Does pneumonia cause diarrhea


In a person with pneumonia, the airways (bronchi) swell and the air spaces (alveoli) fill with mucus and other fluids.

What is pneumonia?

Pneumonia is an infection in one or both of your lungs caused by bacteria, viruses or fungi. When there is an infection in the lungs, several things happen, including:

  • Your airways swell (become inflamed)
  • The air sacs in the lungs fill with mucus and other fluids

How do the lungs work?

Your lungs’ main job is to get oxygen into your blood and remove carbon dioxide. This happens during breathing. You breathe 12 to 20 times per minute when you are not sick. When you breathe in, air travels down the back of your throat and passes through your voice box and into your windpipe (trachea). Your trachea splits into two air passages (bronchial tubes). One bronchial tube leads to the left lung, the other to the right lung. For the lungs to perform their best, the airways need to be open as you breathe in and out. Swelling (inflammation) and mucus can make it harder to move air through the airways, making it harder to breathe. This leads to shortness of breath, difficulty breathing and feeling more tired than normal.

How common is pneumonia?

Approximately 1 million adults in the United States are hospitalized each year for pneumonia and 50,000 die from the disease. It is the second most common reason for being admitted to the hospital — childbirth is number one. Pneumonia is the most common reason children are admitted to the hospital in the United States. Seniors who are hospitalized for pneumonia face a higher risk of death compared to any of the top 10 other reasons for hospitalization.

Is pneumonia contagious?

Certain types of pneumonia are contagious (spread from person to person). Pneumonia caused by bacteria or viruses can be contagious when the disease-carrying organisms are breathed into your lungs. However, not everyone who is exposed to the germs that cause pneumonia will develop it.

Pneumonia caused by fungi are not contagious. The fungi are in soil, which becomes airborne and inhaled, but it is not spread from person to person.

How is pneumonia spread from person to person?

Pneumonia is spread when droplets of fluid containing the pneumonia bacteria or virus are launched in the air when someone coughs or sneezes and then inhaled by others. You can also get pneumonia from touching an object previously touched by the person with pneumonia (transferring the germs) or touching a tissue used by the infected person and then touching your mouth or nose.

How long do I remain contagious if I have pneumonia?

If you have bacterial pneumonia, you are still considered contagious until about the second day after starting to take antibiotics and you no longer have a fever (if you had one). If you have viral pneumonia, you are still considered contagious until you feel better and have been free of fever for several days.

Who is most at risk for getting pneumonia?

People who have an increased risk of pneumonia include:

  • People over the age of 65 and infants under age 2. The weakening immune system of older people makes them less able to fight off illnesses. Similarly, the immune system of infants is still developing and not at full-strength, making them more susceptible to infection.
  • People with a health-caused weakened immune system. Examples include:
    • People who are receiving chemotherapy
    • Transplanted organ recipients
    • People who have HIV/AIDS
    • People with autoimmune disease (such as lupus, multiple sclerosis, inflammatory bowel disease, rheumatoid arthritis) and who are taking medications that suppress the immune system.
  • People who have health conditions that affect the lungs or heart. Examples include:
    • Cystic fibrosis
    • Asthma
    • Chronic obstructive pulmonary disease
    • Emphysema
    • Bronchiectasis
    • Pulmonary fibrosis
    • Interstitial pneumonia
    • Uncontrolled diabetes
    • Heart disease
    • Sarcoidosis
  • People who have neurological conditions that make swallowing difficult. These people are at risk for pneumonia caused by aspiration. Examples include:
    • Dementia
    • Parkinson’s disease
    • Stroke
  • People who are in the hospital. In particular, people in the ICU or anyone recovering who spends a large amounts of time lying on their backs. This position allows fluids, mucus or germs to settle in the lungs. People who need ventilators to breathe are at even greater risk since they have a difficult time coughing up germs that could cause a lung infection.
  • People who smoke or drink alcohol. Smoking damages lung tissue and long-term alcohol abuse weakens the immune system.
  • People who are exposed to toxic fumes, chemicals or secondhand smoke. These contaminants weaken lung function and make it easier to develop a lung infection.
  • Pregnant women. Being pregnant increases the risk of developing pneumonia. This is due to the immune system of a mother not working at full strength because the body is working harder to support the growth of the baby.

