Diseases #15 Copy
Bracheocephalism is a condition, not a disease. It is a type of skull structure seen in Boston Terriers, English Bulldogs, Pugs, Persian cats and others. The face has a sort of smushed up appearance and this causes the sinus passages to run tortuous throughout the head. Eyes may appear to extend out more from their sockets (exopthalmic). The heads tend to be rounder than other breeds. The cause is genetic. To maintain a certain breed requires a set of genes that are expressed as the phenotype (appearance) of a particular breed.
Because of the skull structure, many of these breeds have many medical problems. Many are intolerant of heat and have difficulty breathing in those conditions. Because everything is so compact in the back of the throat (pharynx) excessive heat can cause the trachea (windpipe) to close. This is made worse as many of these breeds have an elongated soft palate. This condition is exacerbated if the animal is obese. Eyes tend to be overly exposed making them prone to dry eye and corneal ulcers. The nasal openings (nares) are narrower than normal making it harder to get oxygen into the lungs.
Most bracheocepalic breeds can live normal lives but their anatomical quirks can get them into trouble. Most problems deal with their respiratory tract. Dogs with a longer skull type may breeze through a simple respiratory problem. Not so with these dogs. They will snort, have tons of mucous secretions produced and have general difficulties getting air in and out of the lungs. They always are at a high risk of heat stroke. Their eyes may easily develop conjunctivitis and corneal ulcers that are characterized by conjunctival inflammation and scratches on the front of the eye.
Since most problems revolve around the respiratory system, most of these animals should be radiographed plus a CBC and a Chemistry profile performed. Cultures may be obtained to accurately diagnose the cause of infection.
Diagnosis is made by recognizing all the bracheocephalic breeds and medical problems associated with them. A medical history and exam plus lab data will point the veterinarian in the right direction. The goal is to find an appropriate treatment.
Accurately diagnosing a bracheocephalic dog while it is wide awake is extremely difficult. Not only is the oral cavity small but the tongue is short and thick. Many times the animal has to be sedated to find the exact cause so as to decide on a treatment. This is especially so with elongated palates. Bracheocephalic breeds that have off and on respiratory problems during excitation, excess heat or other causes are prime candidates for soft palate resection. This is usually done via laser surgery. Surgical opening of the nares is another procedure. I have done this on Persian cats. It definitely makes breathing easier. If the animal is obese, it has to lose weight, no ifs or buts. Excess weight makes clinical signs worse.
The outcome or prognosis for most bracheocephalic dogs that undergo soft palate resections, nares enlargement and weight control (if obese) is good. Those dogs that have chronic ailments such as pulmonary or laryngeal disease are at a disadvantage and hence have a much more guarded prognosis.
Female dogs and cats have five pairs of breast. Mammary glands are needed to produce milk to feed nursing newborns. The cause of the majority of breast cancers is estrogen excess. Dogs and cats that develop false pregnancies or irregular estrous cycles are also at a higher risk of developing breast tumors. Small breeds such as: Maltese, Yorkshire Terriers, Toy Poodles and Chihuahuas are at a higher risk of developing breast tumors.
Female dogs and cats that are spayed before their first heat cycle have an almost zero percentage chance of developing breast cancer. Each heat cycle that a female animal goes thorugh increases the chance of developing breast cancer by about 8%. The majority of breast tumors in cats are malignant. Those in the dog are mixed; meaning about half of them are benign adenomas while the others are malignant and can metastasize to the lungs, lymph nodes and liver.
Clinical signs are associated with firm breast masses that occur from the first pair of breasts down to the fifth pair. Tumors that can easily be moved around are usually benign while those that are fixed to the subcutaneous tissues below it are often malignant. Mammary tumors in dogs and cats are most commonly seen in the fourth and fifth pair of glands in the groin or inguinal area. These glands produce much more milk and are much more active than the first three pair.
Chest films are always taken to see if there is any metastasis of the mammary tumor to the lungs. CBC and Chemistry profiles are also run to detect mammary activity elsewhere.
Diagnosis is made by the presence of an intact middle aged female dog that has one or several firm masses over the mammary gland area. Some animals were spayed at an earlier age but after 6 months of age. The actual pathological diagnosis is made by submitted excised mammary gland tissue to determine the exact cellular diagnosis of the mammary tumor.
If the animal may be safely anesthetized, the best treatment is the surgical removal of the mammary gland and mass with or without the removal of associated lymph nodes. I was taught to always spay the dog at the same time to prevent further mammary tumors from developing. Now a days this is controversial. This still makes sense though, since spaying the animal at that time will prevent pyometra, hydrometra and other gynecological diseases from happening. While in the abdomen, it is a good idea to look at the liver lobes and any other organs for any metastatic activity. Some animals, at specialty practices, may receive radiation and other care. If infections are taken care of and seromas are prevented, most dogs and cats do fine post surgery.
