Experts have finally reached a consensus on managing community-acquired pneumonia. Here’s a summary of the new recommendations.
Though community-acquired pneumonia (CAP) is commonly seen in primary-care practices, there has been confusion about the standards of treatment. Over the years, a number of sometimes conflicting guidelines were developed by organizations in related specialties. Recently, however, the Infectious Diseases Society of America (IDSA) and the American Thoracic Society (ATS) joined forces to develop the new Consensus Guidelines on the Management of Community-Acquired Pneumonia in Adults.
“The perception was that the various guidelines contained different standards of care for CAP,” says Thomas M. File Jr, MD, professor of internal medicine and director of the Infectious Disease Section at Northeastern Ohio University College of Medicine in Rootstown. “With one unified, collaborative statement, we can now avoid any potential confusion.” The new Guidelines provide primary-care clinicians with an authoritative statement of practice standards for diagnosing and treating CAP.
High incidence among the elderlyPneumonia and influenza combined were the seventh-leading causes of death in the United States in 2001, the latest year studied. The estimated age-adjusted death rate is 21.8 per 100,000 population. Approximately 4 million to 5 million cases of CAP are diagnosed each year, and about 25% of these result in hospitalizations. CAP is more common among older people, with an incidence rate of 280 cases per 10,000 individuals older than 65 years of age. Death rates increase among the elderly and individuals with comorbidities. CAP affects both sexes and all races equally.Some people may be at greater risk for developing pneumonia, including those who:
• Are aged 65 and older
• Smoke cigarettes
• Are malnourished
• Have lung disease (e.g., asthma, cystic fibrosis, and chronic obstructive pulmonary disease)
• Have other chronic conditions, such as heart disease anddiabetes
• Have a weakened immune system due to chemotherapy, organ transplant, HIV, or chronic steroid use
• Recently had a viral upper respiratory infection.
Since most of the major decisions involved in the treatment of CAP are based on its severity, an accurate diagnosis is imperative. However, reaching a definitive answer can be challenging since pneumonia may be caused by various agents for which symptoms frequently overlap. Additionally, it can often be difficult to distinguish pneumonia from bronchitis, influenza, and other lower respiratory infections caused by viruses.
Antibiotic resistance complicates patient treatment options. Bacteria resistant to antibiotics spread infections with new strains that are more difficult for clinicians to treat. Research suggests that the use of antibiotics for individuals with viral illnesses is disturbingly persistent, leading to continued spread of bacterial resistance. This underscores the importance of reaching an accurate diagnosis of CAP before prescribing antibiotics.
The site-of-care and the type of medication to be prescribed involve a careful review of the symptoms, a medical history, a physical examination, and chest x-rays.
Common symptoms of CAP include cough, fever, chills, fatigue, shortness of breath, difficulty in breathing, chills, and chest pain. The diagnosis may be confused with bronchitis or other lower respiratory infections, which also exhibit these symptoms. Comorbid conditions, which are more frequent among very young children or elderly patients, also complicate the diagnosis.
A thorough medical history goes beyond the symptoms to investigate current medications (including all prescription, OTC, and herbal substances), past and present medical conditions, and whether the patient is a smoker. The clinician should ask if the patient has received flu or pneumonia vaccines and determine if he or she has been exposed to sick people at home, school, or work.
“Each community has its own unique susceptibility patterns,” says Dr. File. “Different organisms are present in various geographic regions, and areas have their own diverse patterns of resistance to medications. You should be informed about which organisms are most prevalent in your community.” While there may be various “bugs going around,” the clinician cannot assume that each patient is infected with the same pathogen.
“Another question is often neglected when clinicians take the medical history,” continues Dr. File. “Ask if the patient has been traveling recently and if so, to what locations. Organisms that are prevalent in some parts of the world are not always present in this country. Also, find out if the patient has been on a farm or in a setting with animals. The answers could provide an important clue in determining the type of infection that is causing the pneumonia.”
A complete physical examination focuses special attention on the patient’s heart and lungs. Rales heard through the stethoscope may signify pneumonia, and further testing may be warranted.
“The most important test for pneumonia is a chest x-ray,” says Dr. File. “Not only does the x-ray help to correctly establish the diagnosis, it lets the clinician determine the severity of the disease. You also can establish whether pneumonia is present in one or both lungs. This information allows you to determine whether antibiotics are justified and which agents are most appropriate.”Other tests may be used if additional information is needed, including pretreatment blood samples for culture, Gram stain, culture of sputum, and antigen tests for Legionella pneumophila and Streptococcus pneumoniae in severe CAP.