What causes pneumonia?

Pneumonia can be caused by a wide variety of bacteria, viruses or fungi. Pneumonia is most commonly classified by the type of germ that causes it and by the location where the person became infected.

Community-acquired pneumonia is the most common type of pneumonia. This type of pneumonia occurs outside of a hospital or other healthcare facility. Causes include:

  • Bacteria: Streptococcus pneumoniae is the most common bacterial cause of pneumonia.
  • Mycoplasma pneumoniae and other atypical bacteria: Other types of bacteria with unique features can cause different types of pneumonia. These include Mycoplasma pneumoniae (causes “walking” pneumonia), Chlamydia pneumoniae (causes Chlamydia pneumonia) and Legionella pneumoniae (causes Legionnaires’ disease).
  • Viruses: Any virus that causes a respiratory tract infection (infections of the nose, throat, trachea , and lungs) can cause pneumonia. The viruses that cause colds and flu (influenza) can cause pneumonia.
  • Fungi (molds): Pneumonia caused by fungi is the least common as pneumonia. Fungus in the soil in certain parts of the United States can become airborne and cause pneumonia. One example is valley fever.

Hospital-acquired pneumonia develops during a stay in the hospital for another illness. This type of pneumonia can be more serious because the person is already sick and antibiotics typically used may be less effective. Bacteria adapt and change over time when exposed to antibiotics, making them less effective (called antimicrobial resistance). People in hospitals spread their drug-resistant bacteria to others, leading to more severe and difficult-to-treat cases of pneumonia. People who are on breathing machines (ventilators) are at increased risk for hospital-acquired pneumonia.

Long-term care facility-acquired pneumonia occurs in long-term care facilities (such as nursing homes) or outpatient, extended-stay clinics. Like hospitalized patients, drug-resistant bacteria are found in this setting.

Aspiration pneumonia is another type of pneumonia. Aspiration is when solid food, liquids, saliva or vomit go down the trachea (windpipe) and into the lungs instead of going down the esophagus and into the stomach. If you can’t cough up these substances, these particles remain in lung tissue and can become infected and pneumonia may develop.

What are the signs and symptoms of both bacterial and viral pneumonia?

Symptoms of pneumonia can range from mild (cold- or flu-like symptoms) sometimes called “walking pneumonia” to severe. How serious your case of pneumonia depends on the particular germ causing pneumonia, your overall health, and your age.

Bacterial pneumonia: Symptoms of bacterial pneumonia can develop gradually or suddenly. Symptoms include:

  • High fever (up to 105° F)
  • Tiredness (fatigue)
  • Trouble breathing: rapid breathing or shortness of breath
  • Sweating
  • Chills
  • Cough with mucus (might be greenish in color or contain a small amount of blood)
  • Chest pain and/or abdominal pain, especially with coughing or deep breathing
  • Loss of appetite
  • Confused mental state or changes in awareness (especially in older adults)

Viral pneumonia: Symptoms usually develop over a period of several days. Early symptoms are similar to flu symptoms, which include:

  • Fever
  • Dry cough
  • Headache
  • Sore throat
  • Loss of appetite
  • Muscle pain
  • Weakness

Additional symptoms appearing about a day later include:

  • Higher fever
  • Cough with mucus
  • Shortness of breath

Are symptoms of pneumonia different in the very young and in seniors?

Some babies and infants with pneumonia may not show any signs of infection. When they do show symptoms, those symptoms may include:

  • Restlessness
  • Increased tiredness (fatigue)
  • Vomiting
  • Cough or fever
  • Decreased intake of fluids or food

Older adults may have milder symptoms and may not have a fever. A sudden change in mental state is sometimes a sign of pneumonia in this age group.

What are the complications of pneumonia?

