Performed Patch Tests Research Articles

Fragrance Contact Allergy - A Review Focusing on Patch Testing.

Fragrance materials are widely used in various types of products in daily life and many of them can be contact sensitizers. Contact allergy to fragrances has been reported to be common worldwide. Unlike other groups of contact allergens such as metals and preservatives, fragrance materials in consumer products can be present as single fragrance chemicals or in the form of mixtures known as natural complex substances. Due to the complexity of the fragrance materials and the high number of fragrance substances known to cause contact sensitization, selecting suitable materials for patch testing is challenging. Emerging fragrance markers have been additionally introduced in different baseline series for screening to enhance the rate of fragrance contact allergy detection. Moreover, there have been continual updates on basic knowledge, clinical perspectives, sources of exposure, and regulations on the use of fragrance materials. Avoiding pitfalls while performing patch testing with fragrance test materials is also crucial and should not be overlooked. Therefore, this review aims to update knowledge to provide a high-quality holistic approach to fragrance contact allergy diagnosis and management.

Patch Testing in Patients With Severe Atopic Dermatitis Treated With Dupilumab: A Multicentric Approach in Spain.

Background: Persistent localized dermatitis (PLD) or eczema flare-ups (EF) may occur in atopic dermatitis (AD) patients treated with dupilumab. They may reflect concomitant allergic contact dermatitis (ACD) exposed by the inhibition of the Th2 pathway by dupilumab in some cases. Objective: To evaluate the prevalence and etiology of these events and the impact of dupilumab on patch test outcome. Methods: We performed patch tests on 54 AD patients treated with dupilumab and evaluated the prevalence and final diagnosis of EF and PLD as well as the patch test results. Results: The patch test results were positive in 20/54 (37.0%). 21/54 patients (38.9%) had PLD and 12/54 (22.2%) had EF. Ten of 54 (18.5%) had both conditions and 11/54 (20.4%) had neither PLD nor EF. 64.5% of PLD involved the face. 83.9% patients with PLD and 90.9% patients with EF were diagnosed with inadequately controlled AD. 9.7% patients with PLD and 4.5% patients with EF were finally diagnosed with ACD. Nine of 21 (42.9%) patients patch tested twice were positive either before and/or during dupilumab. Patch tests results changed over time in all of them. Conclusions: Patch testing assisted us to exclude ACD as the cause of PLD/EF in AD patients treated with dupilumab. Most PLD and EF were, however, diagnosed as poorly controlled AD. Dupilumab appeared to impact the patch test outcomes.

Allergic contact dermatitis to chlorhexidine-containing antiseptics in infants and children: the origin of sensitization and the role of the excipients in this sensitization (a series of ten cases).

The recent COVID-19 pandemic provoked an outstanding increase of infection-control measures, with chlorhexidine becoming an extensively used antiseptic. Allergic contact dermatitis to chlorhexidine is considered as a rare event in children, is often difficult to identify, and its diagnosis is often misdiagnosed as other skin diseases. We aimed to explore the sensitization to chlorhexidine-containing antiseptics in infants and children to determine the origin of their sensitization and the role of the excipients in their dermatosis. We performed patch tests with chlorhexidine digluconate 0.5%, benzalkonium chloride 0.1%, benzyl alcohol 10%, 5% and 1% in ten children (1-16.5-year-old) with severe contact reactions to chlorhexidine-based antiseptics (Biseptine®) and cosmetics. We also performed patch tests with sodium benzoate 5% in four of the children. Results were measured according to criteria recommended by the International Contact Dermatitis Research Group. Patch test reactions revealed that most children were sensitized to at least two components of chlorhexidine-containing antiseptics (chlorhexidine, benzyl alcohol and/or benzalkonium chloride). To explore the origin of the sensitization, we searched for umbilical cord care with chlorhexidine- containing antiseptics and the use of cosmetics and drugs containing chlorhexidine and excipients of chlorhexidine-containing antiseptics. Most parents reported prior disinfection of umbilical cord with chlorhexidine-containing antiseptics, but this was not always the case. Allergic contact dermatitis to chlorhexidine, benzyl alcohol and benzalkonium chloride should be considered in infants and children with severe eczema and concomitant allergies. The regular use of cosmetics and drugs containing chlorhexidine, benzyl alcohol, benzalkonium chloride or sodium benzoate should be cautioned or avoided in children with severe eczema or pre-existing allergies. Early suspicion and allergology exploration of allergic contact dermatitis to chlorhexidine-containing antiseptics and their excipients is of paramount importance to help prevent severe allergic reactions to topical antiseptics and numerous cosmetics.

