[Blood cell count in neonatal bacterial infections]

To determine the usefulness of the hemogram in the study of neonatal infections, we examined 92 neonates in the early stage of bacterial infection. Eighty-seven percent of these patients had one or more abnormalities in the differential leucocyte counts. A ratio of immature to total neutrophil greater than 0.20 was the most frequently found abnormality (60%). Hematologic complications were anemia (35%), and thrombocytopenia (12%). Neutropenia, and thrombocytopenia were associated with greater risk of death from infection. Lethality rate in all infants studied was 17.4% (16 of 92), which increased to 70% (7 of 10) in those patient with neutrophil counts less than 1,000/mm3. All newborns with neutrophilia survived. In this study, the hemogram was of value in the early diagnosis of bacterial infection, and in the detection of hematologic complications. In addition, several parameters associated to the severity of disease were identified.