Anyone can experience complications from pneumonia. However, people in high-risk groups are more likely to develop complications, including:

  • Breathing difficulties: Pneumonia can make breathing difficult. Pneumonia plus an existing lung disorder (such as COPD, emphysema, asthma) can make breathing even more difficult. Breathing difficulties may require a hospital stay to receive oxygen therapy or breathing and healing assistance with the use of a breathing machine (ventilator).
  • Fluid buildup in the lungs (called pleural effusion or “water on the lungs”): Pneumonia can cause a buildup in the fluid between the membranes that line the lungs and the inside of the chest cavity. It is a serious condition that makes breathing difficult. Pleural effusion can be treated by draining excess fluid with a catheter, chest tube or by surgery.
  • Bacteria in the bloodstream (bacteremia): The bacteria that cause pneumonia can leave your lungs and enter your bloodstream, spreading the infection to other organs. This condition is treated with antibiotics.
  • Lung abscess. A lung abscess is a pus-filled cavity in the lung that is caused by a bacterial infection. It can be treated by draining the pus with a long needle or removing it by surgery.

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Recovering from pneumonia

Pneumonia can be a serious illness that takes weeks or months to recover from.

Once you start taking antibiotics, your symptoms should begin to improve. Recovery times vary a lot from person to person and depend on your general health, age and how severe your pneumonia is. If you are diagnosed with pneumonia and your symptoms don’t improve in 48 hours, or if they get any worse, call 111 or 999 for a reassessment.

It’s impossible to say exactly how quickly you’ll recover, but here’s an idea of what to expect:

1 week

your fever should be gone

4 weeks

your chest will feel better and you’ll produce less mucus

6 weeks

you’ll cough less and find it easier to breathe

3 months

most of your symptoms should be gone, though you may still feel tired

6 months

you should feel back to normal

You’ll recover gradually. You can help by eating well and doing some exercise including deep breathing exercises.

At first, you’ll need plenty of rest. As you begin to feel better, you can start to be a bit more active, but don’t push yourself too hard. Start off by getting out of bed and moving around for a few minutes each day. As your symptoms improve and you have more energy, you can increase your activity. Speak to your doctor about how much exercise you should do as you recover.

Exercising your lungs may also help. You can do this by taking long slow deep breaths or blowing through a straw into a glass of water. Deep breathing is also good for clearing the mucus from your lungs: breathe deeply 5 to 10 times and then cough or huff strongly a couple of times to move the mucus. Ask your doctor if breathing exercises could help you.

You can find out more about using breathing exercises to clear your lungs from the Association of Chartered Physiotherapists in Respiratory Care. They’ve produced an information leaflet about the Active cycle of breathing techniques that you can read.

If your symptoms are slow to disappear, if you’re over 60 or you smoke, you should have a chest X-ray 6 weeks after you started your antibiotics. This is to check that the infection has gone from your lungs.

Further information

Call our helpline on 03000 030 555, where our friendly team will be happy to talk about your concerns and answer your questions.

Pneumonia 101: What You Need to Know

What Types of Pneumonia Are There?

The severity of the infection depends on many factors, including your age and overall health.

“A lot of treatment aspects, as well as outcome, depend on the person, as well as the type of pneumonia they have,” says Dr. Barron. “Sometimes you’ll be fine just resting, but if you have things like trouble breathing, you should get to a doctor right away.”

Knowing the cause of a lung infection is important for determining which type of pneumonia you have, how you got it, and how to treat it.

Here’s what you need to know about the different types of pneumonia:

Community-Acquired Pneumonia

Also known as CAP, this is the most common form of pneumonia because you can catch it in public places, such as at school or work. It can be caused by bacteria, viruses, or fungi. (4)

You can also develop CAP after you get a common viral infection, such as a cold or the flu.

The illness ranges from mild to serious and, if left untreated, can lead to respiratory failure or death.

Bacterial CAP is usually more serious than other types and is more common among adults. Atypical pneumonia, often called walking pneumonia, is a milder form.

Viral and bacterial pneumonia share some common signs, but doctors can often distinguish between them by a patient’s symptoms.

Various types of bacteria are responsible for the illness. In most cases, the bacteria will enter the lung during inhalation, but it can also go through the bloodstream if other parts of the body are infected.

