Introdução: Esofagite eosinofílica (EoE) é uma desordem clínico-patológica, caracterizada por sintomas de disfunção esofágica e alterações histopatológicas com inflamação composta principalmente por eosinófilos, sendo necessário, pelo último consenso, 15 ou mais eosinófilos/campo microscópico de grande aumento (cmga). Contudo, esse achado histopatológico geralmente está acompanhado de outras alterações morfológicas na mucosa esofágica que fazem parte do quadro de resposta inflamatória e que têm sido cada vez mais investigadas. Objetivos: Descrever achados histopatológicos em biópsias de pacientes pediátricos e adolescentes com EoE e compará-las aos de pacientes com quadro clínico de epigastralgia. Material e métodos: Foram analisadas biópsias esofágicas, sendo dezessete com diagnóstico de EoE e dezessete com epigastralgia. Analisaram-se aspectos histopatológicos e imuno-histoquímicos, como número máximo de eosinófilos, alongamento das papilas, hiperplasia de células da camada basal, espaços intercelulares, microabscessos e expressão de CD1a. Resultados: Entre os achados histopatológicos, alongamento das papilas e hiperplasia da camada basal foram observados em todos os participantes com EoE e em nenhuma amostra do grupo epigastralgia. Aumento do espaço intercelular foi encontrado em todos os pacientes com EoE e em 29,41% dos pacientes com epigastralgia. Conclusões: A quantidade de eosinófilos pode não mostrar por si só a complexidade da EoE. Estudos futuros devem ser realizados tentando definir se algum achado morfológico pode ajudar no diagnóstico diferencial entre EoE e eosinofilia esofágica responsiva ao inibidor de bomba de prótons e se poderiam ser utilizados para acompanhamento da eficácia do tratamento da EoE. / Introduction: Eosinophilic esophagitis (EoE) is a clinical-pathological disorder, characterized by symptoms related to esophageal dysfunction and histopathological alterations with inflammatory reactions primarily composed of eosinophils, being necessary, by the last consensus, 15 or more eosinófilos / high-power field (hpf). However, this histopathological finding is usually accompanied by other morphological changes in the esophageal mucosa that are part of an inflammatory response that has been increasingly investigated. Objective: To describe the histopathological findings from biopsies of pediatric and adolescent patients with EoE and to compare them with those from patients with clinical symptoms of epigastralgia. Material and methods: The results of esophageal cultures from biopsies were analyzed, seventeen with EoE diagnosis and seventeen with epigastralgia. The histopathological and immunohistochemical aspects, such as maximum number of eosinophils, papillary elongation, basal cell hyperplasia, dilatation of intercellular spaces, microabscesses, and CD1a expression were analyzed. Results: Among the histopathological findings, papillary elongation and basal cell layer hyperplasia were observed in all participants with EoE and in any of the sample of the epigastralgia group. Dilated intercellular space was found in all patients with EoE and in 29.41% of patients with epigastralgia. Conclusions: The amount of eosinophils may not by itself show the complexity of EoE. Future studies should be carried out in order to determine if any morphological findings may help in the differential diagnosis between EoE and proton-pump inhibitor-responsive esophageal eosinophilia, and whether they could be used to monitor the effectiveness of the EoE treatment. / Dissertação (Mestrado)

No description available.

No description available.

