Influence of a single oral dose of trazodone on intradermal histamine reactivity in clinically healthy dogs.

BACKGROUND: Drug interactions are significant considerations for intradermal testing (IDT). Trazodone (TRZ) is an anxiolytic and selective histaminergic (H1 ) antagonist with no interaction in human prick tests; however, interaction in canine IDT is unknown. HYPOTHESIS/OBJECTIVES: Trazodone will not adversely affect intradermal histamine reactions in dogs. ANIMALS: Fourteen nonanxious, nonatopic, healthy client-owned dogs were enrolled in this randomised, blinded, cross-over study. MATERIALS AND METHODS: Dogs were randomised to receive low-dose TRZ (4 mg/kg) (Teva Pharmaceuticals), high-dose TRZ (8 mg/kg) or no TRZ per os two hours before intravenous sedation with dexmedetomidine (5 mcg/kg) (Dexdomitor; Zoetis). Intradermal testing was performed with five quadrupling dilutions of histamine (1:100,000 to 1:25,600,000 w/v; Greer) and 0.9% saline (Hospira), observing a minimum two weeks washout period between treatments. Two observers, who were blinded to treatment and the identity of the injections, evaluated each test using previously established subjective and objective methods. RESULTS: The mean wheal diameter of histamine 1:1,600,000 w/v was significantly smaller with low-dose TRZ (4 mg/kg) compared to the control group (p = 0.048; repeated measures ANOVA with post hoc Tukey's test). For all other histamine dilutions and saline, mean wheal diameter was not significantly different among groups. There were no significant differences in the subjective scores of all histamine dilutions and saline (p > 0.05; Friedman test). CONCLUSION AND CLINICAL RELEVANCE: A single oral dose of TRZ does not adversely affect intradermal histamine reactions in dogs.

A randomised, double-blinded trial to assess the effect of oclacitinib and prednisolone on intradermal allergen and prick tests in dogs with atopic dermatitis.

BACKGROUND: Intradermal (IDT) and prick (PT) tests are used to select allergens for allergen-specific immunotherapy in dogs with atopic dermatitis (cAD). However, the use of antipruritic drugs before performing these tests may influence the results. OBJECTIVE: To evaluate the influence of the drugs oclacitinib and prednisolone on the immediate-phase reactions of IDT and PT. ANIMALS: Thirty client-owned dogs with cAD with positive reactions to at least one allergen extract on IDT or PT. MATERIALS AND METHODS: Dogs were randomly assigned to receive oclacitinib 0.4-0.58 mg/kg per os, every 12 h (n = 14), or prednisolone 0.37-0.65 mg/kg p.o., every 12 h (n = 16) for 14 days. IDT and PT were performed on Day (D)0 before treatment and on D14. RESULTS: At D14 there was no significant reduction in the means of the orthogonal diameters of the positive immediate-phase reactions of the IDT (p = 0.064) in the oclacitinib group; however, in the PT, the diameter of the positive reactions reduced significantly (p = 0.048). In both tests, there was no significant reduction in the total number of positive reactions (IDT, p > 0.999; PT, p = 0.735). In the prednisolone group, the means of the orthogonal diameters of positive immediate-phase reactions were significantly reduced in both tests (IDT, p = 0.001; PT, p ≤ 0.001) and there also was a reduction in the total number of positive reactions (IDT, p = 0.022; PT, p = 0.001). CONCLUSIONS AND CLINICAL RELEVANCE: The use of oclacitinib 0.4-0.58 mg/kg twice daily for 14 days does not interfere with IDT results in dogs with cAD. However, oclacitinib may reduce PT reactivity. The use of prednisolone 0.37-0.65 mg/kg twice daily results in a reduction in both IDT and PT results.

Cutaneous anaphylactoid reaction to polyoxyethylene hydrogenated castor oil in dogs.

BACKGROUND: Polyoxyethylene hydrogenated castor oil (HCO ethoxylates) is a nonionic surfactant used as an excipient for ointments and injections in human and veterinary drugs. Several polyethylene glycol (PEG) derivatives can be obtained depending on the number of moles of ethylene oxide (EO). HCO ethoxylates have the potential to cause anaphylactoid reactions. There is little published information about these types of reactions in dogs. OBJECTIVE: To determine the potential for HCO-ethoxylate-containing drugs to cause anaphylactoid reactions in dogs, employing intradermal testing (IDT) with various concentrations of HCO ethoxylates (HCO-25, -40, -60 and -80). ANIMALS: Four healthy male laboratory dogs. MATERIALS AND METHODS: We performed IDT with drugs containing HCO ethoxylates and HCO ethoxylates alone to determine threshold concentrations. The IDT scores and threshold concentrations were compared. Analysis of skin biopsies from IDT sites was used to measure the percentage of degranulated mast cells. The effect of histamine at IDT sites was investigated by pre-treatment with an antihistamine. RESULTS: All HCO-ethoxylate-containing drugs caused a wheal-and-flare reaction. The threshold concentrations (0.001% and 0.00001%) of each HCO-ethoxylate depended on the number of moles of EO (p < 0.05). Mast cell degranulation was enhanced by all HCO ethoxylates. The HCO-60-induced reaction was suppressed by an oral antihistamine. CONCLUSIONS AND CLINICAL RELEVANCE: The threshold concentration can serve as a consideration for developing safe new drug formulations and for clinical decision-making around using drugs containing PEG derivatives. IDT is useful to predict the risk of adverse effects. Antihistamines could demonstrate a prophylactic effect.

