"Atypical p-ANCA" in IBD and hepatobiliary disorders react with a 50-kilodalton nuclear envelope protein of neutrophils and myeloid cell lines

BACKGROUND & AIMS: Atypical "antineutrophil cytoplasmic antibodies" (ANCA) are present in patients with ulcerative colitis (UC), primary sclerosing cholangitis (PSC), and autoimmune hepatitis (AIH). Recently, we showed that atypical p-ANCA react with nuclear envelope proteins of neutrophils. Based on this observation, we aimed to characterize the nuclear antigen recognized by atypical p-ANCA. METHODS: We prepared cytoplasmic and nuclear extracts of human neutrophils, human HL-60, and murine 32D myeloid cells. Proteins were resolved by 1- and 2-dimensional gel electrophoresis. Reactive proteins were detected by immunoblotting with sera from 118 individuals (UC, 25; PSC, 28; AIH, 35; disease and normal controls, 30). Atypical p-ANCA (n = 64) were affinity-purified against the reactive protein and investigated for their immunofluorescence pattern using confocal microscopy. RESULTS: Immunoblotting showed reactivity to a myeloid-specific 50-kilodalton nuclear protein with an isoelectric point of pH 6.0 detected in 92% (59 of 64) of the patients with inflammatory bowel or hepatobiliary diseases and atypical p-ANCA. Affinity-purified antibodies against the 50-kilodalton protein gave a nuclear rim-like fluorescence on myeloid cells examined by immunofluorescence microscopy. Affinity-purified antibodies did not recognize antigens in nonmyeloid cells. CONCLUSIONS: Atypical p-ANCA in UC, PSC, or AIH recognize a 50-kilodalton myeloid-specific nuclear envelope protein.     

Antineutrophil cytoplasmic antibodies in Japanese patients with inflammatory bowel disease: prevalence and recognition of putative antigens

OBJECTIVE: Our aim was to investigate the prevalence of antineutrophil cytoplasmic antibodies (ANCA) in Japanese patients with ulcerative colitis (UC) and Crohn's disease (CD), and the putative antigens recognized by perinuclear staining pattern ANCA (p-ANCA)-positive sera. METHODS: Sera from UC (n = 52) and CD (n = 43) patients, and from healthy controls (n = 74) were studied. The indirect immunofluorescence (IIF) method was used for the detection of ANCA and its binding pattern. p-ANCA-positive sera were studied further for putative antigens. ELISAs using lactoferrin (Lf), myeloperoxidase (MPO), and cathepsin G (Cat G) as antigens were performed. RESULTS: ANCA was positive in 40 of the 52 (76.9%) UC (p-ANCA in 33) and in 32 of the 43 (74.4%) CD (p-ANCA in 31) patients. UC and CD patients showed significantly higher titers of p-ANCA than controls; however, no significant difference was observed between UC and CD. In UC, 23, 17, and nine of the 33 patients with p-ANCA-positive sera showed reactivity with Lf, MPO, and Cat-G, respectively. In CD, 21, 20, and 11 of the 31 patients with p-ANCA-positive sera showed reactivity with Lf, MPO, and Cat-G, respectively. Fourteen of the UC and six of the CD patients showed reactivity with two different antigens, and seven of the UC and 11 of the CD patients showed reactivity with all three antigens. The presence of anti-Lf and anti-MPO antibodies was further confirmed by Western blotting. CONCLUSIONS: ANCA is useful in distinguishing patients with IBD from normal subjects but is not sufficient for the differential diagnosis of CD and UC. p-ANCA reactivity might be derived from the recognition of heterogeneous neutrophil-associated antigens.     