The prevalence and relevance of patch testing with textile dyes.

Textile dye mix (TDM) is included in the European baseline series (EBS), but it is unknown if TDM identifies all patients with a textile dye allergy. To assess the added value of performing patch testing with individual textile dyes in addition to TDM. Two hundred and nine patients suspected to have a contact allergy to textile dyes were patch tested between January 2015 and December 2021 with the EBS, as well as an individual textile dye test series containing textile dyes part of TDM (TDM-dyes) and outside the scope of TDM (non-TDM dyes). Fifty-four patients (25.8%) tested positive for TDM or an individual textile dye. Disperse Orange 3 (9.6%) followed by Disperse Blue 106 (4.8%) were the most common individual textile dyes causing a positive patch test reaction. Of the 54 dye positive patients, 28 (51.9%) had a clinically relevant reaction. No clinically relevant reactions were seen in patients that solely tested positive for non-TDM dyes. It is beneficial to test individual textile dyes in addition to TDM in patients suspected of having a textile dye allergy. Otherwise, 46.3% of the dye positive patients and 35.7% of the patients with a clinically relevant reaction would have been missed.

POSTSURGICAL ACUTE GENERALIZED EXANTHEMATOUS PUSTULOSIS: TIMING IS EVERYTHING

<h3>Introduction</h3> Acute generalized exanthematous pustulosis (AGEP) is a severe cutaneous adverse reaction commonly caused by antibiotics. <h3>Case Description</h3> A 62-year-old male was evaluated for a painful and burning pustular eruption three days after a hip arthroplasty. Medication timeline was notable for intraoperative (3 days prior) receipt of cefazolin, dexamethasone, hydromorphone, ropivacaine, and tranexamic acid. Two days prior, he received oxycodone, ondansetron, omeprazole, sennosides, and dexamethasone. One day prior to presentation he received meloxicam and aspirin. Physical examination revealed confluent erythema studded with pinhead-sized sterile pustules on the bilateral thighs, under arms (Figure 1A), and trunk. Complete blood count with differential showed mild neutrophilia (7.59; ref 1.56-6.45 × 10⁻⁹/L) and a complete metabolic panel was within normal limits. Histopathology of a punch biopsy from the right thigh revealed subcorneal pustules with epidermal spongiosis, mild papillary dermal edema and a mixed perivascular infiltrate (Figure 1B) consistent with AGEP. He was instructed to avoid all beta-lactams, non-steroidal antiinflammatory agents (NSAIDs), and steroids. The eruption completely resolved within 10 days of avoidance measures and antihistamines. There were plans to perform patch testing to cefazolin, prednisone, and dexamethasone. Unfortunately, the patient was lost to follow-up. <h3>Discussion</h3> AGEP is diagnosed clinically and confirmed by a skin biopsy. Patch testing may be utilized to evaluate for the culprit agent; but when this is not available, the timeline between medication exposure and index reaction may aid in causal agent identification. The median time from exposure to onset of AGEP is 1 day for antibiotics versus 11 days for all other medications.

