Download Respiratory Disease and Types of Pneumonia

Respiratory Disease and Pneumonia DRAFT Jan. 27, 2017
Pneumonia is an infection of one or both of the lungs caused by bacteria, viruses, fungi, or chemical
irritants. Pneumonia is basically inflammation of lung tissue effecting gaseous exchange in the
patient.
Upper Respiratory Disease
 Sinusitis
 Pharyngitis
 Laryngitis
 Dyptheria
 Tracheitis
 Bronchitis
Lower Respiratory Disease
 Bronchiolitis
 Pneumonia
Types of pneumonia
1.
Bronchial pneumonia
Also known as bronchopneumonia; affects the tubular structures of the respiratory tree. The
anterior-ventral (A-V) areas of either lungs may be affected. By definition rhinitis, laryngitis,
pharyngitis, tracheitis, bronchitis or bronchiolitis can become pneumonia when the infectious process
extends into the alveoli level of the respiratory tree. Gravity results in the migration of infectious
material into the A-V areas of the lungs. The Bronchial descriptive term reflects the route of viral or
bacterial access to the lung.
Lung consolidation and
 Red Hepatization
 Grey Hepatization
 Lung abscessation
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Most often bronchial pneumonia occurs in a lobar pattern affecting one or more sections (lobes) of
the lungs. In quadruped animals the A-V lobules and lobes are the areas that are first affected due to
proximity; but much larger areas of the lungs can become involved as the infectious materials fill the
lungs in untreated or neglected cases. Occasionally bronchopneumonia can initially affect the lungs
diffusely as a result of inhalation of fine particulates. The most common example if diffuse
bronchopneumonia is dust pneumonia.
Dyspnea results from interference with normal oxygenation of venous blood and excretion of carbon
dioxide waste gas. Filling of the bronchioles and alveoli with exudate results in loss of normal gas
exchange in the effected lung tissue. As bronchioles and alveoli fill with inflammatory exudate the
lung becomes wet, heavier, and firmer than normal, and is referred to as “pulmonary consolidation”.
Consolidation is sometimes referred to by pathologists as “hepatization”. Hepatization means that the
lung feels firm like liver instead of being soft and compressible. This is caused by replacement of air
in the alveoli with exudate.
2.
Pleural Pneumonia
Also sometimes referred to as Fibrinous Pneumonia in large animal veterinary medicine.
Pleural pneumonia is a secondary pleuritis resulting from the extension of an infectious process from
the lung, through the visceral pleura, into the pleural cavity. This sporadic pleuritis will results from
the same micro-organism that is causing the pulmonary pathology. Inflammation and damage to the
pleural surface will result in accumulation of excessive amounts of exudative pleural fluid (pleural
effusion), and the deposition of variable amounts of fibrin on pleural surfaces. Often large masses or
sheets of fibrin may accumulate in the pleural cavity.
Animals with pleuropneumonia are usually depressed, and anorexic due to fever and dyspnea. The
animal may experience respiratory pain resulting in shallow breathing. Pain also causes the animal to
stand with its elbows abducted. There is often a reluctance to move and a stiff gait. Hypoxia and
cyanosis become evident as thoracic effusion results in lungs collapse. Auscultation reveals
tachycardia, decreased air movement sounds ventrally. A friction rubs and crackling sounds may be
auscultated dorsally. Signs of bronchopneumonia; such as coughing, nasal discharge, and purulent
lacrimation may also be seen.
Treatment includes thoracocentesis with drainage of the pleural cavity in addition to antibiotics, nonsteroidal anti-inflammatory drugs and other bronchopneumonia therapy.
If not treated; the fluids and fibrin will compress the lungs, preventing normal lung expansion and
respiratory function. The affected animal will display a rapid and shallow inspiratory dyspnea and may
die as a result of asphyxia.
Contagious bovine plueuropneumonia (CBPP) is caused by: Mycoplasma mycoides mycoides.