Streptococcus pneumoniae, also known as pneumococcal pneumonia, can be treated with antibiotics. But according to the CDC, many types of bacteria, including some S. pneumoniae (pneumococcus), are resistant to those antibiotics, which can lead to treatment failures. Pneumococcal pneumonia causes up to 175,000 hospital admissions a year in the United States. (5)

You can also have a pneumococcal infection without having pneumonia. For example, pneumococcal infections also cause more than three million ear infections in children every year.

Risk factors for bacterial CAP include:

  • Having an underlying lung disease, like asthma or COPD
  • Having a systemic disease, such as diabetes
  • Having a weakened immune system
  • Being very young or very old
  • Being disabled
  • Abusing alcohol
  • Smoking

Depending on how sick you are and whether or not you have any other health conditions, your doctor may treat you for bacterial pneumonia with antibiotics either at home or in the hospital.

Viral CAP, particularly the respiratory syncytial virus (RSV), is the most common cause of pneumonia in children younger than two years old. (6)

Although viral pneumonia is generally less severe than bacterial pneumonia, viral infections caused by certain flu viruses, such as severe acute respiratory syndrome (SARS), can be very serious.

Antibiotics are ineffective against viral pneumonia. Your doctor will most likely treat the symptoms — fever, cough, and dehydration.

You or your child may need to be hospitalized if your viral pneumonia symptoms become severe.

Fungal CAP is most common in people with an underlying health problem or a weakened immune system, including those with HIV or AIDS and people undergoing treatment for cancer. It’s treated with antibiotics or antifungal medication. (7)

Getting a vaccination against pneumococcal pneumonia reduces your risk for CAP.

Healthcare-Associated Pneumonia

This refers to an infection that develops in someone being cared for in a healthcare facility, such as a hospital or nursing home. If you’ve been hospitalized or admitted into a long-term nursing or rehab facility, you may be at risk for more deadly forms of pneumonia. (8)

Symptoms of this type of pneumonia are more serious and may include shortness of breath, high fever, and chest pain.

Hospital-Acquired Pneumonia

As the name suggests, this develops during a hospital stay for a different health problem. People who are on machines to help them breathe are particularly prone to developing hospital-acquired pneumonia.

Hospital-acquired pneumonia usually needs to be treated in the hospital with intravenous antibiotics.

Aspiration Pneumonia

This can develop after a person inhales food, liquid, gases, or dust.

A strong gag reflex or cough will usually prevent aspiration pneumonia, but you may be at risk if you have a hard time swallowing or have a decreased level of alertness.

A form of aspiration pneumonia, chemical- or toxin-related pneumonia is caused by the inhalation of chemical fumes, as through an exposure to a mix of ammonia and bleach, or in the breathing in of kerosene or some other noxious chemical.

This type of pneumonia can also occur in older people with poor swallowing mechanisms, such as stroke victims, who actually can inhale the acidic contents of their stomachs, causing aspiration pneumonia.

This causes inflammation without bacterial infection. These pneumonias can sometimes be difficult to treat, especially because the patients are sicker to begin with.

Once your lungs have been irritated by breathing in food or stomach contents, a bacterial infection can develop.

Some conditions that may put you at risk for aspiration pneumonia include:

  • Overuse of drugs or alcohol
  • Seizure
  • Head injury or anesthesia
  • Gastroesophageal reflux disease (GERD)
  • Various neurological diseases
  • Chronic lung disease, such as COPD

Symptoms of aspiration pneumonia include cough, increased sputum, fever, confusion, and shortness of breath.

Treatment may include breathing assistance and intravenous antibiotics given in the hospital.

You can prevent complications by not eating or drinking before surgery, working with a therapist to learn how to swallow without aspirating, and avoiding heavy use of alcohol.

Opportunistic Infection

Finally, pneumonia that develops in people with a weakened immune system is often referred to as an opportunistic infection.

You’re more at risk for this type of pneumonia if you have a chronic lung disease, have HIV or AIDS, or have had an organ transplant.


