Chest | Pulmonology | Pneumonia (Disease)


Pneumonia is an infection of one or both lungs which is usually caused by bacteria, viruses, or fungi. Prior to the discovery of antibiotics, one-third of all people who developed pneumonia subsequently died from the infection.

People with infectious pneumonia often have a productive cough, fever accompanied by shaking chills, shortness of breath, sharp or stabbing chest pain during deep breaths, confusion, and an increased respiratory rate. In the elderly, confusion may be the most prominent symptom.

Causes and Risk factors

Some cases of pneumonia are contracted by breathing in small droplets that contain the organisms that can cause pneumonia. These droplets get into the air when a person infected with these germs coughs or sneezes.

In other cases, pneumonia is caused when bacteria or viruses that are normally present in the mouth, throat, or nose inadvertently enter the lung. During sleep, it is quite common for people to aspirate secretions from the mouth, throat, or nose. Normally, the bodys reflex response (coughing back up the secretions) and their immune system will prevent the aspirated organisms from causing pneumonia. However, if a person is in a weakened condition from another illness, a severe pneumonia can develop.

People with recent viral infections, lung disease, heart disease, and swallowing problems, as well as alcoholics, drug users, and those who have suffered a stroke or seizure are at higher risk for developing pneumonia than the general population.

Diagnosis and Risk factors

An X-ray can confirm the diagnosis. Blood tests, sputum cultures, and blood cultures can identify the cause and severity of the infection. Occasionally a CT scan is performed as well especially if an associated pleural effusion is present.

Antibiotics are only effective for bacteria but many times the cause of the pneumonia cannot be determined resulting in most patients initially receiving antibiotics (azithromycin, clarithromycin, erythromycin, levofloxacin, ceftriaxone). If the pneumonia is severe admission to the hospital and intravenous antibiotics will be administered. Severe cases can require mechanical ventilation.