The esophageal epithelium is a stratified squamous tissue. Maintenance of the esophageal epithelial proliferation-differentiation gradient is critical as esophageal epithelium is the first line barrier to prevent penetration of digestive contents, while abnormal epithelial repair contributes to remodeling and disease development. Autophagy has been demonstrated to play roles in esophageal pathologies both benign and malignant, however, the role of autophagy in normal esophageal biology remains elusive. We hypothesize that autophagy may contribute to the maintenance of the proliferation/differentiation gradient under homeostasis in the esophageal epithelium. To investigate the role of autophagy in esophageal epithelium under homeostatic conditions and in response to the carcinogen 4-nitroquinoline 1-oxide (4NQO), we utilize a novel mouse model with tamoxifen-inducible, squamous epithelial-specific Atg7 (autophagy-related 7) conditional knockout. We report that genetic autophagy inhibition in squamous epithelium under homeostatic conditions resulted in enhanced proliferation of esophageal basal cells and increased thickness of epithelium, whether challenging these mice with 4NQO-induced dramatic weight loss that further displayed perturbed epithelial tissue architecture evaluated by histological and biochemical analyses. To characterize cells with high and low levels of autophagic vesicle (AV) content functionally and molecularly, we sorted esophageal basal cells based upon fluorescence of the AV-identifying dye Cyto-ID. We then used transmission electron microscopy validate increased AVs in esophageal basal cells with high AV level (Cyto-IDHigh) as compared to their counterparts with low AV level (Cyto-IDLow). Cyto-IDHigh esophageal basal cells displayed limited organoid formation capability upon initial plating but passaged more efficiently as compared to Cyto-IDLow esophageal basal cells. By RNA-Seq we identified increased autophagy in Cyto-IDHigh esophageal basal cells along with decreased cell cycle progression, the latter of which was confirmed by cell cycle analysis. scRNA-Seq of 3D organoids generated by Cyto-IDLow and Cyto-IDHigh cells identified expansion of 3 cell populations, enrichment of G2/M-associated genes in the Cyto-IDHigh group. Ki67 expression was also increased in organoids generated by Cyto-IDHigh cells, including in cells located beyond the outermost basal cell layer. Taken together, these studies provide evidence that ATG7 contributes to homeostasis of esophageal epithelium, in which esophageal basal cells with high level of AVs exhibit limited proliferation. When esophageal basal cells with high AV level are cultured in 3D organoid assays, they exhibit increased self-renewal and enhanced proliferative capacity extending beyond the outermost basal cell layer.Maintenance of the esophageal proliferation-differentiation gradient is a key to support proper functioning of the esophagus and its dysregulation can lead to the development of esophageal pathologies. Published studies provide evidence of epithelial-fibroblast crosstalk in the development of subepithelial fibrosis, a typical type of tissue remodeling found in patients with eosinophilic esophagitis (EoE). The current paradigm presents EoE as a progressive fibrostenotic disease of the esophagus in which aged patients develop fibrosis as a function of disease chronicity. We hypothesize that age of esophageal epithelium may affect EoE presentation. To directly test the impact of age upon EoE disease presentation, we treated young and aged mice with MC903/Ovalbumin to induce EoE inflammation for the same time period. We found increased thickness of lamina propria in aged mice with EoE as compared to their young counterparts, suggesting that age-associated alterations in esophageal biology contribute to EoE-associated fibrosis. To evaluate the impact of esophageal epithelial cell age on EoE-associated fibrosis, we generated primary esophageal epithelial cell lines from young and aged mice and determined the effects of these cells on fibroblast contractility in collagen plug contraction assays in vitro. These studies revealed that esophageal epithelial cells from aged mice limited fibroblast contractility less efficiently than those from their young counterparts. To identify potential signaling pathways through which aged esophageal epithelial cells may stimulate fibrotic remodeling, we conducted cytokine array analysis. We found 6 cytokines/soluble factors that have not previously been linked to EoE but may contribute to fibrotic remodeling. Taken together, this dissertation provides (1) foundation for further studies evaluating the role of autophagy and mechanisms of its regulation in the context of normal homeostasis and carcinogen-induced stress as well as (2) identification of age-associated factors that may contribute to fibrotic remodeling that may aid in the design of strategies toward early detection, prevention, and therapy of fibrostenotic EoE. / Biomedical Sciences

Introduction: Eosinophilic Esophagitis (EoE) is a rare allergic inflammatory disease affecting approximately 1-4 in every 10,000 individuals in the United States. With the dramatic increase in prevalence of EoE in recent years and the increasing use of the internet as a source of health care information, we sought to evaluate the educational quality of EoE videos on YouTube. Methods: We performed a YouTube search using the keyword “eosinophilic esophagitis” from September 8-27, 2016. All available videos were included and analyzed for video characteristics, source, and content. Source was further classified as health-care provider, alternative-medicine provider, patient and/or patient's parents, company, media, or professional society. A scoring system was created based on current guidelines to evaluate the quality of information (-10 to +30 points).Negative points were assigned for misleading information. Six blinded reviewers scored each video independently. Results: Two hundred and nine videos were analyzed, with a median of 507 views, 1 like, 0 dislikes, and 0 comments. More video presenters were male (50.9%), and the most commonly depicted race was Caucasian (73.6%). The most common type of video source was professional society (39.7%), and the least represented video source was company and media (8.6%). Among the four video sources, the mean scores showed a statistically significant difference from each other (pConclusion: Youtube videos on EoE were shown to be a poor source of valid health care information. Videos by health care providers were a better source of information compared to other sources. This study reiterates the need for higher quality educational videos on EoE by the medical community.

