Pneumonia is an inflammation of one or both lungs. Many types of pneumonia have been distinguished, but usually when the word pneumonia is used without qualification, lobar pneumonia, in which one or more entire lobes are infected, is implied, and the causative organism is the pneumococcus. Other organisms may also produce pneumonia, such as the streptococcus and staphylococcus, which may cause bronchopneumonia.

Pneumonia is the 5th leading cause of death in the elderly since this can go unrecognized as they may be asymptomatic due to other medical issues or typical age-related changes in the lungs like decreased productive cough for bringing up liquid/sputum from the lungs.

The symptoms of a typical case of pneumonia may follow a slight cold or infectious disease or may appear suddenly without warning. A shaking chill may be followed by a sharp stabbing pain on the side of or in the chest, with coughing and expectoration of brown or bloody sputum. The pulse is rapid, the cheeks flushed, temperature rises sharply, and weakness and even prostration, headache, nausea, vomiting, and diarrhea sometimes ensue.

The person with pneumonia must be put to bed immediately, and carefully watched, since restlessness, sleeplessness, and even delirium may provoke the patient, despite his weakness, to try to get out of bed.

As the infection progresses, changes may take place in the lung itself. It may become filled with inflammatory material and solidify, causing shortness of breath and shallow noisy breathing. The blood cannot obtain sufficient oxygen and so the skin and mucous membranes may become bluish, a condition known as cyanosis. The patient must be placed in an oxygen tent to assist his breathing as well as correct the cyanosis.

During the acute stages of pneumonia, care must be taken to prevent complications, such as heart failure, empyema, distention of the abdomen, and abcess. The development of other diseases, including pericarditis, endocarditis, meningitis, and arthritis, must also be carefully prevented.

For long time pneumonia was a dreaded disease with a high mortality rate. Treatment depended on the use of serums, which were developed to combat specific infections, and the condition usually led to an acute stage with a definite crisis, in which the patient appeared near collapse. After the crisis, a sharp drop in temperature followed and the patient fell into a deep sleep, with subsequent recovery in some cases.

Today the use of sulfonamides and antibiotics, such as penicillin, terramycin, aureomycin, and streptomycin, have decreased the development of lung abscess and empyema, and the death rate has fallen sharply. Good nursing care in pneumonia still continues to play a considerable part. The recovery period is especially significant. The patient should not get up from bed or engage in activity too early. A complete physical checkup, including a chest x-ray examination, is strongly advised following pneumonia.

The number of cases of virus pneumonia has sharply increased, at the same time that bacterial pneumonia has yielded to treatment with sulfa drugs and antibiotics. Although the nature of viruses is not completely understood, and few specific measures have been developed to combat them, it is known that virus pneumonia is produced by a number of specific types of virus. Virus pneumonia may vary from mild or walking state to a serious condition requiring hospitalization. In a mild case the patient may not suspect that he has anything more severe than a slight cough and fever, which may ascribe to a cold. In the more severe form, fever, sweating, malaise, headache, sore throat, weakness, and a dry hacking cough are involved.

Treatment of virus pneumonia includes bed rest, even in a mild case. Antibiotics are frequently effective in preventing complications. It is essential to treat the fever and cough; and in severe cases in which cyanosis is present; an oxygen tent may also be required. In general, virus pneumonia does not persist more than a few days to a week. However, convalescence, usually characterized by weakness, is often long and slow, and x-ray examination of the chest may reveal shadows for several weeks. These information were taken from The New Illustrated Medical and Health Encyclopedia.