A study of long-term morbidity associated with autosomal recessive polycystic kidney disease.
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Publications and source records attributed to J A Savige.
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BACKGROUND: The "classical" antineutrophil cytoplasmic antibody (C-ANCA) pattern seen on indirect immunofluorescence (IIF) is characterised by granular cytoplasmic staining showing central or interlobular accentuation, and is strongly associated with antiproteinase-3 antibodies (PR3-ANCA) and Wegener's granulomatosis. However, many laboratories report C-ANCA in the presence of any cytoplasmic IIF staining, regardless of pattern, which risks reducing the diagnostic value of this pattern. AIMS: To classify different cytoplasmic ANCA patterns and thus determine whether stringent application of the classical criteria for C-ANCA would produce better correlation between C-ANCA and (1) PR3-ANCA enzyme linked immunosorbent assay (ELISA) results; (2) a diagnosis of systemic vasculitis (including Wegener's granulomatosis). METHODS: 72 sera with cytoplasmic IIF collected over a two year period were analysed by IIF and a commercial PR3-ANCA ELISA kit. RESULTS: Three IIF patterns were defined: "classical/true" C-ANCA as described above (n = 27 (37.5%)); "flat" ANCA with homogeneous cytoplasmic staining (n = 21 (29%)); and "atypical" ANCA which included all other cytoplasmic patterns (n = 24 (33.5%)). Twenty five of the 27 true C-ANCA sera (92.5%) contained PR3-ANCA (p < 0.0001), but none of the 21 with flat ANCA and only one of the 24 with atypical ANCA. From clinical data on 23 of the 27 true C-ANCA positive patients, 20 (87%) had evidence of Wegener's granulomatosis or systemic vasculitis (p < 0.0001 v the other two patterns). However, none of 19 sera with flat ANCA and clinical data had evidence of systemic vasculitis. CONCLUSIONS: Restricting the term "c-ANCA" to the "classical" description of central/interlobular accentuation on IIF, will improve its correlation with PR3-ANCA positivity and a diagnosis of systemic vasculitis.
The basement membranes of the glomerulus, thyroid and adrenal all contain the Goodpasture antigen, the target of autoantibodies in antiglomerular basement membrane (GBM) disease. Antithyroid antibodies can be associated with antiGBM disease, and there have been occasional reports of antithyroid antibodies in Alport syndrome, an inherited kidney disease where the GBM lacks the Goodpasture antigen. The aim of this study was to determine how often antithyroid and antiadrenal autoantibodies occurred in antiGBM disease, Alport syndrome and a related condition, thin basement membrane disease (TBMD). Sera from patients with antiGBM disease (n = 19), Alport syndrome (n = 5) or TBMD (n = 13) were tested for antithyroglobulin, antithyroid microsomal and antiadrenal antibodies. Five of the patients with antiGBM disease (5/19, 26%, P NS) had antimicrosomal, and one had antithyroglobulin, antibodies (1/19, 5%, P NS). No patient with Alport syndrome had antithyroid antibodies. One with TBMD (1/13, 8%, P NS) had antithyroglobulin and antimicrosomal antibodies at titres of 1/400 and 1/25,600, respectively. Both patients with antithyroglobulin antibodies had previously been diagnosed with hypothyroidism. No one with antiGBM disease, Alport syndrome or TBMD had antiadrenal antibodies. Antithyroid microsomal antibodies do not occur significantly more often in patients with antiGBM disease than in normals, and antithyroid and antiadrenal antibodies are not associated with Alport syndrome or TBMD.
