Recurrent Obstructive Fibrinous Tracheal Pseudomembranes in a Young English Bulldog

Association between respiratory clinical signs and respiratory localization in dogs and cats with abnormal breathing patterns

The diagnostic values of respiratory signs have been under-investigated in pets. The study aim was to explore commonly assumed associations between respiratory signs and disease localization in pets with abnormal breathing patterns (ABP). Dogs and cats with ABP presenting to three hospitals were included if investigations permitted disease localization. Hypothesized associations between respiratory signs and disease location were evaluated via mixed-effects logistic regression. Sensitivity, specificity, and positive diagnostic likelihood ratio were calculated. One-hundred and fifteen dogs and 49 cats with ABP were recruited. Confirmed associations included: inspiratory effort with extra-thoracic airway disease (odds ratio [OR], 9.1; 95% confidence interval [95% CI] 3.0-27.2); expiratory effort with intra-thoracic airway disease (OR, 6.5; 95% CI, 2.3-18.1); paradoxical breathing and attenuation of heart/lung sounds with pleural space disease (paradoxical breathing: OR, 4.5; 95% CI 1.7-12.1; sound attenuation: OR, 11.5; 95% CI 4.0-33.3); decreased nasal airflow and stertor with nasal/pharyngeal disease (nasal airflow: OR, 26.2; 95% CI 8.1-84.8; stertor: OR, 155.2; 95% CI 24.9-968.8); stridor with laryngeal or tracheal disease (laryngeal disease: OR, 39.9; 95% CI 7.6-209.0; tracheal disease: OR, 32.4; 95% CI 4.2-248.0); tracheal sensitivity with bronchial disease (OR, 3.8; 95% CI 1.5-9.6); crackles with pulmonary or bronchial disease (pulmonary disease: OR, 5.4; 95% CI 2.1-13.8; bronchial disease: OR, 3.9; 95% CI 1.6-9.8); and goose honking with tracheal disease (all dogs with goose honking had tracheal involvement). Select respiratory signs provide guidance to localize and prioritize causes of the underlying respiratory disease in pets, allowing targeted interventions in animals with ABP.

Tracheal pseudomembrane secondary to aspiration pneumonia in a 6-year-old Ragdoll

Case summary

A 6-year-old female spayed Ragdoll presented with a 4-day history of acute onset non-productive retching, coughing and anorexia. A complete blood count, serum biochemistry, thoracic radiography and abdominal ultrasound were performed. Initially, aspiration pneumonia was suspected owing to an alveolar lung pattern in the right cranial ventral lung lobes seen on radiographs. The cat did not improve with empirical antibiotic therapy. Bronchoscopy and bronchoalveolar lavage were performed. An intraluminal tracheal mass was identified and removed via endoscopic guidance and gentle traction. Histopathology results were consistent with a fibrinous tracheal pseudomembrane. The cat was concurrently diagnosed with Pseudomonas aeruginosa pneumonia, which was confirmed on bronchoalveolar lavage. Pseudomonas aeruginosa was also cultured within the pseudomembrane. The cat was received antimicrobial therapy for his Pseudomonas pneumonia. In humans, fibrinous tracheal pseudomembranes occur uncommonly as a complication following endotracheal intubation and rarely due to infectious organisms. As there was no prior history of endotracheal intubation, the development of fibrinous tracheal pseudomembrane in this cat was suspected to be secondary to Pseudonomas aeruginosa aspiration pneumonia.

Relevance and novel information

The present case report is the first to describe a tracheal pseudomembrane in a cat. Bronchoscopy-guided gentle traction and subsequent removal of the tracheal pseudomembrane resulted in a complete resolution of the clinical signs.

Obstructive fibrinous tracheal pseudomembrane in a cat

Tracheal intubation (TI) is a common procedure that rarely entails life‐threatening complications. A 1.5‐year‐old female spayed cat presented with acute signs of respiratory distress 5 weeks after undergoing TI. Radiographs revealed a marked, segmental, tracheal narrowing. A hard, 5‐cm‐long, white‐yellowish tissue was identified and removed from the trachea, with subsequent resolution of clinical signs and radiographic changes. Microscopically, the tissue consisted of fibrin and lytic neutrophils, interspaced with optically empty cavities and a few remains of talcum powder and hair shafts. Consequently, a diagnosis of obstructive fibrinous tracheal pseudomembrane (OFTP) was made. A rare complication of TI in humans, OFTP should also be suspected in cats with respiratory distress, a history of TI and radiographic evidence of tracheal narrowing. Based on cases from other species and the cat described herein, the condition can be easily resolved with OFTP removal.