Prevalence and significance of perinuclear anti-neutrophil antibodies (pANCA) in Romanian patients with Crohn's disease and ulcerative colitis.

Introduction: Antineutrophil cytoplasmic antibodies (ANCA) are known as a serologic marker of immune disturbances in IBD. The most specific are perinuclear ANCA (pANCA). The aim of this study was to investigate their significance for the diagnosis of inflammatory bowel disease (IBD) in Romania.

Material And Methods: A prospective longitudinal study, comprising all patients admitted to our Center in 2000 with ulcerative colitis--UC group (33 patients) and with Crohn's disease--CD group (40 patients). The control group (C) included 22 healthy individuals, with similar age and sex distribution. ANCA was tested in serum by indirect immunofluorescence at Leuven University, Belgium.

Results: ANCA prevalence in UC group was 12/33 (36.4%), in CD group was 6/40 (15%), while in the C group all sera tested negative (p=0.004). All ANCA antibodies in patients with IBD were perinuclear type. In the UC group, the prevalence of pANCA was higher in females compared to males (52.9% versus 16.7%, p=0.04). The phenotype pANCA+ did not correlate with disease extension, severity, the evolutive form or complications. In the CD group, the phenotype pANCA+, although more frequently found in colonic involvement and in non-obstructive non-fistulizing forms to associate with pANCA+, did not reach statistical significance (p=0.59). A higher severity of CD was associated with higher pANCA titers (p=0.05).

Conclusion: pANCA prevalence in UC in Romania was lower in comparison with other studies (36.4% versus 50-80%). The highest prevalence was found in females with UC. In CD, pANCA+ was associated with a higher severity. pANCA assessment remains at a research level, further in-vestigations being necessary in order to demonstrate its clinical importance.