Sepsis and septic shock can result from an infection anywhere in the body, including pneumonia. Pneumonia can be community-acquired, meaning that a person becomes ill with pneumonia outside of the hospital or a healthcare facility. Pneumonia can also be caused by a healthcare-associated infection (HAI), which affect 1.7 million hospitalizations in the United States every year. An HAI is an infection that is contracted by people while the hospital for a different reason, such as surgery or treatment for another illness.

Sometimes incorrectly called blood poisoning, sepsis is the body’s often deadly response to infection. Sepsis kills and disables millions and requires early suspicion and rapid treatment for survival.

Sepsis and septic shock can result from an infection anywhere in the body, such as pneumonia, influenza, or urinary tract infections. Worldwide, one-third of people who develop sepsis die. Many who do survive are left with life-changing effects, such as post-traumatic stress disorder (PTSD), chronic pain and fatigue, organ dysfunction (organs don’t work properly) and/or amputations.

The most common source of infection among adults is the lungs.

Pneumonia is an infection in the lungs. The infection can be only in one lung, or it can be in both. There are several causes of pneumonia but the most common are:

  • Bacteria
  • Virus
  • Fungus

Left untreated, pneumonia can be deadly. In the days before antibiotics, it’s estimated that about one-third of those who developed bacterial pneumonia died.


Some people can have pneumonia and not know it, but the most common signs and symptoms of pneumonia are:

  • Fever
  • Cough, with phlegm
  • Shortness of breath
  • Sweating
  • Shaking chills
  • Headache
  • Muscle pain
  • Fatigue
  • Chest pain with breathing

You do not have to have all these symptoms to have pneumonia.

Who is at higher risk for developing pneumonia?

While anyone can develop pneumonia, some people are at higher risk than others. These include:

  • The elderly
  • The very young
  • People who recently had a cold or influenza
  • Smokers
  • Having a respiratory illness, such as chronic obstructive pulmonary disease (COPD)
  • Exposure to certain inhaled toxins
  • Having recently had surgery
  • People in intensive care units

What is the treatment for pneumonia?

Treatment for pneumonia depends on the type of pneumonia that you have.


Bacterial pneumonia is treated with antibiotics. The type of antibiotics your doctor may choose depends on the bacteria causing the infection. (Sepsis and Bacterial Infections) If you are given a prescription for antibiotics, it is essential that you finish all the medication, even if you start to feel better. You will begin to feel more like yourself before the infection is completely gone and if you stop taking the medications before the infection disappears, you could get a more serious pneumonia that can’t be treated as easily.


Viral pneumonia can’t be treated with antibiotics; they will not do any good. In general, there isn’t much that can be done for viral pneumonia other than advising that you rest and take in plenty of fluids to stay hydrated. In some cases, doctors may prescribe an anti-viral medication, but this is not common.


Fungal pneumonia is treated with medications called anti-fungals.

Preventing pneumonia

Pneumonia may be prevented in some cases. If you have surgery that requires general anesthetic, you could be at risk for developing bacterial infection. To lower the risk, you will likely be encouraged to get up and out of bed very quickly after the surgery. If it isn’t possible to get up and move around, you will be encouraged to breathe deeply and cough on a regular basis. This is to help keep your lungs clear.

There is a vaccine that can help prevent a common type of pneumonia called pneumococcal pneumonia. It is caused by a bacterium called Streptococcus pneumoniae. There is also a vaccine that doctors can give children to decrease the risk of developing one of four types of infections:

  • Meningitis (infection in the brain)
  • Bacteremia (infection in the blood)
  • Otitis media (infection in the middle ear)
  • Pneumonia

The vaccine is often recommended for the elderly and for people who are at high risk of developing pneumonia. If you fall into one of those categories, you may want to discuss this with your doctor.

If you suspect sepsis, call 9-1-1 or go to a hospital and tell your medical professional, “I AM CONCERNED ABOUT SEPSIS.”

The information here is also available as a Sepsis Information Guide, which is a downloadable format for easier printing.

Would you like to share your story about sepsis or read about others who have had sepsis? Please visit Faces of Sepsis, where you will find hundreds of stories from survivors and tributes to those who died from sepsis.

