Pneumonia - Prognosis

Highlights	Risk Factors	Prevention
Introduction	Diagnosis	Resources
Causes	Treatment	References
Symptoms	Medications
Prognosis	Surgery

Prognosis

More than a million people are hospitalized each year for pneumonia, making it the third most frequent reason for hospitalizations (births are first and heart disease is second). Although the majority of pneumonias respond well to treatment, the infection can still be a very serious problem. It kills between 40,000 and 70,000 people each year.

Outlook for High-Risk Individuals

Hospitalized Patients. For patients who require hospitalization for pneumonia, thedeath rate is between 10 - 25%. If pneumonia develops in patients already hospitalized for other conditions, therates areeven higher. They range from 50 - 70% and are greater in women than in men.

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Older Adults. Community-acquired pneumonia is responsible for 350,000 to 620,000 hospitalizations in the elderlyevery year.Older adultshave lower survival rates than younger people.Even when older individuals recover from community-acquired pneumonia, they have higher than normaldeath rates over the next several years. Elderly people who live in a nursing home or who are already sick are at particular risk.

Very Young Children. About 20% of deaths in stillborn and very young infants are due to pneumonia. Small children who develop pneumonia and survive are at also at risk for developing lung problems in adulthood.

Pregnant Women. Pneumonia poses a special hazard for pregnant women, possibly due to changes in a pregnant woman's immune system. It is a leading cause of a mother's death.

Patients With Impaired Immune Systems. Pneumonia is particularly serious in people with impaired immune systems. This isparticularly true for AIDS patients, in whom pneumonia causes about half of all deaths.

Patients With Serious Medical Conditions. Pneumonia is also very dangerous in people with diabetes, cirrhosis, sickle cell disease, cancer, and in those who have had their spleens removed.

Risk by Organisms

Specific organisms vary in their effects. Mild pneumonia is usually associated with the atypical organisms Mycoplasma and Chlamydia. Severe pneumonia is most often associated with a wide range of organisms. Some are very virulent (potent) but are extremely curable, while others are difficult to treat.

Mycoplasma and Chlamydia are the most common causes of mild pneumonias and are most likely to occur in children and young adults. They rarely require hospitalization when they are appropriately treated, although recovery may still be prolonged. Severe and life-threatening cases are more likely to occur in elderly people with other medication conditions.
S. Pneumonia is the most common cause of pneumonia and, in fact, all upper respiratory infections. It can produce severe pneumonia, with mortality rates of 10%. Nevertheless, it is very responsive to many antibiotics.
Staphylococcus aureus is a gram-positive bacterium that often causes severe pneumonia in hospitalized patients and following influenza A and B in high-risk patients. People who get this form of pneumonia may develop pockets of infection in their lungs (abscesses) that are difficult to treat and can cause death of lung tissue(necrosis). Mortality rates are30% to 40%, in part because the patients who develop this infection are generally very ill or vulnerable.
Pseudomonas aeruginosa and Klebsiella pneumonia are gram-negative bacteria that pose a risk for abscesses and severe lung tissue damage.
Legionella pneumophila is very virulent and can cause widespread damage. Treatments have improved dramatically since it was first identified. However, a 2002 study suggested that many patients experience long-term problems, including coughing, shortness of breath, fatigue and neurological and muscular complications.
Viral pneumonia is usually very mild, but there are exceptions. Pneumonia associated with influenza can be serious. Respiratory syncytial virus (RSV) pneumonia rarely poses a danger for healthy young adults, but can be life threatening in infants and serious in the elderly.