Comparison of intradermal and serum testing for environmental allergen-specific immunoglobulin E determination in a laboratory colony of cats with naturally acquired atopic syndrome.

BACKGROUND: Allergen testing is used to select antigens included in the desensitisation vaccine. Intradermal skin test (IDT) is the gold standard in cats, yet allergen-specific immunoglobulin (Ig)E serological testing (ASIS) is often used. Feline data are lacking regarding the agreement between IDT and ASIS results. HYPOTHESIS/OBJECTIVES: The first objective of the study was to establish a colony of cats with naturally acquired feline atopic syndrome (FAS). Further objectives were to define their hypersensitivity disorder to detail the allergen tests results, and to assess similarity between the allergen tests. ANIMALS: Thirty-five cats with FAS and 10 control cats. MATERIALS AND METHODS: Enrolled cats went through a five phase-screening and quarantine process before joining the colony. An elimination diet trial was performed on all FAS cats. ASIS and IDT were consecutively performed on all cats under sedation. RESULTS: Reactions to 34 allergens were compiled for the 45 cats. Global sensitivity and specificity of ASIS were 34.7% and 78.9%, respectively. Only flea (ICC = 0.26, p = 0.040) and Dermatophagoides pteronyssinus (ICC = 0.48, p < 0.001) allergens had a significant intraclass correlation (weak agreement). Two FAS cats had negative tests including one cat with a concomitant food allergy. CONCLUSIONS AND CLINICAL RELEVANCE: This study depicts the first reported colony of cats with naturally acquired FAS. This is the first feline study to compare and show the poor agreement between allergen tests with a panel of 34 allergens. This colony also harbours two cats with FAS with negative allergen tests. These may represent the first described cats with an intrinsic form of atopic syndrome.

Effect of glycerin on immediate cutaneous reactions of histamine (positive) and phosphate-buffered saline (negative) controls in intradermal skin testing of healthy dogs: A randomised, blinded study.

BACKGROUND: Glycerinated allergen extracts contain 50% glycerin, an excellent preservative. While glycerin is a recognised irritant in humans, the utility of glycerinated extracts for intradermal testing has not been validated in dogs. HYPOTHESIS/OBJECTIVE: To determine and compare the effects of glycerin on immediate cutaneous reactions to intradermal injections of histamine and saline in healthy dogs. ANIMALS: Eight healthy laboratory beagles. MATERIALS AND METHODS: The study was designed as a randomised, blinded study. Intradermal injections of histamine (positive control) and saline (negative control) in aqueous and glycerinated (50%) forms were performed on the right thorax. Global wheal scores (GWS) at 20 min were evaluated by two independent investigators blinded to the interventions. RESULTS: There were no wheal and flare reactions observed after the intradermal injections of phenolated saline. By contrast, 50% glycerosaline injections induced erythema and induration in all dogs. Global wheal scores were significantly higher in aqueous histamine (Friedman test, p < 0.0001) and 50% glycerinated histamine (Friedman test, p = 0.0084) compared to phenolated saline controls. Interestingly, only aqueous histamine (Friedman test, p = 0.01) had significantly higher GWS than 50% glycerosaline injections, while no significant difference in GWS between 50% glycerinated histamine and 50% glycerosaline groups was observed (Friedman test, p = 0.59). CONCLUSION AND CLINICAL RELEVANCE: This study demonstrates that intradermal injection of 50% glycerosaline induces erythema and induration skin reactions in healthy dogs that can mimic positive reactions to allergenic extracts. Further dilutions of glycerinated positive and negative control solutions need to be optimised for intradermal testing in dogs.

Investigation of the diagnostic performance of prick test with two environmental allergens in dogs with atopic dermatitis: A study using intradermal test as the gold standard.

