Table 3.

Utility of Total WBC, ANC, and IL-6 in Predicting Occult Bacteremia in Febrile Young Children

Tests*SensitivitySpecificityPositive Predictive ValueNegative Predictive ValueOR (95% CI)
WBC >1548%79%5.5%98.3%3.5 (1.1–10.7)
ANC >720082%74%7.5%99.4%12.8 (3.2–59.7)
IL-6 >9588%70%7.0%99.6%16.7 (4.8–71.6)
IL-6 >65 and ANC >5000100%78%10.4%100%Undefined(33.0–∞)
  • Abbreviations: WBC, white blood cell count; ANC, absolute neutrophil count; IL-6, interleukin-6.

  • * WBC (×109 cells/L), ANC (cells/mm3), and IL-6 (pg/mL).

  • Positive and negative predictive values calculated using a prior probability of 2.5%.

  • ORs are undefined for any test with a sensitivity of 100%.