Cat with breathing trouble from lung lesions and lung lobe twisting

Abstract

A three-year-old male British shorthair cat that had exhibited progressive lethargy and intermittent dyspnoea for 14 days was referred for evaluation of acute respiratory deterioration. Clinical findings included rapid and shallow breathing, pale mucous membranes, sound suppression on the right side, and a subcutaneous haematoma in the right epigastric area. Serum biochemistry analysis showed leukocytosis and thrombocytosis. Radiographs revealed hydropneumothorax, a broken eighth right rib, atelectatic right cranial lung lobe (RCrL), and consolidation of the right middle lobe (RML). Doppler examination revealed sonographic changes in the echotexture of both lobes and venous flow was absent in the twisted RML. Furthermore, bronchoscopy showed proximal narrowing of the cat's RML bronchus. Exploratory surgery via medial sternotomy confirmed torsion of the RML and identified deteriorated gas-containing lesions in the collapsed RCrL. Both lung lobes were removed by standard lobectomy, and postoperative recovery was without major complications. Histopathological examination diagnosed multiple bullae and blebs, with significant subpleural haemorrhages in the atelectatic RCrL, whereas tissue congestion with haemorrhages, necrosis, and thrombosis typical for lung lobe torsion were observed in the RML. No other underlying aetiology was apparent. Two months post-operatively, the cat presented with similar acute onset of dyspnoea and spontaneous pneumothorax and was euthanised at the owner's request. The autopsy revealed identical new emphysematous changes in the contra-lateral lung lobes that had been absent at the time of surgery. Emphysematous lesions, regardless of their origin, should be considered in the etiopathology of lung lobe torsion.