Diagnostic and prognostic utility of C-reactive protein, alpha-1-antitrypsin and alpha-2-macroglobulin in neonatal sepsis: a comparative account.

C-reactive protein (CRP), alpha-1-antitrypsin (alpha-1-AT) and alpha-2-macroglobulin (alpha-2-MG) levels were evaluated serially in 25 healthy and 20 septicemic neonates and then compared as early diagnostic aids and prognostic indicators in this illness. Compared to healthy controls, septicemic neonates had significantly higher mean CRP levels (p less than 0.01). Neonates with septicemia, who recovered, had higher mean CRP levels than the group which died (p less than 0.05). As an early diagnostic aid CRP had a low Youden index, whereas for prognosis its index was higher. Septicemic neonates also had significantly higher mean alpha-1-AT levels (p less than 0.05), 12-24 hours after onset of illness, as compared to healthy neonates. Alpha-1-antitrypsin could not be used as an early diagnostic aid in septicemia, but was useful for predicting outcome. Mean alpha-2-macroglobulin levels did not show significant variation in healthy and septicemic neonates. Lower mean alpha-2-MG levels were observed in neonates recovering from septicemia. As an early diagnostic aid alpha-2-MG had a low Youden index, whereas for prognosis its index was higher. CRP had a higher Youden index than alpha-2-MG for early diagnosis of neonatal septicemia and had a higher index than both alpha-1-AT and alpha-2-MG for predicting outcome in septicemia. Serial use of CRP alone is, therefore, recommended for both purposes.