Atypical, cytoplasmic and perinuclear anti-neutrophil cytoplasmic antibodies in patients with inflammatory bowel disease

Atypical, cytoplasmic and perinuclear anti-neutrophil cytoplasmic antibodies (x-, c- and pANCA, respectively) are associated with a variety of inflammatory diseases, including inflammatory bowel disease (IBD). Anti-neutrophil cytoplasmic antibodies are more common in patients with ulcerative colitis (UC) than in patients with Crohn's disease (CD). Most publications only refer to p- and cANCA in relation to IBD. We have prospectively evaluated the reactivity of sera from 58 patients with IBD and 10 healthy controls against human neutrophils with emphasis on the distinction of the ANCA types. The sera were incubated with ethanol- and formaldehyde-fixed granulocytes to differentiate between c-, p- and xANCA. The results showed that 10 of 24 patients with UC were positive for ANCA, whereas only one of 34 patients with CD was ANCA positive. These results correspond to a sensitivity of 42%, a specificity of 97%, a negative predictive value of 91% and a positive predictive value of 75% in UC. Of the 11 ANCA-positive sera, two showed a cytoplasmic staining pattern, three showed a perinuclear and six an atypical staining pattern. The disease activity was not correlated to either the ANCA titre or to the presence of ANCA in the serum. In conclusion, ANCA are of limited value in differentiating between UC and CD. Because the majority of ANCA in patients with IBD are xANCA, these ANCA should be explored by not only incubating on ethanol-fixed granulocytes, but also on formaldehyde-fixed granulocytes.     

Anti-neutrophil cytoplasmic antibodies (ANCA) and inflammatory bowel diseases in Chinese

Inflammatory bowel diseases are uncommon in the Chinese, but the incidence is rising. Their differentiation from infective colitis is often not clear-cut and diagnosing inflammatory bowel diseases can be difficult in Asia. We have studied Chinese patients with ulcerative colitis (N=19) and Crohn's disease (N=12) for anti-neutrophil cytoplasmic antibodies (ANCA) by indirect immunofluorescence (IIF) and enzyme-linked immunosorbent assays (ELISA). Patients with enteric fever (N=29) and irritable bowel syndrome (N=24) were recruited as controls. Seventy-three percent of ulcerative colitis patients exhibited either p-ANCA (31%) or c-ANCA (42%) by IIF. Twenty-five percent of Crohn's disease patients were found to be p-ANCA positive. However, these ANCA were nonreactive to anti- granule, antiproteinase 3, antimyeloperoxidase, or antilactoferrin. All positive patients had extensive colitis. Sera collected from patients suffering from enteric fever and irritable bowel syndrome were negative for ANCA by IIF and ELISA. We concluded that the detection of ANCA is helpful in diagnosing inflammatory bowel diseases. Further attempts to characterize these autoantibodies are needed.This study was partly supported by the Croucher Foundation (grant 1634-29) and Research Grant Committee (grant CUHK/34/92M).     

Significance of antineutrophil cytoplasmic antibody in adult patients with Henoch-Sch(o)nlein purpura presenting mainly with gastrointestinal symptoms

AIM: To test the clinical significance of antineutrophil cytoplasmic antibody (ANCA) in evaluation of adult Henoch-Schonlein purpura (HSP) patients presenting mainly with abdominal symptoms.METHODS: Twenty-eight consecutive HSP patients who presented predominantly with abdominal symptoms were enrolled in this study. Control subjects included 27 age-and sex-matched patients with peptic ulcer disease, colon cancer, acute gastroenteritis, irritable bowel syndrome and colonic polyps. ANCA was measured by indirect immunofluorescence (IIF) in all patients, and follow-up ELJSA was performed in patients with positive IIF tests.RESULTS: ANCA was detected in 9 HSP patients by IIF (2 were positive for c-ANCA and 7 were positive for p-ANCA). No ANCA was found in the control group. The sensitivity and specificity of a positive ANCA test (either c- or p-ANCA) were 32.1% and 100% respectively. Only one out of the 9 patients with positive ANCA by IIF had positive ANCA by ELISA and the antigen was myeloperoxidase (MPO). The patients positive for ANCA had higher HSP clinical scores, and were more likely to have renal function impairment. Patients with late purpura development were also associated with more severe clinical manifestations.CONCLUSION: A positive ANCA test is associated with more severe symptoms in HSP. After inflammatory bowel disease is excluded, a positive ANCA test provides a clue to the diagnosis of HSP presenting predominantly with abdominal symptoms.     

