The Penetration of Chromium: An Up-To-Date 0.5% Potassium Dichromate Vehicle Comparison.

BACKGROUND: Chromium (Cr) contact allergy is frequent in many industrialized countries. The knowledge of the factors that can influence percutaneous penetration is very important assessing the risk of human exposure. OBJECTIVE: The aim of the study was to compare the concentration of Cr in various skin layers using 2 different vehicles. METHODS: Full-thickness (approximately 1 mm) porcine ear skin was mounted in Franz-type diffusion cells. Duplicate potassium dichromate preparations in 0.5% petrolatum (pet) and 0.5% in aqua (aq) were applied to the donor compartment facing the epidermis for 24 hours. After the experiment, the porcine skin samples were cut with a microtome. All samples were analyzed for total Cr concentration by inductively coupled plasma sector field mass spectrometry. The limit of detection was 0.001 µg/cm3. RESULTS: Chromium was detected in both recipient phases. The distribution of Cr in the skin is similar for pet and aq preparations, but the concentration of Cr detected in the skin was almost 2 times lower for pet comparing aq preparations. CONCLUSIONS: Both vehicles were suitable for penetrating the skin. Less Cr is found in the skin when pet is used as a vehicle. Acid wipe sampling and finger immersion test results might be false-negative for Cr in occupations involving contact with Cr salts in aq solutions.

Pattern of contact sensitization in patients with and without atopic dermatitis in an Asian dermatology center.

BACKGROUND: Although the traditional understanding is that contact sensitization is less frequent in patients with atopic dermatitis (AD), recent studies have shown similar or higher rates of positive patch-test results in AD patients. OBJECTIVES: We sought to characterise the pattern of contact sensitization in patients with and without AD and evaluate the association between AD and contact sensitization. METHOD: This was a single-center, 10-year retrospective review of patients who underwent patch testing between 2007 and 2017. RESULTS: There were 4903 patients (male-to-female ratio = 1:1.4; mean age 40.1 years) included. About half (2499, 51.0%) of all patients developed at least one positive reaction. The top five frequent reactions were to nickel sulfate (45.4%), potassium dichromate (16.0%), p-phenylenediamine (13.4%), Myroxylon pereirae (11.8%), and fragrance mix I (11.2%). The overall prevalence of contact sensitization was not significantly different between patients with or without AD. Patients with AD were less likely to develop contact allergies to budesonide and thiuram mix, and more likely to develop contact allergies to potassium dichromate. CONCLUSIONS: Contact sensitization was detected in 50% of patients who were patch tested. Nickel sulfate was the most frequently sensitizing allergen. The prevalence of contact allergies in atopic patients is comparable to that in non-atopic patients.

Contact Dermatitis in Construction Workers in Northeastern Italian Patch Test Database Between 1996 and 2016.

BACKGROUND: Contact dermatitis in construction workers (CWs) is frequent due to the widespread exposure to sensitizing substances and irritating agents and the wet and cold working conditions. OBJECTIVE: Our objectives were to evaluate contact dermatitis characteristics among CWs who underwent patch test in northeastern Italy and to identify related allergens. METHODS: Seven hundred ninety-five CWs were studied and their data were compared to 2.099 male white-collar workers. The associations between patch test results and occupations were assessed by multivariate logistic regression analysis. Incidence data were calculated from 1996 to 2016. RESULTS: CWs with confirmed occupational dermatitis presented an increased risk to be sensitized to potassium dichromate [OR 3.1 (95%IC 2.0-4.8)], to thiurams [OR 8 .6 (95%IC 4.0-18.4)], and to epoxy resins [OR 12.7 (95%IC 6.1-26.4)]. Sensitization to chromate decreased significantly after 2004, following EU regulation of chromate content in concrete, while sensitization to epoxy resins and thiurams increased. The overall incidence of occupational contact dermatitis in CWs decreased significantly. CONCLUSION: Our study demonstrated the effectiveness of EU regulations in reducing chromate sensitization in CWs and the overall incidence of occupational contact dermatitis. However, sensitization to other haptens is increasing, though improvement of protective measures is compulsory.

Alterations in mitochondrial homeostasis in a potassium dichromate model of acute kidney injury and their mitigation by curcumin.

