Skin Patch Testing Research Articles

Is there a role of toothpastes in the development of recurrent aphthous stomatitis? A prospective controlled clinical trial with skin patch testing

The oral mucosa is exposed to a large number of antigenic agents contained in toothpastes. These agents are reported to stimulate recurrent aphthous stomatitis (RAS) pathogenesis, and toothpastes that do not contain probable allergenic substances reduced the number and frequency of aphthous ulcers. We aimed to determine whether the skin patch test (SPT) can be used to determine if toothpaste allergens play a role in the etiology of RAS. Sixty-three patients with RAS and 47 healthy volunteers were skin patch tested with sodium lauryl sulfate, cocamidopropyl betaine, propylene glycol, aluminum chloride hexahydrate, menthol, triclosan, and titanium dioxide, which are present in most of the toothpastes. Fisher's exact test and the Yates chi-square test were used to compare categorical variables and patch test results between 2 groups. The SPT was positive in 8 (22.2%) patients with RAS and 11 (23.4%) control subjects, and the difference between the groups was not statistically significant (P < .05). Sodium lauryl sulfate, titanium dioxide, and menthol were the most common positive allergens in both groups. Allergens in toothpastes did not appear to stimulate the formation of RAS. However, in order to determine a clearer relationship, a study in a larger patient series employing intraoral patch testing with more toothpaste ingredients is suggested.

Nickel Allergy of the Skin and Beyond.

Hypersensitization to nickel is one of the most common contact allergies in the modern world and it is considered to be a major cause of contact dermatitis, especially for hand eczema. The aim of this paper is to describe many faces of the nickel allergy and to find out different diagnostic, potential strategies for treatment and prevention in hypersensitized patients. A personal clinical experience with practical clinical cases of contact dermatitis to nickel has also been presented. Electronic databases on this topic was carried out using PubMed-Medline. The literature review identified many articles reporting for nickel contact allergy and pointing the metal as number one allergen in the frequency of positive skin patch test reactions in a large population worldwide. Herein, a summary of the current understanding and evidence on nickel allergy with practical approach and proposed recommendations to the dermatologist, general practitioner, and the allergist were prepared. The prevalence of nickel allergy represents an important socio-economical and health issue. Metal is one of the most common sensitizing agents worldwide. The morbidity due to this metal represents the allergic contact dermatitis and it is constantly growing in many countries. There are also cases of systemic allergic contact dermatitis, where they could be easily misdiagnosed as adverse drug reactions, which lead to delay of the correct diagnosis and inappropriate treatment.

The suitability of reconstructed human epidermis models for medical device irritation assessment: A comparison of In Vitro and In Vivo testing results

The ISO 10993 standards on biocompatibility assessment of medical devices discourage the use of animal tests when reliable and validated in vitro methods are available. A round robin validation study of in vitro reconstructed human epidermis (RhE) assays was performed as potential replacements for rabbit skin irritation testing. The RhE assays were able to accurately identify strong irritants in dilute medical device extracts. However, there was some uncertainty about whether RhE tissues accurately predicted the results of the rabbit skin patch or intracutaneous irritation test. To address that question, this paper presents in vivo data from the round robin and subsequent follow-up studies. The follow-up studies included simultaneous in vitro RhE model and in vivo testing of round robin polymer samples and the results of dual in vitro/in vivo testing of currently marketed medical device components/materials. Our results show for the first time that for both pure chemicals and medical device extracts the intracutaneous rabbit test is more sensitive to detect irritant activity than the rabbit skin patch test. The studies showed that the RhE models produced results that were essentially equivalent to those from the intracutaneous rabbit skin irritation test. Therefore, it is concluded that RhE in vitro models are acceptable replacements for the in vivo rabbit intracutaneous irritation test for evaluating the irritant potential of medical devices.

Prognostic tools for hypertrophic scar formation based on fundamental differences in systemic immunity.

