Diagnostic value of serological assays in pediatric inflammatory bowel disorders.
BACKGROUND
Pediatric studies reported that the combined use of the anti-neutrophil cytoplasm autoantibodies (ANCA) and the anti-Saccharomyces cerevisiae mannan antibodies (ASCA) may be a specific useful noninvasive test in the diagnosis of inflammatory bowel diseases (IBD).


OBJECTIVE
To evaluate the diagnostic accuracy of ANCA and ASCA in children with suspected IBD, and to see whether different commercially available assays (indirect immunofluorescence vs. ELISA) agree well enough in terms of analytical performance.


METHODS
Sixty-nine children (30 males, 39 females, age range 2-18 years) with suspicion of IBD entered the study. Before colonoscopy, a blood sample was also drawn to assess ASCA and ANCA.


RESULTS
A diagnosis of IBD was established in 47 patients; the remainder had infective or other causes of colitis. For ulcerative colitis, the association ASCA-/ANCA+ had 70% sensitivity and 86% specificity, with a positive predictive value of 82%. The association ASCA+/ANCA- had 86% sensitivity and 93% specificity for Crohn's disease, with a positive predictive value of 75%.


CONCLUSIONS
Although more experience is needed to state the diagnostic power of serologic assay, determination of ANCA and ASCA in IBD children may help both in distinguish these conditions from other entities and ulcerative colitis from Crohn's disease, particularly in doubtful cases.
Mainardi
Elsa
E
Department of Clinical Pathology, Ospedale Maggiore, Crema, Italy.
Villanacci
Vincenzo
V
Bassotti
Gabrio
G
Liserre
Barbara
B
Rossi
Elisa
E
Incardona
Paolo
P
Falchetti
Diego
D
Tonegatti
Luca
L
Montanelli
Alessandro
A
Barabino
Arrigo
A
Coccia
Cristina
C
Gambini
Claudio
C
D000293:Adolescent; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood; D000908:Antibodies, Fungal / Q000097:blood; D015415:Biomarkers / Q000097:blood; D002648:Child; D002675:Child, Preschool; D003113:Colonoscopy; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D007223:Infant; D015212:Inflammatory Bowel Diseases / Q000097:blood* / Q000175:diagnosis*; D008297:Male; D011237:Predictive Value of Tests; D012441:Saccharomyces cerevisiae / Q000276:immunology; D012680:Sensitivity and Specificity
D019268:Antibodies, Antineutrophil Cytoplasmic; D000908:Antibodies, Fungal; D015415:Biomarkers