Curcumin has protective effects in several acute kidney injury models, including that induced by potassium dichromate (K2Cr2O7). The protective effect of curcumin in this experimental model has been associated to the preservation of mitochondrial bioenergetics. This study is aimed at evaluating whether or not curcumin's protective effect in mitochondrial bioenergetics is related to the modulation of mitochondrial dynamics and biogenesis. Wistar rats were treated with a single subcutaneous dose of K2Cr2O7 (12.5 mg/kg) or received curcumin (400 mg/kg/day) by oral gavage 10 days before and one day after the K2Cr2O7 injection. K2Cr2O7 induced kidney dysfunction and increased mitochondrial hydrogen peroxide production, while decreasing the respiration directly attributable to oxidative phosphorylation and mitochondrial membrane potential. In mitochondria, K2Cr2O7 increased fission and reduced fusion. Structural analysis of mitochondria in the proximal tubular cells corroborated their fragmentation and loss of crests' integrity. Regarding mitochondrial biogenesis, K2Cr2O7 decreased peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) levels. Conversely, curcumin treatment mitigated the aforementioned alterations and increased the expression of the mitochondrial transcription factor A (TFAM). Taken together, our results suggest that curcumin can protect against renal injury by modulating mitochondrial homeostasis, mitigating alterations in bioenergetics and dynamics, possibly by stimulating mitochondrial biogenesis.

Trend of relevant contact allergens of the feet in Spain over a period of 10 years.

INTRODUCTION: Allergic contact dermatitis (ACD) of the feet accounts for approximately 10% of all patch tested patients. OBJECTIVE: To study the clinical profile of patients with feet dermatitis and relevant contact allergens in Spain over a 10-year period. METHODS: Retrospective observational study of patients with suspected ACD from the GEIDAC (Spanish Research Group on Contact Dermatitis and Cutaneous Allergy) baseline series from eight hospitals in Spain between 2004 and 2014. The clinical data collected from each patient were age, sex, occupation, history of atopic dermatitis, and eczema location. RESULTS: A total of 450 cases clinically presented dermatitis affecting the feet; of these, 41% of were males and 5.6% were suspected to be of occupational origin. As much as 47% were diagnosed with ACD, 20% with atopic dermatitis/dyshidrotic eczema, and 5% with psoriasis. The "feet group" included statistically significantly more females in the age range of 21 to 60 years. The most frequent relevant contact allergens were potassium dichromate, cobalt(II) chloride, p-tert-butylphenol formaldehyde resin, mercapto mix, and mercaptobenzothiazole. CONCLUSIONS: ACD is the most frequent clinical diagnosis of feet dermatitis in our series. The most frequent allergens are similar to those published in other series of foot ACD in Europe and the trend has not changed in the studied decade.

Foot Eczema in a Skin Allergy Unit: Retrospective Study of 13 Years. / Eczema en los pies en una consulta de alergia cutánea: estudio retrospectivo de 13 años.

INTRODUCTION: Foot eczema is a common complaint encountered by skin allergists. OBJECTIVE: To study a series of patients with foot eczema who underwent patch testing and describe their demographic profile, diagnoses, and the main allergens involved. MATERIAL AND METHODS: Cross-sectional observational study of all patients tested with the standard Spanish patch test series at a dermatology department over a period of 13 years (2004-2016). We studied patch test results and definitive diagnoses by comparing different subgroups of patients with foot eczema. RESULTS: Of the 3,265 patients included in the study, 308 (9.4%) had foot eczema, 176 (57.9%) had foot eczema only and 132 (42.1%) had concomitant foot and hand eczema. Positive patch test results were more common in patients with foot eczema only (positivity rate of 61.5% vs. 53.4% for foot and hand eczema). In the subgroup of patients with concomitant foot and hand involvement, patients aged under 18 years had a lower rate of positive results (51.3% vs. 64.6% for patients >18 years). Potassium dichromate was the most common allergen with current relevance in all subgroups. The main diagnosis in patients with foot involvement only was allergic contact dermatitis (49.1%). In the subgroup of patients with concomitant hand and foot eczema, the main diagnoses were psoriasis in adults (33.6%) and atopic dermatitis in patients aged under 18 years (60.0%). CONCLUSION: Patch tests are a very useful diagnostic tool for patients with foot eczema with or without concomitant hand involvement.

Delayed hypersensitivity to palladium dichloride: 15-year retrospective study in a skin allergy unit.

