Antineutrophil Cytoplasmic Antibodies Testing Research Articles

Anti– Saccharomyces cerevisiae Antibodies Are Associated With the Development of Postoperative Fistulas Following Ileal Pouch-Anal Anastomosis

Although serologic testing for perinuclear antineutrophil cytoplasmic antibodies (pANCA) and anti-Saccharomyces cerevisiae antibodies (ASCA) is reportedly useful in distinguishing ulcerative colitis (UC) from Crohn's disease (CD), there are few and conflicting reports assessing their utility in predicting postoperative complications after ileal pouch-anal anastomosis (IPAA). We examined the associations between postoperative complications such as pouchitis or fistulas and pANCA and ASCA antibodies in a group of patients who underwent IPAA for UC. We conducted a retrospective chart review of 34 patients initially diagnosed with UC (four of these patients had a diagnosis of indeterminate colitis) who underwent IPAA by a single surgeon, and who had pANCA and ASCA antibody levels measured during their clinical course. Study patients were assigned to four groups based on the pattern of antibody reactivity: pANCA+/ASCA- (16 patients), pANCA-/ASCA+ (nine patients), pANCA+/ASCA+ (five patients), and pANCA-/ASCA- (four patients). The median length of follow-up was 16 months (3-144 months). None of the patients (0 of 16) who were pANCA+/ASCA- had their preoperative diagnosis of UC changed after a median follow-up of 14 months (3-118 months). Of the nine patients with a preoperative diagnosis of UC who were pANCA-/ASCA+, four patients (44%) had their diagnosis changed postoperatively to CD based on clinical findings, with a median follow-up: 15 months (5-98 months). Of 16 patients who underwent IPAA and who were pANCA+/ASCA-, 15 of 16 (93.75%), were free of fistulas postoperatively, with a median follow-up of 14 months (3-118 months). Of nine patients with a preoperative diagnosis of UC who underwent IPAA and who were pANCA-/ASCA+, four of nine (44%; p = 0.04) developed fistulas postoperatively, with a median length of follow-up of 55 months (15-67 months). No relationship between serologic profiles or antibody titer levels and the development of pouchitis was identified. In a cohort of patients undergoing IPAA for UC, serologic profiles may be useful in identifying patients at risk of postoperative fistula formation. Patients who were pANCA-/ASCA+ were at increased risk for the development of fistulas postoperatively compared to patients who were pANCA+/ASCA-, and were also more likely to have their diagnosis changed postoperatively to CD. A larger study is needed to validate these observations.

A 53-year-old female with haemoptysis following breast cancer resection

A 53-yr-old female presented with a 1-month history of cough productive of blood-flecked white sputum and right-sided chest pain. She had undergone a mastectomy 11 months previously for breast cancer. At surgery, the resection margins were free of tumour, lymph node sampling was negative, and no additional therapy was given. A chest radiograph at that time was normal. The patient’s medical history was otherwise remarkable for a remote seizure disorder, migraine headaches, and a 15 pack-yr smoking history without known lung disease. There was no history of fever or chills, weight loss, dyspnoea, sinus complaints, voice change, renal disease, distant travel or other provocative exposures. Examination disclosed a thin female in no distress. She was afebrile with a blood pressure of 130/70 mmHg, pulse of 104 beats·min-1, and respirations of 20 breaths·min-1. Apart from a left mastectomy scar, the examination was unremarkable with normal heart and lungs. There were no skin lesions, enlarged lymph nodes or abnormal neurological findings. Laboratory studies were remarkable for a leukocyte count of 10.2×109 cells·L-1, and normal haematocrit, renal function and serum calcium. Antineutrophilic cytoplasmic antibody testing was negative. An abnormal chest radiograph was obtained (fig. 1⇓). Fig. 1— Chest radiograph showing a) posterior–anterior view and b) lateral view. The …

Wegener’s Granulomatosis: A Review of the Clinical Implications, Diagnosis, and Treatment

Wegener’s granulomatosis is an autoimmune disorder that results in inflammatory reactions, necrotizing vasculitis and granulomatous lesions in various tissues and organs of the body. In Wegener’s granulomatosis, the upper respiratory tract, lungs, and kidneys are typically involved early in the course of the disease. Microscopic examination of biopsied tissue from an involved organ and the antineutrophil cytoplasmic antibody test (cANCA) are the most reliable diagnostic tests for Wegener’s granulomatosis. Early diagnosis and treatment (ie, combination of cyclophosphamide and prednisone) are imperative in WG since it is an almost invariably fatal condition if left untreated.