Pneumococcal Pneumonia Presenting as New-Onset Seizure

A febrile 65-year-old woman who had suffered a new-onset seizure was brought to the emergency department. The patient—a cigarette smoker—was not coughing and had neither chest pain nor a significant medical history. Her temperature was 39.4°C (103°F). She had nuchal rigidity and Kernig’s and Brudzinski’s signs of meningeal irritation. Lung auscultation revealed signs of right middle lung consolidation. Her white blood cell count was 1,200/µL. A chest film, seen here, showed a masslike density in the right midlung. The suspected diagnosis was a pulmonary neoplasm with possible bone marrow and intracranial metastasis, yet nonenhanced CT of the head revealed no pathologic changes. Cerebrospinal fluid examination showed evidence of bacterial meningitis, and latex examination demonstrated pneumonia caused by Streptococcus pneumoniae. This organism grew in blood and induced-sputum cultures.

The patient was treated with intravenous antibiotics and made a full recovery in 3 weeks. At that time, a second chest film showed resolution of the density. The patient has remained healthy throughout the ensuing 2 years.

Dr Samer Alkhuja of Greenwich, Conn, explains that pneumococcal pneumonia may present radiographically as a lobar or multilobar consolidation that resembles a pulmonary neoplasm. Nevertheless, the presence of fever and signs of meningeal irritation should direct further investigation toward an underlying infection, rather than a neoplastic process. Here the patient’s seizure was related to meningitis.

Pneumonia is a condition characterized by “inflammation” of the lung. In this situation, inflammation refers to an irritation in the lungs that causes the body to respond. One example of a source of irritation would be bacteria in large numbers that cause the body to attempt killing these foreign invaders. As a result, fever, lethargy, and other symptoms may result. Pneumonia results in an inability to oxygenate the blood, leading to lethargy and shortness of breath. Inflammation also stimulates excessive secretion of airway fluid and mucus, resulting in cough and difficulty breathing. Pneumonia is more common in the dog than the cat, and the most common causes of pneumonia are infectious in origin.

Infectious organisms that can cause pneumonia in dogs and cats include bacteria, fungal organisms, viruses, parasites and protozoa.

Aspiration of gastrointestinal contents during vomiting or regurgitation episodes or following a seizure can also lead to severe pneumonia. The inflammatory damage is due to both bacteria in the fluid and injury caused by acid. Inhalation of a foreign body such as a grass awn or stick is fairly common in certain geographic areas and generally results in both bacterial and mechanical inflammation in the lung.

In young animals, viral infection can predispose the lungs to bacterial invasion, and true pneumonia results. “Kennel cough” is the name given to a syndrome caused by viruses and bacteria. It usually results in mild symptoms, mild or no pneumonia, and it resolves within 5 to 7 days. Severe symptoms in combination with poor appetite could indicate pneumonia, a complication of kennel cough. This disease can be difficult to distinguish from pneumonia associated with canine distemper virus, which can attack the nervous system after causing respiratory signs. Young animals can also develop pneumonia because of an abnormal immune system or an inability to respond to an infection. Specific diagnostic tests can be required in these instances.

An additional cause of pneumonia that can be seen in dogs is a “hypersensitivity response” within the lung triggered by parasitic infection, allergens, irritants, or unknown causes. It is important to rule out infectious disease in these animals and search for underlying heart or lung parasites to provide the most beneficial therapy. Determining the cause of pneumonia is always required in order to provide rapid and appropriate treatment.

Symptoms of bacterial pneumonia in dogs and cats may include a moist or productive cough, rapid respiratory (breathing) rate, nasal discharge, loud breathing sounds, malaise/depression, loss of appetite, and/or weight loss. These signs of illness and the presence of a moist cough for more than 2 or 3 days should prompt consultation with your veterinarian. Young animals in particular can become dehydrated easily because of a combination of fever and lack of water intake.

Some fungi or parasites are more prevalent in different regions of the country, so it is important to alert your veterinarian to any recent travel outside of your area. Your veterinarian will search for evidence of pneumonia by completing a thorough physical examination and performing various diagnostic tests.