Master of Veterinary Clinical Studies / Summary Canine Neural Angiostrongyliasis (CNA) is caused by the obligatory neural migration of Angiostrongylus cantonensis larvae in dogs. Characteristically, cases are juvenile dogs with progressive CNS dysfunction characterised by hyperaesthesia and often associated with eosinophilic pleocytosis of the CSF. In Australia, most cases occur between March and June. The rat lungworm, A cantonensis was first described by Chen in 1935 in Canton, China. While initially called Pulmonema cantonensis the parasite was later reclassified as A cantonensis. A disease diagnosed as eosinophilic meningoencephalitis was first described in 1944 in Taiwan. The same disease was reported in 1948 in the East Caroline Islands but it was not until 1961 that A cantonensis was confirmed as the aetiological agent when a patient in a Hawaiian mental institution, who had died of eosinophilic meningoencephalitis, had A cantonensis larvae recovered from the brain and spinal cord. The first reports of animals infected with A cantonensis were made by Mason in 1976 when he described a syndrome occurring in puppies in the Brisbane area, characterised by urinary incontinence, hind limb paresis and hyperaesthesia, often associated with eosinophilic pleocytosis of the CSF. Reports of infection in other species followed including macropods, bats, horses, primates and birds. Twenty-two cases of suspected CNA were collected prospectively to compare with those previously described, including 37 cases published by Mason in 1983, and to examine the accuracy of an ELISA used to diagnose human neural angiostrongyliasis in Australia. Samples were collected from two control populations in an attempt to validate the ELISA results. In the prospective series of cases, there was a significantly older subpopulation of dogs in addition to “classical” young dogs, suggesting that this syndrome can occur at any age and should be considered a differential in any dog with progressive neurological disease. The mortality rate in the prospective group was lower than in the published group, which is a reflection of the severity of the disease in younger animals as is the case with human patients. Definitive diagnosis of neural angiostrongyliasis in human patients has been achieved by identifying A cantonensis larvae within the CSF or aqueous humour. In dogs, the only definitive way to diagnose CNA has been via necropsy. While many cases of CNA are characteristic and presumptive diagnosis can be made based on typical history, signalment, clinical signs, CSF analysis and response to glucocorticoids, there appear to be an increasing number of cases occurring in older dogs, that displaying focal, atypical clinical signs or that develop permanent sequelae. Serology has been a useful tool in diagnosing neural angiostrongyliasis in humans. In its current form the ELISA is not sensitive or specific enough to allow a definitive diagnosis of CNA to be made using serum but is useful when applied to CSF specimens. Further refinement of the antigen or using monoclonal rather than polyclonal antibodies may improve the accuracy of the serology. Alternatively, methods such as Western Blot, Immuno-PCR or dot-blot ELISA, which have been successfully used to diagnoses angiostrongyliasis in humans, may be worthy of investigation The major differential diagnosis for CNA is neosporosis. Other differential diagnoses include idiopathic eosinophilic meningoencephalitis, parasitic infections including Toxoplasma gondii, Taenia solium, Gnathostoma spinigerum, visceral larval migrans (Toxocara canis) and schistosomiasis, fungal, bacterial, viral and rickettsial infections as well as neoplasia, trauma, drug reactions and toxicities. Treatment of CNA has been limited to glucocorticoids, however there may be adjunct therapies including anthelmintices, cyclosporine, and matrix metalloproteinase inhibitors. In Mason’s series of cases the use of anthelmintics significantly worsened the clinical outcome for patients. It does not appear, however, that the use of these agents in species other than the dog exacerbates clinical signs. Acquired immunity is short lived in rats and mice, which would suggest the same is true in dogs. Routine heartworm and intestinal parasite prophylaxis appears to have no influence on the occurrence of CNA.