Endocarditis associated with antineutrophil cytoplasmic antibodies: a case report and review of the literature

We report a case of subacute bacterial endocarditis associated with small vessel vasculitis and a strongly positive cytoplasmic antineutrophil cytoplasmic antibody (c-ANCA) test. It is important to recognize this cause of positive c-ANCA because infectious endocarditis may closely mimic the clinical manifestations of ANCA-associated vasculitides such as Wegener granulomatosis or microscopic polyangiitis. Furthermore, ANCA-associated vasculitis may result in noninfectious endocarditis, which may be confused with bacterial endocarditis. In this paper, we review reported cases of ANCA-positive bacterial endocarditis and compare them to the reported cases of ANCA-associated idiopathic vasculitis with endocardial compromise.

Poor Renal Outcome of Antineutrophil Cytoplasmic Antibody Negative Pauci-immune Glomerulonephritis in Taiwanese

Pauci-immune glomerulonephritis (GN) is an important cause of crescentic GN, acute renal failure and mortality. However, data are limited on the clinical presentation and outcome in antineutrophil cytoplasmic antibody (ANCA) negative patients, especially in Asians. This retrospective study analyzed medical records and pathology slides of patients who received renal biopsy between February 1998 and October 2004. Enzyme-linked immunosorbent assay was used routinely for ANCA testing in all patients. Among 637 patients with biopsy-proven GN included in this study, 88 (13.8%) had glomerular crescent formation. Among them, pauci-immune crescentic glomerulonephritis (PICGN) (42 patients, 47.2%) and lupus nephritis (25 patients, 28.4%) were the most common pathologic diagnoses. Lupus patients were younger (p = 0.028), while PICGN patients had more chronic lesions (p < 0.001), extensive glomerular crescents (p < 0.001), less severe proteinuria (p < 0.001) and poorer renal survival (p = 0.0017). Among the PICGN patients, 62.5% had a positive ANCA test, 80% had myeloperoxidase-ANCA and 20% had proteinase-3-ANCA. Subgroup analysis showed that ANCA negativity was associated with less crescent formation (p < 0.001) but more chronic glomerular lesions (p < 0.001) and a trend toward worse renal outcome (p = 0.055). This study illustrates the necessity for pathologic diagnosis of pauci-immune GN despite ANCA negativity. The poor prognosis associated with ANCA negativity in this study may be partly due to delayed diagnosis since these patients frequently lacked systemic involvement.

Antineutrophil Cytoplasmic Antibodies and the Churg–Strauss Syndrome

Since testing for antineutrophil cytoplasmic antibodies (ANCA) became available for routine evaluation, no large homogeneous cohort of patients with the Churg-Strauss syndrome has been studied. To define the clinical and biological characteristics of newly diagnosed Churg-Strauss syndrome, according to the presence or absence of ANCA. Cross-sectional analysis of manifestations of participants who were enrolled in treatment trials between December 1995 and December 2002. Multicenter study in 63 clinical centers in France, Belgium, Latvia, and the United Kingdom, coordinated by the French Vasculitis Study Group. 112 patients with Churg-Strauss syndrome that was recently diagnosed on the basis of current classifications. The authors compared principal demographic, clinical, and laboratory features according to ANCA status at diagnosis. The authors detected ANCA in 43 (38%) patients. Positive ANCA status at diagnosis was associated with renal involvement, peripheral neuropathy, and biopsy-proven vasculitis, whereas negative ANCA status was associated with heart disease and fever. The authors assessed ANCA by immunofluorescence, but they did not assess ANCA centrally or systematically retest if ANCA was undetected at diagnosis. Phenotypically, ANCA-positive and ANCA-negative Churg-Strauss syndrome might differ. The association of ANCA positivity with clinical symptoms that indicate inflammation and necrosis of small vessels might characterize a predominantly vasculitic pattern of the Churg-Strauss syndrome.