Unpredictable hypertrophic scarring (HS) occurs after approximately 35% of all surgical procedures and causes significant physical and psychological complaints. Parallel to the need to understanding the mechanisms underlying HS formation, a prognostic tool is needed. The objective was to determine whether (systemic) immunological differences exist between patients who develop HS and those who develop normotrophic scars (NS) and to assess whether those differences can be used to identify patients prone to developing HS. A prospective cohort study with NS and HS groups in which (a) cytokine release by peripheral blood mononuclear cells (PBMC) and (b) the irritation threshold (IT) after an irritant (sodium lauryl sulphate) patch test was evaluated. Univariate regression analysis of PBMC cytokine secretion showed that low MCP‐1, IL‐8, IL‐18 and IL‐23 levels have a strong correlation with HS (P < .010‐0.004; AUC = 0.790‐0.883). Notably, combinations of two or three cytokines (TNF‐a, MCP‐1 and IL‐23; AUC: 0.942, Nagelkerke R2: 0.727) showed an improved AUC indicating a better correlation with HS than single cytokine analysis. These combination models produce good prognostic results over a broad probability range (sensitivity: 93.8%, specificity 86.7%, accuracy 90,25% between probability 0.3 and 0.7). Furthermore, the HS group had a lower IT than the NS group and an accuracy of 68%. In conclusion, very fundamental immunological differences exist between individuals who develop HS and those who do not, whereas the cytokine assay forms the basis of a predictive prognostic test for HS formation, the less invasive, easily performed irritant skin patch test is more accessible for daily practice.

Titanium Niobium Nitride Mobile-Bearing Unicompartmental Knee Arthroplasty Results in Good to Excellent Clinical and Radiographic Outcomes in Metal Allergy Patients With Medial Knee Osteoarthritis

BackgroundThe main purpose of the present study was to analyze the clinical and radiological outcomes of patients with positive skin patch tests who underwent medial mobile-bearing titanium niobium nitride unicompartmental knee arthroplasty (UKA) during a mid-term follow-up. MethodsThirty-seven patients with positive skin patch tests were included in this prospective study. The clinical evaluation consisted of Oxford Knee Score and Knee Society Score (KSS) reports. Each patient was clinically evaluated the day before surgery (T0) as well as at T1 (11.9 ± 1.3 months) and during the final follow-up T2 (67.2 ± 19.1 months). The positioning of the UKA was evaluated during the final follow-up using standardized radiographs (T2: 67.2 ± 19.1 months). ResultsOxford and KSS ranged from a respective mean preoperative value of 23.0 ± 2.7 and 51.5 ± 5.0 to 42.1 ± 1.7 and 87.6 ± 2.2, respectively, at T1 (P < .001) and to the final values of 45.0 ± 1.9 and 91.9 ± 3.4, respectively, at T2 (P < .001 both vs T1 and T2). At T2, the mean femoral angle was 7.0° ± 4.5°, mean tibial angle was 3.0° ± 2.1°, and mean tibial slope was 5.1° ± 3.2°. A significant difference was found between KSS and Oxford with ANOVA for repeated measures over time (P < .001). The Oxford and KSS scores showed significant improvements during each follow-up. No complications were found, and not a single patient required a revision surgery during the follow-up period. ConclusionThe hypoallergenic titanium niobium nitride mobile-bearing UKA showed comparable results to standard CoCr UKA regardless of the gender, age, BMI, and implant size of metal allergy patients with medial knee osteoarthritis. Careful patient selection processes and accurate medical histories played key roles in the choice of hypersensitivity-friendly implants.

Delayed Intracranial Parenchymal Changes After Aneurysmal Coil Embolization Procedures for Unruptured Intracranial Aneurysms.

With the recent advances in endovascular treatment devices, it has become standard in wide-neck or large intracranial aneurysms to perform coil embolization with adjunctive techniques. However, device-related perioperative complications have been reported because of the use of more complex systems. To investigate patients who developed multiple parenchymal lesions after undergoing coil embolization for treating an unruptured intracranial aneurysm. This study investigated 305 consecutive patients who underwent coil embolization of unruptured intracranial aneurysms between 2015 and 2017. Delayed inflammatory changes referred to the delayed observation of multiple cerebral white matter lesions on follow-up magnetic resonance imaging at an area corresponding to the perfused area of the treatment target vessel. The timing and pattern of onset, device used, the combined use of adjunctive techniques, and the clinical course after steroid treatment were retrospectively investigated. The 7 patients (2.3%) who showed delayed inflammatory changes were all women with a mean age of 59 yr. A mean duration from treatment to onset was 28 d. Symptoms were convulsions in 3 patients, hemiplegia in 2 patients, and homonymous hemianopia in 1 patient. All 7 patients were treated with adjunctive technique including stents, double catheter method, and balloon assist. Response to steroid treatment was satisfactory both clinically and on imaging in all 7 patients. Skin patch test was positive for nickel allergy in 2 patients. Clinicians must be fully aware of symptomatic delayed inflammatory changes may occur after endovascular aneurysmal treatment with the use of various devices.