Master of Veterinary Clinical Studies / Summary Canine Neural Angiostrongyliasis (CNA) is caused by the obligatory neural migration of Angiostrongylus cantonensis larvae in dogs. Characteristically, cases are juvenile dogs with progressive CNS dysfunction characterised by hyperaesthesia and often associated with eosinophilic pleocytosis of the CSF. In Australia, most cases occur between March and June. The rat lungworm, A cantonensis was first described by Chen in 1935 in Canton, China. While initially called Pulmonema cantonensis the parasite was later reclassified as A cantonensis. A disease diagnosed as eosinophilic meningoencephalitis was first described in 1944 in Taiwan. The same disease was reported in 1948 in the East Caroline Islands but it was not until 1961 that A cantonensis was confirmed as the aetiological agent when a patient in a Hawaiian mental institution, who had died of eosinophilic meningoencephalitis, had A cantonensis larvae recovered from the brain and spinal cord. The first reports of animals infected with A cantonensis were made by Mason in 1976 when he described a syndrome occurring in puppies in the Brisbane area, characterised by urinary incontinence, hind limb paresis and hyperaesthesia, often associated with eosinophilic pleocytosis of the CSF. Reports of infection in other species followed including macropods, bats, horses, primates and birds. Twenty-two cases of suspected CNA were collected prospectively to compare with those previously described, including 37 cases published by Mason in 1983, and to examine the accuracy of an ELISA used to diagnose human neural angiostrongyliasis in Australia. Samples were collected from two control populations in an attempt to validate the ELISA results. In the prospective series of cases, there was a significantly older subpopulation of dogs in addition to “classical” young dogs, suggesting that this syndrome can occur at any age and should be considered a differential in any dog with progressive neurological disease. The mortality rate in the prospective group was lower than in the published group, which is a reflection of the severity of the disease in younger animals as is the case with human patients. Definitive diagnosis of neural angiostrongyliasis in human patients has been achieved by identifying A cantonensis larvae within the CSF or aqueous humour. In dogs, the only definitive way to diagnose CNA has been via necropsy. While many cases of CNA are characteristic and presumptive diagnosis can be made based on typical history, signalment, clinical signs, CSF analysis and response to glucocorticoids, there appear to be an increasing number of cases occurring in older dogs, that displaying focal, atypical clinical signs or that develop permanent sequelae. Serology has been a useful tool in diagnosing neural angiostrongyliasis in humans. In its current form the ELISA is not sensitive or specific enough to allow a definitive diagnosis of CNA to be made using serum but is useful when applied to CSF specimens. Further refinement of the antigen or using monoclonal rather than polyclonal antibodies may improve the accuracy of the serology. Alternatively, methods such as Western Blot, Immuno-PCR or dot-blot ELISA, which have been successfully used to diagnoses angiostrongyliasis in humans, may be worthy of investigation The major differential diagnosis for CNA is neosporosis. Other differential diagnoses include idiopathic eosinophilic meningoencephalitis, parasitic infections including Toxoplasma gondii, Taenia solium, Gnathostoma spinigerum, visceral larval migrans (Toxocara canis) and schistosomiasis, fungal, bacterial, viral and rickettsial infections as well as neoplasia, trauma, drug reactions and toxicities. Treatment of CNA has been limited to glucocorticoids, however there may be adjunct therapies including anthelmintices, cyclosporine, and matrix metalloproteinase inhibitors. In Mason’s series of cases the use of anthelmintics significantly worsened the clinical outcome for patients. It does not appear, however, that the use of these agents in species other than the dog exacerbates clinical signs. Acquired immunity is short lived in rats and mice, which would suggest the same is true in dogs. Routine heartworm and intestinal parasite prophylaxis appears to have no influence on the occurrence of CNA.

