Nucleated red blood cells and serum lactate values on days 2 and 5 are associated with mortality and morbidity in VLBW infants.

ABSTRACT

AIM: To correlate nucleated red blood cell counts and serum lactate concentrations on day 2 and 5 of life with morbidity and mortality in very low birth weight infants and to determine corresponding cutoff values. METHODS: Retrospective analysis in a cohort of very low birth weight infants. RESULTS: 250 very low birth weight infants were included in this study. Gestational age ranged from 23 to 35 weeks (mean 29.04) and birth weight was 320-1500 g (mean 1047.9). 55 (22%) patients developed intraventricular hemorrhage, 55 (22%) bronchopulmonary dysplasia, 12 (4.8%) periventricular leukomalacia, 93 (37.2%) retinopathy of prematurity, and 1 (0.4%) necrotizing enterocolitis. Mortality rate was 25/250 (10%). Nucleated red blood cells and serum lactate on day 2 of life were associated with mortality (p < 0.001). Serum lactate on day 5 of life demonstrated an association with retinopathy of prematurity (p = 0.017), bronchopulmonary dysplasia (p = 0.044), and intraventricular hemorrhage (p < 0.001). Cutoff values predicting mortality were >89.5 nucleated red blood cells/100 leucocytes (sensitivity 68.2%, specificity 89.0%) and serum lactate concentrations >8.5 mmol/l (sensitivity 69.6%, specificity 93.5%) on day 2 of life. CONCLUSION: We conclude that both nucleated red blood cell count and serum lactate concentration are valuable biomarkers in predicting important outcome parameters in very low birth weight infants.