Subject | Contents |
Definition | Pneumonia is an inflammation of the lungs caused by a bacterial, viral, or fungal infection. |
Alternative Names | Pneumonitis; Bronchopneumonia; Community-acquired pneumonia
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Causes, incidence, and risk factors | Pneumonia is a very common, often serious illness that affects about 3-4 million people each year in the United States. Many different organisms can cause pneumonia, including bacteria, viruses, and fungi. Bacterial pneumonias tend to be the most serious. In adults, bacteria are the most common cause, and of these Streptococcus pneumoniae (pneumococcus) is the most common. Respiratory viruses are the most common causes of pneumonia in young children, peaking between the ages of 2 and 3. By school age, the bacterium Mycoplasma pneumoniae becomes more common. In some people, particularly the elderly and those who are debilitated, pneumonia may follow influenza . Pneumonia is classified according to a number of different systems. One classification system divides pneumonia into "community-acquired" (pneumonia contracted outside of a health-care institution) and "hospital-acquired" (acquired in a hospital or other long-term health care facility). S. pneumoniae is the most common form of community-acquired pneumonia. Hospital-acquired pneumonia tends to be more serious because the patient's defense mechanisms against infection are often impaired when someone is hospitalized, due to the condition that initially required treatment . In addition, there is a greater possibility of infection with bacteria that are resistant to antibiotics. Other classifications of pneumonia include:aspiration pneumoniaatypical pneumonia bacterial pneumonia CMV pneumonia hospital-acquired pneumonia Legionella pneumonia Mycoplasma pneumonia ( walking pneumonia )necrotizing pneumonia pediatric pneumonia Pneumocystis carinii pneumonia pneumonia in immunocompromised hostpneumonia with lung abscesspyogenic pneumoniaviral pneumonia |
Symptoms | cough with mucus-like, greenish, or pus-like sputum chills with shaking fevereasy fatiguechest pain sharp or stabbing increased by deep breathing increased by coughingheadacheloss of appetitenausea and vomiting general discomfort, uneasiness, or ill feeling ( malaise ) joint stiffness (rare) muscular stiffness (rare) Additional symptoms that may be associated with this disease: shortness of breath excessive sweating clammy skin nasal flaringcoughing up blood rapid breathing anxiety, stress, and tensionabdominal pain |
Signs and tests | Crackles are heard when listening to the chest with a stethoscope ( auscultation ). Other abnormal breathing sounds may also be heard. Tests include: chest X-ray Gram's stain and culture of the sputum CBCarterial blood gases This disease may also alter the results of the following tests: thoracic CTroutine sputum culturepulmonary ventilation/perfusion scanpleural fluid culturelung needle biopsy |
Treatment | If the cause is bacterial, the goal of treatment is to cure the infection with antibiotics. However, if the pneumonia is caused by a virus, antibiotics will NOT be effective. Supportive therapy includes oxygen and respiratory treatments to remove secretions, if needed. |
Support Groups | |
Expectations (prognosis) | Most patients will respond to treatment and improve within two weeks. Elderly or debilitated patients who fail to respond to treatment may die from respiratory failure. |
Complications | acuterespiratory failure death empyema |
Calling your health care provider | Call your health care provider if symptoms suggesting pneumonia develop. |
Prevention | Vaccination can help prevent some types of pneumonia in children and at-risk adults (such as the elderly). These include:pneumococcal vaccine (Pneumovax (R) (prevents pneumonia caused by Streptococcus pneumoniae )flu vaccineHib vaccine (prevents pneumonia from Haemophilus influenzae type b) Coughing and deep breathing may help prevent some forms of hospital-acquired pneumonia . See also the prevention steps listed under specific types of pneumonia. |
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