Les leucémies chroniques à éosinophiles sans autre spécification (CEL,NOS) sont des néoplasmes myéloprolifératifs rares caractérisés par une hyperéosinophilie (HE) clonale. Avec 12 cas décrits, la translocation t(5;12)(q31;p13), différente de la translocation t(5;12)(q32;p13) ETV6-PDGFRB classique, semble être récurrente de cette entité. Peu étudiée, sa leucémogenèse reste non élucidée.L’objectif de ce travail était la caractérisation génomique et transcriptomique de ce remaniement afin d’en comprendre la physiopathologie.L’étude FISH sur cellules triées réalisée confirmait l’HE clonale, et indiquait un avantage sélectif semblant limité aux polynucléaires éosinophiles (PNE), puisque d’autres cellules, également porteuses de la translocation, ne proliféraient pas.Un transcrit de fusion ETV6-FNIP1, jamais décrit, différent des transcrits ETV6-ACSL6 habituellement observés, a été retrouvé dans le cas d’étude. La non récurrence d’un transcrit fonctionnel commun entre les cas était en défaveur de leur implication dans la leucémogenèse par l’apport d’une nouvelle fonction.ETV6 et ACSL6 étaient constamment impactés par le réarrangement, soit par formation d’un transcrit, soit par délétion comme dans le cas d’étude. Leur diminution d’expression, en l’absence de second événement, témoignait de l’haploinsuffisance de ces gènes suppresseurs de tumeurs.Par l’étude d’une cohorte de 39 patients avec HE, nous avons montré une dérégulation spécifique d’IL-3 dans la translocation t(5;12)(q31;p13), sans atteinte d’IL-5 ni de CSF2 (GM-CSF), cytokines impliquées dans l’éosinopoïèse. Des séquences conservées situées dans l’intron 2 d’ETV6 et en aval de l’exon 11 d’ACSL6 pourraient être responsables de cette dérégulation.Sans autre anomalie spécifique retrouvée, la translocation t(5;12)(q31;p13) constitue l’évènement oncogénique principal de ces cas. Parmi les mécanismes étudiés, plusieurs, sinon tous, pourraient être nécessaires au développement de la maladie. / Chronic eosinophilic leukemias not otherwise specified (CEL, NOS) is a rare myeloproliferative neoplasm characterized by clonal eosinopoiesis. In this setting, we studied a patient with a t(5;12)(q31;p13) which differs from the usual t(5;12)(q32;p13) ETV6-PDGFRB translocation. In this rare translocation (11 similar examples so far described in the litterature), mechanisms driving leukemogenesis still need to be investigated.The aim of this study was the genomic and transcriptomic characterization of this translocation in order to understand its pathophysiology.Triaged FISH study confirmed clonal HE, and suggested a specific advantage limited to eosinophils, since other nonproliferative cells also carried the translocation.A novel ETV6-FNIP1 fusion transcript hitherto never described was found. This transcript was different from the usual out-of-frame ETV6-ACSL6 transcripts, and no common functional transcript was observed among the published cases. The implication of these transcripts seems unlikely.ETV6 and ACSL6 are constantly impacted by rearrangement, either by a fusion transcript or by deletion as in the case study. Their underexpression, in the absence of a second hit, support the haploinsufficiency of these tumor suppressor genes.By studying a cohort of 39 patients with HE, we show a deregulation of IL-3 in the t(5;12)(q31;p13) translocation, without deregulation of IL-5 or CSF2 (GM-CSF), cytokines involved in eosinopoiesis. Conserved sequences in ETV6 intron 2 and downstream of ACSL6 exon 11 may be responsible for this deregulation.The t(5;12)(q31;p13) constitues the main oncogenic driver. From the mechanisms studied, many, if not all, may be associated for the development of the disease.

