Last week I saw a 35-year-old man for follow-up on a positive rapid plasma reagin (RPR). He thought he had syphilis, but he had never had any syphilis symptoms, so I suspected the RPR was a false positive. Because I seldom encounter this situation, it was time for some “point of care” research. I checked an online reference and found that the fluorescent treponemal antibody absorption (FTA-ABS) test is highly sensitive and would be sufficient to rule out syphilis. The good news: His subsequent FTA-ABS was negative. But the situation left me wondering why the FTA-ABS had not been done automatically after the positive RPR.
The question, “What is the best test to rule in or rule out X?” comes up frequently for family physicians (FPs), and sometimes we are uncertain about ordering the best test and interpreting the results correctly. According to a recent national survey sponsored by the Centers for Disease Control and Prevention1—for which I was privileged to be the principal investigator—1768 FPs and general internists reported ordering diagnostic laboratory tests for an average of 31.4% of their patients per week. They were uncertain about the right test to order for 14.7% of these patients and uncertain about interpreting the results for 8.3%. That might not seem like a lot, but with more than 500 million primary care patient visits per year in the United States, this potentially affects 23 million patients each year.
We asked about problems with test ordering, too. I don’t think you will be surprised that physicians reported insurance company restrictions and costs to patients were the main barriers. They also reported difficulty with the variety of names for the same tests, which I certainly noticed when I moved from Cleveland Clinic to University of Illinois at Chicago. Not getting test results in a timely manner was a big problem, too, as was confusing report formats. In our electronic medical record, 90% of the lab report details things I don’t need to know and to get to the 10% I do need, I have to scroll or click.
In this issue, Tessier et al illustrate ways to avoid common lab testing pitfalls. I would argue that in addition to helpful articles like this one, we also need better electronic tools to help guide us when uncertain. Then again, the phone is still good technology; when in doubt, pick it up and call your lab.