By Aparna Mani, MD, PhD
MGH Medical Walk-In Unit

Pneumonia is a disease that has been described since the time of Hippocrates.  Though the ancient Greeks accurately identified the symptoms that constitute pneumonia, it wasn’t until the mid-1800’s that a scientist named Edwin Klebs observed bacteria in the lungs of people who had died of pneumonia, pointing to infection as a major cause of this illness.  Simply put, pneumonia is an inflammation of the lungs most commonly caused by infection.  It affects more than five million people in the United States and an estimated 450 million people worldwide each year, thus the World Health Organization has designated November 12^th as World Pneumonia Day.

The lungs are composed of airways that bring in oxygen and alveoli (microscopic air sacs) that help deliver it to the bloodstream. The lungs have several defenses to protect against invading bacteria, viruses and other types of microorganisms.  These include mucus producing goblet cells and tiny hair-like projections called cilia—not to mention the body’s own immune system.  Sometimes these defenses may be overwhelmed or breached, allowing a particular microorganism to take hold and fester in the alveoli. The result is a local pool of infection that fills and plugs up the alveolus, much like pus in a skin wound. The sheer volume of infection makes it hard for immune cells to get in and do their job of breaking it down and clearing it out.  A person suffering from pneumonia may experience fever, shaking chills, fatigue, productive cough, chest pain and shortness of breath.  Contact your healthcare provider if you are experiencing any of these symptoms.

To diagnose pneumonia, healthcare providers rely on history of symptoms and a lung exam which includes listening to breathing sounds through a stethoscope and percussing the lungs (a special technique of tapping the chest) with their hands.  A chest x-ray may also be done, though it is not always necessary. The main treatment for bacterial pneumonia is antibiotics.  Providers often base their treatment on the most commonly known microorganism given age, risk factors and living environment, though mucus or sputum samples may also be obtained to identify the specific bacteria causing the pneumonia. This allows providers to better pinpoint the appropriate drug to use in treatment. Depending on the severity of symptoms and other risk factors such as age and overall health, healthcare providers may choose to treat an individual as an outpatient or admit them to the hospital.  With treatment a patient may stabilize and begin to improve within a few days, but it may take a few weeks before symptoms resolve completely.

Risk factors such as smoking, excessive alcohol use, immunodeficiency, and chronic illnesses such as COPD, kidney disease and diabetes can increase an individual’s susceptibility for developing pneumonia. Seniors (people 65 and older) and young children are also at increased risk.  The pneumococcal vaccine developed against bacteria commonly known to cause pneumonia is recommended for seniors and anyone with the above risk factors. Talk to your healthcare provider about whether vaccination is indicated for you. In addition to vaccination, pneumonia can be prevented with everyday good hygiene practices such as hand washing, coughing or sneezing into an elbow or sleeve, and taking care of one’s overall health– including keeping blood sugar in good control.