title: Acute drop in blood monocyte count differentiates NEC from other causes of feeding intolerance.
abstract: OBJECTIVE
  Necrotizing enterocolitis (NEC) is characterized by macrophage infiltration into affected tissues. Because intestinal macrophages are derived from recruitment and in situ differentiation of blood monocytes in the gut mucosa, we hypothesized that increased recruitment of monocytes to the intestine during NEC reduces the blood monocyte concentration and that this fall in blood monocytes can be a useful biomarker for NEC.
  
  
  METHODS
  We reviewed medical records of very-low-birth-weight (VLBW) infants treated for NEC and compared them with a matched control group comprised of infants with feeding intolerance but no signs of NEC. Clinical characteristics and absolute monocyte counts (AMCs) were recorded. Diagnostic accuracy of AMC values was tested using receiver-operator characteristics (ROC).
  
  
  RESULTS
  We compared 69 cases and 257 controls (median 27 weeks, range 26 to 29 in both the groups). In stage II NEC, AMCs decreased from median 1.7 × 10(9) l(-1) (interquartile range (IQR) 0.98 to 2.4) to 0.8 (IQR 0.62 to 2.1); P < 0.05. In stage III NEC, monocyte counts decreased from median 2.1 × 10(9) l(-1) (IQR 0.1.5 to 3.2) to 0.8 (IQR 0.6 to 1.9); P < 0.05. There was no change in AMCs in control infants. ROC of AMC values showed a diagnostic accuracy (area under the curve) of 0.76. In a given infant with feeding intolerance, a drop in AMCs of > 20% indicated NEC with sensitivity of 0.70 (95% confidence interval (CI) 0.57 to 0.81) and specificity of 0.71 (95% CI 0.64 to 0.77).
  
  
  CONCLUSIONS
  We have identified a fall in blood monocyte concentration as a novel biomarker for NEC in VLBW infants.
authors.affiliation: 1] Division of Neonatology, Department of Pediatrics, University of Illinois at Chicago, Chicago, IL, USA  [2] Center for Neonatal and Pediatric Gastrointestinal Disease, Department of Pediatrics, University of Illinois at Chicago, Chicago, IL, USA.
authors.forename: J
authors.initials: J
authors.lastname: Remon
authors.affiliation: Department of Pediatrics, Division of Neonatology, Loyola University Stritch School of Medicine, Maywood, IL, USA.
authors.forename: R
authors.initials: R
authors.lastname: Kampanatkosol
authors.affiliation: Center for Neonatal and Pediatric Gastrointestinal Disease, Department of Pediatrics, University of Illinois at Chicago, Chicago, IL, USA.
authors.forename: R R
authors.initials: RR
authors.lastname: Kaul
authors.affiliation: Department of Pediatrics, Division of Neonatology, Loyola University Stritch School of Medicine, Maywood, IL, USA.
authors.forename: J K
authors.initials: JK
authors.lastname: Muraskas
authors.affiliation: 1] Intermountain Healthcare Women and Newborns Clinical Program, Ogden, UT, USA [2] McKay-Dee Hospital Center, Ogden, UT, USA.
authors.forename: R D
authors.initials: RD
authors.lastname: Christensen
authors.affiliation: 1] Division of Neonatology, Department of Pediatrics, University of Illinois at Chicago, Chicago, IL, USA  [2] Center for Neonatal and Pediatric Gastrointestinal Disease, Department of Pediatrics, University of Illinois at Chicago, Chicago, IL, USA [3] Department of Pharmacology, University of Illinois at Chicago, Chicago, IL, USA.
authors.forename: A
authors.initials: A
authors.lastname: Maheshwari
mesh_terms: D015415:Biomarkers; D016022:Case-Control Studies; D003937:Diagnosis, Differential; D020345:Enterocolitis, Necrotizing / Q000097:blood / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D019102:Infant, Very Low Birth Weight; D007958:Leukocyte Count; D008297:Male; D009000:Monocytes / Q000473:pathology*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers