Faculty of Veterinary Medicine, Urmia University Veterinary Research Forum 2008-8140 17 9 2026 09 01 Negative-pressure pulmonary edema due to nasopharyngeal polyps in a cat 681 684 739038 10.30466/vrf.2025.2057596.4723 EN Aritada Yoshimura Animal Medical Center, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan 0009-0004-0585-1805 Naohiro Uchida Animal Medical Center, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan Hiroyuki Ito Ichikawa General Hospital, Kariya Animal Hospital Group, Chiba, Japan Tomoki Maeba Ichikawa General Hospital, Kariya Animal Hospital Group, Chiba, Japan Miori Kishimoto Laboratory of Veterinary Imaging, Cooperative Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan Ryuji Fukushima Animal Medical Center, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan Daigo Azakami Animal Medical Center, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan Laboratory of Veterinary Clinical Oncology, Cooperative Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan Journal Article 2025 04 14 A 5-month-old male Himalayan cat presented with labored tachypnea and abnormal inspiratory sounds (stertor) in the upper airways. Chest and head radiography revealed amorphous interstitial and alveolar patterns in both lung fields and a soft tissue mass occupying the nasopharynx dorsal to the soft palate. The owner reported that the cat had continuously made sustained inspiratory efforts, which had become more severe on the day of visit. Based on these findings, we considered that the clinical signs were due to negative-pressure pulmonary edema (NPPE) caused by a nasopharyngeal polyp. The cat responded well to symptomatic treatments, including oxygen therapy and intravenous furosemide, and was discharged with surgical treatment planned at the secondary hospital. Although the cat had one recurrence of NPPE before the polyp was surgically removed, however, not suffered from NPPE after the polyp disappeared. The NPPE is a rare disease in cats, and its association with nasopharyngeal polyps has not been previously documented. Nasopharyngeal polyps located above the larynx can cause NPPE because mouth breathing is uncommon in cats. Veterinarians should consider NPPE in cats exhibiting inspiratory effort, particularly when chest radiographs show signs of pulmonary edema. Careful and detailed interviews with the owners/caregivers about respiratory patterns and nasopharyngeal examinations are essential. https://vrf.iranjournals.ir/article_739038_e5364c20e646e5e361ab7a675ffd7a65.pdf