Chronic bronchitis, or chronic cough, is a condition characterized by chronic or recurrent cough associated with mucus secretion in the bronchi and bronchioles not caused by lung disease. It is commonly caused by chronic exposure to irritants like sulfur dioxide or passive cigarette smoking. Bacterial infections can exacerbate symptoms. Diagnosis is based on history, symptoms of persistent cough, and chest x-rays that may show thickened bronchial walls or signs of emphysema. Treatment focuses on minimizing irritant exposure, treating infections, liquefying mucus secretions, and using bronchodilators or cough suppressants to ease symptoms.

1. CHRONIC
BRONCHITIS
(chronic cough)
Prof Dr. Mohamed Ghanem – Vet. Internal Medicine
Benha University- Egypt

2. Definition:
• A condition of chronic or recurrent
cough associated with mucus secretion
in the bronchi and bronchioles which is
not due to lung disease, the cough may
occur in certain season.

3. Causes
Chronic exposure to sulpher dioxide gas. Experimentally produces
chronic cough in dog
Passive cigarette smoking is incriminated to cause the disease in
pet dogs.
Acute infectious tracheobronchitis is a predisposing factor for the
disease.
Bordetella bronchiseptica usually isolated from the bronchi of affected
dogs. They can not produce the disease by themselves.

4. Pathogenesis:
Increase size of
mucus gland
in the wall of
bronchial tree
Increase size of
viscid mucus,
which may result in
obstruction of the
bronchial tree Oedema and increased
cellular infiltration
of airway walls
Narrowing of resp
airways

5. Pathogenesis (continuation)
Continuous irritation by
smokes, SO2 or
infection
hyperplasia and hypertrophy
in the mucus gland
Airway obstruction
Leading to emphysema

6. Symptoms:
It is disease of adult dogs, less common to be seen in dogs
less than 3-5 years.
1. Insidious onset of chronic intractable cough persistent
cough
2. The dogs had been treated several times before
3. The cough is unproductive, dry, harsh and hacking. It is
easily induced by tracheal pressure, or exercise.
4. The cough may occur as bouts of paroxysms.
5. Temperature is normal.
6. Lungs may have normal vesicular or inspiratory coarse
crackles or polyphonic expiratory wheeze.
7. The cough may be moist in the morning follows by
retching.
8. Lethargy, fever and inappetance may indicate bacterial
infection.

7. Diagnosis
1. History of causes or predisposing
factors and also history of previous
continuous illness.
2. Symptoms
3. Radiography.

8. Radiography
A-In non obstruction condition:
Chest radiograph reveals tram- lines in the wall indicating
thickening of the wall. There is also an increase in the interstitial
density.
B- In obstructive condition:
There are hyperlucency and enlargement of the lung field with caudal flattening
or displacement indicating pulmonary hyperinflation or emphysema.

9. Chest X-ray from a dog with chronic bronchitis. The
bronchial walls are thicker than normal

10. Treatment:
The owner should maintain warm environment
especially in winter season.
Minimize the irritating factors as much as you can
for long time to regain the normal structure of the
air –way.
The owner must be informed of the nature of the
disease and the possible causes to avoid.
Rare to cure.

11. 5- In cases of bacterial infections use:
Ampicillin + trimethoprim + sulfadiazine are
very effective. 20 mg/kg b.w. ampicillin + 30
mg/kg of trimethoprim sulphadiazine orally.
Cephalosporins: 14 mg/kg b.w cephaloxin
orally  once daily for 1 week I/M.
Aminoglycoside such as tylosin (tylan) 20
mg/kg b.wt orally.

12. 6- Liquefaction of mucus secretions:
Aerosol
therapy:
•By exposure to water vapor such as
steam of hot shower in the bath room. 2-3
times daily.
•Water vapor + physiotherapy. By
percussion on the chest using cupped
hand to liquefy mucus in the bronchial
tree. Success is achieved when bouts of
productive cough occur.
Expectants:
•Saline expectorant as sodium or
potassium citrate, ammonium chloride or
potassium iodide, they increase less viscid
bronchial secretions.
•Volatile oils: as turpentine, eucalyptus oil.
N.B. patent preparations as mucodyne syrup may be effective

13. 7-
Bronchodilator:
there are 3
mains groups:
•β-adrenergic agonists: such as
epinephrine, isoprotarenol,
metaprotarenol and
sulbutamole are not effective
in pet animals.
•Xanthins: as thiophylline and
its various salts e.g.
aminophylline orally is the
drug of choice.
•Anticholinergic drugs. e.g
atropine sulphate.

14. 8- Suppress cough: orally
during severe paroxysms
otherwise mucus will be
retained in bronchial
tree. e.g codeine

15. www.drghanem.co.nr
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