Normative Cerebrospinal Fluid Profiles in Febrile Infants

Objective To describe the cerebrospinal fluid (CSF) profiles of febrile infants aged 1 to 90 days with negative bacterial culture test results and negative results for enteroviruses with polymerase chain reaction. Study design Statistical analysis of a retrospective cohort. Results CSF profiles from 823 infants with negative test results for infection were analyzed. For 677 infants with atraumatic lumbar punctures (red blood cell [RBC] count <1000/mm(3)), the mean and median CSF white blood cell (WBC) counts were 4.3/mm(3) and 3.0/mm(3), respectively, with a range from 0 to 12/mm(3). Mean CSF WBC counts (6.1/mm(3) versus 3.1/mm(3) and 3.0/mm(3)) and protein levels (75.4 mg/dL versus 58.9 mg/dL and 39.2 mg/dL) were higher in the first month compared with months 2 and 3, respectively (P < .001 for all). CSF glucose levels were lower in the first month compared with month 3 (45.3 mg/dL versus 48.0 mg/dL and 57.7 mg/dL; P < .001). Increasing RBC counts were statistically associated with increasing WBC counts (P < .001). However, the contribution of RBC < 10 000/mm(3) was small, and the reference range for WBC in uninfected infants with traumatic lumbar punctures was 0 to 16/mm(3). Conclusion CSF WBC counts in febrile infants without evidencse of bacterial or enteroviral infection, even in those with traumatic lumbar puncture, are lower than reported in pediatric references. (J Pediatr 2011; 158: 33-7).