Feline Health Topics for veterinarians Winter 1990 Volume 5, Number 1 Feline Bronchial Diseases Bronchial diseases are characterized by airway more completely. Diagnosis is complicated further obstruction and increased airway restriction. The because more than one disease can be present in a basic anatomy of the cat’s respiratory system may patient (i.e. bronchitis and asthma). actually make it more susceptible to bronchial diseases than other animal species. Those anatomical Coughing and dyspnea are typical hallmarks of differences include an increased number of bronchial diseases, however these signs can indicate seromucous bronchial glands (especially in older other conditions (see Table 2). When cats with all cats) and a thick bronchial wall which is capable of forms of bronchial disease are grouped together and increasing the constriction of the bronchial lumen. compared to a control group, cats most predisposed to bronchial diseases are middle-aged cats (2 to 8 Feline bronchial diseases have previously been years old), female cats and Siamese. In the 65 cases grouped together and frequently called felin e studied at Cornell, the signs noted by owners were: bronchial asthma or chronic bronchitis. Based on a coughing (88%), dyspnea (39%), wheezing (20%), Cornell study, feline bronchial diseases are not all the sneezing (23%), and vomiting (15%). Duration of same and should be subclassified. A proposed the disease is variable. A seasonal incidence was not classification is presented in Table 1. However, more substantiated statistically. clinical and diagnostic studies are required to develop specific criteria to describe feline bronchial diseases Diagnosis Patient History: Inside this issue.. Complete and accurate patient history is a useful aid in diagnosis. Answers to the following questions provide clues as to the type of bronchial disease Feline Bronchial Diseases page 1 present: Proceedings from Canine and Feline How long has the owner been aware of the Reproduction Symposium page 6 problem? The duration of the problem determines if Mark Your Calendar page 6 the disease is chronic (persisting months to years) or subacute (less than 24 hours) or stages in-between. Subject Index page 7 Is coughing productive or nonproductive? Job Opportunity page8 Coughing which produces gagging or spitting up may be indicative of an infection such as bronchitis. Feline Health Topics 2 Does cat have trouble breathing? Does the cat bronchial cytology and culture and thoracic snore or sneeze? Is there nasal or ocular discharge? radiographs. If practical, pulmonary function tests Wheezy or noisy breathing are manifestations of would be ideal in diagnosing bronchial diseases. lower respiratory diseases; whereas sneezing, snoring, Bronchial Cytology!Culture: Transtracheal nasal and ocular discharges are characteristic of upper washing provides cells and fluid from the lower respiratory diseases. airways for cytologic and culture evaluation. A Physical Exam: sample can be obtained by transtracheal aspiration, endotracheal tube bronchial brushing or Observe the cat’s breathing before doing the bronchoscopy. physical examination since the stress of physical contact can cause an increased respiration rate. Cytologic examination of a tracheal wash shows Respiration rate (normal 20-60 per minute), dyspnea, a mucoid exudate with various cell types present, but depth and regularity should be noted. If dyspnea is with an absence of parasite larvae or ova. The Cornell observed, does it occur on inspiration or expiration? study identified the predominant cell types as Inspiratory dyspnea occurs in restrictive diseases eosinophilic (24 percent), neutrophilic (33 percent), such as pneumothorax, pleural effusion, or neoplasia. macrophagic (22 percent), and mixed population of Expiratory dyspnea occurs in obstructive diseases cells (21 percent). Bacterial cultures were positive in such as bronchitis, bronchiectasis, severe pulmonary 24 percent of the cats. edema or asthma. Also, the respiratory pattern provides more diagnostic information. Small rapid breaths are typical of restrictive diseases; deeper slower breaths occur with obstructive diseases. C \ Auscultation of the heart and lungs aids in Feline Health Topics detecting cardiac abnormalities (murmurs and arrhythmias) and pulmonary abnormalities. Late A publication for veterinary professionals inspiratory crackles (sound resembling a crackling The ultimate purpose of the Cornell Feline Health Center is to fire) are heard in restrictive pulmonary diseases. improve the health of cats everywhere, by developing methods Early expiratory crackles are audible in obstructive to prevent or cure feline diseases, and by providing continuing education to veterinarians and cat owners. All contributions