AIM: To describe the neutrophil fluorescent patterns produced by antineutrophil cytoplasmic antibodies (ANCA) with different antigen specificities, and by other auto- and alloantibodies. BACKGROUND: Most sera from patients with active generalised Wegener's granulomatosis result in diffusely granular cytoplasmic neutrophil fluorescence with internuclear accentuation (cANCA) and proteinase 3 (PR3) specificity. About 80% of the sera from patients with microscopic polyangiitis result in perinuclear neutrophil fluorescence with nuclear extension (pANCA) and myeloperoxidase (MPO) specificity, or a cANCA pattern with PR3 specificity. However, many different neutrophil fluorescence patterns are noted on testing for ANCA in routine immunodiagnostic laboratories. METHODS: Sera sent for ANCA testing, or containing a variety of auto- and alloantibodies, were studied. They were examined by indirect immunofluorescence according to the recommendations of the first international ANCA workshop, and for PR3 and MPO specificity in commercial and in-house enzyme linked immunosorbent assays (ELISA). RESULTS: Sera with typical cANCA accounted for only half of all neutrophil cytoplasmic fluorescence. Other sera had "flatter" fluorescence without internuclear accentuation, and the corresponding antigens included MPO and bactericidal/permeability increasing protein (BPI), but were usually unknown. Peripheral nuclear fluorescence without nuclear extension occurred typically when the antigens were BPI, lactoferrin, lysozyme, elastase, or cathepsin G. Most types of ANA were evident on ethanol fixed neutrophil nuclei. AntidsDNA, antiRo, and antilamin antibodies resembled pANCA. Antimicrobial and antiribosomal antibodies produced cytoplasmic fluorescence, and antiGolgi antibodies, a pANCA. Sera from patients with anti-smooth muscle antibodies were associated with cytoplasmic fluorescence. There was no neutrophil fluorescence with anti-skeletal muscle and anti-heart muscle antibodies, anti-liver/kidney microsomal, antithyroid microsomal, or antiadrenal antibodies. Alloantibodies such as antiNB1 typically resulted in cytoplasmic fluorescence of only a subpopulation of the neutrophils. CONCLUSIONS: The ability to distinguish between different neutrophil fluorescence patterns, and the patterns seen with other auto- and alloantibodies is helpful diagnostically. However, the demonstration of MPO or PR3 specificity by ELISA will indicate that the neutrophil fluorescence is probably clinically significant, and that the diagnosis is likely to be Wegener's granulomatosis or microscopic polyangiitis.
Bacterial and viral infections may be associated with the onset of a number of autoimmune diseases and relapses of these conditions. We describe a patient in whom there was a close temporal relationship between a suppurative wound infection and the onset of microscopic polyarteritis. The clinical features of this disease responded to treatment with high dose prednisolone and cyclophosphamide. The patient had several further infective episodes while being treated, but there were no disease exacerbations or relapses related to these. Anti-neutrophil cytoplasmic antibodies (ANCA) were never demonstrated in this patient. Thus while it is likely that the infection precipitated the onset of the systemic vasculitic illness, this occurred independently of ANCA.
In this study of antineutrophil cytoplasmic antibody (ANCA)-associated diseases, we determined the prevalence of other autoantibodies and the antigen specificities of ANCA. ANA were common, occurring in 7 of 36 (19%) patients with Wegener's granulomatosis, in 16 of 34 (47%) patients with microscopic polyarteritis, in 6 of 11 (55%) patients with segmental necrotising glomerulonephritis and in 8 of 18 (44%) of those with ANCA-associated systemic vasculitis without renal involvement. ANA were associated more often with pANCA and microscopic polyarteritis than with cANCA (P < 0.05). Patterns were speckled (n = 23), homogeneous (n = 10) or nucleolar (n = 4). Anticardiolipin antibodies were also common, occurring in 10 of 25 (40%) patients with Wegener's granulomatosis, in 8 of 14 (57%) patients with microscopic polyarteritis and in 6 of 18 (33%) of those with a systemic vasculitis. However, anticardiolipin antibodies did not correlate with the presence of ANCA in any of the disease groups. Anti-GBM antibodies were demonstrated in only 2 of 25 (8%) patients with Wegener's granulomatosis, in 1 patient with microscopic polyarteritis (1/14, 7%) and in 1 with segmental necrotising glomerulonephritis (1/11, 9%). All four patients with anti-GBM antibodies had either cANCA or pANCA. In the second part of the study, the target antigens of ANCA were determined in Wegener's granulomatosis, microscopic polyarteritis, systemic vasculitis, inflammatory bowel disease, rheumatoid arthritis and systemic lupus erythematosus (SLE). Of the 19 sera with cANCA, 13 (68%) were directed against proteinase 3; other antigens were myeloperoxidase (1/19, 5%), elastase and lactoferrin together (1/19, 5%), lysozyme (1/19, 5%) or unknown (3/19, 16%). Of the 12 (58%) sera from patients with Wegener's granulomatosis who had cANCA, 7 bound to proteinase 3. Antimyeloperoxidase antibodies were present in 14 of 45 (31%) sera with pANCA; other antigens were proteinase 3 (5/45, 11%), elastase (3/45, 78%), lactoferrin (1/45, 2%), cathepsin G (5/45, 11%) or unknown (17/45, 38%). Antimyeloperoxidase antibodies were common in microscopic polyarteritis (6/14, 43%) and systemic vasculitis (5/16, 31%). However, the majority of target antigens in systemic vasculitis and rheumatoid arthritis with pANCA were not determined. "Atypical" ANCA were present in four patients, one with inflammatory bowel disease (1/8, 13%) and three with SLE (3/15, 20%). The specificities were cathepsin G, cathepsin G plus lactoferrin, or unknown in two sera. A recent report has suggested that bactericidal/permeability-increasing protein may be the target in patients with inflammatory bowel disease.