Listening to the chest cavity often reveals loud bronchial noises and moist crackles throughout the lung fields. A complete blood count (CBC) is used to evaluate the body’s response to infection by assessing the numbers and types of white cells present. The total number of white cells is usually increased in a dog or cat with pneumonia. Increased neutrophils (a type of white blood cell) are exposed when bacteria are the cause of pneumonia. Parasites or a hypersensitivity response can cause an increase in eosinophils (a type of white blood cell) and fungal infection usually results in increases in both neutrophils and monocytes (another white blood cell).

Your veterinarian may also elect to perform a blood chemical profile and urinalysis to make sure that the liver and kidneys are functioning properly prior to therapy. In cats, blood tests are often performed to rule out leukemia or immunodeficiency virus infection in conjunction with pneumonia. Some fungal infections or protozoal infections can be diagnosed in dogs or cats with blood tests; however, analysis of specimens from the lungs may also be required.

Chest x-rays are always recommended when pneumonia is suspected. The x-ray pattern helps determine the most likely cause of pneumonia and also assesses the severity of the disease. In some instances, an inhaled foreign object might be seen in the airways, although many objects cannot be seen and blend in with the lung tissue or cause consolidation (increased whiteness) on the x-ray. Bone and metal objects usually can be seen.

Depending on the changes that are seen on x-ray and your animal’s general health, your veterinarian may recommend light sedation or anesthesia to obtain samples from the airway for culture and analysis. Airway sampling through a tracheal wash or bronchoscopy with bronchoalveolar lavage may be offered. If a foreign object is suspected as the underlying cause of pneumonia, bronchoscopy or surgery is usually required for removal and treatment of the pneumonia.

Some animals with pneumonia require treatment in the hospital. This is particularly true when your pet is dehydrated or requires oxygen therapy because supportive care is important in aiding resolution of pneumonia. In addition to these treatments, animals often receive “nebulization” and “coupage” therapy to remove excessive secretions from the lung and improve breathing. This type of therapy is achieved by supplying moisture-laden air to your dog or cat in a closed environment and then lightly tapping the chest with a cupped hand to loosen mucus. Sometimes this therapy is also required when animals are discharged from the hospital. Ultrasonic nebulizers can be purchased for home use from a hospital supply company or respiratory therapy unit.

Because the mechanical removal of mucus and infectious organisms is so important in animals with pneumonia, cough suppressants should not be used early in the course of disease because infectious secretions can become trapped in the airways and worsen pneumonia.

Bacterial pneumonia requires treatment with specific antibiotics that are directed against the organisms isolated from the lung. All antibiotics prescribed must be administered to your pet for the full course of treatment. Before stopping any medications, please consult with your veterinarian. Fungal pneumonia can be treated with intravenous and/or oral agents to kill or slow the growth of particular fungus.

Prolonged therapy is often required. If lung hypersensitivity is the cause of pneumonia, steroids may be required for treatment; however, these are prescribed only when infectious causes of pneumonia have been ruled out.

Any medication used to treat pneumonia can be associated with side effects such as loss of appetite, vomiting, or diarrhea. Steroids cause excessive drinking, urinating, and eating. Any adverse responses should be reported to your veterinarian immediately because changes may be required to restore your animal’s health.

Launching November 2016, the Reference Module combines thousands of encyclopedic and comprehensive articles into one interdisciplinary resource that is continuously reviewed and updated, essential in the rapidly evolving fields of Neuroscience and Biobehavioral Psychology. The following is an exclusive preview excerpt taken from the forthcoming Reference Module in Neuroscience and Biobehavioral Psychology.

About 5% of patients with an infection of the central nervous system will experience a seizure. A seizure may be the presenting symptom, or only one manifestation, of the infection. Common infections of the central nervous system that may present with seizures include: herpes simplex, cytomegalovirus, arbovirus, human immunodeficiency virus, neurocysticercosis, malaria, toxoplasmosis, bacterial meningitis and brain abscess. The seizures may be due to direct invasion of brain tissue by the infecting organism, production of toxins by the organism or production of inflammatory mediators by the brain. Infectious processes in the brain can lead to breakdown of the blood–brain barrier and brain edema. Severe systemic infections can also be associated with seizures, even if the infection is not present in the central nervous system. In this instance the seizures are most likely due to hypoxia or other severe metabolic changes, such as hyponatremia, that are the result of the overwhelming infection. In all cases, treatment for the seizures associated with infection usually involves treatment of the underlying infection.