O100 The effect of nickel hypersensitivity on outcome of total knee arthroplasty and value of skin patch testing: a systematic review

Abstract Introduction Aims of the systematic review were to assess the sensitising potential of TKA, explore the relationship between Nickel hypersensitivity and clinical outcomes, and evaluate the utility of skin patch testing pre- and/or post-operatively. Methods A literature search was performed through EMBASE, Medline and PubMed databases. Articles were screened independently by two authors. Levels of Evidence were assessed using OCEBM criteria, and quality assessed using MINORS and Cochrane risk-of-bias tools. Results Twenty studies met the eligibility criteria, reporting on 1354 knee arthroplasties. Prevalence of Nickel hypersensitivity ranged from 0% to 87.5%. Only one study which compared prevalence of hypersensitivity in the same patient group before and after surgery noted newly positive patch test reactions in 4.1%. Three studies reported lower prevalence of hypersensitivity in post-operative patients compared to pre-operative patients. Seven studies suggested hypersensitivity might cause complications; six studies did not support any relationship. Seven studies recommended pre-operative patch testing in patients with history of metal allergy; nine studies concluded testing may be valuable post-operatively. Conclusion Patients undergoing TKA do not seem to be at increased risk of developing Nickel hypersensitivity, however there is conflicting evidence that patients with established hypersensitivity are more likely to experience adverse clinical outcomes. Patch testing remains the gold standard diagnostic method; evidence suggests performing this test pre-operatively in patients with history of metal allergy to aid selection of the most appropriate prosthesis, and postoperatively once common causes of implant failure have been excluded, since implant removal or revision with hypoallergenic implants may alleviate symptoms. Take-home message Patients undergoing total knee arthroplasty do not seem to be at an increased risk of developing nickel hypersensitivity, and there is mixed evidence that patients with hypersensitivity are more likely to experience adverse clinical outcomes. Evidence suggests performing patch testing preoperatively in patients with a history of metal allergy to aid selection of the most appropriate prosthesis, and post-operatively only once more common causes of implant failure have been excluded.

What We Have Learned-Milestones in Pediatric Contact Dermatitis.

Purpose of ReviewThis review highlights recent developments in the field of pediatric allergic contact dermatitis (ACD) and patch testing. We will review updates on the pathophysiology of contact dermatitis, discuss new contact allergens, explore the impact of dupilumab on patch testing, and provide pearls for the diagnosis and management of ACD in children.Recent FindingsACD is not a single immunologic phenomenon but rather has contributions from multiple inflammatory pathways. Emerging contact allergens include ingredients found in “slime” toys, glucose monitors and insulin pumps, and electronic equipment. Data thus far suggests that patch testing results are generally reliable in the face of concurrent dupilumab use.SummaryACD is likely underrecognized and underdiagnosed in pediatric patients, including infants and young children. Providers should keep patient-specific factors and emerging trends in mind when addressing suspected ACD, consider contact dermatitis when they encounter challenging cases of atypical, refractory, or chronic dermatitis, and feel comfortable performing patch testing in children.

Allergic contact dermatitis to phenoxyethanol: A rare, but possible cause of hand dermatitis.