alpha 1-antitrypsin (alpha 1-AT) is a naturally occurring inhibitor of proteinase 3 (PR3) and elastase, two of the target antigens of anti-neutrophil cytoplasmic antibodies (ANCA). An increased incidence of alpha 1-AT phenotypes associated with dysfunctional alpha 1-AT or low serum levels has been reported in patients with anti-PR3 antibodies. We have studied the relationship between ANCA, and phenotypes and serum levels of alpha 1-AT. Phenotypes usually associated with a moderate or severe reduction in alpha 1-AT serum levels or in dysfunctional activity were found more often in individuals with anti-PR3 antibodies than in the general population: four of the 31 patients (13%) with anti-PR3 antibodies had phenotypes MZ (n = 2), S (n = 1) or Z (n = 1) (P < 0.05). However, the corresponding alpha 1-AT serum levels were normal (n = 3) or elevated (n = 1). None of the 31 sera with anti-PR3 antibodies had low levels of alpha 1-AT. No abnormal alpha 1-AT phenotype was demonstrated in seven patients with anti-elastase antibodies, despite a low level of alpha 1-AT in one serum. Anti-myeloperoxidase antibodies are common in patients with ANCA, but no abnormal phenotype or low serum alpha 1-AT level was demonstrated in any of 29 sera containing these antibodies. Finally anti-glomerular basement membrane (GBM) antibodies occur occasionally in patients with ANCA-associated diseases, but again none of 10 sera had an abnormal alpha 1-AT phenotype or low serum level. ANCA were not demonstrated by indirect immunofluorescence in any serum from 73 patients with abnormal alpha 1-AT phenotypes. These results confirm that patients with anti-PR3 antibodies often have alpha 1-AT phenotypes that are usually associated with low serum levels of alpha 1-AT or with dysfunctional protein. Nevertheless, the incidence of anti-PR3 antibodies in patients with abnormal alpha 1-AT phenotypes is very low. This probably reflects the rarity of Wegener's granulomatosis, the major disease associated with anti-PR3 antibodies, and the relative frequency of abnormal alpha 1-AT phenotypes. The mechanism for the development of anti-PR3 antibodies in patients with abnormal alpha 1-AT phenotypes is not clear, but may relate to the increased propensity of unbound and uninhibited PR3 to stimulate autoantibody production.
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Anti-neutrophil cytoplasmic antibodies (ANCA) are antibodies directed against enzymes that are found mainly within the azurophil or primary granules of neutrophils. There are 3 types of ANCA that can be distinguished by the patterns they produce by indirect immunofluorescence when tested on normal ethanol-fixed neutrophils. Diffuse fine granular cytoplasmic fluorescence (cANCA) is typically found in Wegener's granulomatosis, in some cases of microscopic polyarteritis and Churg Strauss syndrome, and in some cases of crescentic and segmental necrotising glomerulonephritis, but it is rare in other conditions. The target antigen is usually proteinase 3. Perinuclear fluorescence (pANCA) is found in many cases of microscopic polyarteritis and in other cases of crescentic and segmental necrotising glomerulonephritis. These antibodies are often directed against myeloperoxidase but other targets include elastase, cathepsin G, lactoferrin, lysozyme and beta-glucuronidase. The third group designated "atypical" ANCA includes neutrophil nuclear fluorescence and some unusual cytoplasmic patterns, and while a few of the target antigens are shared with pANCA, the others have not been identified. Sera that produce a pANCA or atypical ANCA pattern on alcohol-fixed neutrophils result in cytoplasmic fluorescence when formalin acetone fixation is used. pANCA or atypical ANCA occur in about 2/3 of all individuals with ulcerative colitis or primary sclerosing cholangitis, and they are found in a third of patients with Crohn's disease. The reported incidence of ANCA in rheumatoid arthritis and SLE varies considerably but the patterns are predominantly pANCA and atypical ANCA.(ABSTRACT TRUNCATED AT 250 WORDS)