The site-of-care decision is based on the severity of the pneumonia and its prognosis. Many patients who could be managed on an outpatient basis and would prefer to recuperate at home are unnecessarily admitted to the hospital. Clinicians can use one of two widely available scales to rate the severity of the illness and determine whether hospitalization is required. Additionally, the patient’s ability to take oral medication and the availability of a supportive home environment must also be considered.
The rating scale most familiar to clinicians is the Pneumonia Severity Index (PSI), which contains 20 characteristics calculated in points that measure five levels of risk, which can suggest whether treatment should be outpatient or inpatient.
“The PSI has been validated and is considered very reliable,” says Dr. File. “However, the newer CURB-65 scale may be easier to use.” The criteria included in CURB-65 are: Confusion, Uremia, Respiratory rate, low BP, age 65 or older.
Patients with low PSI or CURB-65 scores who have no comorbidities or low-risk comorbidities may be treated on an outpatient basis. Patients with higher scores may need more intensive treatment, including hospitalization. If hospitalization is required, clinicians may need to determine whether to place patients in an ICU.
Treatment with antibiotics
The selection of the most appropriate medication depends on the pathogen causing the CAP and whether it is resistant to antibiotics. Clinicians also need to consider each patient’s risk factors and comorbidities in choosing treatment.
A wide range of antibiotics have been approved by the FDA for CAP. The new Guidelines generally recommend a class of antibiotics rather than a single drug. In some cases, however, outcome data clearly indicate a specific drug. Table 1 has a brief synopsis of the recommended empiric antibiotics. Clinicians are advised to consult the full listing, which includes additional qualifications and exceptions (. Accessed May 9, 2008).
Recent research has focused on how soon the first dose of antibiotics should be administered for CAP. Retrospective studies of Medicare patients suggest that those who receive early antibiotic therapy may experience lower mortality. Based on these findings, many hospitals have established the so-called four-hour rule, which mandates that patients with CAP should receive antibiotics within four hours after admission. Some clinicians believe that this is a generalization which may be misleading because it does not take into consideration the possibilities of diagnostic uncertainties or other potentially complicating situations. While there appears to be an association between early treatment with antibiotics and length of hospital stay, research indicates that the time to clinical stability is not reduced. The Guidelines do not recommend a specific time for the first treatment but do advise that therapy be given as soon as an accurate diagnosis can be made.
Patients with CAP who are receiving IV antibiotic therapy in the hospital generally show improvement in about three days, according to the Guidelines. As soon as they are able to take oral medications and their GI tract is normal, they should be switched from IV to oral antibiotics. They may be discharged from the hospital as soon as they are clinically stable, have no other medical problems, and have a suitable environment for recuperation.
The Guidelines also indicate that patients with CAP should be treated for at least five days; before treatment is discontinued, patients should be clinically stable and free of fever for 48- 72 hours. Therapy may be required for a longer period if the patient fails to respond to initial treatment or if there are other comorbidities, such as cancer and heart disease.
The primary method for preventing CAP is inoculation with the pneumococcal vaccine. All older adults and others who have medical conditions that place them at high risk should receive it. A survey in 2003 revealed that only 69% of adults 65 years of age and older had received the flu vaccine and even fewer, 64%, had ever received the pneumonia vaccine. Better compliance with use of these vaccines could be effective in reducing the incidence of CAP.
The Guidelines for CAP were published in Clinical Infectious Diseases (2007:44 Suppl 2:S27-S72) and are available online at: www.journals.uchicago.edu (accessed May 9, 2008). Additionally, PDA files with links for easy browsing can be downloaded at: www.idsociety.org (accessed May 9, 2008).
Ms. Saul is a medical writer in Chicago.
- UpToDate. Patient information: pneumonia in adults. Available at www.uptodate.com/patients/content/topic.do?topicKey=inf_immu/2402. Accessed May 9, 2008.
- CDC. About antibiotic resistance. Available at www.cdc.gov /drugresistance/community/antibiotic-resistance.htm.
- Emedicine. Pneumonia, community-acquired. Available at www.emedicine.com/med/topic3162.htm. Accessed May 9, 2008.
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- Lutfiyya MN, Henley E, Chang LF, Reyburn SW. Diagnosis and treatment of community-acquired pneumonia. Am Fam Physician. 2006;73:442-450.
- Mandell LA, Wunderink RG, Anzueto A, et al. Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults. Clin Infect Dis. 2007;44 Suppl 2:S27-S72.