{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T04:03:50Z","timestamp":1775448230193,"version":"3.50.1"},"reference-count":52,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T00:00:00Z","timestamp":1775174400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Veterinary Sciences"],"abstract":"<jats:p>Canine atopic dermatitis (CAD) is a chronic, pruritic inflammatory disease that affects up to 15% of the global canine population. Its etiopathogenesis is multifactorial, involving genetic, immunological, environmental, and dietary factors. It is characterized by pruritus, erythema, alopecia, and secondary lesions, predominantly affecting the abdomen, extremities, and ears. This retrospective cross-sectional descriptive study analyzed 735 medical records of dogs diagnosed with CAD treated at the Veterinary Specialty Center (CEVET) in Quito, Ecuador, between January 2018 and July 2025. Demographic, clinical, housing, diet, and cohabitation data were collected and statistically analyzed using \u03c72 for qualitative variables and the Kruskal\u2013Wallis test for quantitative variables, with post hoc analysis as appropriate. Additionally, pruritus severity was assessed using the Pruritus Visual Analog Scale (pVAS). A composite Clinical Severity and Distribution Score (CSDS) was also developed to classify disease severity. A multivariate logistic regression model was performed to identify factors associated with severe CAD. The results showed a predominance of CAD in adult dogs (84.2%) and purebred dogs (74.97%), with a slight majority being males (52.38%). Pruritus was the most frequent initial symptom (80.27%), with most cases presenting moderate-to-severe pruritus (pVAS 7\u201310). The most affected areas were the abdomen (24.49%) and forelimbs (17.68%). The geographical distribution showed a predominance of urban areas (88.84%) and cold climates (86.39%). Based on the CSDS, 53.2% of cases were classified as severe, 44.4% as moderate, and 2.4% as mild. Multivariate analysis revealed that grass exposure was significantly associated with severe CAD (OR = 1.78; 95% CI: 1.22\u20132.60; p = 0.003), while urban environment showed a non-significant trend toward increased severity (OR = 1.41; p = 0.071). Significant associations were identified involving sex and body weight, age and affected area, and temporal variations in the severity of pruritus, age group, and distribution of lesions. Among breeds, French Bulldogs, Standard Schnauzers, and Shih Tzus had the highest prevalence of CAD. These findings provide the first systematic epidemiological and clinical characterization of CAD in Ecuador, highlighting the role of environmental factors in disease severity and supporting the use of composite clinical scoring approaches in retrospective studies, thereby contributing to understanding of the disease and serving as a reference for early diagnosis, clinical management, and the development of preventive strategies.<\/jats:p>","DOI":"10.3390\/vetsci13040351","type":"journal-article","created":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T02:06:21Z","timestamp":1775441181000},"page":"351","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Epidemiological and Clinical Characterization of Atopic Dermatitis in Dogs from Quito, Ecuador: Retrospective Analysis of Cases (2018\u20132025)"],"prefix":"10.3390","volume":"13","author":[{"given":"Ver\u00f3nica","family":"Pareja-Mena","sequence":"first","affiliation":[{"name":"CEVET, Centro de Especialidades Veterinarias, Alemania y Vancouver, Quito EC 170515, Ecuador"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniela","family":"Flor-Dillon","sequence":"additional","affiliation":[{"name":"Facultad de Medicina Veterinaria y Zootecnia, Universidad Central del Ecuador, Jer\u00f3nimo Leyton S\/N y Gatto Sobral, Quito EC 