Lyme disease diagnosis based on clinician suspicion often inaccurate
Clinician suspicion had minimal accuracy in differentiating between children with and without Lyme disease who presented to the ED, according to findings published in Pediatrics.
“Clinicians use clinical prediction rules to combine available demographic, clinical and laboratory factors to estimate the probability of an outcome and assist clinical decision-making. However, the considerable overlap between Lyme disease and its mimics limits the clinical applicability of these predictive models,” Lise E. Nigrovic, MD, MPH, from the division of emergency medicine at Boston Children’s Hospital, and colleagues wrote. “The ability of clinician suspicion to accurately identify children at either high or low risk for Lyme disease has not been rigorously evaluated.”
To examine the accuracy of clinician suspicion for Lyme disease, researchers conducted a prospective cohort study of children aged 1 to 21 years who were examined for Lyme disease in EDs. They asked treating clinicians to estimate the probability of Lyme disease on a 10-point scale, with 1 being “not likely to be Lyme disease” and 10 being “very likely.”
They constructed receiver operating characteristic curves then used the area under the curve (AUC) to quantify the discriminative ability of clinicians, with AUC less than 0.7 considered poor discriminatory value, AUC between 0.7 and 0.8 as minimally accurate, AUCs of 0.8 to 0.9 as good accuracy and AUCS of more than 0.9 as excellent accuracy.
Of 1,021 children enrolled in the study, 238 (23%) had Lyme disease. Clinician suspicion had a minimal ability in determining whether children had Lyme disease or did not (AUC, 0.75; 95% CI, 0.71-0.79).
Of 554 children who the treating physicians thought were unlikely to have the disease (score 1-3), 12% had Lyme disease. Out of 127 patients who the treating physicians thought were very likely to have Lyme (score 8-10), 31% did not have the disease. These findings suggest that although clinician suspicion of Lyme disease can assist with initial management, final decisions and diagnoses should not be made until laboratory confirmation arrives.
“New approaches for the diagnosis of Lyme disease that include more rapid and more accurate diagnostic tests are needed,” Nigrovic and colleagues wrote. “Although 2-tiered Lyme disease serology takes several days to return results in more clinical settings, final patient management decisions should await confirmatory test results to avoid both over- and underdiagnosis of Lyme disease.” – by Savannah Demko
Disclosure: The authors report no relevant financial disclosures.