Case 31-2005

A 60-year-old man was evaluated at the hospital because of renal failure. He had been well until a trip to Colorado three months earlier; one week after returning he reported fatigue, edema, and a rash on his arms and legs. Laboratory evaluation revealed anemia, renal insufficiency, microscopic hematuria, and proteinuria. Serum complement levels were decreased. A skin biopsy showed leukocytoclastic vasculitis. Testing for cryoglobulins and antineutrophil cytoplasmic antibodies was negative. A diagnostic procedure was performed.

A novel capture-ELISA for detection of anti-neutrophil cytoplasmic antibodies (ANCA) based on c- myc peptide recognition in carboxy-terminally tagged recombinant neutrophil serine proteases

Testing for antineutrophil cytoplasmic antibodies (ANCA) reacting with proteinase 3 (PR3) is part of the routine diagnostic evaluation of patients with small vessel vasculitis. For PR3-ANCA detection, capture ELISAs are reported to be superior to direct ELISAs. Standard capture ELISAs, in which PR3 is anchored by anti-PR3 monoclonal antibodies (moAB), have two potential disadvantages. First, the capturing moAB may compete for epitopes recognized by some PR3-ANCA, causing occasional false-negative results. Second, the capture of recombinant PR3 mutant molecules becomes unpredictable as modifications of specific conformational epitopes may not only affect the binding of PR3-ANCA, but also the affinity of the capturing anti-PR3 moAB. Here, we describe a new capture ELISA, and its application for PR3-ANCA detection. This new assay is based on the standardized capture of a variety of different carboxy-terminally c- myc tagged recombinant ANCA target antigens using anti-c- myc coated ELISA plates. Antigen used include c- myc tagged human rPR3 variants (mature and pro-form conformations), mouse mature rPR3 and human recombinant neutrophil elastase. This new anti-c- myc-capture ELISA for PR3-ANCA detection has an intra- and inter-assay coefficient of variation of 3.6% to 7.7%, and 15.8% to 18.4%, respectively. The analytical sensitivity and specificity for PR3-ANCA positive serum samples were 93% and 100%, respectively when rPR3 with mature conformation was used as target antigen, and 83% and 100% when the pro-enzyme conformation was employed. In conclusion, this new anti-c- myc capture ELISA compares favorably to our standard capture ELISA for PR3-ANCA detection, enables the unified capture of different ANCA target antigens through binding to a c- myc tag, and allows capture of rPR3 mutants necessary for PR3-ANCA epitope mapping studies.

Goodpasture Syndrome

Goodpasture Syndrome

A Comparative Study of Goblet Cell and Pancreatic Exocine Autoantibodies Combined with ASCA and pANCA in Chinese and Caucasian Patients with IBD

The incidence of Crohn's disease (CD) and ulcerative colitis (UC) is increasing, but differentiating between them is often extremely difficult. Pancreatic (PAB) and goblet cell autoantibodies (GAB) are specific for CD and UC, respectively, but with low sensitivity. In combination with anti-Saccharomyces cerevisiae (ASCA) and anti-neutrophil cytoplasmic antibodies (pANCA) testing, these antibodies may improve differentiation between the diseases. This study determined the sensitivity, specificity, and positive and negative predictive values (PPV and NPV) of PAB and GAB +/- ASCA and pANCA testing in Chinese and Caucasian IBD populations. Patients were recruited from Caucasian and Chinese populations (CD, n = 100; UC, n = 99; controls, n = 100). PAB was highly specific for CD, and detection was greater in patients less than 35 years old and in Chinese compared with Caucasian patients with CD (CD, 46% versus 22%, P = 0.018; UC, 2% versus 6%; controls, 0% versus 2%). GAB detection was poor in all groups (<2%). PAB showed a PPV of 93% to differentiate all patients with CD from patients with UC, but only 62% for those with isolated colonic disease. The PPV of PAB increased to 100%, specificity was 100%, and sensitivity was 21% for isolated colonic disease when combined with pANCA and ASCA. PAB expression was not associated with stricturing or perforating CD. This study identified that GAB was not useful in our patients with IBD. PAB expression was highly specific for CD and more sensitive in Chinese than Caucasian patients with CD. The combination of PAB, pANCA, and ASCA testing improved the differentiation between UC and CD, particularly in isolated colonic disease, compared with pANCA and ASCA testing alone.