170515, Ecuador"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4444-0054","authenticated-orcid":false,"given":"Byron","family":"Puga-Torres","sequence":"additional","affiliation":[{"name":"Facultad de Medicina Veterinaria y Zootecnia, Universidad Central del Ecuador, Jer\u00f3nimo Leyton S\/N y Gatto Sobral, Quito EC 170515, Ecuador"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5306-0240","authenticated-orcid":false,"given":"Anthony","family":"Loor-Giler","sequence":"additional","affiliation":[{"name":"Laboratorios de Investigaci\u00f3n, Direcci\u00f3n General de Investigaci\u00f3n, Universidad de las Am\u00e9ricas (UDLA), Antigua V\u00eda a Nay\u00f3n S\/N, Quito EC 170124, Ecuador"},{"name":"Facultad de Ciencias Veterinarias, Universidad de Buenos Aires, Av. Chorroar\u00edn 280, Buenos Aires 1427, Argentina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4421-5321","authenticated-orcid":false,"given":"Luis","family":"N\u00fa\u00f1ez","sequence":"additional","affiliation":[{"name":"Facultad de Ciencias de la Salud, Carrera de Medicina Veterinaria, Universidad de Las Am\u00e9ricas, Antigua V\u00eda a Nay\u00f3n S\/N, Quito EC 170124, Ecuador"},{"name":"One Health Research Group, Facultad de Ciencias de la Salud, Universidad de Las Am\u00e9ricas, Quito EC 170124, Ecuador"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"201","DOI":"10.1136\/vr.f1134","article-title":"Canine Atopic Dermatitis\u2014What Have We Learned?","volume":"172","author":"Nuttall","year":"2013","journal-title":"Vet. Rec."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"800","DOI":"10.1067\/mai.2003.1334","article-title":"Heredity, Pet Ownership, and Confounding Control in a Population-Based Birth Cohort","volume":"111","author":"Almqvist","year":"2003","journal-title":"J. Allergy Clin. Immunol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"547","DOI":"10.1111\/vde.12965","article-title":"Advances in Our Understanding of Canine Atopic Dermatitis","volume":"32","author":"Marsella","year":"2021","journal-title":"Vet. Dermatol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"375","DOI":"10.1111\/vde.13300","article-title":"Updated Insights into the Molecular Pathogenesis of Canine Atopic Dermatitis","volume":"36","author":"Banovic","year":"2025","journal-title":"Vet. Dermatol."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Hensel, P., Santoro, D., Favrot, C., Hill, P., and Griffin, C. (2015). Canine Atopic Dermatitis: Detailed Guidelines for Diagnosis and Allergen Identification. BMC Vet. Res., 11.","DOI":"10.1186\/s12917-015-0515-5"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1111\/vde.12196","article-title":"Review: Clinical and Histological Manifestations of Canine Atopic Dermatitis","volume":"26","author":"Bizikova","year":"2015","journal-title":"Vet. Dermatol."},{"key":"ref_7","first-page":"82","article-title":"Atopic Dermatitis in Humans and Dogs","volume":"61","author":"Arcique","year":"2020","journal-title":"Can. Vet. J."},{"key":"ref_8","first-page":"15","article-title":"Canine Atopic Dermatitis: Prevalence, Impact, and Management Strategies","volume":"15","author":"Drechsler","year":"2024","journal-title":"Vet. Med. Res. Rep."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Kurmann, S., Coelho, M.A., David Palma, M., D\u00edaz, L., Castell\u00e1, G., Caba\u00f1es, F.J., Heitman, J., LeibundGut-Landmann, S., and Muchaamba, F. (2025). Fourier Transform Infrared Spectroscopy Enables Rapid Species Discrimination across Malassezia and Strain-Level Typing in M. Pachydermatis. bioRxiv, preprint.","DOI":"10.1101\/2025.09.25.678493"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1111\/vde.13215","article-title":"Update on the Skin Barrier, Cutaneous Microbiome and Host Defence Peptides in Canine Atopic Dermatitis","volume":"35","author":"Santoro","year":"2024","journal-title":"Vet. Dermatol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"165","DOI":"10.1111\/vde.13319","article-title":"Comparative Efficacy and Safety of Ilunocitinib and Oclacitinib for the Control of Pruritus and Associated Skin Lesions in Dogs with Atopic Dermatitis","volume":"36","author":"Forster","year":"2025","journal-title":"Vet. Dermatol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1291","DOI":"10.2460\/javma.254.11.1291","article-title":"Update on Pathogenesis, Diagnosis, and Treatment of Atopic Dermatitis in Dogs","volume":"254","author":"Nuttall","year":"2019","journal-title":"J. Am. Vet. Med. Assoc."