The prognosis for breast tumors depends upon the histological diagnosis of the tumors. Complete excision of a benign tumor receives a favorable prognosis while the excision of a malignant tumor, with or without metastasis, receives a much guarded prognosis. The best course is prevention. All female dogs and cats should be spayed prior to their first estrous cycle. Those that are used for breeding should be spayed at about 3-4 years of age. Those individuals that find or become owners of an intact adult female should immediately have her spayed.
The bronchi are the tubes that carry oxygen to the alveolus; the end of the bronchioles where oxygen is exchanged for carbon dioxide. They bifurcate into left and right bronchi. Off of each of these are smaller air tubes. Bronchitis is the inflammation of the tubes; the bronchi. Infections can be acute or more commonly chronic. Causative agents are: bacterial, virus, inhalant allergies, presence of smoke or any other irritant. Any dog or cat can get bronchitis but those that suffer the most are those bracheocephalic dogs (see preceding disease condition) such as the Pug, Persian cat or the English Bulldog.
The hallmark of bronchial disease is inflammation. Inflammation causes excessive production of mucoid secretions. These secretions can occur up and down the bronchial tubes. They clog the airways making it more difficult to breathe. In chronic cases of bronchitis, the lumen (diameter of any hollow organ) of the bronchi decreases. This becomes a vicious circle making it harder and harder for the animal to get oxygen where it is needed. This mechanism is what explains the majority of clinical signs.
The most commonly seen sign associated with acute and chronic bronchitis is a dry, raspy cough that is exacerbated by any type of exercise or excitement. The cough may be productive (coughing up phlegm) or non-productive. Depending on the cause, some dogs will run a low to moderate fever. Excessive exercise makes it difficult to breathe so the respiratory rate will increase and the animal finds itself straining to catch its breath (dyspnea). In severe cases, the dog will have excessive abdominal respiration; meaning very little inspiratory ability of the lung tissue. Animals are also anorexic and are off their food due to discomfort or just being too tired to get to a food bowl.
Lab work will help to identify the cause of the bronchitis. A CBC and Chemistry profile are performed and 2 chest films are taken via standard radiography or other imaging techniques. Radiographs will show excessive bronchiolar infiltration. Cultures of the phlegm or a tracheal wash may be done to identify any infectious agent.
Diagnosis is made by obtaining a solid history and a complete physical exam. Auscultation of the chest will produce sounds of wheezing and moist or dry rales over the chest. Palpating the trachea via the skin will usually elicit a dry hacky cough. The cough heard usually sounds like a goose! Because of the difficulty breathing, the animal abducts (extends its forelimbs) to make it easier for inspiration. Combining the exam and history with lab work makes it pretty straight forward to figure out.
Treatment is based on treating the cause of bronchitis and managing the clinical signs of the disease. Most cases will require antibiotics to treat infectious bronchitis or prevent a secondary bacterial infection in other cases. Allergic cases are treated with corticosteroids or inhalers. Nebulization is one of the best treatments for these animals that make both dogs and cats feel and breathe so much better. This should be done at least 4-5 times per day initially. The nebulization therapy involves inhaling: Mucomyst®, aminophylline, gentomycin and dexamethasone. If the cough is non-productive antitussives such as butorphanol are used. This has to be given often but it also takes away the pain and encourages the animal to rest. Bronchodilators such as theophylline are used to open up the airways to allow as much air in as possible. Pets are sent home on a combination of these drugs. Chronic cases can be difficult to treat and involve cough suppresants such as Hycodan® plus non-systemic corticosteroids such as budesonide. Home supportive care is crucial. Animals should remain in an air conditioned environment and air handler filters changed more frequently. Short walks are okay but use a harnass rather than a leash and collar. This will decrease inflammation and hence the cough reflex.
The prognosis for acute bronchitis is usually good, as long as the owner seeks immediate veterinary care and appropriate therapy is started. The prognosis for chronic bronchitis is guarded in that many of these animals enter a downward spiral where medical care does very little for the animal; even breathing pure oxygen. On the other hand, prior to this, many of these animals can be maintained successfully on medical therapy and corticosteroid inhalers to enjoy a relative good quality of life.