are diseases. If wheezing occurs on inspiration, tax-deductible. Director: Fredric W. Scott, D.V.M., Ph.D. extrathoracic obstruction, such as laryngeal paralysis, Assistant Director: John E. Saidla, D.V.M. is the cause. Wheezing during expiration occurs in Editor: Ju n e E. T uttle Secretaries: Sheryl A. Thomas, Gwen Frost, intrathoracic obstruction. Phyllis Dague This publication is made possible, in part, by {Note: Inaccurate thoracic auscultation can occur a grant from 9-Lives Cat Foods. We grate­ fully acknowledge this interest and support if the cat is purring. A technique that has worked in the furthering of feline health. This successfully in the Small Animal Clinic at Cornell acknowledgement of our gratitude is not an endorsement of any particular company or College of Veterinary Medicine is to turn on a water product. faucet in the examination room for about ten seconds. © 1990 by Cornell University on behalf of the Cornell Feline Health Center, College of The cat w ill stop purring for one to two minutes.) Veterinary Medicine, Ithaca, NY 14853. All rights reserved. Permission to reprint se­ lected portions must be obtained in writing. Diagnostic Tests: Cornell University is an equal opportunity, affirmative action educator and employer. Diagnostic tests to evaluate bronchial disease are 3 Table 1. Preliminary Classification of Feline Bronchial Diseases Asthma Acute Bronchitis Chronic Bronchitis Emphysema Definition: Reversible obstructed Inflammation of the Long-standing A pathological airway marked by bronchi which has a short inflammation of the accumulation of air spasmodic contraction of and moderate course. bronchi that is constant in the lungs. Can the bronchi. or characterized by be a sequel to recurrence after periods chronic bronchitis. of quiescence. Age of Cat: Any age, but tend to be Any age Middle to old age. Any age. young adults. More common in Siamese. Clinical Signs: Episodes of paroxysmal Coughing Coughing, dyspnea, and Coughing, dyspnea, dyspnea, with or without wheezing. and wheezing. coughing and wheezing. Diagnostic Tests: Radiographs Usually mild to moderate Prominent bronchial Marked bronchial Marked bronchial prominent bronchial pattern (variable severity). pattern with interstitial pattern with pattern; during episodes of infiltrates frequently overinflation, dyspnea overinflation may present. Collapse of (’"histopathology is occur. right middle lung lobe most conclusive is common. Patchy test) alveolar densities. Overinflation may be present. Bronchial Cytology/Culture Eosinophil is primary cell Macrophages or Neutrophil is primary Neutrophil is type. Cultures are usually neutrophils predominate. cell type, although primary cell type, negative. Most common bacterial eosinophils can be although species cultured are present. Cultures may eosinophils can be Pasturella multocida, be positive for bacteria present. Cultures Bordetella bronchiseptica, or mycoplasma. may be positive for or alpha hemolytic bacteria or Streptococcus sp. mycoplasma. Prognosis: Good. Excellent response Excellent. Responds well Poor for complete Poor. Damage to to therapy. to antibiotics if caused by recovery. Requires the lungs is bacteria. constant treatment. irreparable. Results can differentiate between allergic or bronchitis, or parasitic lung disease. The eosinophilic infectious diseases. In the normal cat there w ill be or neutrophilic exudates occurred more frequently in small amounts of mucus, columnar epithelial cells, cats with moderate to marked bronchial disease. The a few macrophages and occasionally neutrophils. macrophagic exudates were more commonly A marked increase of neutrophils can indicate a associated with mild bronchial disease. bacterial, viral, mycoplasmal or fungal bronchopneumonia, bronchitis, tumors, foreign Radiography: Thoracic radiography will identify bodies or aspiration pneumonia. An increase in and distingush between thoracic airway obstruction, eosinophils is characteristic of asthma, allergic extrapulmonary diseases impairing lung inflation, Feline Health Topics 4 primary pulmonary disease and cardiovascular Thoracic radiographs show large numbers of par­ disease. allel linear shadows radiating toward the lung periphery or ring shadows with small radiolucent Accurate reading requires knowledge of thoracic centers. These structures are thickened bronchial anatomy, skilled interpretation, and proper technique. walls. Air trapping or emphysema is characterized The following are guidelines to obtaining good by lung overinflation which causes flattening of the thoracic radiographs: diaphragm, scallop appearance of the diaphragm, • Use the shortest exposure time appropriate for expansion of the rib cage, and pronounced separation the film/screen combination in use. If