Pneumonia in Shar-Pei Pups
As you come in the door that afternoon you know something is wrong. Your 3 month-old Shar-Pei pup is not at the door to greet you. You search the house and find him in the family room huddled in the corner, ears down, tail limp, droopy eyes, breathing heavily and coughing softly. He feels warm to the touch. His temperature is 104°F and you know you’ve got trouble.
The scenario above is pretty typical for pneumonia in the Chinese Shar-Pei. It often occurs in pups 8 – 16 weeks old and seems to come out of nowhere. The only specific signs which may suggest pneumonia are heavy breathing usually with an abdominal component and sometimes a productive cough. By the times these signs are present, you have a very sick puppy and generally have very little time to do much about it. Diagnosis must be quick, accurate and specific. A minimal database must include a CBC and a chest radiograph. We are primarily interested in the white blood cell count (WBC). What we want to see in the sick pup is a high WBC with some young white blood cells called “bands”. This would signal an appropriate response and that the pup is fighting the infection. A bad sign would be a normal or low WBC with high numbers of bands. This indicates the infection is winning and this pup may die. Radiographic signs of pneumonia are pretty classic and usually apparent on chest X-rays. Positioning may be less than ideal as the pups will resist being put on their side and we don’t want to fight them too much – depending on the degree of lung involvement stress may overwhelm them. It is also helpful to try to stretch out the wrinkles over the chest when the radiograph is taken. Those folds can often obscure the lung changes seen in pneumonia. Pneumonia appears as fluid in the lungs seen in the ventral (lowest) lung fields and located in the cranial (forward) lung lobes. Fluid may accumulate in one lung lobe, cover multiple lobes and also occur in both sides of the chest. The fluid will often obscure the heart shadow on a chest radiograph. The definitive diagnosis is based on a tracheal wash. In this procedure, a catheter is introduced into the trachea and sterile water is flushed into the trachea and then aspirated back out hopefully with the offending bacteria in it. This sample can then be cultured and an antibiotic sensitivity done. This procedure is usually done under sedation or light anesthesia and has some risk involved in it, especially in a sick pup, but the information gathered is critical to instituting the appropriate antibiotic therapy.
What causes pneumonia in Shar-Pei pups? By the time we have a sick pup the lungs have been infected by bacteria. These are usually Gram (-) bacteria such as E. Coli, Klebsiella and Bordetella. Gram (+) cocci such as Streptococcus may also be isolated. It is also known that viruses such as canine distemper, adenovirus and parainfluenza can also cause pneumonia. Shar-Pei also may have an IgA deficiency which occurs in the vast majority of the dogs. IgA is a protective immunoglobulin found in body secretions such as tears, mucous, saliva, etc. It is responsible for local immunity in the respiratory, gastrointestinal, and urogenital systems as well as the skin. IgA deficiency may predispose an animal to bacterial pneumonia. Ciliary dyskinesis is a condition that has been reported in the Shar-Pei in which the cilia of the respiratory tract are abnormal or not present. Cilia are hair-like projections on the lining of the trachea and larger bronchi which are involved in clearance of debris-laden mucous out of the bronchi. This mechanism is vital in preventing accumulation of bacteria in the bronchi and subsequent development of bacterial pneumonia. It appears that this is a heritable condition. Lastly, Shar-Pei are prone to megaesophagus. This is an abnormality involving the esophagus or “food tube” which can result in accumulation of food and secretions in the esophagus. Regurgitation is a common finding in puppies with this condition and this can lead to aspiration pneumonia. Megaesophagus can often be picked up on chest radiographs underlining the importance of doing chest X-rays in any pneumonia workup. Due to the wide range of underlying causes of bacterial pneumonia it is very important to autopsy any Shar-Pei who dies of pneumonia.
Treatment of pneumonia involves the use of antibiotic therapy based on the culture and sensitivity results obtained via the tracheal wash. Pending getting these results back from the laboratory which may take 2-3 days it is necessary to use “Four Quadrant Therapy”. This is antibacterial therapy effective against all bacterial groups – Gram (+) aerobes and anaerobes and Gram (-) aerobes and anaerobes. My initial choice is an aminoglycoside and a penicillin. Use of injectable medications is indicated initially. Another choice is the use of a fluoroquinolone and a penicillin. This has the advantage of being given orally. Once the culture and sensitivity results are back specific antibiotic therapy is based on those results. I like to use a different antibiotic every 2 weeks for at least 4-6 weeks. The therapy should be continued for 2 weeks after the chest radiographs appear normal. There is a very real danger of not treating pneumonia long enough and having it recur with the possibility that the antibiotic therapy used either selected for a resistant strain of bacteria or a new bacteria is causing the problem. A “smoldering-type” pneumonia develops and can cause respiratory problems for a long time. This is more apt to occur when a tracheal wash – culture/sensitivity is not done. Injectable antibiotics may be used in a nebulizer which allows the antibiotic to be breathed into the deeper airways and reach the lungs. Additional therapy is supportive. Fluids (IV or subcutaneous) are very important to maintain hydration in the sick pup and to keep secretions thin. This allows the normal respiratory defense mechanisms such as coughing and ciliary function to clear the bacteria from the lungs. Use of a humidifier is useful in this regard. Adequate nutrition is vital to maintain energy levels in the pup and prevent secondary disease. Coupage (thumping the chest) is useful to stimulate coughing, mobilizing fluid in the chest and stimulate deep breaths to prevent collapsed lungs (atelectasis). Mild, frequent periods of exercise help to mobilize secretions and maintain the pup’s interest and mental well-being.
Prevention centers around decreasing the pup’s exposure to infectious agents. Check your vaccines and be sure they are in-date and stored properly. Be aware of the adverse effects of stress on puppies. Puppy matches, traveling, etc. may need be in the best interest of the young Shar-Pei pup. Isolate puppies from visiting adult dogs. Clean puppy areas with disinfectants frequently. Isolate any sick puppies and care for them last always going from healthy puppies to the sick ones. The use of Bordetella vaccine may be useful although this bacterial agent probably represents a small number of the pneumonia cases.
Maintaining a high index of suspicion for pneumonia in the 8 – 16 week-old puppy is the best way to discover the problem early and get treatment fast. Also remember that pneumonia isn’t the only condition which can result in a fever in pups – every fever is not pneumonia especially if not confirmed by the complete blood count and chest radiographs.