Significance of antineutrophil cytoplasmic antibody in adult patients with Henoch-Schönlein purpura presenting mainly with gastrointestinal symptoms

AIM： To test the clinical significance of antineutrophil cytoplasmic antibody （ANCA） in evaluation of adult Henoch-Schonlein purpura （HSP） patients presenting mainly with abdominal symptoms. METHODS： Twenty-eight consecutive HSP patients who presented predominantly with abdominal symptoms were enrolled in this study. Control subjects included 27 ageand sex-matched patients with peptic ulcer disease, colon cancer, acute gastroenteritis, irritable bowel syndrome and colonic polyps. ANCA was measured by indirect immunofluorescence （IIF） in all patients, and follow-up ELISA was performed in patients with positive IIF tests. RESULTS： ANCA was detected in 9 HSP patients by IIF （2 were positive for c-ANCA and 7 were positive for p-ANCA）. No ANCA was found in the control group. The sensitivity and specificity of a positive ANCA test （either c- or p-ANCA） were 32.1% and 100% respectively. Only one out of the 9 patients with positive ANCA by IIF had positive ANCA by ELISA and the antigen was myeloperoxidase （MPO）. The patients positive for ANCA had higher HSP clinical scores, and were more likely to have renal function impairment. Patients with late purpura development were also associated with more severe clinical manifestations. CONCLUSION： A positive ANCA test is associated with more severe symptoms in HSP. After inflammatory bowel disease is excluded, a positive ANCA test provides a clue to the diagnosis of HSP presenting predominantly with abdominal symptoms.     

Contribution of immunofluorescence to the identification and characterization of anti-neutrophil cytoplasmic autoantibodies. The role of different fixatives

OBJECTIVE: To study the sera from selected groups of antineutrophil cytoplasmic antibody (ANCA) positive patients by means of the indirect immunofluorescence test (ANCA-IIF) with different fixatives, in order to better discriminate among the various ANCAs (Ag-specificity and disease associations), especially those for which the antigen targets have not yet been identified. METHODS: Eighty pathological serum samples and 15 normal sera were evaluated. Pathological samples included sera from 30 ulcerative colitis (UC) ANCA positive patients, 30 P-ANCA/myeloperoxidase (MPO-ANCA) positive microscopic polyangiitis (MPA) patients, 10 C-ANCA/proteinase 3 (PR3-ANCA) positive Wegener's granulomatosis (WG) patients, and 10 antinuclear antibody (ANA) positive (ANCA negative) systemic lupus erythematosus (SLE) patients. ANCA were detected by IIF on ethanol, methanol and formalin-fixed granulocytes and by ELISAs specific for MPO, PR3, lactoferrin (LF) and bactericidal/permeability-increasing protein (BPI). Additionally, sera were tested for the presence of antinuclear antibodies on IIF. RESULTS: 96% of serum samples from UC patients, positive by IIF on ethanol-fixed granulocytes, became negative when tested on formalin-fixed neutrophil slides. On the contrary, 95% of sera from vasculitic patients showed a clear diffuse granular cytoplasmic pattern on the same substrate; sera from all 10 SLE patients did not show any reactivity when formalin was used as fixative. On methanol-fixed neutrophils, 100% of UC P-ANCA positive sera were positive with the same pattern versus only 20% of vasculitic P-ANCA positive (MPO positive). Methanol fixation had no effect on PR3-ANCA and ANA positive sera. CONCLUSION: The comparison of IIF patterns of sera tested on different fixed cells may be useful to distinguish vasculitis-related P-ANCA versus ANA and vasculitis-related P-ANCA versus UC-related P-ANCA.     

