Cannot Rely on Complete Blood Cell Count to Rule Out Early Onset Neonatal Sepsis

Using an administrative database from 293 U.S. neonatal intensive care units, researchers retrospectively examined the utility of complete blood count (CBC) for diagnosis of early onset neonatal sepsis (EOS) in 166,092 neonates (mean gestational age, 34.6 weeks) with suspected EOS and culture results from blood (98%), urine (0.2%), or cerebral spinal fluid (CSF; 1.5%) from the first 3 days of life. EOS was defined as a positive culture from the first 3 days of life. CBC indices were compared with positive culture results by logistic regression.

Among the 2164 infants (1.3%) with positive cultures, 92% had bacteremia. Low white blood cell (WBC) count, low absolute neutrophil count (ANC), high immature-to-total neutrophil ratio (I/T ratio), an…