Serum C-reactive protein in early diagnosis of bacterial infections in premature infants

Serum C-reactive protein (CRP) is known to be produced by full-term infants and children in many diseases causing severe inflammation. We examined the usefulness of CRP as an early indicator of bacterial infection in premature newborn infants. CRP was obtained from 100 patients enrolled in a prospective study. All babies were suspected of having bacterial infection (meningitis-septicaemia) because of complications during pregnancy and/or symptoms suggestive of infection during the perinatal period. CRP was measured with the radial immunodiffusion technique. Examinations were done daily as long as elevated serum CRP levels were found. 100% (6/6) of our patients with culture-proven bacterial infections showed elevated CRP values within 24 h after the first clinical or laboratory signs suggesting sepsis. In 52.3% (11/21) of cases most probably suffering from infection, CRP rose within 72 h after the appearance of other symptoms. Even extremely immature infants were able to react with elevated CRP concentrations. Peak values of CRP were independent of birth weight. On the other hand, only 2.7% (2/73) of babies without findings of infection had slightly elevated amounts of CRP for a short time. Thus, serum CRP levels are a helpful parameter for the early diagnosis of severe bacterial infection in premature infants.