BACKGROUND: There are no studies investigating the correlation between prick test (PT) and intradermal test (IDT) with environmental allergens in dogs with atopic dermatitis (AD). OBJECTIVES: To investigate the correlation between PT and IDT for two environmental allergens, and to calculate the sensitivity, specificity and Youden index of PT, using IDT as the gold standard. MATERIALS AND METHODS: Twenty-two dogs with AD were selected. PT was performed with glycerinated allergen extracts, along with negative and positive controls, using the Greer Prick System. Reactions were interpreted (positive/negative) subjectively and by using seven objective criteria, by an examiner blinded to the IDT results. IDT reactions to the same allergens were interpreted, subjectively and objectively, by another masked investigator. The agreement between PT and IDT, the sensitivity, specificity and Youden index of PT, using IDT as gold standard, were calculated. RESULTS: On subjective evaluation, the correlation between PT and IDT was poor and sensitivity of PT was 0%. Of the seven criteria for the objective evaluation of PT, the best diagnostic performance was attained when allergen-induced wheals were considered positive if their longest diameter was ≥8.5 mm. However, even then, the correlation with IDT was moderate, and the sensitivity of PT, albeit based on few positive IDT reactions, was low. CONCLUSION AND CLINICAL RELEVANCE: At least as performed herein, PT has a poor-to-moderate correlation with IDT, mainly as a consequence of the lack of positive PT reactions. Further studies are needed to improve PT technique, yet, meanwhile, it cannot be recommended as a substitute for IDT.

Pilot study to determine the concordance between skin prick and intradermal test (IDT) reactivity to environmental allergens in atopic dogs using IDT as the gold standard.

BACKGROUND: Prick testing is widely used as the first-line in vivo test for environmental allergens in people owing to its noninvasive nature and speed of performance. OBJECTIVES: To determine concordance between skin prick testing (SPT) and intradermal testing (IDT) reactivity to environmental allergen mixes in dogs with atopic dermatitis (cAD). ANIMALS: Forty client-owned dogs with cAD. MATERIALS AND METHODS: Skin prick testing (GREER Pick System; Stallergenes Greer) and IDT were performed on 40 dogs using seven glycerinated and aqueous environmental allergen mixes, respectively (tree, grass and weed pollens, house dust mites and three mould mixes). Reactions for IDT and SPT were evaluated both subjectively and objectively (mean wheal diameter; MWD) and compared to saline and histamine controls. RESULTS: Using IDT as the gold standard, with subjective scoring, SPT was 47.0% sensitive [95% confidence interval (CI) 36.0%-58.7%], 92.1% specific (95% CI 87.6%-95.3%) and agreement was moderate (79%, Cohen's kappa = 0.424). The positive predictive value of SPT was 36% and negative predictive value was 95%. Objective and subjective scores had only fair agreement. CONCLUSIONS AND CLINICAL RELEVANCE: Skin prick testing with allergen mixes was specific yet poorly sensitive as compared to IDT. For both IDT and SPT, 95% (38 of 40) dogs failed to react to an allergen mix, despite showing a positive reaction to at least one component. Future studies comparing SPT and IDT should test individual allergens rather than mixes to prevent the dilution of individual components, which may have resulted in false negatives.

Repeatability and reproducibility of the interpretation of intradermal test results in dogs with atopic dermatitis.

Background - There is lack of studies evaluating the repeatability and reproducibility of the interpretation of intradermal testing in dogs with atopic dermatitis (AD). Objectives - To evaluate the repeatability and reproducibility of the interpretation of intradermal test results in dogs with AD. For comparison, the repeatability of allergen-specific immunoglobulin (Ig)E serology also was examined. Materials and methods - Twenty dogs with AD were used. Intradermal test included injections of known negative and positive controls, and of 25 masked injections of 10 allergens/controls, that were selected randomly and injected at random positions. Reactions to the 25 masked allergens/controls were scored (positive/negative) subjectively by three independent examiners followed by an objective assessment. Allergen-specific IgE serology was performed in blinded duplicate samples collected from all dogs for nine of 10 of the same allergens. Results - Kappa values of intraobserver repeatability (≥2 injections of the same allergen to different positions of the same dog) varied between -0.53 and 0.8 (subjective evaluations), and between 0.03 and 1 (objective evaluation). When the repeatability of the serological test was examined k = 0.91. Kappa values for the interobserver reproducibility (objective and three subjective evaluations of the same allergen injected at the same position of the same dog) varied between 0.6 and 0.74 (overall 0.67). Conclusions and clinical relevance - Intraobserver repeatability of the subjective and objective evaluation of IDT results varied from good to poor and depended on the number of times the same allergen was injected, whereas interobserver reproducibility varied from substantial to moderate. Further studies are needed to optimise the repeatability and reproducibility of IDT in dogs.

