Biomarkers for neonatal sepsis: recent developments

Figures & data

Table 1 Characteristics of an ideal biomarker for neonatal sepsis

Discriminate etiology of sepsis	Able to identify causes of sepsis such as viral, bacterial, or fungal
High sensitivity	The ability to detect sepsis in infants where sepsis is present (approaching 100%)
High specificity	The ability to rule out sepsis in infants where sepsis is absent (>85%)
High predictive value	Likelihood that the test accurately predicts presence or absence of sepsis (approaching 100%)
Rapid timely results	Necessary in early sepsis diagnosis generally in <60 minutes
Reliable and precise	Informs in early diagnosis, guides treatment decisions or prognosis
Readily available standardized method	Technology can be available from commonly obtainable small volume sample and expanded routinely among care institutions

Table 2 Cytokine classification

Pro-inflammatory Th1-type, stimulatory	Anti-inflammatory Th2-type, inhibitory	Multifunctional
IFNγ	IL-4, IL-10, IL-1ra, IL-2	IL3, IL-1β
TNFα	TNFsr	MCP-1
IP-10	TGF-β2	sCD40L
IL-2, IL-6, IL-8, IL-12, IL-17		Growth factors: IL3 and G-CSF

Abbreviations: G-CSF, granulocyte colony stimulating factor; IFNγ, interferon-gamma; IL, interleukin; IP-10, inducible protein-10; MCP-1, monocyte chemoattractant protein-1; sCD40L, soluble CD40 ligand; TGF-β2, tumor growth factor β2; TNFα, tumor necrosis factor α; TNFsr, tumor necrosis factor soluble receptor.

Table 3 Characteristics of common biomarkers

Biomarker	Sensitivity/specificity (%)	Negative predictive value (%)	Useful in early disease diagnosis <24 hours	Useful in disease progression	Short half-life	Reference
C-reactive protein	30–68/98	74–83	No	Yes	No	40–44
Procalcitonin	92/97	96	Yes	No	Yes	45,47,55
Serum amyloid A	23–96/45–95	99	Yes	No	No	57,58
IL-6	54–90/96	67–91	Yes	No	Yes	8,9,33,109
IL-8	78–90/75–100	76	Yes	No	Yes	5,75,109
CD64	80	89	Yes	No	No	14,34,89,92
sCD163	100/88	100	Yes	No	No	108,109
Combined: IL-6/IL-10/RANTES	100/97	100	Yes	Yes	No	31
Combined: CD64/IL-6 or CRP	100/99	100	Yes	Yes	No	36,52

Abbreviations: CRP, C-reactive protein; sCD163, soluble CD163; IL, interleukin; RANTES, regulated on activation, normal T cell expressed and secreted.