Broad-Spectrum Antibiotics Ineffective as Initial Pneumonia Treatment

A new study shows that hospitalized pneumonia patients prescribed antibiotics that target methicillin-resistant Staphylococcus aureus (MRSA) fare no better than standard medical care.

Researchers at the Veterans Affairs Salt Lake City Health Care System (UT, USA) and the University of Utah (UU; Salt Lake City, USA) conducted a retrospective cohort study involving 88,605 hospitalized patients (median age 70 years, predominantly men) who received either anti-MRSA or standard therapy for community-onset pneumonia. The main outcomes were 30-day all-cause mortality, after adjustment for patient comorbidities, vital signs, and laboratory results. Secondary outcomes included kidney injury and secondary infections with Clostridioides difficile, vancomycin-resistant Enterococcus species, or gram-negative bacilli.

The results revealed no discernable benefit of anti-MRSA treatment in addition to standard treatment. In fact, anti-MRSA treatment was associated with a 40 % higher risk of dying within 30 days of discharge, perhaps due to potentially severe side effects of vancomycin, including increased incidence of kidney failure and secondary infections. The researchers also observed that as doctors became more aware of MRSA infection in the lungs, they tended to use anti-MRSA drugs as initial treatment, despite the fact that MRSA only accounts for about 2% of pneumonia cases. The study was published on February 17, 2020, in JAMA Internal Medicine.

“In the absence of better tests to identify MRSA as a potential pathogen causing the disease, using anti-MRSA therapies does not seem to offer any advantage over standard treatment therapy,” said lead author Barbara Ellen Jones, MD, MSc, of UU. “Under these circumstances, it may be safer for patients if physicians to stick to standard antibiotic treatments for a couple of days to see how patients are doing, rather than leaping into anti-MRSA therapy right off the bat.”

Pneumonia is the eighth leading cause of death in the United States, accounting for more than one million hospitalizations and about 50,000 deaths each year. It can be caused by viruses, fungi, and bacteria, including MRSA.

Related Links:
Veterans Affairs Salt Lake City Health Care System
University of Utah