Skin Prick Tests and Patch Tests in Children with Food Allergies.

Abstract Diagnosing food allergies can be challenging for patients and health professionals. Standard diagnostic methods include skin prick testing, food-specific immunoglobulin E (IgE) and oral food challenge. There is no scientifically sufficient evidence for routine use of patch testing for food allergy evaluation in children.

Skin Test for Cutaneous Adverse Drug Reactions

Background: The incidence of drug eruptions is increasing during the last few years due to a large number of new medications. Early detection of the causative agent and the prevention from exposure are crucial managements in terms of drug eruption, mainly to prevent its recurrence. Objective: To understand skin test as a diagnostic modality in drug eruption, which includes skin patch test, skin prick test, and intradermal test. Literature review: Drug eruption is a form of skin eruption triggered by the use of medications, topical or systemic, in the right dose and indication. The manifestation can vary from maculopapular, urticaria, pustular, and bullous eruption; from the most nonsignificant to a life-threatening reaction. A diagnostic procedure is critical to discover the type of drugs that cause the eruption, i.e., skin test, specific IgE measurement, histamine-release test, and provocation test. Skin test is the first choice in the diagnostic process as it is simple, easy, practical and has high sensitivity and specificity. Conclusion: Skin test is one of the many available diagnostic tools. However, both false positive and false negative results might still arise. The experts are currently attempting to come up with more accurate and practical tests to aid the diagnostic of drug eruption, thus preventing its occurrence.

Development and Validation of a Penicillin Allergy Clinical Decision Rule

Penicillin allergy is a significant public health issue for patients, antimicrobial stewardship programs, and health services. Validated clinical decision rules are urgently needed to identify low-risk penicillin allergies that potentially do not require penicillin skin testing by a specialist. To develop and validate a penicillin allergy clinical decision rule that enables point-of-care risk assessment of patient-reported penicillin allergies. In this diagnostic study, a multicenter prospective antibiotic allergy-tested cohort of 622 patients from 2 tertiary care sites in Melbourne, Australia (Austin Health and Peter MacCallum Cancer Centre) was used for derivation and internal validation of a penicillin allergy decision rule. Backward stepwise logistic regression was used to derive the model, including clinical variables predictive of a positive penicillin allergy test result. Internal validation of the final model used bootstrapped samples and the model scoring derived from the coefficients. External validation was performed in retrospective penicillin allergy-tested cohorts consisting of 945 patients from Sydney and Perth, Australia, and Nashville, Tennessee. Patients who reported a penicillin allergy underwent penicillin allergy testing using skin prick, intradermal, or patch testing and/or oral challenge (direct or after skin testing). Data were collected from June 26, 2008, to June 3, 2019, and analyzed from January 9 to 12, 2019. The primary outcome for the model was any positive result of penicillin allergy testing performed during outpatient or inpatient assessment. From an internal derivation and validation cohort of 622 patients (367 female [59.0%]; median age, 60 [interquartile range{IQR}, 48-71] years) and an external validation cohort of 945 patients (662 female [70.1%]; median age, 55 [IQR, 38-68] years), the 4 features associated with a positive penicillin allergy test result on multivariable analysis were summarized in the mnemonic PEN-FAST: penicillin allergy, five or fewer years ago, anaphylaxis/angioedema, severe cutaneous adverse reaction (SCAR), and treatment required for allergy episode. The major criteria included an allergy event occurring 5 or fewer years ago (2 points) and anaphylaxis/angioedema or SCAR (2 points); the minor criterion (1 point), treatment required for an allergy episode. Internal validation showed minimal mean optimism of 0.003 with internally validated area under the curve of 0.805. A cutoff of less than 3 points for PEN-FAST was chosen to classify a low risk of penicillin allergy, for which only 17 of 460 patients (3.7%) had positive results of allergy testing, with a negative predictive value of 96.3% (95% CI, 94.1%-97.8%). External validation resulted in similar findings. In this study, PEN-FAST was found to be a simple rule that accurately identified low-risk penicillin allergies that do not require formal allergy testing. The results suggest that a PEN-FAST score of less than 3, associated with a high negative predictive value, could be used by clinicians and antimicrobial stewardship programs to identify low-risk penicillin allergies at the point of care.