BACKGROUND: Metal allergies are the most frequent causes of allergic contact dermatitis. Although the use of palladium is increasing, it is not included in any baseline series. OBJECTIVE: To assess the prevalence of hypersensitivity to palladium and to describe the clinical and demographic characteristics of patients who are sensitized to palladium dichloride (PdCl2 ). METHODS: A single-centre, retrospective study of 15 years of patch testing with the Spanish baseline series supplemented with PdCl2 2% pet. was performed. We collected clinical and demographic data and data on co-sensitization among the metals studied, and we compared patients who were sensitized to palladium, with or without co-sensitization to nickel, with the rest of the study population. RESULTS: Among the 3678 included patients, 730 (19.9%) were sensitized to nickel sulfate. The prevalence of sensitization to PdCl2 (n = 316, 8.6%) was higher than the prevalence of sensitization to potassium dichromate (n = 240, 6.5%) and similar to the prevalence of sensitization to cobalt chloride (n = 353, 9.6%). Only 26 (8.2%) of the patients sensitized to palladium were not co-sensitized to nickel. The percentage of men and patients aged ≥40 years was higher in this subgroup than in the patients with nickel co-sensitization. CONCLUSIONS: Given the high prevalence of hypersensitivity to PdCl2 , this metal salt should be included in the Spanish baseline series, notwithstanding the frequency of co-sensitization to nickel.

Sociodemographic and clinical profile of patients with occupational contact dermatitis seen at a work-related dermatology service, 2000 - 2014.

BACKGROUND: Occupational dermatoses are common, especially contact dermatitis. Epidemiological studies on these dermatoses are scarce in Brazil and they are necessary as part of the public policy to protect workers' health. OBJECTIVES: To identify sociodemographic and clinical profile of patients with occupational contact dermatitis seen between 2000 and 2014 at an occupational dermatology service. METHODS: It is a cross-sectional and retrospective study, based on information obtained from the service's database. RESULTS: Of 560 patients with conclusive patch test, 289 (46.9%) presented occupational dermatoses and 213 occupational contact dermatitis with predominance of the allergic type in relation to the irritative type (149:64 respectively). The odds of occupational dermatoses were higher among men and lower among patients aged 50 years or older and with higher level of education. Regarding the possibility of presenting occupational allergic contact dermatitis, only the gender variable was statistically significant. The professions most seen were cleaners, construction workers, painters, mechanics/metallurgists and cooks. The commonest allergens were nickel sulfate, potassium dichromate, cobalt chloride, carba-mix and formaldehyde. STUDY LIMITATIONS: The main limitations of this study are the fact that it was carried out in a tertiary service of occupational dermatoses and the lack of access to some allergens outside the patch test baseline series. CONCLUSIONS: It was possible to identify the sociodemographic and clinical profile of patients with suspected occupational contact dermatitis seen at the Service, beyond the professional groups and allergens related to a high risk of occupational contact dermatitis in this population.

Sociodemographic and clinical profile of patients with occupational contact dermatitis seen at a work-related dermatology service, 2000 - 2014

Abstract: BACKGROUND: Occupational dermatoses are common, especially contact dermatitis. Epidemiological studies on these dermatoses are scarce in Brazil and they are necessary as part of the public policy to protect workers' health. OBJECTIVES: To identify sociodemographic and clinical profile of patients with occupational contact dermatitis seen between 2000 and 2014 at an occupational dermatology service. METHODS: It is a cross-sectional and retrospective study, based on information obtained from the service's database. RESULTS: Of 560 patients with conclusive patch test, 289 (46.9%) presented occupational dermatoses and 213 occupational contact dermatitis with predominance of the allergic type in relation to the irritative type (149:64 respectively). The odds of occupational dermatoses were higher among men and lower among patients aged 50 years or older and with higher level of education. Regarding the possibility of presenting occupational allergic contact dermatitis, only the gender variable was statistically significant. The professions most seen were cleaners, construction workers, painters, mechanics/metallurgists and cooks. The commonest allergens were nickel sulfate, potassium dichromate, cobalt chloride, carba-mix and formaldehyde. STUDY LIMITATIONS: The main limitations of this study are the fact that it was carried out in a tertiary service of occupational dermatoses and the lack of access to some allergens outside the patch test baseline series. CONCLUSIONS: It was possible to identify the sociodemographic and clinical profile of patients with suspected occupational contact dermatitis seen at the Service, beyond the professional groups and allergens related to a high risk of occupational contact dermatitis in this population.

Optimal dosage and early intervention of L-ascorbic acid inhibiting K2Cr2O7-induced renal tubular cell damage.