Esofagite Eosinofílica é uma doença inflamatória crônica restrita ao esôfago e imune mediada por antígenos. Sua prevalência descrita varia desde 0,4%, numa população geral, até 15% em pacientes com sintomas de disfagia. Já se conhece sua associação com doenças atópicas, anafilaxia e alergia alimentar, sendo o leite de vaca um dos principais alimentos envolvidos. Existem relatos recentes de casos em que pacientes foram diagnosticados com esofagite eosinofílica após serem submetidos à imunoterapia oral com o alimento causador de sua alergia alimentar mediada por IgE. Porém, em nenhum destes casos foi avaliado previamente se os mesmos pacientes já não apresentavam eosinofilia esofágica latente e/ou sintomas subjetivos sugestivos da doença. Considerando que, atualmente, um dos tratamentos mais promissores para alergia alimentar é a imunoterapia oral, justificou-se a necessidade de entender se esofagite eosinofílica seria de fato uma complicação do tratamento, ou se seria uma condição pré ou coexistente. Portanto, o objetivo deste trabalho foi avaliar a frequência de eosinofilia esofágica em pacientes com anafilaxia à proteína do leite de vaca. Foram analisados 89 pacientes matriculados no ambulatório de alergia alimentar do HC-FMUSP, com mediana de idade de 8 anos e que apresentavam anafilaxia ao leite de vaca. Todos foram submetidos à endoscopia digestiva alta com biópsias de esôfago, estomago e duodeno. Dados demográficos, comorbidades atópicas, uso de medicações e sintomas gastrointestinais foram analisados e comparados. A frequência de eosinofilia esofágica foi de 38,2% (34 de 89 pacientes). Em 15 dos 34 pacientes com eosinofilia esofágica, foi completada a investigação para esofagite eosinofílica com uso de inibidor de bomba de prótons em dose plena por 8 semanas antes de uma segunda endoscopia. Identificou-se, portanto, cinco pacientes (7,1%) com eosinofilia esofágica responsiva a inibidor de bomba de prótons e 10 pacientes com esofagite eosinofílica (14,2%). No grupo total de pacientes com eosinofilia esofágica (n=34) encontrou-se 29,4% de pacientes com quadro clínico gastrointestinal ausente; 23,5% oligossintomáticos, e apenas 47% com sintomas sugestivos de disfunção esofágica e, destes últimos, nem todos apresentavam sintomas esofágicos persistentes. Pode-se concluir que a frequência de esofagite eosinofílica descrita no grupo estudado foi significativamente superior à estimada na população geral e uma das mais altas descritas em grupos de pacientes com fatores de risco específicos. Também foi observada uma grande parcela de pacientes com eosinofilia esofágica, sendo muitos assintomáticos ou oligossintomáticos, surgindo o questionamento se esta não seria uma doença latente, de início precoce, insidioso e não relacionada diretamente como complicação de tratamentos atuais / Eosinophilic esophagitis is a chronic inflammatory disease, which occurs in the esophagus and is immune mediated by antigens. Its observed prevalence varies between 0.4% in the general population to 15% in patients with dysphagia. Its association with atopic diseases, anaphylaxis and food allergy has already been recognized. Cow\'s milk is one of the main food sources involved. There are recent reports of cases in which patients were diagnosed with eosinophilic esophagitis after being submitted to oral immunotherapy with the food that causes the IgE mediated allergy. However, in none of these cases was it previously determined if the same patients did not already present latent esophageal eosinophilia and/or subjective symptoms suggestive of the disease. Considering that, currently, one of the most promising treatment for food allergy is oral immunotherapy, the need to understand if eosinophilic esophagitis could be a treatment complication, or