Anti-proteinase 3 antibodies are a subgroup of anti-neutrophil cytoplasmic antibodies (ANCA), and we have established an ELISA for their detection using high performance liquid chromatography (HPLC)-purified protein. This assay is sensitive and specific: inhibition studies have shown that despite the homology between proteinase 3 and elastase there is no cross-reactivity between the corresponding antibodies for their targets. Anti-proteinase 3 antibodies were associated most often with cytoplasmic fluorescence (17/22, 77%), but occasionally with a perinuclear (3/22, 14%) or atypical pattern (1/2). These antibodies were found in 23 out of 76 sera (30%) that were positive in an ELISA based on a crude neutrophil cytoplasmic extract, and they were associated with both 29 and 55 kD bands on Western blots. Anti-proteinase 3 antibodies were found in most individuals with active Wegener's granulomatosis (10/13, 77%), but less often in individuals with microscopic polyarteritis (2/10, 20%) or segmental necrotizing glomerulonephritis (3/6, 50%). However, anti-proteinase 3 antibodies were not detected in any of 32 sera from individuals with rheumatoid arthritis or systemic lupus erythematosus (SLE). Occasionally anti-proteinase 3 antibodies were associated with anti-glomerular basement membrane antibodies (1/11, 9%) or with anti-myeloperoxidase antibodies (1/11, 9%). IgM anti-proteinase 3 antibodies were uncommon (2/22 sera, 9%), and no IgA antibodies were demonstrated in any of 22 sera from patients with active systemic vasculitis. Significantly more individuals presented with anti-proteinase 3 antibodies in April-May-June, suggesting that an infective agent prevalent in Autumn might have a causative role in the associated diseases. Anti-proteinase 3 antibodies are the most common target antigen associated with Wegener's granulomatosis and cytoplasmic fluorescence.
BACKGROUND: Anti-neutrophil cytoplasmic antibodies (ANCA) are typically associated with small vessel vasculitides. They are also found in situations where other autoantibodies are common, sometimes after infections and possibly in individuals who have received multiple blood transfusions. AIMS: The aim of this study was to determine the incidence of ANCA in a variety of haematological disorders, where these predisposing factors may be at work. METHODS: Sera from patients with myelodysplasia (n = 26), acute myeloid leukaemia (AML) (n = 3), and myeloproliferative (n = 25) or lymphoproliferative syndromes (n = 16) were screened for ANCA using a crude neutrophil cytoplasmic extract ELISA and indirect immunofluorescent examination of normal peripheral blood neutrophils. Positive results were confirmed by ELISAs for anti-proteinase 3, anti-myeloperoxidase or anti-elastase antibodies. RESULTS: ANCA were demonstrated in two patients with myelodysplasia, both with chronic myelomonocytic leukaemia and greater than 5% blasts in the bone marrow. Both of these individuals were infected at the time that ANCA were demonstrated and other autoantibodies were present. One of these individuals had never had evidence of any vasculitis; the other probably developed myelodysplasia after treatment with cyclophosphamide for Wegener's granulomatosis. ANCA were demonstrated in one individual with AML secondary to myelodysplasia. ANCA were also found in a patient with lymphoma in whom autoantibodies against red cells and platelets were already noted. ANCA were demonstrated in one further individual with lymphomatoid granulomatosis, a condition that resembles Wegener's granulomatosis clinically and histologically, but which is treated as a lymphoma. No ANCA were present in any of the patients with myeloproliferative syndromes. DISCUSSION: ANCA probably occur secondary to immune dysregulation in myelodysplasia and the lymphoproliferative conditions and they are not necessarily associated with the presence of a vasculitis.