Wegener’s granulomatosis mimicking a parotid abscess

We present the case of a previously healthy 59-year-old man who was under treatment for scleritis and episcleritis when he developed a parotid-gland swelling and pus-producing sinus. On surgical exploration, the features were those of a parotid abscess, but the lesion not only failed to heal post-operatively but increased in size very significantly. There was also severe necrotizing keratitis of the eyes. Due to clinical suspicion and a positive antineutrophil cytoplasmic antibodies test, Wegener's granulomatosis was diagnosed and the patient successfully treated with cyclophosphamide and steroids. Previously, a number of cases of Wegener's granulomatosis causing salivary-gland swelling have been reported in the literature; this is the first case in which the disease has masqueraded as a parotid abscess.

Granulomatose de Wegener

A granulomatose de Wegener caracteriza-se por vasculite necrosante granulomatosa que acomete preferencialmente vias aéreas superiores, inferiores e rins. Seu diagnóstico é feito associando-se as manifestações clínicas, radiológicas (multiplos nódulos escavados) e os achados anatomopatológicos e o anticorpo anticitoplasma de neutrófilos positivo. O tratamento com corticosteróides e ciclofosfamida leva a 90% de remissão da doença em 1 ano.

What do antineutrophil cytoplasmic antibodies (ANCA) tell us?

Antineutrophil cytoplasmic antibodies (ANCA) are autoantibodies directed against antigens found in the cytoplasmic granules of neutrophils and monocytes. ANCA testing is usually performed to help diagnose or exclude Wegener's granulomatosis and microscopic polyangiitis. The three most commonly used assays are indirect immunofluorescence (IIF) and the direct and 'capture' enzyme-linked immunosorbent assays (ELISAs) for ANCA directed against proteinase 3 (PR3) and myeloperoxidase (MPO). Although the International Consensus Statement for Testing and Reporting ANCA recommends that all sera are screened for ANCA by IIF and that IIF-positivity is confirmed by direct ELISAs, some laboratories test by direct ELISA alone, others screen with direct ELISA and confirm positive sera by IIF, and a few use capture ELISAs. This chapter discusses the various forms of vasculitis associated with ANCA, the usefulness of each of the ANCA assays and how ANCA testing can be used in the management of patients with small-vessel vasculitis.

Wegener’s granulomatosis presenting as renal mass: A case for nephron-sparing surgery

Wegener’s granulomatosis (WG) is a systemic disease well recognized by physicians. The upper and lower respiratory symptoms associated with the disease are easily recognized; however, its presentation as a solid renal mass is underappreciated. We present a case of a 61-year-old man who presented with a 5.2-cm renal mass diagnosed as WG after nephron-sparing surgery. The patient presented with mild symptoms suggestive of WG, but the antineutrophil cytoplasmic antibody test was negative. The renal mass and concerns about possible malignancy obscured the diagnosis of WG. This case illustrates that WG should be considered in the differential diagnosis of solid renal masses.

