Clinical pneumonia is a way to classify pneumonia based on both how long a person has had pneumonia and how he or she contracted the disease. As there are many biological and non-biological causes of pneumonia, this classification system is essential so a patient can begin treatment as soon as possible. After designating a pneumonia as acute or chronic, a doctor determines whether it is community-acquired or hospital-acquired. As a pneumonia's cause can fall outside out of these choices, the problem of misdiagnoses is growing.
The issue with diagnosing pneumonia is that the condition itself, inflammation of lung tissue and the lungs filling with fluid, can be caused by parasites, fungi, bacteria or environmental conditions such as dust. As pneumonia can quickly become life threatening, it is necessary for doctors to systematically approach diagnosing the root cause. Examining the clinical characteristics, how and when the pneumonia presents, allows a doctor to diagnose clinical pneumonia. For example, if the clinical diagnosis reveals that a patient's pneumonia is most likely caused by a bacterium, the patient is given broad spectrum antibiotics. If the antibiotics are ineffective, a doctor must rework his or her clinical diagnosis.
The first step a doctor makes in diagnosing clinical pneumonia is determining whether the pneumonia is acute or chronic. A patient with acute pneumonia developed the condition within three weeks before visiting his or her doctor. Chronic pneumonia is a condition that has lasted a longer period of time. The distinction is important, because if a doctor can determine whether a pneumonia is acute or chronic, he or she can significantly narrow the list of possible causes. Before treatment can begin, it is still necessary to know where the patient acquired pneumonia.
Community-acquired and hospital-acquired clinical pneumonia are the two choices a doctor considers before treating his or her patient. Community-acquired narrows the list of causes to certain sets of bacteria and viruses. It is the most common type. Hospital-acquired is only considered if the patient was recently in the hospital or if the pneumonia developed during a hospital stay. A group of bacteria including MRSA causes hospital-acquired clinical pneumonia.
Though clinically diagnosing pneumonia generally allows treatment to begin earlier and saves more lives, misdiagnosis of clinical pneumonia caused by a chemical or non-biological factor is a real possibility. Heavy dust and some aerosol chemicals create the same set of symptoms as viral or bacterial pneumonia. A patient may receive the wrong treatment while his or her condition worsens. Also, the rise of new pneumonia-causing viruses such as SARS are making doctors reconsider the overall effectiveness of the clinical diagnosis.