CBPP is a reportable foreign animal disease that is not currently present in the US. Mycoplasma bovis
is a similar endemic species of Mycoplasma that causes widespread disease in U.S. cattle. When
signs and postmortem findings, similar to that described above, are seen; the diagnostic tests should
include culture and a Mycoplasma sp. culture should also be included in the culture request.
3.
Interstitial Pneumonia
Interstitial pneumonia (IP) is a type of pneumonia that is primarily inflammation of lung interstitial
tissue, instead of respiratory epithelial tissue. The route of access to the lung may be via the
respiratory tree, or it may be hematogenous. Common causes of IP are influenza viruses (PI3 and
BRSV virus in cattle), food allergies, food origin toxins and respiratory toxins.
 In cattle overconsumption of l-tryptophan, an amino acid, which may be converted by ruminal
microbes into 3 methyl indole (3MI). 3MI is a respiratory toxin that is the cause of an IP
condition referred to as “Atypical Interstitial Pneumonia” (AIP).
 Moldy feeds can cause allergic conditions which present as an interstitial pneumonia.
 Horses exposed to high protein feeds, such as alfalfa, or moldy feeds may develop a
pulmonary allergic interstitial inflammatory condition called “Heaves”.
Toxic gas inhalation, such as:
Nitrogen dioxide: Produced by fermenting silage, in humans it can cause “Silo Fillers Disease”.
Nitrogen dioxide is a colorless odorless gas capable of causing pulmonary edema with symptoms
typical of IP. If left untreated it can lead to pulmonary scarring referred to as bronchiolitis fibrosa
obliterans. Cattle housed in buildings adjacent to fermenting silage can also be affected by nitrogen
dioxide.
Hydrogen Sulfide emission from oil wells have been reported to cause respiratory disease such as
pulmonary irritation and edema. A common effect of exposure to levels above 100 ppm is suppression
of the cytochrome oxidase aerobic pathway which produces ATP via aerobic metabolism. This is the
cause of H2S lethality in humans, cattle and horses.
4,
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Etiologic Agents
Viruses
Bacteria
Mycoplasma
Fungi
Toxins
Gasses
Allergens
5.
Symptoms of pneumonia?
The observational symptoms of pneumonia include:
 Fever
 Depression, apprehension and decreased mentation
 Weakness
 Rapid respiration that worsens with activity
 Loss of appetite
 Inspiratory Dyspnea with rapid respiration is typical of bronchopneumonia, pleuropneumonia
and pleural effusion
 Expiratory Dyspnea is typical with interstitial pneumonia
 Serous nasal discharge is typical of early non-complicated viral infection
 Purulent or cloudy nasal discharge is suggestive of primary or secondary bacterial respiratory
tract infection
 Hypoxia and pale or bluish mucous membranes occur when oxygenation is impaired, usually in
advanced disease conditions
 Rapid pulse
 Coughing is a rare symptom in cattle but a frequent symptom in horses
Symptoms of pneumonia caused by viruses are very similar to bacterial pneumonia. Note the
characteristics of the nasal discharge for a clue to the microbial origin.
Mycoplasma pneumonia has a somewhat different and variable set of symptoms. Cattle infected with
Mycoplasma bovis may be affected by a mild fever, depression, upper respiratory symptoms or
pneumonia with a cough and mucoid expectoration, pleuritis, peritonitis, otitis externa, lameness due
to mycoplasma arthritis and other syndromes.
Diagnosis
Usually made based on your recent health history (such as surgery, a cold, or travel exposures) and
the extent of the illness. Based on these factors, your health care provider may diagnose pneumonia
simply on a thorough history and physical exam, but the following tests may be used to confirm the
diagnosis:
Diagnostic tests
 Chest X-ray. This test takes pictures of internal tissues, bones, and organs, including the
lungs.
 Auscultation and percussion of the sinuses , larynx, trachea, lung field, and heart
 Ultrasonography to
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Blood tests. This test may be used to see whether infection is present and if infection has
spread to the bloodstream (blood cultures). Arterial blood gas testing checks the amount of
oxygen in your bloodstream.