Burn wounds are extremely painful, not only for humans, but for our companion animals. The cause of burns are usually broken down into three groups: heat (themal), chemical and radiation. Thermal causes are the most common and occur in the home the majority of the time. Cats jumping up onto a turned on electric stove or a woodburner in full blaze will suffer burn wounds to the pads. Hot liquids, lamps and excessive use of heating pads can cause burns. Burns are also produced by caustic chemicals such as products containing acids. Radiation causes include those dogs undergoing radiation therapy. In my Ohio practice I had to treat a cat that was put in a microwave oven by a little boy for about half a minute. The cat did survive. Dogs also get into trouble (particularly puppies during teething) by chewing on electrical cords. These produce burns on the mouth or gum tissue.
Regardless of the cause of the burn, cellular damage occurs. Tissues are composed of individual cells and these cells are literally cooked and undergo lysis and when grouped together, tissue damage. This is the most important consideration of burn pathophysiology in a nutshell.
The severity of burns is grouped into three types. First degree burns are those that effect the epidermis or top skin layer. These occur during mild sunburn. Dogs and cats without hair such as the Chinese Crested dog and Sphinx cat are susceptible. Secondary degree burns are those that cause damage down to the dermis or deeper layer. These burns are associated with blistering and require medical care. Third degree burns destroy and char the entire skin surface. The tissue is dead, circulation damaged and the body is prone to bacterial infections. These are dangerous burns.
All burn patients should have a CBC and Chemistry profile done numerous times while being treated for burn wounds; particularly those animals being treated for third degree wounds.
Diagnosis of a burn wound is pretty easy if the burn is noticed by the owner. Some burns may show themselves as time goes on and or be hidden by the animal's hair-coat.
Initial first aid may begin at home. Cold compresses can be applied to thermal wounds such as sunburn. Chemical burns should be flushed with running water to drain off as much contaminant as possible. All burns patients should than receive medical care. The treatment is based on which degree of burn is present, the location of the burn and what percentage of the body is being effected. Blood is drawn to check organ function and an intravenous line is installed with fluid therapy. Burn patients suffer from dehydration. All burn patients (particularly third degree) suffer from intense bacterial infections caused by Pseuodomonas aeringinosa. Intravenous and oral antibiotics are ordered. Surgery is required in third degree burns. The goal is to debribe as much dead tissue away as possible and attempt wound closure. Many animals require grafts but if this is not possible, burn wounds will heal and fill in with scar tissue. Scar tissue does not have hair follicles so the area will be devoid of a hair-coat.
The prognosis for burn patients depends upon the degree of burn and the percentage of the skin surface that has been burned. Primary burns have an excellent prognosis while severe burns that cover 30%-50% of the body surface have a poor prognosis. Antibiotic and fluid therapy are required for a long period of time. Wound healing takes a long time. Best bet is prevention of burns by keeping caustic chemicals away from pets, minimize exposure to the suns ultraviolet rays and do your best to isolate dogs from electrical cord chewing. Trying to keep cats from jumping is futile so if you own a cat always stand by the stove when cooking.
Brucellosis is caused by the bacteria, Brucella canis. This organism is a Gram positive rod that causes reproductive issues and fertility problems in male and female dogs.
Brucella canis is difficult to deal with. Transmission of the disease is during sexual contact during mating season. Since a lot of these dogs have abortions or stillborns, dead puppies are ingested by the mother. This is normal behavior for the bitch but can also transmit the disease. This organism hides out in certain cells in the blood making it difficult to treat. Brucellosis is a zoonotic disease, meaning it can be transmitted to humans. Care must be taken to prevent human exposure.
The classical clinical signs associated with Canine brucellosis are abortions in the third trimester (last 20 days of pregnancy) and future infertility in the male or female animal. Stillborns are also very common. In the male, the penis may be infected as well as the prostate gland. Some animals are also asymptomatic.
Both male and female dog used for breeding should undergo a Brucellosis test. This is extremely important in preventing transmission back and forth.
Diagnosing brucellosis is performed by sending a blood sample to a lab that performs an agglutination test. If it is negative your dog does not have brucellosis. However, there may be false positives so a positive test result should prompt the veterinarian to confirm the diagnosis by other means such as culture of stillborns. As with Babesiosis, a PCR test can be used to diagnose the disease.
There is no effective, complete treatment of the disease. Antibiotics such as doxycycline, over a long period (and others), have been used. This is ineffective in the long run as animals will still have Brucella organisms hiding from the immune system and antibiotics while hiding in certain cells like macrophages. There is little else to be done. Spaying or neutering the animal prevents future sexual transmission but does nothing for the organisms already present. Often euthanasia is performed in these cases.
The prognosis for Brucellosis is poor in most animals. All treatments are ineffective at eliminating the bacterial infection. Care must be taken to minimize human exposure to secretions and body parts associated with Brucellosis. This means gloves plus eye and nose protection.