Clinical spectrum of facial hypermelanosis: a descriptive study from a tertiary care centre

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; Facial melanosis (FM) which refers to brown, black or blue pigmentation over the face is a common cosmetic concern in Indian patients. This increased incidence could be due to remarkable diversity of Indian ethinic population. Pigmentary disorders of the face are a great cosmetic and psychological concern for the patients.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; This is an extensive descriptive clinico epidemiological study comprising of 1024 patients, conducted at Sri Venkateshwara Medical College Hospital and Research Centre, Puducherry, for a period of one and a half years. A detailed clinical history and examination was done, and all the clinical photographs and data were recorded. Necessary investigations like skin biopsy and patch testing was done wherever required.&lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; The maximum number of patients belong to the age group of 21-35 years with a female predominance (67.2%). Among patients of FM, post inflammatory pigmentation (35.3%) was the most common comprising of 362 patients, followed by melasma (17.2%), periorbital melanosis (15.7%), seborrheic melanosis (7.5%) followed by other causes.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; FM is common in Indian skin, several of which have overlapping features, and some have defined clinical classification. Additionally, climatic conditions, cosmetic usage and social parameters predispose to the increased incidence of FM.&lt;/p&gt;

Contact allergen sensitivity in children with contact dermatitis.

Irritant contact dermatitis and Allergic contact dermatitis are two distinct forms of contact dermatitis. Allergic contact dermatitis is a Type 4 (delayed-type) hypersensitivity reaction that occurs during subsequent contact with an allergen to a previously sensitized person. The number of allergens that cause allergic contact dermatitis is increasing day by day. Although it is not the gold standard for the detection of these allergens, skin patch testing is a very helpful method. This study aimed to determine the most common contact allergens in the pediatric age group. All patients with the diagnosis of contact dermatitis who underwent a skin patch test (TRUE TEST) in the department of Pediatric Allergy and Immunology between March 2017-February 2018 were enrolled in this study. The patch test was evaluated 72 hours later by the same physician and interpreted as recommended by the American Academy of Dermatology. In addition to the patient files, demographic and clinical characteristics, localization of lesions, and itch score according to visual analog scale were recorded. A total of 80 children enrolled in the study; 45 (56.3%) were girls and 35 (43.7%) were boys. The mean age of the children was 7.37±3.84 years and 57.5% of the patients who underwent skin patch testing had a positive response to at least one or more allergens. The most common allergens were Nickel sulfate, CI + Me-Isothiazolinone, Thiuram Mix, Formaldehyde, and P-tert-butylphenol formaldehyde resin (14.8%, 10%, 6.3%). There was no difference in terms of age, sex, duration of complaints, and pruritus score according to nickel sensitization. In the presence of chronic dermatitis in children, allergic contact dermatitis should be considered in the differential diagnosis. The culprit allergen should be determined. Also, the most common contact allergen is Nickel Sulphate in the world and the increased sensitization to other allergens is due to the increased contact of children with cosmetics and different contact allergens.

Carmine allergy in urticaria patients.

IntroductionCarmine, a commonly used natural red dye, can cause immediate and delayed allergic reactions, which are frequently overlooked.AimTo assess the incidence of carmine allergy and its clinical significance based on the placebo-controlled oral challenge in urticaria patients and suspected hypersensitivity to food additives.Material and methodsPatients’ histories were recorded by means of a standardized questionnaire. The subjects underwent skin prick tests and patch tests for carmine, while the level of specific IgE was measured in 52 patients. The patients with at least one positive carmine test or with suspected hypersensitivity to carmine were suggested to undergo a placebo-controlled oral challenge test.ResultsOne hundred and ten patients were enrolled in the study. Carmine skin testing was positive in 22 patients: skin prick tests were positive in 17% (n = 19), while patch tests were doubtful in 6% (n = 6). In 25/52 patients, the level of specific IgE was min. 0.01 kU/l. Oral challenge was performed in 33 subjects. Allergy to carmine was diagnosed in 9 (8%) patients; all of them suffered from chronic inducible urticaria.ConclusionsCarmine is a potential allergen in patients with chronic inducible urticaria especially with concomitant systemic symptoms. Skin tests and specific IgE level measurement may be helpful tools to diagnose E120 hypersensitivity.

