The clinical state of the person at time of presentation is a vital predictor of the clinical course. On the basis of the severity of symptoms, underlying disease and age, many clinicians use Pneumonia Severity Score to evaluate if a patient requires hospital admission. In the United States, death from pneumococcal pneumonia is 1 in 20; in cases where the disease progresses to blood poisoning, bacteremia, 2 of 10 die and where the disease affects the brain, meningitis, 3 of 10 die.
Prognosis of pneumonia caused by Chlamydophila pneumonia is excellent. Hospitalization is uncommon, complications are rare, and most people have no residual deficits. In fact, Chlamydophila pneumoniae is a common cause of walking pneumonia, so named because most people are able to continue to walk and participate in reduced activity during infection.
Approximately 1.2 million people are hospitalized every year for pneumonia, which is the 3rd most prominent reason for hospitalizations (births and heart diseases are first and second, respectively). Even though majority of pneumonias respond well to treatment, the infections can still pose a very serious problem. Together with flu, pneumonia is the 6th leading cause for death in the US and is the leading cause for death from infection.
Hospitalized Patients For people who require hospitalization for pneumonia, the mortality rate is between 10% and 25%. If pneumonia develops in people already hospitalized for other conditions, the mortality rates are higher. They range from 50% to 70% and are greater in women than in men.
Older Adults Community-acquired pneumonias are responsible for ~350,000 to 620,000 hospitalizations in older adults every year. The elderly have less survival rates than younger people, and pneumonia and flu are the 5th major causes of death in this population. Even when older people recover from community-acquired pneumonia, they have higher than normal mortality rates over the next few years. Older adults at particular risk are those with some other medical problems and hospitalized patients.
Very Young Children About 20% of deaths in stillborn and very young infants are because of pneumonia. Little children who develop pneumonia and survive are at also at risk for developing lung problems in adulthood.
Pregnant Women Pneumonias pose a significant hazard for pregnant women.
Patients With Impaired Immune Systems Pneumonia is particularly serious in patients with compromised immune systems, particularly AIDS patients, in whom pneumonia causes about half of all deaths.
Patients With Serious Medical Conditions Pneumonia is also very dangerous in patients with diabetes, cirrhosis, sickle cell disease, cancer, and in those who have had their spleens removed.