Contexte - Il existe un manque d'études évaluant la répétabilité et la reproductibilité de l'interprétation des tests intradermiques chez les chiens atteints de dermatite atopique (DA). Objectifs - Évaluer la répétabilité et la reproductibilité de l'interprétation des résultats des tests intradermiques chez les chiens atteints de MA. À des fins de comparaison, la répétabilité de la sérologie de l'immunoglobuline (Ig)E spécifique de l'allergène a également été examinée. Matériels et méthodes - Vingt chiens atteints de MA ont été utilisés. Le test intradermique comprenait des injections de contrôles négatifs et positifs connus, et de 25 injections masquées de 10 allergènes/contrôles, qui ont été sélectionnés au hasard et injectés à des positions aléatoires. Les réactions aux 25 allergènes/contrôles masqués ont été notées (positives/négatives) subjectivement par trois examinateurs indépendants, suivies d'une évaluation objective. La sérologie IgE spécifique de l'allergène a été réalisée dans des échantillons en double en aveugle prélevés sur tous les chiens pour neuf des 10 allergènes identiques. Résultats - Les valeurs kappa de répétabilité intra-observateur (≥2 injections du même allergène à différentes positions du même chien) variaient entre -0,53 et 0,8 (évaluations subjectives), et entre 0,03 et 1 (évaluation objective). Lorsque la répétabilité du test sérologique a été examinée, k = 0,91. Les valeurs de Kappa pour la reproductibilité interobservateur (évaluations objective et trois évaluations subjectives du même allergène injecté au même endroit du même chien) variaient entre 0,6 et 0,74 (globalement 0,67). Conclusions et pertinence clinique - La répétabilité intra-observateur de l'évaluation subjective et objective des résultats IDT variait de bonne à mauvaise et dépendait du nombre d'injections d'un même allergène, alors que la reproductibilité inter-observateur variait de substantielle à modérée. D'autres études sont nécessaires pour optimiser la répétabilité et la reproductibilité de l'IDT chez le chien.

Introducción- faltan estudios que evalúen la repetibilidad y la reproducibilidad de la interpretación de las pruebas intradérmicas en perros con dermatitis atópica (AD). Objetivos- evaluar la repetibilidad y reproducibilidad de la interpretación de los resultados de las pruebas intradérmicas en perros con AD. A modo de comparación, también se examinó la repetibilidad de la serología de inmunoglobulina (Ig)E específica de alérgeno. Materiales y métodos - Se utilizaron 20 perros con AD. La prueba intradérmica incluyó inyecciones de controles positivos y negativos conocidos, y de 25 inyecciones enmascaradas de 10 alérgenos/controles, que se seleccionaron al azar y se inyectaron en posiciones aleatorias. Las reacciones a los 25 alérgenos/controles enmascarados fueron calificadas (positivas/negativas) subjetivamente por tres examinadores independientes seguido de una evaluación objetiva. La serología de IgE específica para alérgenos se realizó en muestras duplicadas ciegas recolectadas de todos los perros para nueve de 10 de los mismos alérgenos. Resultados - Los valores Kappa de repetibilidad intraobservador (≥2 inyecciones del mismo alérgeno en diferentes posiciones del mismo perro) variaron entre -0,53 y 0,8 (evaluaciones subjetivas) y entre 0,03 y 1 (evaluación objetiva). Cuando se examinó la repetibilidad de la prueba serológica k = 0,91. Los valores de Kappa para la reproducibilidad interobservador (objetivo y tres evaluaciones subjetivas del mismo alérgeno inyectado en la misma posición del mismo perro) variaron entre 0,6 y 0,74 (en general, 0,67). Conclusiones y relevancia clínica- la repetibilidad intraobservador de la evaluación subjetiva y objetiva de los resultados de la IDT varió de buena a mala y dependió del número de veces que se inyectó el mismo alérgeno, mientras que la reproducibilidad interobservador varió de sustancial a moderada. Se necesitan más estudios para optimizar la repetibilidad y reproducibilidad de IDT en perros.

