IDSA: Rush to Treat Pneumonia May Lead to Unneeded Antibiotic Use

SAN DIEGO, Oct. 11 -- Rushing the decision to treat suspected pneumonia with antibiotics may lead to unnecessary treatment in a majority of cases, according to a small study reported here.

Fewer than half of the patients receiving antibiotics for suspected community-acquired pneumonia (CAP) had discharge diagnoses of pneumonia, Marnie Rosenthal, D.O., M.P.H., of Tufts-New England Medical Center in Boston reported at the Infectious Diseases Society of America.

An absence of signs and symptoms of pneumonia was common; "55% of patients treated for community-acquired pneumonia did not have chest x-ray findings to support the diagnosis," said Dr. Rosenthal. "Almost half had no fever and no leukocytosis."

Unnecessary antibiotic therapy confers a risk of adverse effects, contributes to antibiotic resistance, increases the cost of care, and increases hospital resource utilization, she added.

In 2003 the Infectious Diseases Society of America promulgated guidelines for management of CAP in partnership with the Center for Medicare and Medicaid Services and the Joint Commission on Accreditation of Healthcare Organizations (Clin Infect Dis 2003; 37:1405-1433). The guidelines included a recommendation to initiate antibiotic therapy within four hours of presentation.

Before publication of the guidelines, several studies had demonstrated survival advantages for CAP patients who started antibiotic therapy within four to eight hours of hospital admission (JAMA 1997; 287:2080-2084, JAMA 1990; 264:1969-1973, Qual Rev Bull 1993; 19:124-130). After publication of the guidelines, a study of Medicare patients with CAP demonstrated reduced hospital and 30-day mortality and length of stay in patients who started antibiotic therapy within four hours (Arch Intern Med 2004; 164:637-644).

However, in the face of diagnostic uncertainty, the potential for unnecessary antibiotic therapy is substantial. For example, one recent study found that more than 20% of patients seen in an emergency department for evaluation of possible CAP had atypical symptoms that could complicate diagnosis (Chest 2006; 130:16-21).

The guidelines have since been revised to remove references to the four-hour window for initiation of treatment, said Dr. Rosenthal. However, some clinicians might continue to follow the recommendation.

To examine the issue, investigators retrospectively reviewed records on 49 patients who came to the emergency department during January and February 2006 for evaluation of suspected CAP. All the patients began antibiotic therapy within four hours and were admitted to the hospital.

Review of baseline characteristics showed that 22 (45%) of the patients had a temperature greater than 100.4 degrees F, 13 (27%) had a leukocyte count greater than 10.9, 26 (53%) had fever or leukocytosis, and 27 (55%) had chest x-rays that were normal or revealed atelectasis.

The records also showed that infectious disease specialists were consulted in five cases, pulmonologists in 18, and cardiologists in seven.

At discharge 25 (51%) patients had diagnoses other than CAP. The diagnoses included other pulmonary disorders, such as bronchitis and asthma/COPD, as well as non-pulmonary conditions, such as coronary disease and gastrointestinal disorders.

Dr. Rosenthal acknowledged several limitations of the study, including its retrospective nature, the small number of charts reviewed, and the inability of a descriptive study to demonstrate anything other than associations.