Alpha1-antitrypsin phenotypes and anti-neutrophil cytoplasmic auto-antibodies in inflammatory bowel disease

OBJECTIVES: Alpha1-antitrypsin (alpha1-AT) is encoded by a highly polymorphic gene with over 75 codominantly expressed alleles at the protease inhibitor (Pi) locus classified as normal, deficient, dysfunctional or null. The aim of this study was to determine in patients with inflammatory bowel disease: (i) the prevalence of anti-neutrophil cytoplasmic auto-antibodies (ANCA) and their antigen specificities; (ii) alpha1-AT Pi phenotypes; and (iii) possible associations between ANCA, disease activity and deficient alpha1-AT alleles. DESIGN: Study of 95 consecutive patients with ulcerative colitis (UC) and 63 patients with Crohn's disease (CD). METHODS: Diagnosis and disease activity were determined by clinical, endoscopic and histological criteria. ANCA by indirect immunofluorescence (IIF) and Pi phenotyping by isoelectric focusing were performed for all patients. Positive IIF sera were tested in antigen-specific enzyme-linked immunosorbent assay: proteinase 3 (PR3), myeloperoxidase (MPO), lactoferrin (LF), lysozyme, human leucocyte elastase (HLE), cathepsin G and bactericidal/permeability increasing protein (BPI). RESULTS: Sixty-one patients with UC (64.2%) and only 11 with CD (17.5%) had ANCA (P < 0.001). Antigen specificities were PR3 (7/61), MPO (3/61), LF (6/61), HLE (1/63) and BPI (10/61) in UC, and PR3 (2/11) and BPI (2/11) in CD. Three PiZ alleles were found, matching the prevalence in the normal French control population. No relationship was found between the presence of ANCA, antibody specificity, disease activity and deficient alpha1-AT alleles. CONCLUSION: ANCA are more frequent in UC than CD and do not correlate with disease activity. ANCA and protease/antiprotease imbalance do not appear to modulate the clinical course of inflammatory bowel disease.     

Anti-neutrophil cytoplasmic antibodies (ANCA) in sera from patients with inflammatory bowel disease (IBD)

Anti-neutrophil cytoplasmic antibodies producing a perinuclear fluorescence pattern on ethanol-fixed granulocytes (p-ANCA) were found in 33 of 67 patients (49%) with ulcerative colitis (UC) but also in 14 of 35 patients (40%) with Crohn's disease (CD). In the latter condition p-ANCA were equally present in subgroups with colonic, ileocolonic, or ileal involvement only. Titers of p-ANCA were higher in patients with UC compared to CD patients, in particular when comparing patients with active disease. In contrast to findings in CD, patients with active UC had higher titers of p-ANCA than patients with inactive UC. Although p-ANCA were incidentally directed to lactoferrin, both in UC and CD, and to proteinase-3 and myeloperoxidase in UC only, the antigenic nature of p-ANCA could not be identified in most of the cases. We conclude that, within the spectrum of inflammatory bowel disease, the presence of p-ANCA is not specific for UC. When titers of p-ANCA are taken into account, the presence of high-titered p-ANCA, however, suggests active UC.     

Autoantibodies to neutrophil cytoplasmic (ANCA) and endothelial cell surface antigens (AECA) in chronic inflammatory bowel disease

Sera from 103 patients with chronic inflammatory bowel disease (IBD) were tested prospectively for antibodies against neutrophil cytoplasmic antigens (anti-neutrophil cytoplasm antibodies, ANCA) and endothelial cell surface antigens (anti-endothelial cell antibodies, AECA) by indirect immunofluorescence (IIF) and assays based on whole fixed neutrophils, purified neutrophil enzyme substrates and human umbilical vein endothelial cells. Using IIF, ANCA were found in 26 IBD sera (25%) and in none of 51 controls. Twenty-two positive sera (85%) were from patients with ulcerative colitis (UC). The pattern of distribution of immunofluorescence was always perinuclear (P-ANCA). A majority of UC patients positive for these autoantibodies (68%) had active colitis, but none had evidence of vasculitis. Using a whole neutrophil ELISA, binding was demonstrable in 73% of UC sera compared to 27% of Crohn's (CD) sera and only 4% of controls. Unlike vasculitis sera, UC sera with P-ANCA did not bind strongly to myeloperoxidase (MPO). Forty-five per cent of IBD sera tested positive for IgG AECA in an endothelial cell ELISA, compared to seven of 51 (14%) controls. Binding correlated with both active and extensive colitis. A type of P-ANCA, in most cases distinct from MPO-specific P-ANCA observed in vasculitis, is detected in a significant proportion of patients with UC, but rarely Crohn's colitis and therefore may be of differential diagnostic value. IgG AECA are also frequent in CIBD sera but are less disease specific than ANCA. (Aust NZ J Med 1992; 22: 652ndash;659.)     

