Procalcitonin-Guided Therapy Reduces Amount of Antibiotics Used in CAP

May 31, 2005

May 31, 2005 (San Diego) — Measurement of the level of the hormone procalcitonin may reduce unnecessary antibiotic use in patients with pneumonia as well as reduce days of usage when antibiotics are required, Swedish researchers reported here at the 2005 American Thoracic Society International Conference.

A study of 300 patients with community-acquired pneumonia found that the number of days of antibiotic use could be cut in half from the usual 12 days to 6 days depending on the measurement of procalcitonin levels. Additionally, 15% of patients who usually would have received antibiotics were not prescribed any after procalcitonin levels deemed them unnecessary.

"The amount of antibiotic exposure was dramatically reduced with procalcitonin-guided therapy," said coauthor Michael Tamm, MD, chief of pulmonary medicine and pulmonary cell research, University Hospital, Basel, Switzerland.

Patients with community-based pneumonia were randomized to receive standard antibiotic treatment for 10 to 14 days or to receive antibiotics based on their procalcitonin levels. Standard therapy was given to 101 patients, and procalcitonin-guided therapy was provided for 99 patients. Baseline characteristics of patients were similar.

Patients receiving guided-procalcitonin therapy generally were prescribed antibiotics if their hormone levels were 0.25 g/L or higher, although physicians prescribed antibiotics if they found it necessary.

There was no difference in the clinical, radiographic, and laboratory outcomes between the standard antibiotic group and the guided-procalcitonin therapy group. In addition, mortality in both groups was about 14%.

Dr. Tamm said the procalcitonin levels only rise in response to bacterial infections, which are treated with antibiotics, and not in response to viral infections in which antibiotics usually are not prescribed.

If it is difficult to determine whether patients have viral or bacteria pneumonia, blood tests are extremely useful, Dr. Tamm said during a press conference. "The tests are good with both groups." Also, the blood tests are not expensive, said Dr. Tamm.

"However, the guided-procalcitonin therapy will not change practice tomorrow, but it is an interesting and intriguing, preliminary study," commented Andrew Ries, MD, professor of medicine, family, and preventive medicine, University of California at San Diego. "The cost of treating hospitalized patients with pneumonia and reduction of hospital stays are big issues."

This is a relatively small, single-blinded study, and it needs to be repeated in a larger and different population, Dr. Tamm said.

2005 ATS International Conference: Poster C86. Presented May 24, 2005.

Reviewed by Gary D. Vogin, MD

Linda Little is a freelance writer for Medscape.