Adult↗

North American Contact Dermatitis Group patch-test results, 2001-2002 study period.

BACKGROUND: Allergic contact dermatitis is a significant cause of cutaneous disease affecting many individuals in the home and at the workplace. Patch testing is the most worthwhile diagnostic tool for the evaluation of patients with suspected allergic contact dermatitis. OBJECTIVE: This study reports the results of patch testing from January 1, 2001, to December 31, 2002, by the North American Contact Dermatitis Group (NACDG). METHODS: Patients were tested with an extended screening series of 65 allergens. A standardized patch-testing technique was used. Data from these patients were recorded on a standardized computer entry form and analyzed. RESULTS: Sixty-five allergens were tested on 4,913 patients. The top 10 allergens remain the same in this study period as in the 1999-2000 study period: nickel sulfate (16.7%), neomycin (11.6%), Myroxilon pereirae (balsam of Peru) (11.6%), fragrance mix (10.4%), thimerosal (10.2%), sodium gold thiosulfate (10.2%), quaternium-15 (9.3%), formaldehyde (8.4%), bacitracin (7.9%), and cobalt chloride (7.4%). Of the 4,913 patients tested, 69% had at least one positive allergic patch-test reaction. Of all patients, 15.8% had occupation-related dermatitis; 15.4% were determined to have irritant contact dermatitis, and 11.1% of the 15.4% had a relevant reaction to an occupational irritant. Of all patients tested, 16.7% had a relevant reaction to an allergen not in the NACDG standard series, and 5.5% had a relevant reaction to an occupational allergen not in the standard series. CONCLUSION: Our findings once again reinforce the need for a more comprehensive group of diagnostic allergens than those found in the standard screening kits. The usefulness of patch testing is enhanced when a greater number of allergens are tested, especially nonstandard allergens occupationally encountered.

Adolescent↗

Patch testing with thimerosal in a Canadian center: an 11-year experience.

BACKGROUND: Thimerosal has been used for decades as an antiseptic, a disinfectant, and a preservative in various consumer products. It is also a notoriously frequent contact allergen, but the significance of positive patch-test reactions has been debated over the past decade. OBJECTIVE: The aim of this study was to assess the prevalence and relevance of positive patch-test reactions to thimerosal in a large Canadian center and to compare our results with those of previous publications. METHODS: A retrospective analysis of data collected over the course of 11 years in the contact dermatitis clinic of a university hospital was performed. RESULTS: Of 2252 subjects patch-tested for thimerosal, positive reactions were observed in 102 individuals (4.53%), placing thimerosal as the fifth most common allergen in our practice. The sensitization rate was equivalent between the patients who underwent aimed patch testing and those who were routinely tested for reaction to thimerosal when this allergen was included in our standard patch-testing series 8 years into the study. There was an increased incidence of thimerosal sensitization in chemists and laboratory technicians, as well as in health care workers, including medical doctors, registered nurses, dentists, and dental assistants. While eight reactions were deemed possibly relevant, in none of the cases was it possible to definitely establish the relevance of positive reactions to thimerosal, either because the presence of this allergen could not be verified in patients' products or because patch testing with these products gave negative results. CONCLUSION: In agreement with previous reports, we conclude that even though positive reactions to thimerosal are frequent, very few seem to be clinically relevant.

Adolescent↗

Cross-reactivity among epoxy acrylates and bisphenol F epoxy resins in patients with bisphenol A epoxy resin sensitivity.

OBJECTIVE: The study's objective was 2-fold: first, to evaluate the potential cross-reactivity between Bis-A epoxy resins and epoxy acrylates and second, to study the cross reactivity between Bis-A epoxy resins and newer Bis-F epoxy resins in patients with allergic contact dermatitis to epoxy resins and had positive patch test to the standard epoxy resin based on bisphenol A. METHODS: Forty-one patients were patch tested to 23 chemicals including epoxy acrylates, Bis-A epoxy resins, and Bis-F epoxy resins, as well as reactive diluents and nonbisphenol epoxy resins. Questions concerning exposure to epoxy resins, occupational history, and problems with dental work were completed. RESULTS: All patients included in the study had positive reactions to the standard Bis-A epoxy resin. Twenty percent (8 of 41) of the patients reacted to at least one of the epoxy acrylates; the most common reaction was to Bis-GMA. Five of 8 patients who reacted to the epoxy acrylates had dental work, but only one patient had problems from her dental work. Six of 8 patients (75%) who reacted to epoxy resins and epoxy acrylates did not react to aliphatic acrylates. Thirty-two percent (13 of 41) reacted to tosylamide epoxy resin, and none reacted to triglycidyl isocyanurate resin. In addition, all patients (100%) had positive reactions to at least one of the Bis-F epoxy resins that were tested. CONCLUSIONS: Most patients with sensitivity to Bis-A epoxy resins do not cross-react with epoxy acrylates. Patients with positive patch test reactions to epoxy acrylates used in dentistry usually do not have symptoms from their dental work. To our knowledge, this is the largest series of patients with sensitivity to the standard Bis-A epoxy resin that have been patch tested with the more recently introduced Bis-F epoxy resins. There is significant cross-reactivity between Bis-A and Bis-F epoxy resins, which can be explained by their structural similarity.

Adult↗