The Significance of Metal Sensitivity Testing in Instrumented Orthopaedic Surgery

» A review of the incidence and clinical significance of metal hypersensitivity to better understand the role for testing in the detection and prevention of allergic reactions to orthopedic implants.» Orthopedic procedures involving metallic implants are increasingly common with projected future growth.» Allergic reactions to metallic implants have been extensively reported, but debate remains regarding the clinical impact of metal induced allergic reactions following orthopedic device implantation.» There is no generally accepted standard for testing to detect metal hypersensitivity in patients who are considering implantation of a prosthetic device or who already have a device in place.» Available testing options to detect metal hypersensitivity typically include skin patch testing and the lymphocyte transformation, which differ in sensitivity, cost, and convenience.» Current research suggests that preoperative testing may be a safe and cost-effective way to improve outcomes in select patients and reduce the need for revision surgery.

Comparison of transepidermal water loss rates in subjects with skin patch test positive vs negative to skin care products

Adverse cutaneous reactions to skin care products (SCP) are becoming increasingly common and may be indicative of defective permeability barrier function. To determine the differences in transepidermal water loss rates (TEWL) between skin patch positive vs negative to skin care products in normal Chinese females. Skin patch test reactions to nine skin care products were assessed in 65 normal Chinese females. Correlations of cutaneous reactions to a panel of nine foreign and domestic SCP with permeability barrier function and stratum corneum (SC) hydration levels were analyzed. Out of 65 subjects, 24 (37%) displayed positive reactions to one or more SCP. However, the occurrence of positive reactions to patch tests did not correlate with either transepidermal water loss rates or SC hydration levels. Though a substantial proportion of normal females display adverse reactions to SCP, this problem cannot be attributed to differences in the qualities of their epidermal permeability barriers, and therefore, these reactions more likely reflect the potential adverse events of the SCP themselves. However, further studies in large cohort of both males and females would be helpful to ascertain whether TEWL levels can predict cutaneous reactions to SCP.

Exploring therapeutic potential of azelaic acid loaded NLCs for the treatment of acne vulgaris

Azelaic acid (AZA), a naturally occurring dicarboxylic acid is reported to be effective in management of mild to moderate acne vulgaris. However, incidence of dose-related side effect limits its therapeutic applicability. The study is an endeavour to establish the anti-acne potential of pre-formulated and optimized Azelaic acid (AZA) loaded nano-structured lipid carriers (NLCs). The current investigation comprise of characterization of optimized nano preparation (NLCs suspension) or nano formulation (aloe-vera based nanogel) for its skin retentability, skin compatibility, anti-inflammatory, cytotoxicity and anti-microbial potential. Confocal laser scanning microscopic (CLSM) studies of skin revealed an intense fluorescence concentrated over the deeper layers of the skin, in comparison to superficial fluorescence of marketed preparation, indicating the superior carrier abilities of NLCs to the target site (epidermal-dermal junction). No signs of redness, dryness/oedema was observed for AZA NLCs in Draize skin patch test and the results were comparable to that of control. Cytotoxicity studies conducted employing Saccharomyces cerevisiae model also demonstrated a negligible cell death (<10%) upon application of nano preparation, confirming their biocompatible nature. The topical application of nano-preparation on P.acnes infected mice ear, suggested its anti-inflammatory and antimicrobial properties. Thus, above studies highlighted NLCs gel to be a promising vehicle for enhancing the tissue targetability and efficacy of AZA without compromising its safety and therapeutic profile.

Contact Sensitization in Patients with Chronic Leg Ulcers: Results of a 5-Year Retrospective Analysis.