Contexto - Há poucos estudos avaliando a repetibilidade e reprodutibilidade da interpretação do teste intradérmico em cães com dermatite atópica (DA). Objetivos - Avaliar a repetibilidade e reprodutibilidade da interpretação dos resultados de testes intradérmicos em cães com DA. Para comparação, a repetibilidade da sorologia com imunoglobulinas (Ig)E alérgeno-específicas foi também avaliada. Materiais e métodos - Foram utilizados 20 cães com DA. O teste intradérmico incluiu injeções de controles negativos e positivos conhecidos e de 25 injeções mascaradas de 10 alérgenos/controles, que foram selecionados aleatoriamente e injetadas em posições aleatórias. As reações aos 25 alérgenos/controles mascarados foram pontuadas (positiva/negativa) subjetivamente por três examinadores independentes, seguidas de uma avaliação objetiva. A sorologia de IgE específica para alérgenos foi realizada em amostras duplicadas cegas coletadas de todos os cães para nove de 10 dos mesmos alérgenos. Resultados - Os valores Kappa de repetibilidade intraobservador (≥2 injeções do mesmo alérgeno em diferentes posições do mesmo cão) variaram entre -0,53 e 0,8 (avaliação subjetiva) e entre 0,03 e 1 (avaliação objetiva). Quando examinada a repetibilidade do teste sorológico k=0,91. Os valores de Kappa para a reprodutibilidade interobservador (objetiva e três avaliações subjetivas do mesmo alérgeno injetado na mesma posição do mesmo cão) variaram entre 0,6 e 0,74 (total 0,67). Conclusões e relevância clínica - A repetibilidade intraobservador da avaliação subjetiva e objetiva dos resultados do IDT variou de boa a ruim e dependeu do número de vezes que o mesmo alérgeno foi injetado, enquanto a reprodutibilidade interobservador variou de substancial a moderada. Mais estudos são necessários para otimizar a repetibilidade e reprodutibilidade do IDT em cães.

THE USE OF INTRADERMAL SKIN TESTING AND HYPOSENSITIZATION INJECTIONS TO CONTROL SEASONAL DERMATITIS IN GREATER ONE-HORNED RHINOCEROSES (RHINOCEROS UNICORNIS).

Allergic dermatitis was diagnosed in a 25-yr-old female greater one-horned rhinoceros (Rhinoceros unicornis) and her 6-yr-old female offspring by skin biopsy, intradermal skin testing (IDST), and allergen-specific serum IgE testing. Dam and offspring presented with seasonal, erosive, and ulcerative dermatitis affecting the face, legs, and trunk starting at 6 and 2 yr of age, respectively. IDST was performed at the caudal pinnal base using 61 regionally specific allergens. Specific serum allergen responses were detected using Heska's Equine ALLERCEPT® Allergen Panel. Histopathology of the lesions was consistent with an allergic etiology. Injectable allergen-specific immunotherapy was initiated in both animals and within 6 to 18 mon after commencing hyposensitization clinical improvement was noted. This report documents a repeatable methodology for IDST and serological allergen testing for use in rhinoceroses. The hyposensitization protocol detailed here can help guide future treatment protocols.

Pilot study of dogs with suppurative and non-suppurative Malassezia otitis: A case series.

BACKGROUND: Rarely, Malassezia otitis presents as a painful, erosive otitis with an otic discharge containing Malassezia and neutrophils on cytology. There are no published reports of this type of suppurative Malassezia otitis (SMO). The role of Malassezia hypersensitivity in otitis is still unknown, and no association has been demonstrated with SMO. We compared Malassezia IgE levels, intradermal test and histology changes in SMO dogs with the more conventional Malassezia otitis (MO) presentation. RESULTS: Three dogs (case 1, case 2 and case 3) were diagnosed with SMO, one dog (case 4) was diagnosed with unilateral MO and unilateral SMO, and one dog (case 5) was diagnosed with MO. Only one case (case 4) with SMO/MO had a positive Intradermal Allergy Test (IDAT) and elevated IgE levels for Malassezia. Histopathology findings from SMO revealed: interface dermatitis (case 1 and 3), lymphocytic dermatitis (case 2) and chronic hyperplastic eosinophilic and lymphoplasmacytic dermatitis (case 4). Histopathology findings from MO showed perivascular dermatitis (case 4 and 5). All the cases were treated successfully. CONCLUSIONS: SMO presents with a distinct clinical phenotype in comparison with conventional MO. No consistent aetiology could be isolated. In these clinical cases it is possible that previous treatments could have influenced the results. More research is needed to understand the possible aetiologies and the pathogenesis of SMO.

The effect of topical lidocaine on intradermal testing in atopic dogs.

BACKGROUND: Intradermal testing (IDT) most often requires sedation. Topical lidocaine offers an adjunct or alternative to sedation. HYPOTHESIS/OBJECTIVES: We hypothesized that topical lidocaine would significantly reduce reactions to intradermal injections and that atopic dogs treated with topical lidocaine would have similar results with IDT to atopic dogs tested without topical lidocaine. ANIMALS: Fifteen client-owned atopic dogs. METHODS: In Part I, a 5% lidocaine patch, 5% lidocaine cream and a control with no active ingredients were compared. The lowest pain score during intradermal injection was established in six atopic dogs. Fifteen atopic dogs were enrolled in Part II, and lidocaine cream (found to be most effective in Part 1) was applied randomly to a single side of the thorax. An IDT was performed on each side of the chest. Subjective and objective scores of the control and lidocaine treatment sides were compared 15 and 30 min post-injection. RESULTS: The 5% lidocaine cream had the greatest reduction in pain score associated with intradermal injection. There were no significant differences in mean wheal diameter for any evaluated allergen at any time point between the control and lidocaine-treated sides. There was high agreement between the two groups when assessing the subjective score for all but one allergen. CONCLUSIONS AND CLINICAL IMPORTANCE: Topical lidocaine may be used as adjunctive analgesia during IDT with caution in interpretation of subjective house dust scoring. Lidocaine cream appeared to reduce pain score and may allow reduction in concurrent sedation.