Chromium poisoning can cause renal failure and death. Chromium intoxication may be managed using L-ascorbic acid (vitamin C) therapy. However, the evidence supporting the effectiveness of this treatment is insufficient, and the mechanism of action has not been clarified in renal cells. In this study, our results showed that the optimal regimen of L-ascorbic acid therapy in human epithelial renal proximal tubule cells, HK-2 cells, was 30 µg/mL. Supplementation of L-ascorbic acid with 30 µg/mL and within 8 h of chromium intoxication (K2Cr2O7, Cr6+) was effective to inhibit renal tubular cell damage by blocking generation of free radicals, cell apoptosis, and autophagy. Intracellular chromium concentrations were estimated using electrothermal atomic absorption spectrometry. Treatment of L-ascorbic acid within 8 h of chromium intoxication significantly decreased the entry of chromium into the cells. Moreover, concomitant administration of L-ascorbic acid with repeatedly dosing at 8-hourly intervals had a better protective effect at lower concentration of L-ascorbic acid when compared to single dosing of L-ascorbic acid at an early time point of chromium intoxication. These findings might help physicians develop effective therapy strategies in renal failure.

Potential action of Rumex vesicarius (L.) against potassium dichromate and gentamicin induced nephrotoxicity in experimental rats.

To determine the ameliorative potential of the active fraction from different extracts of Rumex vesicarius against potassium dichromate and gentamicin induced nephrotoxicity in experimental rats and its possible mechanism of action. Both sex wistar rats were divided into 6 groups (n=6/group) were fed with a control, potassium dichromate and gentamicin supplemented with different extracts at the doses of 200 and 400mg/kg respectively. Oral administration of EERV offered a significant (p<0.01 and p<0.001) dose dependent protection against PD and GN induced nephrotoxicity. Potassium dichromate and gentamicin nephrotoxicity assessed in terms of body weight, kidney weight, creatinine, urea, uric acid, BUN, albumin and total protein. Thus the present study revealed that EERV phytochemical constituents play an important role in protection against kidney damage.

Comparing reliabilities of strip and conventional patch testing.

BACKGROUND: The standardized protocol for performing the strip patch test has proven to be valid, but evidence on its reliability is still missing. OBJECTIVE: To estimate the parallel-test reliability of the strip patch test as compared with the conventional patch test. METHODS: In this multicentre, prospective, randomized, investigator-blinded reliability study, 132 subjects were enrolled. Simultaneous duplicate strip and conventional patch tests were performed with the Finn Chambers® on Scanpor® tape test system and the patch test preparations nickel sulfate 5% pet., potassium dichromate 0.5% pet., and lanolin alcohol 30% pet. Reliability was estimated by the use of Cohen's kappa coefficient. RESULTS: Parallel-test reliability values of the three standard patch test preparations turned out to be acceptable, with slight advantages for the strip patch test. The differences in reliability were 9% (95%CI: -8% to 26%) for nickel sulfate and 23% (95%CI: -16% to 63%) for potassium dichromate, both favouring the strip patch test. CONCLUSIONS: The standardized strip patch test method for the detection of allergic contact sensitization in patients with suspected allergic contact dermatitis is reliable. Its application in routine clinical practice can be recommended, especially if the conventional patch test result is presumably false negative.

Experimental patch testing with chromium-coated materials.

BACKGROUND: Chromium coatings on metal alloys can be decorative, and prevent corrosion and metal ion release. We recently showed that handling of a chromium-containing disc resulted in chromium deposition on the skin. OBJECTIVES: To examine patch test reactivity to chromium-coated discs. METHODS: We included 15 patients: 10 chromium-allergic patients, and 5 patients without chromium allergy. All were patch tested with potassium dichromate, cobalt chloride, nickel sulfate, and nine different metallic discs. The chromium-allergic patients were also patch tested with serial dilutions of potassium dichromate. RESULTS: Positive/weaker reactions were observed to disc B (1 of 10), disc C (1 of 10), and disc D, disc E, and disc I (4 of 10 each). As no controls reacted to any of the discs, the weak reactions indicate allergic reactions. Positive patch test reactions to 1770 ppm chromium(VI) in the serial dilutions of potassium dichromate were observed in 7 of 10 patients. When the case group was narrowed down to include only the patients with a current positive patch test reaction to potassium dichromate, elicitation of dermatitis by both chromium(III) and chromium(VI) discs was observed in 4 of 7 of patients. CONCLUSIONS: Many of the patients reacted to both chromium(III) and chromium(VI) surfaces. Our results indicate that both chromium(VI) and chromium(III) pose a risk to chromium-allergic patients.

Time trends of contact allergy to the European baseline series in Lithuania.

BACKGROUND: Monitoring trends of positive patch test reactions is useful for epidemiological surveillance and contact allergy prevention, and has not previously been reported in Lithuania. OBJECTIVES: To examine and compare changes in the prevalence of contact allergy to European baseline series allergens in adults with suspected contact dermatitis during a 9-year period. METHODS: In this retrospective study, patch test results of 297 consecutive patients, tested with the European baseline series in 2014-2015, were analysed and compared with the data published earlier in Lithuania. RESULTS: The most common allergens were nickel sulfate (30.6%), methylisothiazolinone (MI) (13.5%), methylchloroisothiazolinone (MCI)/MI (7.4%), potassium dichromate (6.1%), cobalt chloride (6.1%), Myroxylon pereirae resin (5.4%), p-phenylenediamine (5.4%), fragrance mix I (4.7%), formaldehyde (4.4%), and methyldibromo glutaronitrile (3.7%). Increases in the prevalence of sensitization to MCI/MI (2.3% in 2006-2008 and 7.4% in 2014-2015; p < 0.0001) and nickel sulfate (16.4% in 2006-2008 and 30.6% in 2014-2015; p < 0.0001) and decreases in the prevalence of sensitization to paraben mix (3.2% in 2006-2008 and 0.3% in 2014-2015; p = 0.006) were observed. Prevalences for the other allergens remained stable or showed a decreasing trend (Myroxylon pereirae resin; p = 0.06). CONCLUSION: This study provides current information on the prevalence of contact allergy in Lithuania. Changing trends in sensitivity to some allergens probably reflect changes in exposure.

Chromate and amine contact allergies in workers manufacturing precast concrete elements.

BACKGROUND: Five workers from a plant manufacturing concrete wall panels and beams were referred to our department because of suspected occupational dermatitis. When patch tested, 3 workers reacted to potassium dichromate. Four workers reacted to ethylenediamine dihydrochloride, without any obvious exposure. Owing to the high proportion of workers with recent-onset skin disease, an investigation of all workers at the plant was initiated. OBJECTIVES: To investigate the prevalence of occupational dermatitis and contact allergy in the workers at the plant. METHODS: All 24 workers at the plant underwent a clinical investigation and were patch tested. RESULTS: Four cases of allergic occupational contact dermatitis and 3 cases of irritant occupational contact dermatitis were diagnosed. Contact allergy to potassium dichromate was found in 4 workers. All 4 also reacted to ethylenediamine dihydrochloride and/or amines that were present as additives in the cement. CONCLUSIONS: Chromate contact allergy can still be found in concrete workers, despite the legislation regulating the amount of hexavalent chromium (chromate) in cement. Occupational contact allergy to amines can be found in workers exposed to cement and concrete, so amines should be tested in these workers.

Foot contact dermatitis: nitrofurazone as the main cause in a retrospective, cross-sectional study over a 16-year period from Turkey.

BACKGROUND: The major causative agents in allergic contact dermatitis of the foot may differ from country to country. Sufficient data on foot eczema in patients from Turkey are lacking. OBJECTIVE: To identify the clinically relevant contact allergens in foot eczema and determine the role of patch test series and patients' own materials in the detection of the responsible allergens. METHODS: Among 1753 patients patch tested between 1996 and 2012 in our clinic, 53 with suspected allergic foot eczema were enrolled in this retrospective, cross-sectional study. Forty nine patients were patch tested with the extended European baseline series, 49 with supplemental series including rubber, leather, topical drugs, textile, cosmetic series containing preservatives and emulgators and varnish/plastic/glue series, and 37 with their own substances. RESULTS: Thirty of the 53 patch tested patients showing sensitization to at least one clinically relevant allergen were diagnosed with allergic foot eczema. The main eliciting agent was nitrofurazone (n = 8), followed by leather shoe allergens, ie, potassium dichromate (n = 6), p-tert-butylphenol formaldehyde resin and formaldehyde, in the second range. Rubber shoe allergens were less frequently observed (n = 3). In more than 1/3 of the patients, the causative agent could only be identified by testing the patient's own substances and/or supplemental series. CONCLUSION: Nitrofurazone was the leading causative agent followed by leather shoe allergens. Pediatric patients were frequently sensitized with shoe allergens. Patch testing with patient's own substances had a critical value in the detection of the causative agent in a significant number of patients.