Hand eczema in children referred for patch testing: North American Contact Dermatitis Group Data, 2000-2016.

BACKGROUND: Little is known about the aetiologies and relevant allergens in paediatric patients with hand eczema (HE). OBJECTIVES: To characterize the aetiologies and determine the proportion of positive and currently relevant allergens in children/adolescents (age < 18 years) with HE referred for patch testing. METHODS: A retrospective analysis (2000-2016) of North American Contact Dermatitis Group data was performed. RESULTS: Of 1634 paediatric patients, 237 (14·5%) had involvement of the hands. Final physician diagnoses included allergic contact dermatitis (49·4%), atopic dermatitis (37·1%) and irritant contact dermatitis (16·9%). In multivariable logistic regression models, employment was the only association with increased odds of any HE or primary HE. Children with HE vs. those without HE had similar proportions of positive patch tests (56·1% vs. 61·7%; χ2 -test, P = 0·11). The five most common currently relevant allergens were nickel, methylisothiazolinone, propylene glycol, decyl glucoside and lanolin. In multivariable logistic regression models of the top 20 relevant allergens, HE was associated with significantly higher odds of currently relevant reactions to lanolin, quaternium-15, Compositae mix, thiuram mix, 2-mercaptobenzathiazole and colophony. The allergens with the highest mean significance-prevalence index number were methylisothiazolinone, carba mix, thiuram mix, nickel and methylchloroisothiazolinone/methylisothiazolinone. CONCLUSIONS: Children with HE who were referred for patch testing had a high proportion of positive patch tests, which was similar to the proportion found in children without HE. Children with HE had a distinct and fairly narrow profile of currently relevant allergens.

Investigating epidemiologic trends and the geographic distribution of patients with anal squamous cell carcinoma throughout Canada.

Background: Anal cancer is a rare disease, constituting 0.5% of new cancer cases in the United States. The most common subtype is squamous cell carcinoma (scc). Studies in several developed nations have reported on an increasing incidence of anal cancer in recent decades, and various risk factors pertaining to the pathogenesis of the disease have been identified, including infection with the human papillomavirus, tobacco use, and immunosuppression. The epidemiology and distribution of anal scc throughout Canada remain poorly understood, however. Methods: Using 3 population-based cancer registries, a retrospective analysis of demographic data across Canada for 1992-2010 was performed. The incidence and mortality for anal scc was examined at the levels of provinces, cities, and the forward sortation area (FSA) component (first 3 characters) of postal codes. Results: During 1992-2010, 3720 individuals were diagnosed with anal scc in Canada; 64% were women. The overall national incidence rate was 6.3 cases per million population per year, with an average age at diagnosis of 60.4 years. The incidence increased over time, with significantly higher incidence rates documented in British Columbia and Nova Scotia (9.3 cases per million population each). Closer examination revealed clustering of cases in various urban centres and self-identified lgbtq communities in Toronto, Montreal, and Vancouver. Discussion: This study provides, for the first time, a comprehensive analysis of the burden of anal scc in Canada, identifying susceptible populations and shedding light onto novel avenues of research to lower the incidence of anal cancer throughout the country.

Epidemiology of adult and pediatric Burkitt lymphoma in Canada: sequelae of the HIV epidemic.

Background: Although the pathogenesis and epidemiology of endemic Burkitt lymphoma (bl) have been extensively studied, the epidemiologic landscape of sporadic and immunodeficiency-associated bl in North America remains poorly understood. Methods: We used 3 distinct population-based cancer registries to retrospectively study bl incidence and mortality in Canada. Data for patient sex; age at the time of diagnosis; and reporting province, city, and forward sortation area (fsa, the first three characters of a postal code) were analyzed. Results: During 1992-2010, 1420 patients with bl in Canada were identified (incidence rate: 2.40 cases per million patient-years), of which 71.1% were male patients. Mean age at diagnosis was 55.5 ± 20.8 years. A bimodal incidence by age distribution was seen in both sexes, with pediatric- and adult-onset peaks. An analysis based on fsas identified select communities with statistically higher rates of adult bl. Several of those fsas were located within the 3 major metropolitan areas (Montreal, Vancouver, Toronto) and within self-identified lgbtq communities. The fsas with a higher socioeconomic status score were associated with lower rates of bl. Conclusions: Current results highlight the geographic and historic pattern of bl in Canada. The human immunodeficiency virus remains an important risk factor for adult bl.

Incidence and mortality trends and geographic patterns of follicular lymphoma in Canada.