if it is a coexistent or preexistent condition, is justified. Therefore, the objective of this study was to evaluate esophageal eosinophilia frequency in patients with anaphylaxis to cow\'s milk protein. We analyzed eighty-nine patients registered in the Food Allergy Unit of the HCFMUSP, with a median age of 8 years, who presented cow\'s milk anaphylaxis. All of them were submitted to digestive endoscopy as well as esophagus, stomach, and duodenum biopsies. We also analyzed and compared demographic data, atopic comorbidities, use of medication, and gastrointestinal symptoms. The frequency of esophageal eosinophilia was 38.2% (34 of 89 patients). In 15 of the 34 patients with esophageal eosinophilia, full investigation for the disease was carried out using a proton pump inhibitor at full dose for eight weeks prior to a second endoscopy. From this, five patients (7.1%) had the proton pump inhibitor-responsive esophageal eosinophilia phenotype, and ten patients were diagnosed with eosinophilic esophagitis (14.2%). In the whole group of patients with esophageal eosinophilia (n = 34), it was found 29.4% of patients with an absent gastrointestinal clinical condition, 23.5% were oligosymptomatic, and only 47% had symptoms suggestive of esophagic dysfunction. Of these, not all presented persistent esophagic symptoms. It is possible to conclude that the frequency of eosinophilic esophagitis observed in this group was significantly higher than the estimated for the general population, and one of the highest observed in groups of patients with specific risk factors. A large portion of patients with esophageal eosinophilia were oligosymptomatic or asymptomatic, raising the question if this would not in fact be a latent disease, with a precocious beginning, insidious and not directly related to current treatments complications

Objetivo: Avaliar o teste de contato atópico (TCA) em pacientes com alergia ao leite de vaca (APLV) IgE mediada - grupo 1 e naqueles com doenças eosinofílicas do trato digestório (DETD) - grupo 2, comparando os extratos de leite de vaca (LV) a 20% com o leite in natura, o tempo ideal de oclusão do teste e o valor preditivo positivo do TCA na identificação do leite como desencadeante no grupo 2, avaliada pela melhora clinica e endoscópica após dieta de restrição. Métodos: Estudo de corte transversal, com avaliação de 45 pacientes e 9 controles. O grupo 1 (n=15) com APLV IgE mediada foram diagnosticados pelo teste de provocação e prick teste positivo para LV e o grupo 2 (n=30) pela biópsia mostrando esofagite eosinofílica (15 eosinófilos/cga) ou enterocolite eosinofílica (>20 eosinófilos/cga), prick teste positivo para LV (n=15) e sintomas desencadeados pelo leite. O grupo 3 (n=9) incluiu pacientes com exclusão do diagnóstico de APLV. Utilizou-se câmaras de 12mm e LV in natura e LV a 20% como extratos ( IPI ASAC, Espanha). Os tempos de leitura foram de 24, 48 e 72 horas e considerou-se como TCA positivo, a presença de hiperemia com infiltração e formação de pápulas ou vesículas. Para avaliação do valor preditivo positivo do TCA, considerou-se pacientes com DETD com sintomas associados ao leite, sem melhora com tratamento adequado, IgE específica ao LV e melhora clínica e histológica com a instituição da dieta de restrição. Resultados: Considerando ambos os extratos, houve semelhança quanto à frequência de positividade do TCA nos três tempos de leitura em ambas situações clínicas. Com relação à concordância entre os tempos de leitura do TCA com ambos extratos, observou-se diferença estatisticamente significante entre o tempo de 24 hs com aqueles de 48 e 72hs (p=0,031 em ambas comparações), o mesmo não ocorrendo entre o tempo de 48 e 72hs tanto na APLV como nas DETD. Isoladamente, o LV a 20% mostrou