抗嗜中性粒细胞胞浆抗体与狼疮性肾炎的关系

目的探讨抗嗜中性粒细胞胞浆抗体（ANCA）与狼疮性肾炎（LN）临床相关表现和发病机制的关系。方法分别应用间接免疫荧光法和酶联免疫吸附分析的方法,检测81例LN患者血清中的ANCA,并分析ANCA与LN临床表现和其它实验室检查结果之间的关系。结果单用间接免疫荧光法检测时,ANCA在LN中的阳性率是30.9％（25／81）。对间接免疫荧光法检测为阳性的血清,用酶联免疫吸附分析法进行验证,结果仅有72.0％（18／25）仍为阳性,全部是核周型ANCA（p-ANCA）,未见中央型ANCA（c-ANCA）出现。ANCA阳性组LN患者合并浆膜炎、神经系统累及、贫血、抗ds-DNA抗体阳性和低补体的频率均显著高于ANCA阴性组LN患者。结论ANCA在LN中的阳性率为30.9％,并与LN特定的临床表现相关,提示ANCA可能参与了LN的发病过程。     

Prevalence of antineutrophil cytoplasmic autoantibodies in patients with tuberculosis

OBJECTIVE: To determine the prevalence of antineutrophil cytoplasmic autoantibodies (ANCA) in sera of patients with tuberculosis compared with healthy control subjects and a group of patients with atopic asthma. METHODS: The presence of ANCA was examined in patients with tuberculosis, and in asthmatic patients and healthy subjects as control groups, by means of indirect immunofluorescence (IIF) and enzyme-linked immunosorbent assay (ELISA) to detect anti-proteinase 3 (PR3-ANCA) and antimyeloperoxidase (MPO-ANCA) antibodies. RESULTS: ANCA were present in 20 (44.4%) of 45 tuberculosis patients by IIF (16 c-ANCA, four p-ANCA) and in 18 (40%) patients by ELISA (15 PR3-ANCA, three MPO-ANCA). High odds ratios for ANCA positivity were observed for tuberculosis patients when compared with both control groups. ANCA results were not related to the category of tuberculosis, stage of disease, presence of concomitant diseases or pharmacotherapy. CONCLUSIONS: As many clinical similarities between tuberculosis and Wegener's granulomatosis exist, we propose that a positive ANCA test in patients living in countries with a high prevalence of tuberculosis must be carefully interpreted as indicative of systemic vasculitis, especially when no signs of extrapulmonary involvement occur.     

Impact of race and ethnicity on inflammatory bowel disease

INTRODUCTION: Inflammatory bowel disease (IBD) is now increasingly recognized in diverse ethnic populations. In the United States, IBD among the minority populations, especially Mexican Americans, has not been extensively studied. Apart from the known genetic influences that differ among the IBD subtypes [ulcerative colitis (UC) vs. Crohn's disease (CD)], serologic markers may differentiate UC and CD, including perinuclear antineutrophilic cytoplasmic antibody (p-ANCA) and anti-Saccharomyces cerevisiae antibody (ASCA) in UC and CD. METHODS: One hundred forty-eight patients with IBD seen in a university gastroenterology practice in Houston, Texas, between June 1999 and November 2003 were analyzed to determine whether there were significant differences among racial/ethnic groups. Whites comprised 40%, African Americans 37%, Mexican Americans 20%, and Asians 3% of the total IBD patients. RESULTS: We found that African Americans and whites predominantly had CD, whereas Mexican Americans predominantly had UC. There was no difference between African Americans and Mexican Americans when separately compared to whites in terms of intestinal manifestations of CD and UC, respectively. However, African Americans with CD had a significantly higher incidence of IBD-associated arthritis (p= 0.004) and ophthalmological manifestations, notably uveitis (p= 0.028), compared to whites with CD. Among UC patients, in comparison to the Mexican Americans, whites had significantly higher incidences of joint symptoms (p < 0.0001) and osteoporosis (p= 0.001). Whites had a stronger family history of IBD and colorectal carcinoma compared to the other ethnic groups. p-ANCA served as a sensitive marker for UC among Mexican Americans. All the Mexican Americans with UC tested had positive p-ANCA compared to only 40% of whites (p= 0.033). CONCLUSION: There are significant differences in IBD subtypes and serologic markers among racial/ ethnic groups with IBD in the United States.     

