{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,24]],"date-time":"2026-02-24T10:06:00Z","timestamp":1771927560120,"version":"3.50.1"},"reference-count":18,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T00:00:00Z","timestamp":1769472000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Vet. Sci."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>The asynchronous-abdominal curtain sign (A-ACS) is a suggestive ultrasound artifact for pneumothorax in veterinary medicine. However, its specificity has not been fully established.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Case presentation<\/jats:title>\n                    <jats:p>We describe two dyspneic cats displaying a prominent A-ACS despite the absence of findings strongly supportive of pneumothorax. Both cases had severe pulmonary hyperinflation secondary to expiratory flow limitation (feline lower airway disease and suspected anaphylaxis). Sonographic assessment revealed A-ACS and reduced diaphragmatic excursion. Medical management targeting bronchoconstriction and inflammation resulted in complete resolution of respiratory signs, normalization of the abdominal curtain sign (ACS), and improved diaphragmatic excursion in the monitored case.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion<\/jats:title>\n                    <jats:p>These findings suggest that severe pulmonary hyperinflation may represent a cause of false-positive A-ACS, likely resulting from diaphragmatic flattening and altered cardiophrenic mechanics.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Clinicians should consider pulmonary hyperinflation in cats presenting with A-ACS to avoid misdiagnosis of pneumothorax and unnecessary interventions. Moreover, this sign may offer valuable insights into respiratory dynamics in feline obstructive airway disease.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fvets.2026.1707703","type":"journal-article","created":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T14:31:08Z","timestamp":1769524268000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["False-positive asynchronous-abdominal curtain sign mimicking pneumothorax in cats with severe pulmonary hyperinflation\u2014case report"],"prefix":"10.3389","volume":"13","author":[{"given":"Pablo A.","family":"Donati","sequence":"first","affiliation":[{"name":"C\u00e1tedra de Anestesiolog\u00eda y Algiolog\u00eda, Facultad de Ciencias Veterinarias, Universidad de Buenos Aires","place":["Buenos Aires, Argentina"]},{"name":"Cooperative Veterinary Intensive Care Unit (UCICOOP)","place":["Buenos Aires, Argentina"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gustavo A.","family":"Plotnikow","sequence":"additional","affiliation":[{"name":"Servicio de Rehabilitaci\u00f3n, Unidad de Terapia Intensiva, Hospital Brit\u00e1nico de Buenos Aires","place":["Buenos Aires, Argentina"]},{"name":"Facultad de Medicina y Ciencias de la Salud, Universidad Abierta Interamericana","place":["Buenos Aires, Argentina"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"S\u00f8ren R.","family":"Boysen","sequence":"additional","affiliation":[{"name":"Department of Veterinary Clinical and Diagnostic Sciences, Faculty of Veterinary Medicine, University of Calgary","place":["Calgary, AB, Canada"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,1,27]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"291","DOI":"10.3389\/fvets.2019.00291","article-title":"Abnormal curtain signs identified with a novel lung ultrasound protocol in six dogs with pneumothorax","volume":"6","author":"Boysen","year":"2019","journal-title":"Front Vet Sci"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"S2","DOI":"10.1111\/vec.13420","article-title":"Clinical and point-of-care ultrasound findings in a case series of cats with high-rise syndrome","volume":"34","author":"Swanstein","year":"2024","journal-title":"J Vet Emerg Crit Care"},{"key":"ref3","doi-asserted-by":"publisher","first-page":"101","DOI":"10.1016\/j.jmu.2017.04.005","article-title":"The curtain sign in lung ultrasound","volume":"25","author":"Lee","year":"2017","journal-title":"J Med Ultrasound"},{"key":"ref4","doi-asserted-by":"publisher","first-page":"429","DOI":"10.1111\/vec.12732","article-title":"Evaluation of the agreement between focused assessment with sonography for trauma (AFAST\/TFAST) and computed tomography in dogs and cats with recent trauma","volume":"28","author":"Walters","year":"2018","journal-title":"J Vet Emerg Crit