Validation of the Rule of 7's for Identifying Children at Low-risk for Lyme Meningitis.

TitleValidation of the Rule of 7's for Identifying Children at Low-risk for Lyme Meningitis.
Publication TypeJournal Article
Year of Publication2021
AuthorsGarro A, Avery RA, Cohn KA, Neville DN, Balamuth F, Levas MN, Bennett JE, Kharbanda AB, Monuteaux MC, Nigrovic LE
Corporate Authorsfor Pedi Lyme Net
JournalPediatr Infect Dis J
Date Published2021 Apr 01

BACKGROUND: The Rule of 7's classifies children as low-risk for Lyme meningitis with the absence of the following: ≥7 days of headache, any cranial neuritis or ≥70% cerebrospinal fluid mononuclear cells. We sought to broadly validate this clinical prediction rule in children with meningitis undergoing evaluation for Lyme disease.

METHODS: We performed a patient-level data meta-analysis of 2 prospective and 2 retrospective cohorts of children ≤21 years of age with cerebrospinal fluid pleocytosis who underwent evaluation for Lyme disease. We defined a case of Lyme meningitis with a positive 2-tier serology result (positive or equivocal first-tier enzyme immunoassay followed by a positive supplemental immunoblot). We applied the Rule of 7's and report the accuracy for the identification of Lyme meningitis.

RESULTS: Of 721 included children with meningitis, 178 had Lyme meningitis (24.7%) and 543 had aseptic meningitis (75.3%). The pooled data from the 4 studies showed the Rule of 7's has a sensitivity of 98% [95% confidence interval (CI): 89%-100%, I2 = 71%], specificity 40% (95% CI: 30%-50%, I2 = 75%), and a negative predictive value of 100% (95% CI: 95%-100%, I2 = 55%).

CONCLUSIONS: The Rule of 7's accurately identified children with meningitis at low-risk for Lyme meningitis for whom clinicians should consider outpatient management while awaiting Lyme disease test results.

Alternate JournalPediatr Infect Dis J
PubMed ID33710975