Phagocytosis, killing, lymphocyte-mediated antibacterial activity, serum autoantibodies, and plasma endotoxins in inflammatory bowel disease

OBJECTIVE: Alteration of mucosal and systemic immune responses may play an important role in the pathogenesis of inflammatory bowel disease (IBD). The aim of this study was to evaluate natural immune responses (i.e., phagocytosis, killing, and antibacterial activity), serum autoantibodies (antineutrophil cytoplasmic antibodies [ANCA] and anti-lactoferrin [LF] antibodies), and plasma endotoxins in patients affected by ulcerative colitis (UC) and Crohn's disease (CD). METHODS: Blood samples were obtained from 71 patients with UC, 32 patients with CD, and 32 control subjects. Disease activity was scored using Truelove's criteria in patients with UC and the Crohn's Disease Activity Index (CDAI) in patients with CD. Candida albicans served as a target for evaluation of phagocytosis and killing exerted by polymorphonuclear cells (PMN) and monocytes (MO), whereas Salmonella typhi was used for assessing lymphocyte-mediated antibacterial activity. ANCA were detected by indirect immunofluorescence, whereas anti-LF antibodies were assayed by means of enzyme-linked immunosorbent assay. Plasma endotoxins were measured by Limulus amoebocyte lysate assay. RESULTS: Phagocytosis and killing exerted by PMN and MO, as well as lymphocyte-mediated antibacterial activity, were significantly reduced (p < 0.0001) in patients affected by UC and CD in comparison with controls, irrespective of either disease activity or treatment. Plasma endotoxins were detected in 12/71 (17%) patients with UC, and in 10/32 (31%) patients with CD. ANCA were present in 42/71 (59%) patients with UC and in 3/32 (9%) patients with CD, whereas anti-LF antibodies were detected in 31 (44%) UC patients and in six (19%) CD patients. No significant differences in phagocytosis and killing exerted by PMN were found between ANCA-positive and ANCA-negative UC patients. CONCLUSIONS: Our data demonstrate an impairment of natural immunity exerted by peripheral blood phagocytes and lymphocytes in patients with UC and CD. ANCA and anti-LF antibodies were present mainly in UC patients but their presence did not affect PMN-mediated phagocytosis and killing. Finally, plasma endotoxins may contribute to the chronic inflammatory status, likely by inducing release of proinflammatory mediators.     

Prediction of relapses in Wegener's granulomatosis by measurement of antineutrophil cytoplasmic antibody levels: a prospective study

OBJECTIVE: Prediction of relapses in Wegener's granulomatosis (WG) by measuring levels of antineutrophil cytoplasmic antibodies (ANCA) directed against proteinase 3 (PR3) or myeloperoxidase (MPO) remains a controversial issue. To assess the value of serial quantification of ANCA by indirect immunofluorescence (IIF) and antigen-specific enzyme-linked immunosorbent assay (ELISA) for monitoring disease activity in patients with WG, a prospective observational study was conducted in patients with WG attending an outpatient clinic in the Netherlands. METHODS: One hundred patients with WG (85 with PR3-ANCA, 15 with MPO-ANCA) were studied prospectively from 1996 to 1998. Serum samples were obtained and analyzed every 2 months for ANCA levels. Disease activity was prospectively assessed without knowledge of the ANCA levels. RESULTS: Relapses occurred in 37 of 100 patients (37%). Thirty-four (92%) of the 37 patients showed a rise in the level of ANCA preceding their relapse, as detected by ELISA or IIF. The predictive value of an increase in ANCA titers for relapse was 57% (17 of 30) for cytoplasmic/classic ANCA (cANCA; by IIF), 71% (27 of 38) for PR3-ANCA (by ELISA), and 100% (3 of 3) for MPO-ANCA (by ELISA). The predictive value of a rise in ANCA as measured by ELISA or IIF did not substantially improve following concomitant measurement of the IgG3 subclass of PR3-ANCA. Forty-three percent of patients who showed a rise in cANCA (by IIF) and 29% with a rise in PR3-ANCA (by ELISA) did not subsequently experience a relapse. CONCLUSION: Serial measurement of ANCA levels is valuable for the early prediction of relapses in patients with WG.     