Background: Follicular lymphoma (fl) is the most common indolent lymphoma and the 2nd most common non-Hodgkin lymphoma, accounting for 10%-20% of all lymphomas in the Western world. Epidemiologic and geographic trends of fl in Canada have not been investigated. Our study's objective was to analyze incidence and mortality rates and the geographic distribution of fl patients in Canada for 1992-2010. Methods: Demographic and geographic patient data for fl cases were obtained using the Canadian Cancer Registry, the Registre québécois du cancer, and the Canadian Vital Statistics database. Incidence and mortality rates and 95% confidence intervals were calculated per year and per geographic area. Rates were plotted using linear regression models to assess trends over time. Overall data were mapped using Microsoft Excel mapping software (Redmond, WA, U.S.A.) to identify case clusters across Canada. Results: Approximately 22,625 patients were diagnosed with fl during 1992-2010. The age-standardized incidence rate of this malignancy in Canada was 38.3 cases per million individuals per year. Geographic analysis demonstrated that a number of Maritime provinces and Manitoba had the highest incidence rates, and that the provinces of Nova Scotia and Quebec had the highest mortality rates in the nation. Regional data demonstrated clustering of fl within cities or regions with high herbicide use, primary mining, and a strong manufacturing presence. Conclusions: Our study provides a comprehensive overview of the fl burden and its geographic distribution in Canada. Regional clustering of this disease in concentrated industrial zones strongly suggests that multiple environmental factors might play a crucial role in the development of this lymphoma.

Evaluation of herpes simplex virus infection morbidity and mortality in pancreas and kidney-pancreas transplant recipients.

BACKGROUND: Infections remain a major cause of morbidity and mortality in solid organ transplant recipients. An increased risk of up to 50% of herpes simplex virus (HSV) reactivation in transplant recipients in the first months posttransplantation was well-documented during the pre-cytomegalovirus prophylaxis era. Previous reports suggest that these patients are likely to experience a more aggressive disease course and a higher rate of acyclovir-resistant HSV. No data currently exist regarding the course of HSV infection in pancreas or pancreas-kidney transplant (PKT) recipients. The goal of this study was to evaluate the incidence and severity of HSV infections in pancreas transplant and PKT recipients. STUDY DESIGN: We analyzed a transplant patient database of the Royal Victoria Hospital to identify 137 pancreas transplant or PKT performed between January 1999 and October 2010. A retrospective chart review was subsequently performed to evaluate the incidence and severity of herpetic infections post transplantation. RESULTS: Our findings show that the incidence of HSV infection in our patients was approximately 10% (10/98 cases). The majority of infections (80%) took place within the first 2 years after the transplantation. Most patients (90%) experienced a uniform, mild disease course and responded well to treatment. One patient died of an unrelated cause. Six patients were treated in hospital with a mean stay of 12.3 ± 6.35 days. The initial immunosuppressive regimen remained unchanged for half of the affected patients. None of our patients developed a drug-resistant HSV. CONCLUSION: These findings are intriguing and warrant a larger, multicenter, prospective study. Most important, they suggest that the new incidence of HSV reactivation is now much lower in the "cytomegalovirus prophylaxis era" and that with timely diagnosis and proper treatment most patients recover well from their HSV infections and respond to the current treatment regimens.

Evaluation of varicella zoster virus infection morbidity and mortality in pancreas and kidney-pancreas transplant recipients.

BACKGROUND: Solid organ transplant recipients are at increased risk of infection due to chronic immunosuppression. The incidence of varicella zoster virus (VZV) infection is known to be increased in these patients compared with the immunocompetent population. Previous reports suggested that these patients are likely to experience a morbid disease course. Few data currently exist on the course of VZV infections in pancreas or pancreas plus kidney (PK) transplant recipients. OBJECTIVE: The goal of this study was to evaluate the incidence and severity of VZV infections in pancreas or PK recipients. STUDY DESIGN: We analyzed the transplantation patient database of the Royal Victoria Hospital, identifying 137 pancreas or PK transplantation procedures performed between January 1999 and October 2010, among which we included 98 patients in the study. We subsequently performed a retrospective chart review to evaluate the incidence and severity of VZV infections posttransplantation. RESULTS: Our analysis revealed that 11/98 patients developed VZV infections. The majority of infections (~90.9%) occurred within the first 5 years. Most patients (63.6%) were treated on an outpatient basis, whereas only 4 (36.4%) were hospitalized with a mean hospital stay of 9.5 ± 8.42 days. The initial immunosuppressive regimen remained unchanged for the majority of patients. All patients experienced a mild disease course without intensive care unit admission or death. Only 3 patients (27.3%) developed postherpetic neuralgia. CONCLUSION: These findings suggest that with timely diagnosis and proper treatment, most patients recover well from a VZV infection.

Occupational contact allergens: are they also associated with occupational asthma?

