Effects of disease activity on anti-Saccharomyces cerevisiae antibodies: implications for diagnosis and follow-up of children with Crohn's disease.
BACKGROUND
To determine diagnostic accuracy of anti-Saccharomyces cerevisiae antibodies (ASCA) in identifying children with inflammatory bowel disease (IBD) and to differentiate Crohn's disease (CD) from other IBD forms; and to determine the effect of medical or surgical treatment and of disease location and activity on ASCA titers.


METHODS
Serum samples were obtained from 196 IBD children and 142 controls. ASCA IgA and IgG titers were measured by ELISA. Measurements were repeated during the follow up of CD children.


RESULTS
ASCA titers were significantly higher in CD than in other IBD and in control patients. Combination of IgA and IgG ASCA positivity was highly specific for CD. Medical treatment and disease location did not influence assay results. Significantly lower ASCA titers were obtained in CD children with intestinal resection compared to CD-affected children who did not undergo surgical resection. ASCA titers correlated significantly with disease activity, and children with severe active disease showed higher ASCA values compared to those in remission. A significant reduction of ASCA was observed during the follow-up of CD children when clinical remission was achieved.


CONCLUSIONS
The diagnostic accuracy of ASCA is influenced by disease activity and this suggests an additional use for the follow-up of CD children of this assay.
Canani
Roberto Berni
RB
Department of Pediatrics, University Federico II, Naples, Italy. berni@unina.it
Romano
Maria Teresa
MT
Greco
Luigi
L
Terrin
Gianluca
G
Sferlazzas
Concetta
C
Barabino
Arrigo
A
Fontana
Massimo
M
Roggero
Paola
P
Guariso
Graziella
G
De Angelis
GianLuigi
G
Fecarotta
Simona
S
Polito
Gaetano
G
Cucchiara
Salvatore
S
D000293:Adolescent; D000328:Adult; D000908:Antibodies, Fungal / Q000097:blood*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003424:Crohn Disease / Q000175:diagnosis / Q000276:immunology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007223:Infant; D015212:Inflammatory Bowel Diseases / Q000175:diagnosis* / Q000276:immunology*; D008297:Male; D012441:Saccharomyces cerevisiae / Q000276:immunology*; D012680:Sensitivity and Specificity
D000908:Antibodies, Fungal