By Lisa Rapaport

(Reuters Health) – - Some patients with bacterial respiratory infections may be able to skip antibiotics, a recent study suggests.

That's because most lower respiratory infections caused by bacteria are not much more severe than infections with other causes, researchers say.

“Physicians fear missing lower respiratory tract infection with a bacterial cause, because they generally assume that disease course is more severe and prolonged in these patients and prescribe antibiotics as a defensive strategy,” lead study author Dr. Jolien Teepe of University Medical Center Utrecht in The Netherlands told Reuters Health by email.

“Our results show that the illness course of bacterial lower respiratory tract infection is generally mild, uncomplicated, and similar to that of nonbacterial lower respiratory tract infection and does not warrant the immediate prescribing of antibiotics,” Teepe added.

Antibiotics only fight bacterial infections, not viruses like colds, flu and most sore throats.

For the current study, researchers examined data on 834 adults who visited primary care providers with an acute cough and were diagnosed with lower respiratory tract infections.

Most of the participants had viral infections that wouldn’t respond to antibiotics, while 162 had bacterial infections.

Patients with bacterial infections were more likely to be smokers and to have lived with the cough a little longer before seeing a doctor, compared to people with viral infections.

Doctors generally assessed symptoms as a bit more severe in patients with bacterial infections.

None of them – even patients with bacterial infections – received antibiotics.

All of them kept symptom diaries for four weeks.

In the first two to four days after the initial check-up for the cough, patients with bacterial infections reported worse symptoms than people with viral infections, researchers report in the Annals of Family Medicine.

With bacterial infections, 27 percent of patients felt bad enough to return to the doctor at least once during the study, compared to 17 percent with viral infections.

But by the end of four weeks, patients with different types of infections didn’t report clinically meaningful differences in how much their worst symptoms had improved.

One limitation of the study is that more severely ill patients were referred to a hospital and excluded from the analysis, leaving only people with milder symptoms, the authors note.

Researchers also were not able to follow the full course of the illness for 7 percent of patients who still reported moderately bad or severe symptoms at the end of the four-week study.

Even so, the findings add to a growing body of evidence suggesting that antibiotics may not benefit people with respiratory infections, particularly when pneumonia isn’t suspected, said Dr. Louise Vaz, an infectious disease researcher at Oregon Health and Science University’s Doernbecher Children’s Hospital in Portland.

“Antibiotics will be needed if there is concern for pneumonia,” Vaz, who wasn’t involved in the study, said by email. “However, for the majority of patients presenting to their doctor for cough, antibiotics may not be needed.”

Each time patients take antibiotics they don’t need, they also contribute to the development of superbugs that are resistant to treatment with these medicines, noted Dr. Sharon Meropol, a researcher at Case Western Reserve University School of Medicine in Cleveland, Ohio.

“The bigger picture is that the more antibiotics we use for society as a whole, the faster antibiotic resistance will develop, and future bacterial infections for all of our patients will become increasingly difficult to treat,” Meropol said by email.

“That’s why judicious antibiotic use, using them only when they are likely to be of benefit, will preserve antibiotics’ usefulness as long as possible for each of us individually, as well as for society as a whole,” Meropol added.

SOURCE: http://bit.ly/2fXSdTw Annals of Family Medicine, online November 14, 2016.