BACKGROUND: Workplace exposures that can potentially cause both allergic occupational contact dermatitis (AOCD) and occupational asthma (OA) are not clearly identified. METHODS: Occupational contact allergens (OCAs) were identified using North American Contact Dermatitis Group (NACDG) data. Reference documents and systematic reviews were used to determine whether each OCA had been reported to potentially cause OA. The presence or absence of a sensitizer notation in occupational hygiene reference documents was also examined. RESULTS: The 10 most common OCAs were: epoxy resin*, thiuram, carba mix, nickel sulfate*, cobalt chloride*, potassium dichromate*, glyceryl thioglycolate, p-phenylenediamine*, formaldehyde* and glutaraldehyde*. Seven (indicated by *) were determined to be possible causes of OA. Information on sensitizing potential from OH reference materials contained conflicting information. CONCLUSIONS: Several common OCAs can also potentially cause OA. Inhalation and dermal exposures to these agents should be controlled and both OA and AOCD should be considered as possible health outcomes. Increased consistency in sensitizer notations is needed.

[Interpretation and relevance of patch testing: false-positive and false-negative test reactions, compound allergy, cross-sensitivity]. / Interprétation et pertinence des patch-tests : faux-positifs et faux-négatifs, allergies composées, allergies croisées.

This chapter reviews pitfalls and mistakes in patch testing. Most sources of false-positive and false-negative reactions are indicated and analysed. Cross-sensitivity among allergens is discussed and compound allergy is debated. Keys for establishing relevance are indicated, for a better reading and interpretation of patch testing by practitioners (trainees or experienced dermatologists).

Psoriasis of the nail: anatomy, pathology, clinical presentation, and a review of the literature on therapy

Psoriasis is a chronic skin disease that affects millions of people throughout the world. Even though cutaneous signs and symptoms are the most common clinical manifestations, the nails can be involved in up to 50% of cases, and their involvement remains an important yet often overlooked aspect of the disease. There is a broad spectrum of nail dystrophies associated with psoriasis, ranging from the common pitting and loosening of the nail plate to the less frequent discoloration and splinter hemorrhages seen in the nail bed. This article discusses the normal anatomy and embryology of the nail unit as well as the current understanding of the pathogenesis of the disease. It also provides an extensive review of the existing literature with respect to psoriatic nail therapy. Although there have been many recent advances in the treatment of the cutaneous form of the disease-most notably in the field of immunotherapies-the options for nail psoriasis are far more limited. While a number of treatment alternatives currently exist for nail disease, the general paucity of clear evidence regarding these choices often makes it difficult to select the most efficient, safe, and optimal treatment for the patient. Even though the current literature has shown some support for the use of topical, intralesional, radiation, systemic, and combination therapies for nail psoriasis, the available studies lack sufficient power to extrapolate a standardized therapeutic regimen. Therefore, until better-documented evidence validating the treatment options emerges within the literature, clinicians and patients are left with a vague and relatively unproven approach to psoriatic nail disease.

Occupational contact dermatitis to textile dyes in airline personnel.

BACKGROUND: Reports of textile dye allergic contact dermatitis are becoming frequent in the literature. Occupational exposure to textile dyes has been reported, but less frequently. OBJECTIVE: To report 2 cases of allergic contact dermatitis to Disperse Blue dyes 106 and 124 occurring in airline personnel. METHODS: The patients were patch tested to the European or North American standard series, a textile dye series, and 1 patient was tested with pieces of textile from an airplane seat. RESULTS: Patch testing elicited in both patients a 2+ reaction to Disperse Blue dyes 106 and 124, and a 1+ reaction to paraphenylenediamine in one patient. CONCLUSION: We describe 2 cases of occupational textile dye allergy occurring in airline personnel. Both cases showed the utility of Disperse Blue dyes 106 and 124 to serve as the screening allergens for textile dermatitis. Mandatory uniforms might be an occupational hazard in certain professions.

Allergic contact dermatitis to tea tree oil with erythema multiforme-like id reaction.

The commercial production of tea tree oil, extracted from Melaleuca alternifolia Cheel, has considerably increased over the past 15 years in response to a strong demand for natural remedies and aromatic substances. The number of case reports that describe allergic contact dermatitis (ACD) to this essential oil is also on the rise. We report an additional case of ACD to tea tree oil that presented with an extensive erythema multiforme-like reaction. A skin biopsy was performed from a targetlike lesion distant from the site of the initial dermatitis. The patient was treated with systemic and topical corticosteroids. Five months later, he was patch tested to the North American standard series, to his own tea tree oil, to a fresh batch of tea tree oil, and to some related allergens. The skin biopsy showed a spongiotic dermatitis without histological features of erythema multiforme. Patch testing elicited a 3+ reaction to old, oxidized tea tree oil, a 2+ reaction to fresh tea tree oil, a 2+ reaction to colophony, a 1+ reaction to abitol, and a 1+ reaction to balsam of Peru. We believe this is the first report of erythema multiforme-like reaction secondary to ACD from tea tree oil. Other interesting features are the stronger reaction to oxidized than to fresh tea tree oil, and concomitant reactivity to colophony, abitol, and balsam of Peru.