THE USE OF INTRADERMAL ALLERGY TESTING FOR ALLERGIC DERMATITIS IN PTEROPID BATS AND TREATMENT WITH ALLERGEN SPECIFIC IMMUNOTHERAPY: A CASE SERIES.

This case series describes the diagnosis of allergic dermatitis and management with allergen-specific immunotherapy (ASIT) based on intradermal allergy testing (IDAT) and adjunctive medical therapy in six pteropid bats; five large flying foxes (Pteropus vampyrus); and one variable flying fox (Pteropus hypomelanus). The cases ranged from 2 to 15 yr of age at the time of presentation. Clinical signs varied between individuals and included moist ulcerative cutaneous lesions in nonhaired skin, blepharoconjunctivitis, alopecia, and pruritus. All bats underwent IDAT under general anesthesia, and reactive allergens included a mixture of grasses, trees, weeds, and biting insects. Three of the six cases (50%) had reformulation of the ASIT before control of clinical signs was seen, and two bats were treated with the addition of oclacitinib (Apoquel). Severe adverse effects were not identified; however, one bat had self-limiting swelling at the immunotherapy injection site. All six cases showed improvement of clinical signs and perceived comfort level, including in subsequent allergy seasons.

Orchard grass allergy in an African spur-thighed tortoise (Centrochelys sulcata) confirmed via intradermal allergen testing and provocation testing.

The humoral immune system of reptiles is not well-studied. To the best of the authors' knowledge, this case report describes the first case of a type I allergic conjunctivitis associated with orchard grass in an African spur-thighed tortoise (Centrochelys sulcata) supported by intradermal allergen testing and provocative testing. Further studies are needed to better characterize allergic reactions in reptiles.

Le système immunitaire humoral des reptiles n'est pas bien étudié. A la connaissance des auteurs, cet article décrit le premier cas de conjonctivite associé au dactyle pelotonné chez une tortue sillonée (Centrochelys sulcata) confirmé par tests allergéniques intradermiques et test de provocation. Des études supplémentaires sont nécessaires pour mieux caractériser les réactions allergiques chez les reptiles.

El sistema inmunológico humoral de los reptiles no está bien estudiado. A entender de los autores, este artículo describe el primer caso de una conjuntivitis alérgica tipo I asociada con dáctilo (Dactylis glomerata) en una tortuga africana (Centrochelys sulcata) basado en pruebas de alérgenos intradérmicos y pruebas de provocación. Se necesitan más estudios para caracterizar mejor las reacciones alérgicas en reptiles.

O sistema imune humoral de répteis ainda não é bem estudado. De acordo com os conhecimentos dos autores, este relato descreve o primeiro caso de conjuntivite alérgica do tipo I associada a grama (Dactilys glomerata) em uma tartaruga-grega africana (Centrochelys sulcata) baseado em teste alérgico intradérmico e teste de provocação. Mais estudos são necessários para melhor se caracterizar as reações alérgicas em répteis.

Discrepancies in the bilateral intradermal test and serum tests in atopic horses.

BACKGROUND: In equine atopic patients intradermal testing (IDT) and immunoglobulin (Ig)E serology are used frequently. There is little evidence regarding the reproducibility of the IDT and IgE serology in horses. OBJECTIVES: To compare the results of a simultaneously performed IDT on the left and right side of the neck in atopic horses, and to compare these results with allergen-specific IgE serology. ANIMALS: Ten equine patients from a university hospital population with chronic urticaria and/or pruritus. METHODS AND MATERIALS: The IDT was performed using 16 allergens and the results were evaluated after 30 min, 1, 4 and 24 h. Thirteen allergens also were analysed in duplicate with two monoclonal allergen-specific IgE enzyme-linked immunosorbent assays (ELISA). RESULTS: Good agreement (Kappa > 0.6) between left and right IDT was found only for Dermatophagoides farinae, Lepidoglyphus destructor, birch pollen mixture and perennial rye at 30 min, birch pollen mixture at 1 h, and Acarus siro and nettle and common mugwort mixture at 4 h. The bilateral comparison of the other allergens and even the same allergens at other time points showed little or no concordance between left and right IDT. The interlaboratory comparison between both ELISAs, and the comparison between the ELISAs and IDT, showed a good agreement for two of 13 allergens: D. farinae and Dermatophagoides pteronyssinus. CONCLUSIONS AND CLINICAL IMPORTANCE: Based on these preliminary data, IDT and IgE serological test results should be interpreted with great care and further studies are needed to indicate the clinical relevance of these findings.