ANCA: Serology in Wegener′s granulomatosis

Wegener's granulomatosis (WG) is being increasingly diagnosed in India, which exists in two forms, the 'limited Wegener's granulomatosis' (LWG) having upper respiratory tract (URT) and lower respiratory tract (LRT) involvement and the 'classical Wegener's granulomatosis' (CWG), with the triad of URT, LRT involvement along with kidney involvement. Cytoplasmic ANCA (C-ANCA) or anti-Proteinase3 (anti-PR3), which is highly diagnostic for WG, rarely perinuclear ANCA (P-ANCA) may exist. To detect anti-neutrophil cytoplasmic antibodies (ANCA) and correlate it with serological, hematological parameters, and the Birmingham Vasculitis Activity Score (BVAS). Twenty-three clinically and histopathologically proven WG (16 CWG, 7 LWG) were studied. C-ANCA and P-ANCA patterns were identified by immunofluorescence and specificities were confirmed by 'alpha granule' enzyme linked immunosorbent assay (ELISA), anti-PR3, anti-MPO (myeloperoxidase) and anti-Lactoferrin (anti-LF) by ELISA. LRT involvement was seen in 91.3%, URT in 78.3%, and renal manifestations in 69.6% cases. The BVAS in CWG was significantly higher than BVAS in the LWG. Decreased hemoglobin, increased WBC counts, ESR, CRP and Creatinine were seen in CWG as compared to LWG. The C-ANCA was present in 65.2% patients and P-ANCA in 13% cases. Anti-PR3 was seen in 69.6% patients and anti-LF in 17.4% cases. Severity of disease and ANCA was higher in CWG than in LWG. Vasculitis syndromes are known to overlap and many go undetected; therefore ANCA testing, along with the clinical and histopathological observations may be helpful in early detection and management of WG cases.

Microscopic polyangiitis sparing the kidneys in a long-term survivor after allogenic bone marrow transplantation and graft-versus-host disease

We report an unusual case of microscopic polyangiitis sparing the kidneys in a long-term survivor of allogenic bone marrow transplantation. Clinical and pathologic studies revealed cutaneous leukocytoclastic vasculitis and isolated pulmonary capillaritis. Serological studies revealed "double positive": perinuclear antineutrophil cytoplasmic (p-ANCA) antibody testing with anti-myeloperoxidase (MPO) activity and anti-glomerular basement membrane (anti-GBM) antibody. The vasculitis has been successfully controlled with prednisone and cyclophosphamide.

Low seroprevalence and poor specificity of antineutrophil cytoplasmic antibodies in tuberculosis

Recently published findings suggested that antineutrophil cytoplasmic antibodies (ANCA), particularly those with a cytoplasmic (C-ANCA) labelling pattern and targeting proteinase 3 (anti-PR3), might be markers of tuberculosis (TB). This is a critical issue, because C-ANCA/anti-PR3 were considered to be a highly specific hallmark of Wegener's granulomatosis or microscopic polyangiitis and because TB may clinically mimic Wegener's granulomatosis. We therefore undertook a study with the aim of investigating further the prevalence and specificity of ANCA in TB. We evaluated serum samples from 67 patients diagnosed with culture-proven TB and 10 previously untested control samples from patients known to be ANCA positive (four Wegener's granulomatosis and two microscopic polyangiitides) or negative. All 77 sera were screened for ANCA using commercially available indirect immunofluorescence (IIF) and enzyme-linked immunosorbent assay (ELISA) for anti-PR3 and antimyeloperoxidase (MPO). IIF-positive and anti-PR3- and anti-MPO-negative sera were also tested for bactericidal/permeability-increasing protein, lactoferrin, elastase and cathepsin G specificities with commercially available ELISA. IIF detected ANCA in seven (10%) of the TB sera, including three C-ANCA and four atypical perinuclear-labelling ANCA. Only one IIF-negative specimen was anti-PR3 positive in ELISA. ANCA testing of the control sera yielded IIF and ELISA results concordant with previous findings, except for one borderline ELISA. Our results indicate that TB is associated with low ANCA seroprevalence and poor specificity, with no test serum showing combined C-ANCA/anti-PR3 activity. In a clinical setting of Wegener's granulomatosis/TB mimicry, such combined reactivity would seem to be more suggestive of Wegener's granulomatosis.