Care"},{"key":"ref5","doi-asserted-by":"publisher","first-page":"375","DOI":"10.1016\/j.cvsm.2019.10.002","article-title":"Feline asthma: diagnostic and treatment update","volume":"50","author":"Trzil","year":"2020","journal-title":"Vet Clin North Am Small Anim Pract"},{"key":"ref6","doi-asserted-by":"publisher","first-page":"227","DOI":"10.1016\/j.jfms.2003.09.004","article-title":"Feline lower airway disease: a retrospective study of 22 naturally occurring cases from Greece","volume":"6","author":"Adamama-Moraitou","year":"2004","journal-title":"J Feline Med Surg"},{"key":"ref7","doi-asserted-by":"publisher","first-page":"1925","DOI":"10.2147\/COPD.S85659","article-title":"Sonographic evaluation of diaphragmatic dysfunction in COPD patients","volume":"10","author":"Scheibe","year":"2015","journal-title":"Int J Chron Obstruct Pulmon Dis"},{"key":"ref8","doi-asserted-by":"publisher","first-page":"143","DOI":"10.1111\/vec.13360","article-title":"Evaluation of B-lines with 2 point-of-care lung ultrasound protocols in cats with radiographically normal lungs","volume":"34","author":"Rigot","year":"2024","journal-title":"J Vet Emerg Crit Care"},{"key":"ref9","doi-asserted-by":"publisher","first-page":"377","DOI":"10.1111\/vec.12066","article-title":"Anaphylaxis in dogs and cats","volume":"23","author":"Shmuel","year":"2013","journal-title":"J Vet Emerg Crit Care"},{"key":"ref10","doi-asserted-by":"publisher","first-page":"1098612X241275290","DOI":"10.1177\/1098612X241275290","article-title":"Efficacy of ultrasonographic diaphragmatic parameters in distinguishing diaphragmatic dysfunction in cats","volume":"26","author":"Saisawart","year":"2024","journal-title":"J Feline Med Surg"},{"key":"ref11","doi-asserted-by":"publisher","first-page":"708","DOI":"10.1183\/09031936.97.10030708","article-title":"Effect of hyperinflation on the diaphragm","volume":"10","author":"De Troyer","year":"1997","journal-title":"Eur Respir J"},{"key":"ref12","doi-asserted-by":"publisher","first-page":"303","DOI":"10.1016\/0034-5687(80)90062-6","article-title":"Inspiratory muscle activity during induced hyperinflation","volume":"39","author":"Martin","year":"1980","journal-title":"Respir Physiol"},{"key":"ref13","doi-asserted-by":"publisher","first-page":"139395","DOI":"10.1155\/2012\/139395","article-title":"Pendelluft in chronic obstructive lung disease measured with lung sounds","volume":"2012","author":"Vyshedskiy","year":"2012","journal-title":"Pulm Med"},{"key":"ref14","doi-asserted-by":"publisher","first-page":"105761","DOI":"10.1016\/j.tvjl.2021.105761","article-title":"Association between respiratory clinical signs and respiratory localization in dogs and cats with abnormal breathing patterns","volume":"277","author":"Dom\u00ednguez-Ruiz","year":"2021","journal-title":"Vet J"},{"key":"ref15","doi-asserted-by":"publisher","first-page":"242","DOI":"10.3390\/vetsci12030242","article-title":"Emergency dyspnea in 258 cats: insights from the French RAPID CAT study","volume":"12","author":"Abboud","year":"2025","journal-title":"Vet Sci"},{"key":"ref16","doi-asserted-by":"publisher","first-page":"316","DOI":"10.1111\/vec.12150","article-title":"Feline secondary spontaneous pneumothorax: a retrospective study of 16 cases (2000-2012)","volume":"24","author":"Liu","year":"2014","journal-title":"J Vet Emerg Crit Care"},{"key":"ref17","doi-asserted-by":"publisher","first-page":"660","DOI":"10.4142\/jvs.2018.19.5.660","article-title":"Usefulness of transthoracic lung ultrasound for the diagnosis of mild pneumothorax","volume":"19","author":"Hwang","year":"2018","journal-title":"J Vet Sci"},{"key":"ref18","doi-asserted-by":"publisher","first-page":"102","DOI":"10.1097\/LBR.0000000000000525","article-title":"Risk factors for loss of lung sliding in a medical intensive care population with acute respiratory failure","volume":"26","author":"Mallow","year":"2019","journal-title":"J Bronchology Interv Pulmonol"}],"container-title":["Frontiers in Veterinary Science"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fvets.2026.1707703\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,2,24]],"date-time":"2026-02-24T09:13:34Z","timestamp":1771924414000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fvets.2026.1707703\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,27]]},"references-count":18,"alternative-id":["10.3389\/fvets.2026.1707703"],"URL":"https:\/\/doi.org\/10.3389\/fvets.2026.1707703","relation":{},"ISSN":["2297-1769"],"issn-type":[{"value":"2297-1769","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,27]]},"article-number":"1707703"}}