Evaluation of proadrenomedullin as a diagnostic or prognostic biomarker of acute appendicitis in children.
BACKGROUND
A delay in the diagnosis of acute appendicitis (AA), with the added complication of symptoms that mimic other self-limited causes of abdominal pain, can lead to an increase in ruptured appendices and morbimortality. None of the serum biomarkers evaluated to date have shown a predictive value for early diagnosis.


OBJECTIVE
The objective of this study was to evaluate the usefulness of proadrenomedullin (MR-proADM) in the diagnosis of AA in children presenting with acute abdominal pain.


METHODS
A single-center prospective observational study was conducted in 136 children who presented to the emergency department with suspected AA.


RESULTS
Forty-four (32.5%) children had AA, and 9 (20.5%) had perforated appendicitis. The mean concentration of MR-proADM was significantly higher in children with AA than in children with nonspecific abdominal pain (NAP) (0.54 nmol/L; 95% confidence interval, 0.46-0.55 and 0.37 nmol/L; 95% confidence interval, 0.35-0.40, respectively). Performance characteristics of MR-proADM alone were not optimal. However, after combining best cutoff points, the combination of a C-reactive protein level of <0.3 mg/dL and a MR-proADM level of <0.34 nmol/L showed 100% sensitivity and negative predictive value, with 61% specificity.


CONCLUSIONS
Although MR-proADM values are higher in children with AA than in children with nonspecific abdominal pain, these values do not help in the early diagnosis of AA. The combination of low C-reactive protein and low MR-proADM levels is useful for the identification of children with a low risk of AA.
Pediatric Emergency Department, Hospital General Universitario Gregorio Marañón, Madrid 28007, Spain. Electronic address: c.miguez09@gmail.com.
Concepción
C
Míguez
Pediatric Emergency Department, Hospital General Universitario Gregorio Marañón, Madrid 28007, Spain. Electronic address: cristina.tomatis@nationwidechildrens.org.
Cristina
C
Tomatis Souverbielle
Pediatric Emergency Department, Hospital General Universitario Gregorio Marañón, Madrid 28007, Spain. Electronic address: anaharodiaz@hotmail.com.
Ana
A
Haro
Pediatric Emergency Department, Hospital General Universitario Gregorio Marañón, Madrid 28007, Spain. Electronic address: g.guerrero13@gmail.com.
Gloria
G
Guerrero
Pediatric Surgery Department, Hospital General Universitario Gregorio Marañón, Madrid 28007, Spain. Electronic address: lpegido@hotmail.com.
Laura
L
Pérez-Egido
Biochemistry Laboratory, Hospital General Universitario Gregorio Marañón, Madrid 28007, Spain. Electronic address: mggamiz@salud.madrid.org.
Mercedes
M
García-Gamiz
Pediatric Emergency Department, Hospital General Universitario Gregorio Marañón, Madrid 28007, Spain. Electronic address: rafamaranonpar@gmail.com.
Rafael
R
Marañon
D015746:Abdominal Pain / Q000209:etiology; D000208:Acute Disease; D053607:Adrenomedullin / Q000097:blood*; D001064:Appendicitis / Q000097:blood* / Q000150:complications / Q000175:diagnosis*; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D010446:Peptide Fragments / Q000097:blood*; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D011498:Protein Precursors / Q000097:blood*; D012372:ROC Curve
D015415:Biomarkers; D010446:Peptide Fragments; D011498:Protein Precursors; C574167:mid-regional pro-adrenomedullin, human; D053607:Adrenomedullin; D002097:C-Reactive Protein