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"926","DOI":"10.1002\/vms3.325","article-title":"Canine Atopic Dermatitis: Role of Luteolin as New Natural Treatment","volume":"6","author":"Gugliandolo","year":"2020","journal-title":"Vet. Med. Sci."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1111\/jvp.70022","article-title":"Pharmacokinetics of Ilunocitinib, a New Janus Kinase Inhibitor, in Dogs","volume":"49","author":"Boerngen","year":"2026","journal-title":"J. Vet. Pharmacol. Ther."},{"key":"ref_15","first-page":"1357","article-title":"La Dermatite Atopique Canine","volume":"194","author":"Bensignor","year":"2010","journal-title":"Bull. Acad. Natl. Med."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1111\/vde.70015","article-title":"Preliminary Measurement of Faecal Short-Chain Fatty Acids in Dogs with Canine Atopic Dermatitis","volume":"37","author":"Fernandes","year":"2026","journal-title":"Vet. Dermatol."},{"key":"ref_17","first-page":"85","article-title":"An Update on the Treatment of Canine Atopic Dermatitis","volume":"2012","author":"Marsella","year":"2012","journal-title":"Vet. Med. Res. Rep."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1013","DOI":"10.1111\/jpn.12181","article-title":"Treating Canine Atopic Dermatitis with Unsaturated Fatty Acids: The Role of Mast Cells and Potential Mechanisms of Action","volume":"98","author":"Schumann","year":"2014","journal-title":"J. Anim. Physiol. Anim. Nutr."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Miranda-Cort\u00e9s, A., Mota-Rojas, D., Crosignani-Outeda, N., Casas-Alvarado, A., Mart\u00ednez-Burnes, J., Olmos-Hern\u00e1ndez, A., Mora-Medina, P., Verduzco-Mendoza, A., and Hern\u00e1ndez-\u00c1valos, I. (2023). The Role of Cannabinoids in Pain Modulation in Companion Animals. Front. Vet. Sci., 9.","DOI":"10.3389\/fvets.2022.1050884"},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Kaneki, M., Ohira, C., Takahashi, M., and Fukuyama, T. (2026). Preventive Effect of Bentonite against Pyoderma via Direct Binding Capability of Staphylococci. PLoS ONE, 21.","DOI":"10.1371\/journal.pone.0341148"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1080\/00480169.2025.2543031","article-title":"Staphylococcus Pseudintermedius Isolated from Atopic Dogs with Pyoderma Induces Mast Cell Degranulation","volume":"74","author":"Bell","year":"2026","journal-title":"N. Z. Vet. J."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1111\/jvp.13503","article-title":"Safety of the Selective JAK1 Inhibitor Oclacitinib in Dogs","volume":"48","author":"Nederveld","year":"2025","journal-title":"J. Vet. Pharmacol. Ther."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Wichtowska, A., and Olejnik, M. (2025). Anti-Cytokine Drugs in the Treatment of Canine Atopic Dermatitis. Int. J. Mol. Sci., 26.","DOI":"10.3390\/ijms262210990"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"255","DOI":"10.1111\/all.15946","article-title":"Challenging the Norm: Epicutaneous Immunotherapy for Canine Atopic Dermatitis","volume":"79","author":"Pinto","year":"2024","journal-title":"Allergy"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1111\/vde.12416","article-title":"The Future of Immunotherapy for Canine Atopic Dermatitis: A Review","volume":"28","author":"DeBoer","year":"2017","journal-title":"Vet. Dermatol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"S30","DOI":"10.2460\/javma.22.12.0576","article-title":"A Systematic Review of Allergen Immunotherapy, a Successful Therapy for Canine Atopic Dermatitis and Feline Atopic Skin Syndrome","volume":"261","author":"Mueller","year":"2023","journal-title":"J. Am. Vet. Med. Assoc."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"2055","DOI":"10.1007\/s11259-023-10155-5","article-title":"Canine Amniotic Membrane-Derived Mesenchymal Stem Cells Ameliorate Atopic Dermatitis through Regeneration and Immunomodulation","volume":"47","author":"Kim","year":"2023","journal-title":"Vet. Res. Commun."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1016\/j.cvsm.2018.08.002","article-title":"Therapies in Canine Atopic Dermatitis","volume":"49","author":"Santoro","year":"2019","journal-title":"Vet. Clin. N. Am. Small Anim. Pract."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"2056S","DOI":"10.1093\/jn\/134.8.2056S","article-title":"Canine Atopic Dermatitis: New Targets, New Therapies","volume":"134","author":"DeBoer","year":"2004","journal-title":"J. Nutr."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"588","DOI":"10.1016\/j.jid.2025.12.004","article-title":"Recommendations on in Vitro Models for Canine Atopic Dermatitis","volume":"146","author":"Dubrac","year":"2026","journal-title":"J. Investig. Dermatol."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Olivry, T., DeBoer, D.J., Favrot, C., Jackson, H.A., Mueller, R.S., Nuttall, T., and Pr\u00e9laud, P. (2015). Treatment of Canine Atopic Dermatitis: 2015 Updated Guidelines from the International Committee on Allergic Diseases of Animals (ICADA). BMC Vet. Res., 11.","DOI":"10.1186\/s12917-015-0514-6"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1111\/j.1365-3164.2009.00758.x","article-title":"A Prospective Study on the Clinical Features of Chronic Canine Atopic Dermatitis and Its Diagnosis","volume":"21","author":"Favrot","year":"2010","journal-title":"Vet. Dermatol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"301","DOI":"10.1111\/j.1365-3164.2007.00616.x","article-title":"Development of an Owner-assessed Scale to Measure the Severity of Pruritus in Dogs","volume":"18","author":"Hill","year":"2007","journal-title":"Vet. Dermatol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"78","DOI":"10.1111\/j.1365-3164.2007.00569.x","article-title":"Validation of CADESI-03, a Severity Scale for Clinical Trials Enrolling Dogs with Atopic Dermatitis","volume":"18","author":"Olivry","year":"2007","journal-title":"Vet. Dermatol."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"77","DOI":"10.1111\/vde.12107","article-title":"Validation of the Canine Atopic Dermatitis Extent and Severity Index (CADESI)-4, a Simplified Severity Scale for Assessing Skin Lesions of Atopic Dermatitis in Dogs","volume":"25","author":"Olivry","year":"2014","journal-title":"Vet. Dermatol."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"956","DOI":"10.1002\/sim.8030","article-title":"Sample Size Estimation for Case-crossover Studies","volume":"38","author":"Dharmarajan","year":"2019","journal-title":"Stat. Med."},{"key":"ref_37","unstructured":"IPCC (2006). 2006 IPCC Guidelines for National Greenhouse Gas Inventories, IPCC. Available online: https:\/\/www.ipcc-nggip.iges.or.jp\/public\/gl\/guidelin\/ch4ref1.pdf."},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Harvey, N.D. (2021). How Old Is My Dog? Identification of Rational Age Groupings in Pet Dogs Based Upon Normative Age-Linked Processes. Front. Vet. Sci., 8.","DOI":"10.3389\/fvets.2021.643085"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1111\/vde.13062","article-title":"Validation of the 0\u201310 Verbal Numeric Scale for Assessment of Pruritus Severity in Dogs","volume":"33","author":"Strzok","year":"2022","journal-title":"Vet. Dermatol."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"157","DOI":"10.1016\/j.cvsm.2024.11.001","article-title":"Updates on the Pathogenesis of Canine and Feline Atopic Dermatitis","volume":"55","author":"Gentry","year":"2025","journal-title":"Vet. Clin. N. Am. Small Anim. Pract."