Phenoxyethanol (PE; Syn. 2-Phenyoxethanol; CAS no. 122-99-6) is one of the most commonly used preservatives in cosmetics and is also found in industrial products, including metalworking fluids. It is considered to have a low sensitization potential.1-3 A 59-year-old male toolmaker presented with therapy-resistant, 1-year lasting hand dermatitis suspected to be of occupational origin. Despite being on work leave and treatment with alitretinoin for the past 5 months, severe dermatitis of hands and lower arms was observed (Figure 1). We performed patch tests and readings according to the guidelines of the German Contact Dermatitis Research Group (DKG)4 using the DKG baseline series; the DKG series for topical preparations, preservatives, rubber, disinfectants, acrylates, industrial biocides, and metalworking fluids; and the patient's own metalworking fluid. Patch tests were removed at day (D) 2 with the exception of the metalworking fluid, which was removed already at D1 and reactions were evaluated at D2, D3, D4, and D7. Solely, a 2+ reaction to PE 1% pet. (SmartPractice, Greven, Germany) from D2 to D7 was noted (Figure 2A). PE was not found in any of the available safety datasheets of the patient's workplace products, including the metalworking fluid. However, according to the product labels, it was an ingredient of the patient's skin care products “Eucerin UreaRepair PLUS 5% Hand Creme” and “Nivea 3IN1 Repair Hand Creme” (both from Beiersdorf AG, Hamburg, Germany), which he had regularly applied on his hands and lower arms after the onset of dermatitis. Repeated open application test (ROAT) with “Eucerin UreaRepair PLUS 5% Hand Creme,” two times daily for 6 days on the inner sides of the patient's upper arm resulted in a positive reaction (Figure 2B). Dermatitis of hands and lower arms improved significantly after avoidance of these skin care products, indicating clinical relevance of the sensitization to PE as the contributing factor to the initially occupational irritant contact dermatitis. Despite its widespread use as preservative in cosmetic and pharmaceutical products as well as for other applications, only very few cases of allergic contact dermatitis and contact urticaria to PE have been reported.2, 5-7 Accordingly, a retrospective study of the Information Network of Departments of Dermatology (IVDK) revealed a very low sensitization rate of 0.24% among 6932 individuals patch tested in Germany, Austria, and Switzerland between 1996 and 2009.1 Similarly, in 681 cutting metalworkers patch tested with the DKG metalworking fluids series in IVDK centres from 2010 to 2018, sensitization to PE was rarely observed (0.3%).8 Although rare, allergic contact dermatitis to PE should be considered and if undiscovered may lead to longstanding disease and inefficient treatments. The present case illustrates the importance of performing early patch tests to avoid delays in diagnosis and prevention measures. Diagnostic workup of patients with suspected occupational hand dermatitis should include patch testing and in doubtful cases also ROAT with patient's own skin care products. The authors declare no conflicts of interest. Michaela Kolodziej: Conceptualization (equal); investigation (equal); writing – original draft (equal); writing – review and editing (equal). Alexander Kiewert: Investigation (supporting); writing – review and editing (equal). Christoph Skudlik: Investigation (supporting); writing – review and editing (equal). Richard Brans: Conceptualization (equal); investigation (equal); supervision (lead); writing – original draft (equal); writing – review and editing (equal).

Gradient boosting approaches can outperform logistic regression for risk prediction in cutaneous allergy.

Contact allergy is a major clinical and public health challenge. It is important to identify individuals who are at risk and perform patch testing to identify relevant allergens. Predicting clinical risk on the basis of input parameters is common in clinical medicine and traditionally has been achieved with linear models. We hypothesized that the risk of a clinically relevant positive patch test could be predicted according to clinical and demographic parameters. We compared the predictive accuracy of logistic regression with more sophisticated machine learning approaches such as gradient boosting, in the prediction of patch testing results. We found that both logistic regression and more sophisticated machine learning approaches were able to predict the risk of positive patch tests. For certain predictions, including the overall risk of a clinically relevant positive patch test, gradient boosting approaches can outperform logistic regression. These findings suggest that complex nonlinear interactions between input variables are relevant in risk prediction. While a risk prediction model cannot replace the judgment of an experienced clinician, quantifying the risk of a clinically relevant positive patch test result has the potential to assist in decision making and to inform discussions with patients.

Contact dermatitis: etiology, pathophysiology, clinical features and diagnostics

Ernesta Pranskaitytė1, Laura Malinauskienė1 1 Clinic of Chest Diseases, Immunology and Allergology, Faculty of Medicine, Vilnius University, Vilnius, Lithuania Abstract Background. Contact dermatitis (CD) is a common skin disease with an increasing prevalence. It is a non-infectious skin inflammation that occurs after contact with an allergen or irritant. Based on pathophysiological mechanism, CD is divided into allergic CD (ACD) and irritant CD (ICD). ACD and ICD can co-exist due to the use of both the allergens and irritants, which leads to impaired skin barrier and promotes the development of CD. CD usually manifests as erythema, oedema, papules, pustules, and itchy skin. CD is diagnosed from a medical history, symptoms, and by performing patch testing. Dermatitis can be prevented by identifying and avoiding CD causing substances. Aim: to review an aetiology, risk factors, pathophysiology, diagnostics, clinical features of CD, ACD and ICD comorbidity. Methods: the review of literature was conducted using „PubMed“ and „UpToDate“ databases, using the keywords “Contact dermatitis”, “Allergic contact dermatitis”, “Contact allergy”, “Irritant contact dermatitis”, “Irritants”, “Allergens”. Keywords: contact dermatitis, allergic contact dermatitis, irritant contact dermatitis, allergens, irritants.

