PathophysiologyBMS 243

The Respiratory System Pneumonia

Dr. Aya M. Serry2015/2016

Definition:

Pneumonia is an inflammation of the lungs caused by infection

Bacteria, viruses, fungi or parasites can cause pneumonia

Pneumonia is a particular concern if you're older than 65 or have a chronic illness or weak immune system

It can also occur in young, healthy people

Pneumonia

Types of pneumonia:

1. Community-acquired pneumonia 

When you get pneumonia from contact with germs in your normal routine, it's called community-acquired pneumonia

It is a mild form of pneumonia that doctors can treat without difficulty

The microbes responsible for most community-acquired pneumonia are:

Pneumonia

A. Bacteria. The bacterium that causes most cases of community-acquired pneumonia is Streptococcus pneumoniae. Other possible agents include Staphylococcus aureus and Haemophilus influenzae

B. Bacteria-like organisms. Mycoplasma pneumoniae ; produces milder signs and symptoms than other types of pneumonia.

• Walking pneumonia, a term used to describe pneumonia that isn't severe enough to require bed rest, may result from Mycoplasma pneumoniae.

Pneumonia

C. Viruses. Some of the same types of viruses that cause the flu and colds can also cause pneumonia.

• viral pneumonia caused by influenza viruses can become very serious.

D. Fungi and parasites. Other less-common causes of community-acquired pneumonia include fungi, parasites and the germ that causes tuberculosis.

• Most cases of parasitic pneumonia occur in people who live or have traveled in developing countries.

Pneumonia

Types of pneumonia:

2. Hospital-acquired pneumonia 

occurs during a hospital stay. This type of pneumonia can be very severe. Sometimes it can be fatal.

Hospital-acquired pneumonia tends to be more serious than other lung infections because:

• Patients in the hospital are often very sick and cannot fight off germs

• The types of germs present in a hospital are often more dangerous than those encountered in the community

Hospital-acquired pneumonia occurs more often in patients who are using a respirator machine (ventilator) to help them breathe.

Pneumonia

Types of pneumonia:

3. Inhalation or aspiration pneumonia 

• Aspiration pneumonia occurs when you breathe foreign matter into your lungs. This can happen if you vomit while asleep or unconscious and breathe in some of the contents of the stomach

• Parkinson's disease and strokes, occasionally leads to aspiration pneumonia.

Types of Pneumonia

Types of pneumonia:

4. Opportunistic viral, bacterial and fungal pneumonias

• These types of pneumonia strike people with weakened immune systems.

• Organisms that aren't harmful for healthy people can be dangerous for people who have had an organ transplant and people with AIDS and other conditions that impair the immune system.

• Medications that suppress your immune system, such as corticosteroids or chemotherapy, also can put you at risk of opportunistic pneumonia.

Types of Pneumonia

Symptoms:

Pneumonia often mimics the flu, beginning with a cough and a fever, so you may not realize you have a more serious condition. Symptoms can vary depending on your age and general health. These signs include:

• Fever• Cough

• Shortness of breath• Sweating

• Shaking chills• Chest pain

• Headache

• Fatigue

Symptoms of Pneumonia

Pathophysiology and complications:Pneumonia is more likely to cause complications in older people, smokers and people with heart failure or lung disease. Pneumonia complications may include:

Bacteria in your bloodstream. 

• In pneumonia, alveoli contain bacteria that may enter the bloodstream during gas exchange. Infection then spreads through the bloodstream, potentially causing shock and failure of multiple organs.

Septic shock. 

• Unchecked bacterial growth in the bloodstream can shut down normal circulation. Blood fills the veins and leaks through the walls of the capillaries, causing uncontrolled tissue swelling and possibly organ failure, which can lead to death.

Pneumonia Complications

Pathophysiology and complications: Fluid accumulation and infection around your lungs.

•  Sometimes fluid accumulates between the thin, transparent membrane (pleura) covering your lungs and the membrane that lines the inner surface of your chest wall - a condition known as pleural effusion.

Lung abscess. 

• Occasionally a cavity containing pus (abscess) forms within the area affected by pneumonia.

Acute respiratory distress syndrome (ARDS).

•  When pneumonia involves most areas of both lungs, breathing is difficult and your body doesn't get enough oxygen.

Pneumonia Complications

Risk Factors:Age. If you're age 65 or older and Very young children, whose immune

systems aren't fully developed

Certain diseases. These include:

• immune deficiency diseases such as HIV/AIDS• chronic illnesses such as heart disease• lung diseases.• if your immune system has been weakened by chemotherapy or long-term

use of immunosuppressant drugs

Smoking 

Exposure to certain chemicals or pollutants. Exposure to air pollution or toxic fumes can also contribute to lung inflammation

Pneumonia Risk Factors

Tests and Diagnosis• Your doctor may first suspect pneumonia based on your medical history

and a physical exam.

Physical exam. During the exam, your doctor listens to your lungs sounds that signal the presence of thick liquids

Pneumonia diagnosis

Tests and Diagnosis Chest X-rays. 

Blood and mucus tests. to measure your white cell count and look for the presence of viruses, bacteria or other organisms.

Normal Chest X-ray Pneumonia X-ray

Pneumonia diagnosis

Medications and Treatment

Antibiotics are used to treat bacterial pneumonia. Other medications may help improve breathing and relieve symptoms in bacterial and viral pneumonia.

Medication options include:

Antibiotics. Antibiotics are not effective for treating viral pneumonia.

Antivirals.

Fever reducers. 

Cough medicine. 

Pneumonia Treatments

Lifestyle and Home Remedies

If you have pneumonia, the following measures can help you recover more quickly and decrease your risk of complications:

Get plenty of rest. 

Stay home from school or work until after your temperature returns to normal and you stop coughing up mucus.

Drink plenty of fluids, especially water. Liquids keep you from becoming dehydrated and help loosen mucus in your lungs.

Take the entire course of any prescribed medications. 

Keep all of your follow-up appointments. 

Pneumonia Management