Use of Immunofluorescence and Confocal Laser Scanning Microscopy in Identifying Rare Cases of Anti-Neutrophil Cytoplasmic Antibodies (ANCA) Showing Dual Specificities to Myeloperoxidase and Proteinase3

Anti-neutrophil cytoplasmic antibodies (ANCA) are the immunodiagnostic markers for idiopathic necrotizing crescentic glomerulonephritis affecting mainly medium to small sized blood vessels. The diagnosis of ANCA associated vasculitis (AAV) is mainly based on clinical and histopathological characteristics along with the serological evidence. Immunofluorescence microscopy (IIF) is considered as the "gold standard" for ANCA detection, and ANCA showing two major patterns ie, cytoplasmic (c-ANCA) and perinuclear (p-ANCA) react with different antigenic targets of neutrophils like Proteinase3 (PR3) and Myeloperoxidase (MPO). A third unusual and rare immunofluorescence pattern called as "X- ANCA" or atypical ANCA is also sometimes seen. The difficulty in identification of ANCA immunofluorescence patterns is mainly seen due to the rare dual patterns seen in the same sera and also the additional nuclear immunofluorescence seen due to presence of anti-nuclear antibodies. ANCA testing by immunofluorescence and Confocal Laser scanning microscopy, as well as by specific ELISAs for detection of anti-PR3 and anti-MPO antibodies have helped in improving the diagnosis. Patients having dual specificities to MPO and PR3 in a patient is a rare finding. Among 425 clinically and histopathologically proven cases of AAV, eight patients (1.9%) had dual specificities, of which five patients showed mixed immunofluorescence pattern and 3 patients showed X-ANCA pattern which was confirmed by both immunofluorescence and Confocal Laser scanning microscopy and the dual specificities to MPO and PR3 were detected by individual ELISAs.

Evaluation of patients with scleritis for systemic disease

Objective To evaluate the relationship between associated medical conditions and scleritis—particularly, the timing of the diagnosis of these diseases. Design Retrospective case series. Participants Patients with scleritis presenting to a single center over an 18-year period. Methods Medical records were reviewed for the presence of an associated infectious or rheumatic disease and for the timing of the diagnosis of the systemic disease relative to the presentation for evaluation of the scleritis. Main outcome measures Presence of an associated medical condition and timing of diagnosis relative to that of scleritis. Results In a series of 243 patients with scleritis, 44.0% had an associated medical condition: 7.0%, an infection, and 37.0%, a rheumatic disease. The most frequent infection was herpes zoster, and the most frequent rheumatic disease was rheumatoid arthritis, present in 4.5% and 15.2% of patients, respectively. Of the 107 patients with an underlying disease, 77.6% had a previously diagnosed disease, 14.0% had their conditions diagnosed as a result of the initial evaluation, and 8.4% developed a systemic disease during follow-up. Systemic vasculitis was less likely to have been previously diagnosed than other rheumatic diseases (59.1% vs. 83.8%, P = 0.015) and more likely to be diagnosed by the initial diagnostic evaluation (27.3% vs. 8.8%, P = 0.027). Ten patients (4.1%) had a positive antineutrophil cytoplasmic antibody (ANCA) test result without clinical evidence of a systemic vasculitis. Four of 5 patients with a positive cytoplasmic ANCA test result but no clinical evidence of systemic vasculitis required immunosuppressive drugs for control of the scleritis, whereas 1 of the 5 patients with a positive perinuclear ANCA test result required immunosuppressive drugs. Among patients with no evident systemic disease after the initial diagnostic evaluation, the rate of occurrence of a rheumatic disease was 4% per person-year. Conclusions Although associated systemic diseases are frequent among patients with scleritis, the majority are previously diagnosed. Systemic vasculitis is less likely than other rheumatic diseases to have been previously diagnosed. Because vasculitis is a potentially life-threatening disorder, it should be a focus of the diagnostic evaluation.

The effect of a symptom related “gating policy” on ANCA requests in routine clinical practice

Background: Most positive antineutrophil cytoplasmic antibody (ANCA) results are associated with non-vasculitic conditions, and guidelines have been proposed for the judicious use of this test. The outcome of applying similar...