How many lumbar punctures (LPs) should be performed during hospitalization for proper management of a case of meningitis? To date this question has not been answered to everyone's satisfaction. However, a new dilemma concerning LP and meningitis has arisen. This is related to the need for a second LP to make an initial diagnosis of meningitis.
Fischer and his associates, elsewhere in this issue (see page 590), as well as Rapkin,1 have reported a number of cases of meningitis in which the cerebrospinal fluid CSF obtained on the initial LP was essentially normal. A second LP, at times performed only a few hours later, disclosed purulent fluid. A common denominator in many of these cases was a positive blood culture that was obtained on admission to the hospital. These observations led to the conclusion that "a positive blood culture mandates a repeat LP,"1 particularly in small infants according
SHINEFIELD HR. Bacteremia, Lumbar Punctures, and Meningitis. Am J Dis Child. 1975;129(5):547-548. doi:10.1001/archpedi.1975.02120420003001