A research team wanted to know if a common blood test for inflammation, called C-reactive protein (CRP), could help doctors identify a serious bone infection called osteomyelitis in people with diabetic foot wounds. They looked back at medical records from 265 patients and combined their findings with data from 12 previous studies involving over 1,800 patients total. This type of study is called a meta-analysis.
In the combined analysis of all the studies, the CRP test correctly identified about 74% of people who had the bone infection and correctly ruled it out in about 73% of people who did not have it. This is considered moderate accuracy. However, in the researchers' own smaller group of 265 patients, the test's accuracy was lower. A specific test result level was suggested, but using it would miss some infections and could also incorrectly flag many people who don't have one.
No safety issues with the blood test itself were reported, as it is a standard lab test. The main reason for caution is that this research only looked at past data. The test's performance was not consistent across all studies, and it was not tested prospectively to see how well it works in real-time clinical decisions. For now, this analysis suggests CRP could be one helpful piece of information among others, but it is not a definitive standalone test for this complex infection.