B-lymphocyte activating factor levels are increased in patients with Wegener’s granulomatosis and inversely correlated with ANCA titer

Circulating autoantibodies against neutrophils (ANCA) are a distinctive finding in patients with Wegener’s granulomatosis (WG). B-lymphocyte activating factor (BAFF) promotes autoantibody production by increasing B cell survival and proliferation. We investigated serum BAFF levels (s-BAFF) in a WG patient cohort in relation to ANCA titers and disease activity. Baseline data were obtained in twenty-two WG patients (55% female, age 44 years, disease duration 1 year). S-BAFF was determined by capture ELISA and associations between s-BAFF, clinical (Birmingham Vasculitis Activity Score (BVAS), Vasculitis Damage Index (VDI) and Disease Extent Index (DEI)) and biochemical (C-reactive protein (CRP), IgG and ANCA) disease measures were analysed in a cross sectional as well as longitudinal analysis. S-BAFF was increased in WG patients compared to healthy controls (1.8 vs. 0.55 ng/ml, p < 0.01). S-BAFF was higher in ANCA negative than ANCA-positive WG sera (2.16 vs. 1.29 ng/ml, p < 0.01), correlated independently and inversely with ANCA levels (Rs −0.48, p < 0.01) but did not correlate with CRP, BVAS, DEI or VDI scores. Individual s-BAFF profiles were stable over time in 68% of patients. The finding of a negative correlation between ANCA levels and s-BAFF that is independent of steroid treatment indicates that BAFF does not directly drive ANCA production in WG.     

High frequency of antigliadin antibodies and absence of antireticulin and antiendomysium antibodies in patients with ulcerative colitis

Several authors have described an association between celiac disease (CD) and ulcerative colitis (UC), but this has not yet been established. The aim of our study was to examine the frequency of antigliadin antibodies (AGA), antireticulin antibodies (ARA) and antiendomysium (AEM) antibodies in the sera of patients with UC (n = 50), and to evaluate their correlation with clinical variables. Sixteen patients with irritable bowel syndrome (IBS) and 37 healthy individuals served as controls. An enzyme-linked immunosorbent assay was used for the detection of IgA- and IgG-type AGA. IgG-type ARA were determined by an indirect immunofluorescence assay (IIF) using rat kidney, liver, and stomach as antigen substrates. IgA-type AEM antibodies were measured by IIF, using cryostat sections from human umbilical cord. Seventeen of the 50 patients with UC (34%) were positive for IgA- or/and IgG-type AGA. There was no correlation between the presence of AGA and the duration or extent of the disease, or disease activity. However, 5 patients with both IgA- and IgG-types of AGA had extensive colitis. Only 2 controls (4%) were positive for IgG-AGA. ARA and AEM were not detected in any individuals studied. Since the ARA and AEM test results were negative, we conclude that none of the UC patients in this series had CD. (Received Feb. 10, 1998; accepted July 30, 1998)     

Antineutrophil cytoplasmic antibodies (ANCA) and small vessel vasculitis

We report on one patient with Wegener's granulomatosis (WG) and two patients with microscopic polyangiitis (MPA). The patient with WG had signs of a respiratory infection and showed a c-ANCA pattern with proteinase 3 (PR3) specificity. The patients with MPA presented with pulmonary haemorrhage and signs of renal damage and showed a p-ANCA pattern with myeloperoxidase (MPO) specificity. In the three patients histopathological findings confirmed the diagnosis. We discuss the clinical indications of ANCA testing and the current terminology for reporting ANCA results (c-ANCA, p-ANCA, c-ANCA (atypical) and atypical ANCA). The target antigens and diseases associated with these different patterns are considered. Finally we focus on the value of ANCA and more specific PR3-ANCA and MPO-ANCA in the diagnosis of WG and MPA. The new application domain of ANCA in Crohn's disease and ulcerative colitis is also discussed.     