Allergic contact dermatitis to epoxy resin in microscopy immersion oil: cases from Canada.

The presence of epoxy resin in a reformulated immersion oil for microscopy has caused an epidemic of occupational contact dermatitis in laboratory technicians from some European centers. We report 6 additional cases, the mode of presentation of which was similar to the European patients. All patients were patch tested to the undiluted oil, and some were tested to the European or North American standard series and to an extensive series of glues and adhesives allergens. At 96 hours, all 6 patients displayed a strong 2+ to 3+ reaction to the undiluted oil. Two patients were not further tested, but in the remaining 4, positive reactions were seen to epoxy resin from the standard tray. One patient reacted to cycloaliphatic epoxy resin, and 2 displayed positive tests to the reactive diluents phenyl glycidyl ether and cresyl glycidyl ether. These further cases confirm the strong sensitizing properties of this particular immersion oil. The product, manufactured by Leica Microsystems (Wetzlar, Germany), since has been withdrawn from sale.

Interferon-induced cutaneous necrosis.

BACKGROUND: Due to advances in recombinant DNA technology, interferons are now readily available and are frequently used in all branches of medicine. These potent biologic response modifiers carry a number of systemic and local side effects. These cytokines are usually administered subcutaneously, and recent studies have described the occurrence of inflammation or necrosis at the site of injection. OBJECTIVE: We report a case of cutaneous necrosis at the sites of interferon injections in a 35-year-old man treated for chronic myeloid leukemia with high, daily doses of interferon alfa. In addition, we review the existing literature on interferon-induced cutaneous necrosis and discuss preventive strategies. CONCLUSION: Cutaneous inflammation or necrosis at interferon injection sites is not uncommon. Although interferon beta-1b is most commonly responsible for this complication, it is now increasingly reported with interferon alfa. It appears to be secondary to the proinflammatory effects of these cytokines or to their unmasking of a subtle hypercoagulable state.

Phytodermatitis.

BACKGROUND: Most dermatologists can recognize the classic patterns of presentation of plant contact dermatitis; however, few can recognize the offending plants or know the name and chemical structure of the allergens or irritants that they contain. OBJECTIVE: Five basic clinical patterns of phytodermatitis are reviewed: 1) allergic phytodermatitis, 2) photophytodermatitis, 3) irritant contact dermatitis, 4) pharmacologic injury, and 5) mechanical injury. The plants responsible for each pattern are presented by families, according to current scientific taxonomy. The chemical structure of the offending substances is described, and principles of investigation, prevention, and treatment are outlined. CONCLUSIONS: Plant contact dermatitis remains an extremely vast and complex topic. Exotic plants and woods are now present in our gardens and homes. The newfound interest in aromatherapy, phytotherapy, and so-called "natural" therapies is the cause of a tremendous increase in exposure to plant products and extracts. This is responsible for the appearance of atypical patterns of plant contact dermatitis with which the practising dermatologist must become familiar.

Pseudoporphyria induced by propionic acid derivatives.

BACKGROUND: Pseudoporphyria is a photosensitive bullous skin disease that is distinguished from porphyria cutanea tarda (PCT) by its normal porphyrin profile. Drugs are a major cause of this disease, and the list of culprits is continually expanding. Nonsteroidal antiinflammatory agents (NSAIDs), especially naproxen and other propionic acid derivatives, appear to be the most common offenders. OBJECTIVE: The study was carried out to increase awareness about the etiology and characteristic features of pseudoporphyria. METHODS: We report two cases of pseudoporphyria caused by naproxen and oxaprozin. We review the current English language literature on this entity and discuss its clinical features, histology, ultrastructure, etiology, and pathophysiology. RESULTS: A 44-year-old man taking naproxen for chronic low back pain and a 20-year-old woman on oxaprozin for rheumatoid arthritis presented with tense bullae and cutaneous fragility on the face and the back of the hands. In both, skin biopsy showed a cell-poor subepidermal vesicle with festooning of the dermal papillae. Direct immunofluorescence revealed staining at the dermal-epidermal junction and around blood vessels with IgG in the first case and with IgG, IgA, and fibrin in the second case. Urine collections and serum samples yielded normal levels of uro- and coproporphyrins. CONCLUSIONS: Most cases of pseudoporphyria are drug-induced. Naproxen, the most common offender, has been associated with a dimorphic clinical pattern: a PCT-like presentation and one simulating erythropoietic protoporphyria in the pediatric population. Other NSAIDs of the propionic acid family can also cause pseudoporphyria.