Study of Common Allergens in Patients with Allergic Contact Dermatitis: A Hospital Based Study

Allergic contact dermatitis (ACD) is one of the most common diseases presenting to the Dermatology department. The one and only method of preventing as well as treating this disease is avoidance of the allergen causing it. The identification of the allergen causing the ACD is possible by performing patch testing. The purpose of this study was to identify common allergens among patients with ACD using Indian standard series (ISS) of patch test. Clinically suspected cases of ACD were included in the hospital based cross-sectional study from January to December 2017. These cases underwent patch testing with the ISS. The study assessed the following variables: sex, age, occupation, site and positive patch test results. There were a total of 58 patients among which, 36.2% were males and 63.8% were females with a mean age of 32.36±12.51 years. Positive patch test reactions were seen in 63.0% of patients. The most common allergens were nickel sulphate (51.4%), fragrance mix (37.8%), potassium dichromate (8.1%), colophony (8.1%) and black rubber mix (8.1%). Among male, most common allergens were fragrance mix (57.1%), nickel sulphate (28.6%) and potassium dichromate (21.4%) while in female, most common allergens were nickel sulphate (65.2%) and fragrance mix (26.1%). In our study, majority of the allergens were positive. Hence, the ISS used in the study might be suitable in the context of Nepalese population. However, further similar studies on large number of patients with multiple allergens are required to determine the exact number of contact allergens prevalent in our population.

Patch Test Result in Patient with Allergic Contact Dermatitis to Toothpaste: A Case Report

Background: Allergic contact dermatitis (ACD) is a common diagnosis resulting from exposure to a chemical or chemicals in a patient's personal care products, home, or work environment. It is a delayed type of hypersensitivity reaction caused by contact with allergens in the environment. Patch testing is a gold standard to establish the diagnosis. After the causative allergens have been identified, patient education is needed to the proper treatment and management of the patient. Case: Herewith, we report A 23-year-old woman with suspected ACD due to lipstick and was planned to perform patch test. She complained about dry lips that appear after she used new lipstic for about 3 months and there was not history of applying another agent. After recovery, the patch test was performed with allergens that might contact with her lips and the result was positive one in toothpaste allergen while negative in lipstick allergen. Conclusion: The allergen which is suspected to the patient from history-taking might be different with the result of patch test, so that performing patch testing is needed to investigate the cause of ACD.

ASSESSMENT OF ALLERGIES TO FOOD AND ADDITIVES IN PATIENTS WITH ANGIOEDEMA, BURNING MOUTH SYNDROME, CHEILITIS, GINGIVOSTOMATITIS, ORAL LICHENOID REACTIONS, AND PERIORAL DERMATITIS.

SUMMARYOral cavity and perioral area are constantly exposed to a variety of antigens, including food and additives, which have a potential role in the development of different oral mucosal and perioral cutaneous diseases since they can cause hypersensitivity reactions. Oral and perioral diseases mainly include angioedema, burning mouth syndrome, cheilitis, gingivostomatitis, oral lichenoid reactions, and perioral dermatitis. Previous studies were focused on delayed-type oral allergies by performing patch testing but did not include tests for immediate-type allergic reactions. Therefore, the objective of this study was to determine common nutritive and additive allergens in the prevalent oral and perioral diseases by using skin prick tests. Our study evaluated 230 participants, i.e. 180 patients with oral/perioral diseases (angioedema, burning mouth syndrome, cheilitis, gingivostomatitis, oral lichenoid reactions, and perioral dermatitis), and 50 healthy control subjects. The results of skin prick tests showed that immediate-type allergic reactions to food and additives were mostly seen in patients with burning mouth syndrome (40%) and cheilitis (33.3%), whereas allergies were least frequently observed in perioral dermatitis (10%) and gingivostomatitis (20%). Fruits, mushrooms, and vegetables were the most frequent causes of nutritive allergies in oral and perioral diseases. The most commonly identified additive allergens were glutaraldehyde, citric acid, and sodium glutamate. Study results suggest the possible association with nutritive and additive allergies be considered in cases of persistent oral mucosal or perioral skin disease accompanied by respective medical history.