To determine the frequency of contact sensitization among patients with chronic leg ulcers; to identify the most common allergens; and to examine possible relationships to ulcer duration, itching, exudate, and leg eczema. Researchers conducted a 5-year retrospective analysis of 145 patients diagnosed with chronic leg ulcers who underwent skin patch testing with S-1000, LU-1000, and the commonly used dressing and antiseptic series. Investigators included 88 females (60.7%) aged 64 ± 15.1 years and 57 males (39.3%) aged 61 ± 16.4 years. Of these, 62.8% (n = 91) of patients were sensitized to at least one substance (2.6 ± 1.4 allergens on average). The most common allergens were benzalkonium chloride (18.6% [n = 27]), balsam of Peru (17.9% [n = 26]), and povidone-iodine 10% (17.2% [n = 25]). Finally, 40% (n = 58) of patients presented with pruritus around the ulcer, which was strongly associated with a positive patch test reaction (74.1% [n = 43] vs 55.2% [n = 48]; P = .021) and polysensitization (3.5 sensitivities [95% confidence interval, 2.4-4.6] vs 2 [95% confidence interval, 1.2-2.8]). Contact sensitization is very common in patients with chronic leg ulcers, and pruritus around the ulcer is associated with contact allergy as well as polysensitization.

A mysterious rash around surgical wounds

Introduction Contact dermatitis (CD) that occurs shortly after a surgery is often caused by a direct irritant effect of medical products or, infrequently, a delayed type hypersensitivity. Various agents have been reported to cause CD including topical medications, surgical instruments, and surgical glue. We present a patient who developed rash around surgical wounds. Skin patch testing identified the causative agent of his CD. Case Description A 15-year-old male presented with new onset of pruritic papulovesicular rash three weeks following Nuss procedure, a minimally invasive pectus excavatum repair using a metal bar. The rash initially appeared on upper extremities and chest wall around surgical wounds (Figure 1A). Later, new erythematous lesions occurred on foreskin of penis. Patient denied other systemic symptoms or prior history of metal or medication allergy. A delayed hypersensitivity to nickel or other components of stainless steel used in the pectus bar was suspected. Surgical removal of the bar was contemplated. A trial of oral prednisone 30mg BID led to resolution of the rashes (Figure 1B). Blood test for metal-lymphocyte proliferation assay was unremarkable. Skin patch test was negative to nickel and metal disc, and confirmed a reaction to 2-octyl cyanoacylate (surgical glue) (Figure 1C). Discussion Delayed-type hypersensitivity to surgical glue should be considered in patients who develop rash around surgical wounds. Evaluation of surgery-related CD requires a thorough understanding of procedure steps and potential exposures to medical products. Patch test can aid in identification of the offending agent and allow a recommendation of alternative products to avoid recurrence. Figure. A. Rash around surgical wounds Figure 1B. Improvement of rash after a 5-day course of prednisone 30 mg BID treatment Figure 1C. Positive patch test to 2-octyl cyanoacrylate (Dermabond® surgical glue)

073 Epicutaneous sensitization with protein allergens differentiates naïve T cells into not only Th2 but also Th17 cells, which may involve in the delayed reactions in protein contact dermatitis

Protein contact dermatitis (PCD) is caused by proteins. The patients may show positive immediate or delayed reactions in skin prick, scratch or patch test, or the skin tests may remain negative. Specific IgE is obviously crucial in most reactions, however, the exact mechanisms remains unclear. To address these issues, we investigated mice sensitized by papain enzyme as a protein allergen. Mice were sensitized by 24hrs exposure to papain twice a week for one month. The draining lymph node cells were then isolated and re-stimulated by papain. ELISA and FACS analyses of the cytokines synthesized in lymph node cells revealed that CD4+ IL4+ T (Th2) and CD4+ IL17+ T (Th17) cells were differentiated in the draining lymph nodes of the mice sensitized by papain. However, CD4+ IFN-gamma+ T cells (Th1) were not detected. The sensitized mice were elicited by applying papain onto the ear to address the role of Th2 and Th17 cells differentiated in the papain-sensitized mice, and the allergic reactions in the ear were examined. Real-time PCR analyses revealed that IL-17 mRNA of Th17 marker was up-regulated in a time-dependent manner; however, IL-4 mRNA of Th2 maker was not detected at any time points. These phenomena were confirmed by immunofluorescent microscopy using a specific antibody for IL-17, suggesting that Th17, but not Th2, migrated into the ear after the elicitation. Additionally, the papain-sensitized mice possessed papain-specific IgE, and mast cell degranulation was observed after the elicitation. These findings reveal for the first time that the sensitization of papain enzyme differentiates naïve T cells into not only Th2 but also Th17 cells as effector T cells contributing to the allergic reactions. The generated Th2 produces IL-4 and is involved in IgE syntheses in the draining lymph nodes. Conversely, the generated Th17 cells migrate to the skin and produce IL-17 after elicitation, which may involve in the delayed reactions of PCD.

