Corticosteroids are often used to treat inflammation related to infectious diseases, such as bacterial meningitis, but they have been rendered ineffective in case of other infectious diseases.
In a new study, scientists have shown that mice with a type of severe bacterial pneumonia, when treated with steroids and antibiotics recovered faster.
The steroid treated mice had far less inflammation in their lungs than mice treated with antibiotics alone.
"Some people might think that if you give steroids, it would counteract the effect of the antibiotic. But it turns out you need the antibiotic to kill the bug and the steroid to make the inflammation in the lung from the infection get better. The steroids don't kill the bugs, but they do help restore health," said Dr. Robert Hardy, associate professor of internal medicine and pediatrics and the study's senior author.
For the study, the researchers gave a daily treatment of a placebo, an antibiotic, a steroid, or a combination of the antibiotic and steroid to mice infected with the M pneumoniae bacterium. The animals were then evaluated after one, three and six days of therapy.
"It turns out that the group that got both the antibiotic and the steroids did the best. The inflammation in their lungs got significantly better," said Hardy .
While antimicrobials have been the primary therapy for M pneumoniae infection, many physicians have tried adding steroids to the treatment regimen of patients with severe cases. But, Hardy said that the problem is that those were individual case reports.
"They never had a control group, so it was impossible to tell what impact the addition of steroids had on recovery," he said.
The new findings suggest that giving antibiotics with steroids can help individuals with pneumonia get better faster.
Also, the research suggests a potentially more effective therapy for someone in the midst of an asthma attack due to M pneumoniae infection.
The study is available online and in a future issue of the Journal of Infectious Diseases.