Can We Yet Escape The Neonatal Lumbar Puncture?

... maybe?

Nearly 95% of well-appearing febrile neonates have benign viral infections. Of those children who have invasive bacterial infection, the majority are UTIs or bacteremia. Can the PECARN “low risk” rule safely exclude the most invasive downstream testing – the lumbar puncture – in febrile young infants?

Across their cohort of 2,531 children, there were 96 true positives, 22 of which were meningitis. Of these, the PECARN rule (negative urine, procalcitonin < 0.5 ng/mL, and ANC < 4000) missed 5:

Obviously, with such a low absolute frequency of events, it’s not possible to even grossly estimate the actual miss rate of this rule for meningitis. However, this rule places the “number needed to LP” in the thousands or tens of thousands to pick up one case of bacterial meningitis. I suspect it is feasible to develop strategies where serial downstream evaluations drive further testing, and the initial LP is deferred.

Of course, these data may not generalize to our new, vaccine-free future …