Correlation between carcass condemnations in slaughterhouses and official notifications of cattle testing positive for tuberculosis.

The objective of this study was to analyze the correlation between condemnations in slaughterhouses situated in Minas Gerais State and notifications to the Brazilian Official Veterinary Service of cattle that were positive for intradermal tuberculin tests. Data were obtained from three slaughterhouses under different surveillance conditions and from the Brazilian Agriculture and Livestock Health Agency for 2011 to 2017. During this period, there was an increase in the number of condemnations of females aged over 36 months, despite the number of females testing with intradermal tests and being reported as positive decreasing. Therefore, there is a discrepancy between the analyzed variables. Since there is a belief that slaughter condemnations can be used as tools for epidemiological surveys in beef and dairy farms, it is advisable for there to be a greater integration of the Brazilian Health Inspection Services in slaughterhouses and Brazilian Agriculture and Livestock defense department. This will ensure safe animal products.

CONSERVATION CHALLENGES: THE LIMITATIONS OF ANTEMORTEM TUBERCULOSIS TESTING IN CAPTIVE ASIATIC LIONS (PANTHERA LEO PERSICA).

Genetic diversity of captive wild animals can be enhanced by moving those individuals with valuable genes between collections and through introduction of a new pair from a range country. This requires movement of animals, which is inherent with disease risks, such as the introduction of pathogenic Mycobacterium sp. (MTBC) into a zoological collection. Decisions need to be made based on the outcome of perimovement disease screening using an array of tests, the majority of which are unvalidated in the species. A pair of endangered Asiatic lions (Panthera leo persica) imported from India to the United Kingdom were screened for MTBC using the comparative intradermal tuberculosis (TB) test, the feline interferon-γ blood test, and the experimental bacteriophage assay. Reactions on all three tests prompted screening of the three resident Asiatic lions using the same tests, all of which were negative for MTBC. Based on these test results, the decision had to be made to exclude the genetically valuable pair from the current collection. MTBC could not be identified using further tests, including culture and PCR on a bronchoalveolar lavage, on feces, or on postmortem tissues. This case series highlights the usefulness of a control group when interpreting unvalidated test results for detection of MTBC, the value of training big cats for conscious blood sampling, and the practical implications of placing the comparative intradermal TB test in the eyelids, when dealing with a species that requires a general anesthetic for most hands-on interventions.

Agreement of serum allergen test results with unblocked and blocked IgE against cross-reactive carbohydrate determinants (CCD) and intradermal test results in atopic dogs.

BACKGROUND: Tests for allergen-specific immunoglobulin E (IgE) are used to select allergens for immunotherapy in atopic dogs. Antibodies against cross-reactive carbohydrate determinants (anti-CCD IgE) have been identified in serum samples of atopic dogs. Their presence in humans is a known cause of clinically irrelevant polysensitization to plant allergens. OBJECTIVES: To compare the results of an intradermal test (IDT) and a serum test for allergen-specific IgE, with and without blocking anti-CCD IgE, before testing in dogs. ANIMALS: Thirty-one privately owned dogs with atopic dermatitis. METHODS AND MATERIALS: Dogs were prospectively skin tested and their serum samples were analysed for anti-CCD IgE. An Fc-ε receptor-based serum test for allergen-specific IgE was performed with and without blocking anti-CCD IgE. RESULTS: In dogs with negative anti-CCD IgE samples, the agreement between the results of the serum test and the IDT was substantial (κ = 0.71). Dogs with positive anti-CCD IgE samples (38.7%) showed no agreement between serum and skin testing (κ = -0.35), blocking anti-CCD IgE in those samples resulted in a fair agreement (κ = 0.43). Anti-CCD IgE positive sera had multiple positive results for grass and weed allergens, and blocking decreased them markedly. CONCLUSION AND CLINICAL IMPORTANCE: Intradermal testing agreed best with serum testing in dogs with no detectable anti-CCD IgE. Sera containing anti-CCD IgE had no agreement with IDT. Test agreement was improved by blocking the anti-CCD IgE. Apparent serum test polysensitization to plant allergens was associated with anti-CCD IgE.

Intradermal reactivity to two concentrations of pollen extracts in atopic dogs.

