Pneumonia

By Lori Hansen, MD, FACP, Board Certified Pulmonologist, Yankton Medical Clinic, P.C.

Pneumonia causes more than 60,000 deaths in America each year, and is the leading cause of death in children worldwide. Pneumonia is an infection of the lungs that’s caused by infection with bacteria, viruses, fungi or other organisms.  Pneumonia should be a concern for older adults and people with chronic illnesses or impaired immune systems, but it can also strike young, healthy people. 

There are numerous types of pneumonia ranging from mild to life-threatening. Symptoms of pneumonia can vary, but may include cough, shortness of breath, chest pain, fever, and chills. Pneumonia often follows a cold or the flu, but can also be associated with other illnesses or occur on its own.

Pneumonia can have over 30 different causes. The five main causes are:

• Bacteria. Many types of bacteria can cause pneumonia. Bacterial pneumonia can occur on its own, at the same time as a viral pneumonia, or after you’ve had a viral upper respiratory infection such as influenza or a cold. Symptoms can vary from gradual to sudden and include shaking chills, a high fever, sweating, shortness of breath, chest pain, and a cough that produces thick, greenish or yellow phlegm. Bacterial pneumonia is treated with antibiotics.
• Viruses. It is believed that about 50% of all pneumonia is caused by viruses. Viral pneumonia usually begins with flu-like symptoms- a dry cough, headache, fever, muscle pain and weakness. As it worsens, you may become breathless and develop a cough that produces small quantities of clear or white phlegm. With viral pneumonia, you run the risk of also developing a bacterial pneumonia. Antibiotics aren’t effective against most viral pneumonias. Rest and plenty of fluid is important.
• Mycoplasma. This tiny organism causes symptoms similar to those of other bacterial and viral infections, although symptoms appear more gradually and are often mild and flu-like. You may not be sick enough to even know you’ve had pneumonia- this type of pneumonia is often called walking pneumonia. Mycoplasma pneumonia spreads easily where people congregate and is common among young adults. Mycoplasma pneumonia is treated with antibiotics.
• Fungi. Although uncommon, certain types of fungus can also cause pneumonia. Most people experience few if any symptoms after inhaling these fungi, but some develop symptoms of mild pneumonia, and still others may develop a pneumonia that persists for months. Treatment is antifungal medication.
• Pneumocystis carinii.  Pneumonia caused by P. carinii is an infection that affects people whose immune systems are compromised by AIDS, organ transplants, chemotherapy, or treatment with corticosteroids or other immune-suppressing drugs. The symptoms of Pneumocystis carinii pneumonia include a cough that doesn’t go away, fever and shortness of breath. Treatment is antibiotics.

Your lungs are made up by billions of air sacs or alveoli. The lungs are surrounded by the pleura. Each lung is divided into lobes-three on the right and two on the left. When you inhale, air is carried through the windpipe (trachea) to the bronchial tubes to the alveoli. The exchange of oxygen occurs in the alveoli.

White blood cells (leukocytes) assist your immune system by attacking the invading organisms. The accumulating pathogens, white cells and immune proteins cause the air sacs to become inflamed and filled with fluid, leading to difficulty in breathing that many people experience with pneumonia.

You are frequently exposed to bacteria and viruses that can cause pneumonia, but your body has mechanisms to protect your lungs from infection. For unknown reasons, microorganisms can get past your body's defenses, and find their way into your lungs' air sacs.

Pneumonia is classified according to the cause of the pneumonia, and each has a different treatment plan.

Community-acquired pneumonia. This refers to pneumonia you acquire in the course of your daily life. 

Hospital-acquired (nosocomial) pneumonia. Hospitalization places you at a higher risk of developing pneumonia, especially if you are on a mechanical ventilator, are in the intensive care unit or have a compromised immune system. This type of pneumonia can be very serious, especially for older adults, young children and people with chronic disease.
Aspiration pneumonia.

This type of pneumonia occurs when foreign matter is inhaled (aspirated) into your lungs - most often when the contents of your stomach enter your lungs after you vomit. This commonly happens when a brain injury, or other condition causing unconsciousness, affects your normal gag reflex.  Consuming too much alcohol is another common cause of aspiration pneumonia. This happens when the inebriated person passes out, and then vomits due to the effects of alcohol.

Pneumonia caused by opportunistic organisms. This type of pneumonia strikes people with compromised immune systems. Organisms that aren't harmful for healthy people can be extremely dangerous for people with AIDS, organ transplantation and other conditions that impair the immune system. Medications that suppress your immune system, such as corticosteroids or chemotherapy can also put you at risk of opportunistic pneumonia.

Emerging pathogens. Outbreaks of the H5N1 influenza (bird flu) virus and severe acute respiratory syndrome (SARS) have caused serious and sometimes deadly pneumonia infections. Methicillin resistant staphylococcus aureus (MRSA) infections are emerging in hospitals and are difficult to treat.

Adults 65 years and older, very young children, and those who are compromised are at increased risk of pneumonia. You're also more likely to develop pneumonia if you: smoke, are exposed to chemicals or pollutants, or abuse alcohol.

Don't hesitate to get medical care if you think you may have pneumonia. See your physician immediately if you have a persistent cough, shortness of breath, chest pain that fluctuates with your breathing (pleurisy), an unexplained fever - especially a persistent fever of 102 F or higher along with chills and sweats - or if you suddenly feel worse after a cold or the flu.

In addition to these treatments, your physician may recommend over-the-counter medications to reduce fever. When using a cough suppressant, use the lowest dose that helps you get some rest, because coughing helps clear your lungs.

If you have severe pneumonia, you'll be hospitalized and treated with antibiotics intravenously and put on oxygen.

Your physician will most likely schedule a follow-up X-ray and an office visit after your initial diagnosis and treatment of pneumonia. Follow-up appointments and X-rays are especially important in smokers. If you're not feeling better, the follow-up visit is an opportunity for your doctor to schedule tests to determine more specifically what is causing your symptoms.

The following suggestions can help keep you healthy:

• Get vaccinated. Because pneumonia can be a complication of the flu, getting a yearly flu shot is a good way to prevent viral influenza pneumonia, which can lead to bacterial pneumonia. In addition, get a vaccination against pneumococcal pneumonia if you are older than 65 or have underlying health problems.
• Wash your hands.
• Don't smoke.
• Take care of yourself.
• Protect others from infection.

It is important to remember that even though pneumonia can be treated, it is a serious illness.  Don’t wait-get treatment early.