Vincenzo Maniaci, Andrew Dauber, Scott Weiss, Eric Nylen, Kenneth L Becker, and Richard Bachur.
Division of Emergency Medicine, Children's Hospital Boston, Harvard Medical School, Boston, Massachusetts, USA.
Pediatrics. 2008 Oct 1;122(4):701-10.
ObjectivesThe objectives of the study were (1) to study the test performance of procalcitonin for identifying serious bacterial infections in febrile infants MethodsA prospective observational study was performed with febrile infants ResultsA total of 234 infants (median age: 51 days) were studied. Thirty infants (12.8%) had definite serious bacterial infections (bacteremia: n = 4; bacteremia with urinary tract infections: n = 2; urinary tract infections: n = 24), and 12 infants (5.1%) had possible serious bacterial infections (pneumonia: n = 5; urinary tract infections: n = 7). Mean procalcitonin levels for definite serious bacterial infections (2.21 +/- 3.9 ng/mL) and definite plus possible serious bacterial infections (2.48 +/- 4.6 ng/mL) were significantly higher than that for no serious bacterial infection (0.38 +/- 1.0 ng/mL). The area under the receiver operating characteristic curve was 0.82 for definite serious bacterial infections and 0.76 for definite and possible serious bacterial infections. For identifying definite and possible serious bacterial infections, a cutoff value of 0.12 ng/mL had sensitivity of 95.2%, specificity of 25.5%, negative predictive value of 96.1%, and negative likelihood ratio of 0.19; all cases of bacteremia were identified accurately with this cutoff value.ConclusionsProcalcitonin has favorable test characteristics for detecting serious bacterial infections in young febrile infants. Procalcitonin measurements performed especially well in detecting the most serious occult infections.