Interleukin-18 is increased only in a minority of patients with active Crohn’s disease

Background and aims It has been suggested that Crohn’s Disease (CD) is associated with an elevated T helper 1 response as manifested by increased production of interleukin-18 (IL-18). Local concentrations of neutralizing IL-18 binding proteins (IL-18bp) may counteract biological functions of mature IL-18 in mucosal inflammation. Therefore, we investigated the IL-18/IL-18bp system in a large group of patients with active inflammatory bowel disease (IBD) to identify patients that could respond theoretically to IL-18 neutralizing treatment strategies. Patient/methods IL-18 and IL-18bp messenger RNA (mRNA) expression in colonic mucosa from patients with active CD (n = 72), active ulcerative colitis (UC; n = 32), and non-IBD controls (infectious colitis or diverticulitis; n = 19) and normal, non-diseased controls (n = 20) were measured by reverse-transcribed real-time polymerase chain reaction. Mature IL-18 protein and IL-18bp expression in inflamed mucosa were assessed by Western blotting. Results/findings Although IL-18 mRNA was increased in some patients with CD, the increase was not statistically significant. Densitometric evaluation of IL-18/α-actin ratio in patients with active CD (n = 20) and patients with UC (n = 10) demonstrated an increased ratio of IL-18 protein in CD when compared to UC (1.04 vs 0.72 [median]). On closer inspections, only 7/20 CD patients had an increased IL-18 protein expression in inflamed areas compared to noninflamed mucosa. Interpretation/conclusion IL-18 expression in active CD is heterogeneous, only a minority of patients expresses elevated levels. Further treatment strategies targeting IL-18 expression in active CD should be concentrated on this subgroup of patients.     

Anti-neutrophil cytoplasmic antibodies (ANCA) in malaria

Various autoantibodies like anti-nuclear antibodies (ANA), anti-double stranded DNA (anti-dsDNA), anti-histone antibodies (AHA), anti-neutrophil cytoplasmic antibodies (ANCA), anti-myeloperoxidase (anti-MPO), anti-proteinase3 (anti-PR3) and anti-lactoferrin (anti-LF) antibodies were studied in 173 acute hospitalised patients suffering from malaria of which 160 patients had P. falciparum and remaining 13 had P. vivax infection. Standard methods like indirect immunofluorescence (IIF) microscopy along with Confocal microscopy and ELISA were used for identifying and quantifying the autoantibodies and IIF patterns on PMN and HL-60 cells were studied for ANCA classification. Also HEp-2 cells were used for ANA detection, while estimation of anti-dsDNA, AHA, anti-MPO, anti-PR3 and anti-LF were tested using ELISA. Sera from malaria patients showed prominent immunofluorescence staining patterns where 23.8% cases had ANA in P. falciparum group as compared to 15.4% in P. vivax group and ANCA was found to be present in 20% in P. falciparum and 15.4% in P. vivax group. An interesting observation was that, of the total ANCA positives, 59% had p-ANCA, 5.9% had c-ANCA and 44.1% of the cases showed the 'atypical' or X-ANCA pattern. When p-ANCA positivity was compared with c-ANCA positivity among these patients, a good statistical correlation was noted with OR = 16, chi 2 = 16.43, EF = 0.46 and p-value = 5.037E 0.5. ELISA showed 31.2% anti-MPO and 6.2% anti-PR3 in P. falciparum cases while the two ANCA positive cases in P. vivax had anti-MPO. Anti-LF was found to be present in 40.6% cases. Neither the P. falciparum nor P. vivax contained autoantibodies with specificities similar to the characteristic lupus autoantibodies such as double stranded DNA (dsDNA). ANCA positivity develops in some types of malarial infection also with the presence of various autoantibodies which is important from a clinical point of view and should be carefully evaluated in those geographic areas where malaria is endemic. It also alerts us to the fact, whether in cases of repeated malarial infections in susceptible individuals, vasculitic disorders, which through ANCA pathways develop, could lead to renal and other complications.