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1111\/vde.12198","article-title":"Review: Role of Genetics and the Environment in the Pathogenesis of Canine Atopic Dermatitis","volume":"26","author":"Bizikova","year":"2015","journal-title":"Vet. Dermatol."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1111\/vde.13210","article-title":"Update on the Role of Genetic Factors, Environmental Factors and Allergens in Canine Atopic Dermatitis","volume":"35","author":"Hensel","year":"2024","journal-title":"Vet. Dermatol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1111\/vde.12317","article-title":"Canine Atopic Dermatitis: Breed Risk in Australia and Evidence for a Susceptible Clade","volume":"27","author":"Mazrier","year":"2016","journal-title":"Vet. Dermatol."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1016\/j.tvjl.2015.09.016","article-title":"An Update on the Treatment of Canine Atopic Dermatitis","volume":"207","author":"Saridomichelakis","year":"2016","journal-title":"Vet. J."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1016\/j.cvsm.2024.11.002","article-title":"Updates on the Pathogenesis of Canine Atopic Dermatitis and Feline Atopic Skin Syndrome: Part 2, the Skin Barrier, the Microbiome, and Immune System Dysfunction","volume":"55","author":"Gentry","year":"2025","journal-title":"Vet. Clin. N. Am. Small Anim. Pract."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"105","DOI":"10.1016\/j.cvsm.2018.08.010","article-title":"Diagnosis and Treatment of Canine Acral Lick Dermatitis","volume":"49","author":"Shumaker","year":"2019","journal-title":"Vet. Clin. N. Am. Small Anim. Pract."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1111\/vde.13192","article-title":"Update on the Role of Cytokines and Chemokines in Canine Atopic Dermatitis","volume":"35","author":"Santoro","year":"2024","journal-title":"Vet. Dermatol."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"104","DOI":"10.1111\/vde.12199","article-title":"Review: Innate Immunity, Lipid Metabolism and Nutrition in Canine Atopic Dermatitis","volume":"26","author":"Santoro","year":"2015","journal-title":"Vet. Dermatol."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1016\/j.cvsm.2024.11.003","article-title":"The Role of Diet, Nutrition, and Supplements in Canine Atopic Dermatitis","volume":"55","author":"Eisenschenk","year":"2025","journal-title":"Vet. Clin. N. Am. Small Anim. Pract."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"1068","DOI":"10.1292\/jvms.24-0471","article-title":"Probiotics as an Adjunct in the Treatment of Canine Atopic Dermatitis: A Systematic Review and Meta-Analysis of Studies in Dogs","volume":"87","author":"Pacheco","year":"2025","journal-title":"J. Vet. Med. Sci."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"185","DOI":"10.1002\/vetr.273","article-title":"Canine Atopic Dermatitis: A Common, Chronic and Challenging Dermatosis","volume":"188","author":"Vogelnest","year":"2021","journal-title":"Vet. Rec."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1111\/vde.12740","article-title":"Treatment of Canine Atopic Dermatitis: Time to Revise Our Strategy?","volume":"30","author":"Olivry","year":"2019","journal-title":"Vet. Dermatol."}],"container-title":["Veterinary Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2306-7381\/13\/4\/351\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T02:40:41Z","timestamp":1775443241000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2306-7381\/13\/4\/351"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,4,3]]},"references-count":52,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2026,4]]}},"alternative-id":["vetsci13040351"],"URL":"https:\/\/doi.org\/10.3390\/vetsci13040351","relation":{},"ISSN":["2306-7381"],"issn-type":[{"value":"2306-7381","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,4,3]]}}}