BACKGROUND: Intradermal test (IDT) is used widely for determination of allergens to include in allergen-specific immunotherapy (AIT). The optimal concentration of allergen solutions used for testing has not been established in atopic dogs. Inadequate concentrations could lead to falsely negative test results and lack of inclusion of important allergens in AIT. HYPOTHESIS/OBJECTIVES: To compare IDT reactivity to two concentrations of five pollen extracts and determine the effect on ASIT prescription. ANIMALS: Atopic dogs (n = 67) had IDT results including all of the allergens of interest. METHODS AND MATERIALS: Medical records from a veterinary teaching hospital were reviewed for all atopic dogs undergoing IDT over a three year period. In addition to the hospital's standard IDT concentration of 1,000 PNU/mL for pollen allergens, five pollen allergens of higher concentration (3,000-8,000 PNU/mL) had been added at the beginning of that period. The IDT scores for the standard test concentration of each of the five allergens were compared to the scores for the higher concentration. RESULTS: Positive reactions occurred much more commonly to the higher test concentration for each of the paired allergens (P < 0.05, chi-square). The AIT formulation was different in 58% of the dogs from what it would have been without the higher concentration allergens. CONCLUSIONS AND CLINICAL IMPORTANCE: The current standard IDT concentration of 1,000 PNU/mL for pollen allergens is likely too low, possibly resulting in inaccurate AIT formulations. This might explain treatment failures and the incorrect diagnosis of atopic-like dermatitis. Further work is needed to establish optimal allergen test concentrations.

Longitudinal evaluation of immunological responses to allergen-specific immunotherapy in horses with IgE associated dermatological disease, a pilot study.

BACKGROUND: The long-term effects of allergen specific immunotherapy (ASIT) on concentrations of circulating immunoglobulin E (IgE) and immunoglobulin G (IgG) in horses have not been reported. OBJECTIVES: To document changes in clinical severity of horses with atopic dermatitis (AD) and to monitor allergen-specific IgE and IgG concentrations during a two-year course of ASIT. ANIMALS: Nineteen client-owned horses with a conditional diagnosis of AD. METHODS AND MATERIALS: Three ASIT groups were randomly assigned based upon results obtained by either intradermal testing (IDT) for regional allergens (n = 7); enzyme-linked immunosorbent assay (ELISA) for specific IgE (n = 6); or a composite of results from both tests (n = 6). Serum concentrations of IgE and IgG specific for allergens included in ASIT were measured at time zero and at four-month intervals. A visual analog scale (VAS) was used to record severity of clinical signs at times zero, 12 and 24 months. RESULTS: Positive correlations were documented between IgE and both immediate and delayed IDT results (P < 0.00001), and between immediate IDT and IgG results (P = 0.003). Specific IgE in sera decreased significantly (P < 0.05) for allergens that were included in ASIT, whereas IgG increased. Across all horses, the mean VAS score decreased by 1.2 units [95% CI: 1.28, 1.14; (P < 0.0001)] during each 12-month period of ASIT therapy. Improvement in clinical signs was noted in 76.5% of the horses following 12 months of ASIT and in 82% after 24 months on ASIT. CONCLUSIONS AND CLINICAL IMPORTANCE: In this pilot study, ASIT in horses with AD provided significant clinical benefit associated with a concomitant reduction of allergen-specific IgE and elevation of IgG.

An evaluation of veterinary allergen extract content and resultant canine intradermal threshold concentrations.

BACKGROUND: Limited information is available for dogs on threshold concentrations (TCs), and the protein composition of common allergenic extracts produced by different manufacturers. HYPOTHESIS/OBJECTIVES: To characterize the protein heterogeneity of tree, grass, weed and mite allergens from different lots of allergenic extracts, and to determine intradermal TCs for healthy dogs using extracts from two manufacturers. ANIMALS: Twenty five privately owned, clinically healthy dogs and ten purpose-bred beagle dogs. METHODS AND MATERIALS: Protein concentration and heterogeneity of 11 allergens from two manufacturers were evaluated using a Bradford-style assay and SDS-PAGE. Intradermal testing was performed with 11 allergens from each company at four dilutions. Immediate reactions were subjectively scored (0 to 4+), and objectively measured (mm) and their percentage concordance evaluated. Model-based TCs were determined by fitting positive reactions (≥2+) at 15 min to generalized estimating equations. RESULTS: Allergen extract protein quantity and composition varied within and between manufacturers despite sharing the same PNU/mL values. Model-based TCs of one weed, five trees, two grasses and a house dust mite were determined for extracts from Manufacturer 1 (M1), and for extracts of three weeds, three trees and two grasses from Manufacturer 2 (M2). Receiver operating characteristic curve analyses determined a percentage concordance of the objective and subjective measurements of 77.3% for M1 and 75% for M2 allergens. CONCLUSIONS AND CLINICAL IMPORTANCE: Veterinary allergen extracts labelled as the same species and PNU/mL are not standardized; they show heterogeneity in composition and potency within and between manufacturers. Variability in extract content may require adjustment of intradermal testing concentrations.