Contact dermatitis associated with the Bispectral index\u2122 sensor: a case report

BackgroundContact dermatitis caused by electroencephalography electrodes is rare and insufficiently studied. We described a case of contact dermatitis caused by Bispectral Index (BIS) monitor electrodes.Case presentationA 38-year-old woman underwent tooth extraction under general anesthesia with BIS monitoring. She noticed erythema on her forehead 3 days after surgery, which peaked on the fifth postoperative day. Slight pigmentation was observed at 42 days after surgery. We performed patch testing and confirmed positive reactions to the sensor and some allergens.ConclusionsMany reports have attributed contact dermatitis to an allergen present in electrocardiogram electrodes. It is important to recognize that complications similar to those caused by electrocardiogram electrodes can occur with this sensor.

Changes in Chinese patch testing practices over 13 years: Updated cross-sectional survey and possible international implications.

Patch testing, the standard method for diagnosing allergic contact dermatitis, has been utilized for over 30 years in China. A 2006 survey found that patch testing was widespread among Chinese dermatologists, but the practice and perceptions were unsatisfactory. To evaluate the current situation of patch testing practice and perception, we resurveyed Chinese dermatologists. A cross-sectional survey of Chinese dermatologists was conducted by electronic questionnaires at the 15th National Congress of Dermatology in November 2019. There were 2199 valid questionnaires collected. About 75% of dermatologists performed patch testing; the majority (59.2%) utilized the baseline (standard) allergen series made in China; others used TRUE Test or the Chemotechnique Diagnostics series, a greater share compared with 2006. Most (92.8%) performed only one single reading, more than 2006. About two-thirds offered patient education after patch testing, but only 27% were executed by trained dermatologists. Dermatologists from regional hospitals more likely performed patch testing and had better perception of patch testing. The majority (88.1%) had received patch testing training, which however did not significantly improve dermatologists' perception. There was an insignificant improvement in practice and perception of dermatologists compared with 2006. Further education and studies should be conducted. Similar surveys in other countries would be of interest.

Chronic Hand Eczema Guidelines From an Expert Panel of the International Eczema Council.

BackgroundAssessment of chronic hand eczema (CHE) is complex and warrants standardization.ObjectiveWe sought to guide clinicians on the assessment of CHE.MethodsAn electronic questionnaire regarding the diagnosis and assessment of CHE was completed by councilors (n=45) of the International Eczema Council, an international group of clinicians and researchers with expertise in CHE. The survey consisted of 52 statements for consensus.ResultsOverall, nine statements (17.3%) had strong, twenty-three (44.2%) moderate, 12 (23.1%) low, and 8 (15.4%) very low levels of agreement. Five statements had considerable disagreement, including the value of conducting a skin biopsy (62.2% disagreement), investigating for possible type 1 reactions (60.0%), conducting a fungal culture (44.4%), finding no history of relevant allergens and/or irritants (31.1%) in most or all cases, and performing patch testing irrespective of lesion location and morphology (28.9%). Agreement was generally highest among respondents from Europe (28.6–77.8% agreement), followed by Asia (7.1%–35.7% agreement), North America (0%–35.5% agreement), and other (0%–13.3% agreement).ConclusionsThere were substantial differences of agreement, suggesting there are many knowledge and/or practice gaps with respect to CHE. Future research is needed to inform evidence-based and/or consensus guidelines for CHE.

Patch testing in New Zealand: Barriers to evidence-based care.