comportamento semelhante em ambas as doenças, com diferença entre o tempo de 24 e aqueles de 48 (p=0,031 / 0,000) e 72hs (p=0,031/ 0,002) respectivamente na APLV e DETD. O extrato de leite in natura nos pacientes com APLV não mostrou diferença estatisticamente significante entre os tempos avaliados, enquanto nos pacientes com DETD observou-se diferença entre 24 hs e os tempos de 48hs (p=0,003) e 72hs (p=0,003). A restrição dietética do leite naqueles pacientes com DETD e TCA positivo foi associada à melhora clínica em 80% dos pacientes e associação com melhora histológica em 65% destes. Conclusões: O TCA utilizando tanto LV in natura como extrato LV a 20%, com leitura após 48 ou 72hs da sua aplicação mostrou-se útil na identificação de pacientes com DETD desencadeada pelo LV. A instituição de dieta restrita neste alimento contribuiu para a melhora dos sintomas e para a redução do número de eosinófilos na biópsia de controle / Objective: To evaluate the atopic patch test (APT) in IgE mediated cow\'s milk allergic patients (CMA) - Group 1 and those with gastrointestinal eosinophilic diseases (GED) - Group 2, comparing extracts of cow\'s milk (CM) 20% protein concentration and fresh milk, the optimal time reading and the positive predictive value of APT in the identification of milk as a trigger food in the group 2, as assessed by clinical and endoscopic improvement after dietary restriction. Methods: Cross-sectional study with evaluation of 45 patients and 9 controls. The group 1 (n = 15) with IgE-mediated CMA was diagnosed by provocation test and positive skin prick test for CM in all patients and group 2 (n = 30) by biopsy showing eosinophilic esophagitis ( 15 eosinophils / hpf) or eosinophilic enterocolitis (> 20 eosinophils / hpf ), prick test positive for CM (n = 15) and symptoms triggered by milk. Group 3 (n = 9) included patients which CMA was excluded. It was used 12mm a plastic chamber of inert material, and as extracts the fresh milk and CM at 20% (IPI ASAC, Spain). The reading times were 24, 48 and 72 hours and was considered as APT positive, the presence of hyperemia with infiltration and papules or vesicles. To evaluate the positive predictive value of the APT, it was considered GED patients with symptoms associated to milk, no response to treatment, specific IgE to CM and clinical and histological improvement after the restricted diet institution. Results: Considering both extract, there was similarity in the frequency of positive APT evaluating all the reading times in both clinical situations. Regarding the agreement between the reading times with both extracts, there was a statistically significant difference between the time of 24 hours with those of 48 and 72 hours (p = 0.031 for both comparisons). This fact was not observed between the time of 48 and 72 hours in both diseases. The CM 20% extract showed a similar pattern in both diseases, with difference between the reading time of 24 with the 48 hours (p = 0.031/0.000) and 72 hours (p = 0.031/ 0.002) respectively in both diseases. The fresh milk extract in CMA patients showed no statistically significant difference between the reading times evaluated, while in GED patients it was observed difference between 24 hours with the time of 48 hours (p = 0.003) and 72 hours (p = 0.003). The milk restricted diet for GED patients with positive APT was associated to clinical improvement in 80% of patients and in both clinical and histological response in 65% of them. Conclusions: The APT using both fresh CM and CM 20% extract with reading time of 48 or 72 hours showed useful in identifying GED patients triggered by CM. The establishment of milk restricted diet contributed to the improvement of symptoms and to reduce the number of eosinophils in the control biopsy