Bacterial infections in the central nervous system are less likely to cause seizures than viral infections. However, generalized convulsions may occur with bacterial meningitis. Compared to other bacteria, infections with Haemophilus influenzae are more commonly associated with seizures. The mechanism of the seizures is not known. As with other infectious processes, it has been postulated that the seizures are either a result of the primary infection or due to the inflammatory response to the bacterial infection. To date there is not much data for either possibility.

Encephalitis due to a viral infection of the brain can be associated with both focal and generalized seizures. Viral encephalitis is characterized by neuronal and glial degeneration, inflammatory infiltrate, edema, and tissue necrosis. Herpes simplex virus is the most common pathogen associated with seizures in cases of viral encephalitis. But, seizures occur in approximately 85% of children infected with Japanese encephalitis and up to 10% of adults with West Nile virus. Equine encephalitis, St. Louis encephalitis, cytomegalovirus and rabies have also been reported to cause seizures. Finally, it has been estimated that 2–5% of HIV-infected patients have seizures due to the primary infection of the brain by the virus.

The issues surrounding the relationship between herpes virus infections of the central nervous system and seizures is a bit more complicated. Infection with herpes virus, particularly herpesvirus 6B (HHV-6B) is quite common. Recently, it has been questioned whether the association between acute infection with HHV-6B and seizures in infants less that 1 month old is a causal relationship. It could be that the infection is causing the seizures, but it is also possible that infants susceptible to the infection are those most likely to have seizures. The evidence is not clear one way or the other. Herpesviruses can also result in a latent or persistent infection. This persistent infection has been implicated in febrile seizures and some forms of epilepsy – in the absence of symptomatic encephalitis.

HHV-6B has been found in resected tissue from a substantial proportion of patients with temporal lobe epilepsy. The virus is found in astrocytes in this tissue. The current hypothesis is that the presence of the virus is a result of an early infection and its continued presence somehow lowers the seizure threshold or likelihood of developing epilepsy. Herpes is easily reactivated, particularly

by other viral infections. It is possible that reactivation of the virus results in a series of consequences that result in a lowering of the seizure threshold. One hypothesis is that reactivation of HHV-6 alters gene expression in astrocytes, which in turn alters glutamate pathways. Thus the seizures could be due to an action of the reactivated virus or a secondary action initiated by the presence of the virus in the latent form. There is not enough data to state definitively one way or the other.

Other infections that involve the central nervous system have been reported to cause seizures. Neurocysticercosis, infection of the central nervous system with the cyst form of tapeworms, is the most common parasitic infection of the brain. In developing countries, up to 50% of adult-onset epilepsy is due to neurocysticercosis. Malaria is estimated to spread into the central nervous system in approximately one third of the cases and cerebral malaria can present with seizures. The incidence of acute seizures in neurosyphilis is 14–60%. Infectious diseases in which seizures have been reported, but are not typically the presenting feature, include: rubeola, schistosomiasis, trichinosis, paragonimiasis, echinococcosis, trypanosomiasis, typhus and amebiasis.

In summary, infections of the central nervous system are clearly associated with seizures, either during the acute infection or as a delayed response. The mechanism underlying these seizures are not understood and are most likely dependent on the infectious agent and time course of the infection. In addition, inflammatory processes in the brain have been implicated in a number of cases and could be the underlying cause of seizures in some, if not all, infections.

This exclusive preview excerpt was taken from the forthcoming Reference Module in Neuroscience and Biobehavioral Psychology. Launching November 2016, the Reference Module combines thousands of encyclopedic and comprehensive articles into one interdisciplinary resource that is continuously reviewed and updated, essential in the rapidly evolving fields of Neuroscience and Biobehavioral Psychology. The article this excerpt was taken from is an updated article, the previous article was reviewed and deemed out of date and therefore was updated to be included in the new Reference Module. Articles within the Reference Module are on a review cycle to keep them up to date. Learn more here.

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