Sputum culture. This test is done on the material that is coughed up from the lungs and into
the mouth. It's often used to see if there's an infection in the lungs.
Pulse oximetry. An oximeter is a small machine that measures the amount of oxygen in the
blood. A small sensor is taped or clipped onto a finger. When the machine is on, a small red
light can be seen in the sensor. The test is painless and the red light does not get hot.
Chest CT scan. This imaging procedure uses a combination of X-rays and computer technology
to produce sharp, detailed horizontal, or axial, images (often called slices) of the body. A CT
scan shows detailed images of any part of the body, including the bones, muscles, fat, and
organs. CT scans are more detailed than regular X-rays.
Bronchoscopy. This is direct exam of the bronchi (the main airways of the lungs) using a
flexible tube (called a bronchoscope). It helps to evaluate and diagnose lung problems, assess
blockages, and take out samples of tissue and/or fluid for testing,
Pleural fluid culture. In this test, a sample of a fluid sample taken from the pleural space
(space between the lungs and chest wall). A long, thin needle is put through the skin between
the ribs and into the pleural space. Fluid is pulled into a syringe attached to the needle and
sent to the lab where it’s tested to find out which bacteria is causing the pneumonia.
Treatment
 NSAIDs
 Steroids
 Antibiotics
 Antihistamines
 Vitamins
 Fluid Therapy
 Inhalation Therapy
 Bronchodilators
Treatment depends on the type of pneumonia you have. Most of the time pneumonia is treated at
home, but severe cases may be treated in the hospital. Antibiotics are used for bacterial pneumonia.
Antibiotics may also speed recovery from mycoplasma pneumonia and some special cases. There is
no good treatment for viral pneumonia. It usually gets better on its own.
Other treatment may include eating well, increasing fluid intake, getting rest, oxygen therapy, pain
medication, fever control, and maybe cough-relief medication if cough is severe.
What are the complications of pneumonia?
Most people with pneumonia respond well to treatment, but pneumonia can be very serious and even
deadly.
You are more likely to have complications if you are an older adult, a very young child, have a
weakened immune system, or have a serious medical problem like diabetes or cirrhosis.
Complications may include:
Respiratory failure. This requires the use of a breathing machine or ventilator.
Acute respiratory distress syndrome (ARDS). This is a severe form of respiratory failure.
Sepsis, in which the infection gets into the blood. This may lead to organ failure.
Lung abscesses. These are pockets of pus that form inside or around the lung. They may need to
be drained with surgery
Key points about pneumonia
Pneumonia is an infection of one or both of the lungs caused by bacteria, viruses, fungi, or
airborne irritants.
There are more than 30 different causes of pneumonia, and they’re grouped by the cause. The
main types of pneumonia are bacterial, viral, and mycoplasma pneumonia.
A productive cough (producing green, yellow, or bloody mucus) is the most common symptom of
pneumonia. Other symptoms include fever, shaking chills, shortness of breath, low energy, and
extreme tiredness.
Pneumonia can often be diagnosed with a thorough history and physical exam. Tests used to look
at the lungs, blood tests, and tests done on the sputum you cough up may also be used.
Treatment depends on the type of pneumonia you have. Antibiotics are used for bacterial
pneumonia, and may also speed recovery from mycoplasma pneumonia and some special cases.
There is no good treatment for viral pneumonia, which usually gets better on its own. Other
treatment may include a healthy diet, more fluids, rest, oxygen therapy, and medicine for pain,
cough, and fever control.
Most people with pneumonia respond well to treatment, but pneumonia can cause serious lung
and infection problems and can even be deadly.
Next steps
Tips to help you get the most from a visit to your health care provider:
Before your visit, write down questions you want answered.
Bring someone with you to help you ask questions and remember what your provider tells you.
At the visit, write down the names of new medicines, treatments, or tests, and any new
instructions your provider gives you.
If you have a follow-up appointment, write down the date, time, and purpose for that visit.
Know how you can contact your provider if you have questions.
Prevention