Many autoantibodies have been described in HIV-infected individuals. We have examined the incidence, associations and prognostic significance of anti-nuclear antibodies (ANA), anti-neutrophil cytoplasmic antibodies (ANCA) and anti-glomerular basement membrane (GBM) antibodies in individuals with HIV infections. One hundred and five patients, with asymptomatic infections (n = 37), AIDS-related complex (n = 32) or AIDS (n = 36) were studied. Plasma from 24 of these (23%) were positive for ANA: most demonstrated speckled fluorescence (n = 21) and were of low titre (1+ in 18). ANCA were demonstrated by IIF in 18 individuals (17%) and all fluorescent patterns were seen; 6 of these plasma were also positive in the ELISAs for antibodies to proteinase 3, myeloperoxidase or elastase. Thirteen plasma were positive for ANCA in the neutrophil cytoplasm ELISA; 10 of these were also positive in the specific ELISAs. A total of 30 plasma bound to proteinase 3, myeloperoxidase or elastase in specific ELISAs, in 6 cases with 2 specificities. Finally, 18 plasma (17%) contained anti-GBM antibodies by ELISA, but none of 4 plasma tested in inhibition assays was specific. ANA, ANCA and anti-GBM antibodies were not uncommon in HIV-infected individuals but the presence of these antibodies was not associated with the clinical manifestations of the corresponding autoimmune diseases. In addition, there was no correlation between the demonstration of these antibodies and the immunological status of the individual (apart from a correlation between CD4 counts less than 400/microliters with anti-GBM antibodies), the presence of an opportunistic infection, the development of malignancy or reduced survival. Some of these antibodies may arise from polyclonal activation, or be due to "sticky" serum since we have shown that the presence of anti-GBM antibodies correlated with the demonstration of ANCA by ELISA. These antibodies are not more common in hypergammaglobulinemic plasma but some may be due to heat-treatment of the plasma. The clinician caring for HIV-infected individuals needs to be aware of these "false-positive" antibody results.
Sera from 105 HIV-infected patients were tested for anti-neutrophil cytoplasm antibodies (ANCA) by indirect immunofluorescence (IIF), by specific ELISAs using target proteins of ANCA and by a neutrophil cytoplasm extract ELISA. Forty-four sera were positive. These included 18 positive by IIF, 7 with anti-neutrophil proteinase 3 antibodies, 26 with anti-myeloperoxidase antibodies and 2 with anti-elastase antibodies. Four sera were positive in the neutrophil cytoplasm extract ELISA but not in the specific ELISAs. None of these patients had clinical evidence of a cutaneous or systemic vasculitis. In addition there was no correlation between the presence of ANCA and the stage of disease, intercurrent bacterial or viral infection, anti-nuclear antibodies (ANA) and positive hepatitis B or syphilis serology.
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A cutaneous or systemic vasculitis occurs in myelodysplasia as well as in myeloproliferative and lymphoproliferative disorders. The most common lesion is a leucocytoclastic vasculitis, with neurological or joint involvement occurring less often. The vasculitis may appear contemporaneously with or precede the clinical onset of the blood dyscrasia. Occasionally the lesions respond dramatically to the use of steroids but in general, patients with vasculitis have a worse prognosis than those with uncomplicated myelodysplasia. Vasculitis and myelodysplasia appear together too often for the association to be coincidental and the vasculitis in most cases cannot be attributed to intercurrent infections, therapeutic agents or a pre-existing rheumatological disorder. While autoantibodies are frequently present in myelodysplasia, and ANA and anti-neutrophil cytoplasm antibodies (ANCA) are found in other vasculitides, neither of these antibodies is associated with the vasculitis of myelodysplasia. There has however been one report of ANCA in Sweet's syndrome a non-vasculitic skin condition that also occurs in the myelodysplastic syndromes.
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Alport's syndrome is a heterogeneous group of inherited abnormalities of basement membranes that may result in progressive renal failure, defective hearing and lens abnormalities. The glomerular basement membrane (GBM) characteristically has areas of reduplication, lamellation and attenuation on electron microscopic examination. In the majority of affected males and some females, there is reduced or variable binding of serum from patients with anti-GBM disease (Goodpasture's syndrome) to these basement membranes. These sera contain antibodies directed against the Goodpasture antigen which has been thought to be located in the non-collagenous domain of the alpha3 chain of type IV collagen and is presumed to be important in cross-linking of the collagen molecules. The reduced staining for the Goodpasture antigen suggests that this structure is either absent or masked in Alport's syndrome. We have tested DNA from six unrelated individuals with Alport's syndrome. All had been transplanted for renal failure. The diagnosis of Alport's syndrome was made on the characteristic electron microscopic appearance of the renal basement membranes (n = 4), the presence of sensori-neural deafness (n = 4), a family history of Alport's syndrome (n = 5) and the presence of circulating inhibitable anti-GBM antibody activity post-transplant (n = 2). Oligonucleotides (20mers) corresponding to the 5' and 3' ends of the known 25 amino acid sequence for the putative Goodpasture antigen were used as primers for amplification of genomic DNA. The products were then blotted and probed with an intermediate 19-mer DNA. All Alport's patients contained a 75-bp fragment corresponding to the published peptide sequence for the non-collagenous domain of the alpha 3 chain of type IV collagen, suggesting that a large deletion of this region, the putative Goodpasture antigen, is unlikely to account for the defect in Alport's syndrome.