Allergic contact dermatitis is a disabling condition, significantly impacting on quality of life, which can only be alleviated by identification and avoidance of a relevant allergen. Patch testing remains the gold standard diagnostic test for allergic contact dermatitis. The consistency with which patch testing is used varies throughout the world. The purpose of this study was to look at the adequacy of current patch testing practice in New Zealand. We undertook literature review of current guidance regarding patch testing and created a web-based survey to evaluate use of patch testing in New Zealand. This was sent to all 75 vocationally registered New Zealand dermatologists. Of respondents, 46% do not perform patch testing. The most commonly cited barriers were lack of nursing support, poor remuneration, time pressure and lack of facilities. 23% noted that public patch testing services are not available in their region. The majority do not record patch test results in a database. Access to and utilisation of patch testing in New Zealand is suboptimal. Increasing services in the public sector requires investment by health boards, as there remains a dermatology workforce shortage in New Zealand. In private practice, patients often find it unsatisfactory to pay for negative tests, and adequate remuneration of patch testing by private insurers is necessary. Surveillance of patch test results at a national level is lacking, and the development of a centralised database to identify common allergens affecting our population is recommended.

Diagnosis of contact allergy in practice using current guidelines

In the case of acontact allergy, there is only allergen avoidance instead of causal therapy. If the allergen is not identified, dermatitis persists, which is amajor burden for patients. Patch testing is the diagnostic standard for detecting contact sensitization. Based on asystematic literature search, the German patch test guideline was updated and methodologically upgraded. The most important practical aspects of patch testing with contact allergens and drugs are presented. Current consensus guidelines for performing patch tests as well as the results of a supplementary selective literature search are summarized. According to the patch test guideline (AWMF registry no. 013-018, 2019), the baseline series, special series and, if necessary, test preparations prepared from the patient's own contact substances should be tested routinely. Anew evidence-based recommendation is alate reading after 7-10days, as otherwise numerous patch test reactions will be missed. Antihistamines may weaken the cellular reactions of the patch test and should be discontinued with alatency of 5half-lives. Finally, if afalse-negative patch test result is suspected, it is recommended to perform astrip patch test according to the validated protocol. All patients with asuspected contact allergy should receive aguideline-based patch test at an early stage. Targeted patch testing identifies clinically relevant allergens and provides suggestions for further systematic investigations.

An observational study to determine the sensitizing potential of orthopedic implants.

Patients who receive orthopedic implants have been shown to develop sensitivity to its components and there are concerns that this sensitivity might lead to contact dermatitis or implant-related problems like loosening and/or failure. The objective of the study was to determine the sensitizing potential of orthopedic implants. Fifty-four patients undergoing knee, hip, or shoulder replacement surgeries between July 2014 and July 2015 were recruited. Patch tests were performed before the implant surgery with 10 allergens likely to be implicated in metal hypersensitivity. Postimplant patch test was performed 6 months after surgery. A majority of the patch tests were applied on the arms. Four positive reactions were recorded in the preimplant patch tests - three positive reactions to nickel and one to chromium. Thirty patients made themselves available for the follow-up patch test. The incidence of new contact sensitivity to components of implants was 13.8% (4/29) at 6 months. One patient who had undergone knee replacement developed eczematous lesions around the knee joint after surgery. This patient tested negative to patch test at both the times. Short follow-up duration and performing patch tests on the arms, a site known to elicit less positive patch test response compared to the back in sensitized individuals, are limitations of the study. There is an increase in the sensitivity to implanted components after 6 months of joint replacement surgery. The incidence of new sensitivity to a component of the implant was 13.8% (4/29). In this context, nickel is a good sensitizer and could sensitize 50% of patients who received a nickel-containing implant.

Nummular Contact Eczema: Presentation of a Pediatric Case

The etiopathogenesis of the nummular eczema is not fully known. Various causative factors have been proposed, and among these only a few studies investigate the relevance of contact allergy. Here, we present a case of nummular contact eczema in an 8-year-old allergic to perfumes. Since atopic dermatitis may also present with different clinical phenotypes, among which nummular eczema is quite frequent, the possible significant differences between non-atopic and atopic nummular diseases are considered. Based on the high incidence of contact sensitization in all cases of nummular eczema, it is recommended to perform patch tests for diagnostic-preventive purposes.