Application of transdermal patches with new skin test reagents for detection of latent tuberculosis.

Introduction. Current intradermal tuberculin skin tests for latent tuberculosis infection (LTBI) based on purified protein derivative (PPD) have poor specificity.Aims. Developing a better skin test antigen as well as a simple skin patch test may improve and facilitate diagnostic performance.Methodology. Defined recombinant antigens that were unique to Mycobacterium tuberculosis (MTB), including two potential latency-associated antigens (ESAT-6 and Rv2653c) and five DosR-encoded latency proteins (Rv1996, Rv2031c, Rv2032, DevR and Rv3716c), were used as diagnostic skin test reagents in comparison with a standard PPD. The performance of the skin tests based on the detection of delayed-type hypersensitivity (DTH) reaction in guinea pigs sensitized to MTB and M. bovis bacille Calmette-Guérin (BCG) vaccine was evaluated.Results. The latency antigens Rv1996, Rv2031c, Rv2032 and Rv2653c and the ESAT-6 protein elicited less reactive DTH skin responses in MTB-sensitized guinea pigs than those resulting from PPD, but elicited no response in BCG-vaccinated guinea pigs. The remaining two latency antigens (DevR and Rv3716c) elicited DTH responses in both groups of animals, as did PPD. The reactivity of PPD in BCG-vaccinated guinea pigs was greater than that of any of the selected skin test reagents. Using stronger concentrations of selected skin test reagents in the patch test led to increased DTH responses that were comparable to those elicited by PPD in guinea pigs sensitized with MTB.Conclusion. Transdermal application of defined purified antigens might be a promising method for LTBI screening.

Diagnosis of Feline Food Sensitivity and Intolerance Using Saliva: 1000 Cases.

Simple SummaryThis study asked whether a novel saliva-based diagnostic test could predict food sensitivities and intolerances in cats. Clinical samples were obtained from 1000 cats proven or suspected to have adverse food reactions (AFR). Most were domestic shorthairs over 10 years old and weighed around 5 kg; they were equally distributed between spayed females and neutered males. Saliva was collected after at least an 8-h fast with a dental cotton rope, placed in a special saliva collection tube, and sent to the laboratory. Salivary reactions to 24 common foods were measured with immunological reagents. Low reacting foods were lamb, cow milk, pork, turkey, wheat (lowest) and white-colored fish, whereas high reacting foods were millet, white potato, rice (highest) and salmon. Thus, this novel salivary-based food sensitivity and intolerance test, described previously for dogs, also provided a reliable and clinically predictive alternative to other methods of measuring AFR in cats.This prospective study assessed the efficacy of a novel saliva-based immunoassay of IgA- and IgM-antibodies in predicting feline food sensitivities and intolerances. Clinical samples were obtained from 1000 cats proven or suspected to have food intolerances. Most were of domestic shorthair breed type, over 10 years of age, and weighed around 5 kg; they were equally distributed between spayed females and neutered males. Saliva was collected after at least an 8-h fast with a dental cotton rope, placed in a double-sleeved saliva collection tube, and sent to the laboratory. Salivary antibodies elicited by 24 common foods were measured with goat anti-canine IgA and IgM. Low reacting foods were lamb, cow milk, pork, turkey, wheat (lowest) and white-colored fish, whereas high reacting foods were millet, white potato, rice (highest) and salmon. Thus, the novel salivary-based food sensitivity and intolerance test, described previously for canines, also provided a reliable and clinically predictive alternative to food elimination trials, serum-based food allergy testing, and skin patch testing in cats. Manufacturers of commercial cat foods and treats, as well as those making homemade diets and treats for cats, should consider avoiding the more highly reactive foods as determined by the present study.