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A Wiik

Publications and source records attributed to A Wiik.

At least 19 recordsLinked to original sources
PubMed2006

European attempts to set guidelines for improving diagnostics of autoimmune rheumatic disorders.

The rational way to set a diagnosis and estimate a prognosis in rheumatology is to start by setting a tentative diagnosis and then follow a fixed scheme for laboratory testing, eg, by using an agreed algorithm. The use of order algorithms can be extended to post-test algorithms that will assist clinicians in approaching the right diagnosis and prognosis. New methods used in autoimmune serology do not deliver results that can be directly compared to those of older methods, and thus the new methods need to be thoroughly tested with sera from differential diagnostically relevant disease controls to set a clinically meaningful cut-off for positivity. Borderline positive results need to be treated with special care to avoid misuse. Early diagnosis is of great importance, and serological results can be very useful if used the right way. European efforts to secure rational diagnostic work-up in autoimmune rheumatic disease have led to a better dialogue between clinicians and laboratory scientists in several countries.

Algorithms↗
PubMed2005

CLL family 'Pedigree 14' revisited: 1947-2004.

The notion that inherited predisposition contributes to the development of haematological malignancies is generally thought of as being a relatively new idea. However, Videbaek made a clear enunciation of such a hypothesis in 1947, from a study of tumour incidence in relatives of patients with different leukaemias. To gain further insight into inherited susceptibility to chronic lymphocytic leukaemia (CLL), we followed up the descendants of Videbaek's 'Pedigree 14' series of families. Using the Danish medical and pedigree databases, complete tracing of 222 descendants of the original 57 family members was achieved. To date, 10 family members have been diagnosed with CLL, one with T-cell lymphoma and 17 with nonhaematological cancers, including five with breast cancer. The detailed follow up of this family provides further support for inherited predisposition to CLL and illustrates the value of follow-up studies of previously published family material for genetic analyses.

Aged↗
PubMed2005

Absence of high-affinity calreticulin autoantibodies in patients with systemic rheumatic diseases and coeliac disease.

Calreticulin has been reported to be an autoantigen in various autoimmune connective tissue diseases and in coeliac disease. Previous studies have used incubation buffers with low salt and low detergent concentrations (low stringency conditions) with serum albumin or other proteins as a blocking agent. Using these conditions we found a relatively high level of non-specific binding in many sera. Antibodies to proteins that are used as blocking reagents in ELISA (bovine serum albumin (BSA), ovalbumin, skimmed milk powder) are frequently present in sera, and these may cause false-positive results. Moreover, the low isoelectric point of calreticulin and its chaperone properties may give rise to false-positive results under low stringency conditions. We report that the use of a simple buffer without protein (50 mM Tris, pH 7.5, 1% Tween 20, 0.3 M NaCl) removes most of the problems with unwanted binding (high stringency conditions). Using the high stringency conditions, we screened sera from 107 patients with systemic lupus erythematosus, sera from patients with other systemic autoimmune diseases and from children with coeliac disease for the presence of high-affinity calreticulin autoantibodies by immunoblotting and ELISA. None of the sera contained high-affinity calreticulin antibodies. It is concluded that calreticulin is not a common autoantigen in patients with autoimmune connective tissue diseases or coeliac disease.

Autoantibodies↗
PubMed2005

Expression of oestrogen receptor alpha and beta is higher in skeletal muscle of highly endurance-trained than of moderately active men.

AIM: Two known oestrogen receptors (ERs), ERalpha and the recently cloned ERbeta, are expressed in the human skeletal muscle of both males and females. The effects of oestrogen and the role of ERs in skeletal muscle tissue are not well known. Oestrogen receptors and some of their target genes are involved in angiogenic processes. It was hypothesized that ERs are expressed at a higher level in a group with higher oxidative capacity, and that such an enhanced expression would parallel expression of the angiogenic factor -- vascular endothelial growth factor (VEGF). METHOD: Muscle biopsies were taken from vastus lateralis in 10 highly endurance-trained males and 10 moderately active males and analysed for the expression of ERs and VEGF. RESULTS: The major findings in the present study were the higher mRNA levels of ERalpha, ERbeta and VEGF in the highly endurance-trained than in the moderately active group. CONCLUSION: These data suggest that the greater mRNA expression of ERalpha and ERbeta and the oestrogen-associated angiogenic factor VEGF support the hypothesis of an involvement of ERs in the adaptation of skeletal muscle to endurance training.

Adolescent↗
PubMed2005

Anti-Saccharomyces cerevisiae and antineutrophil cytoplasmic antibodies as predictors of inflammatory bowel disease.

BACKGROUND AND AIMS: Several antibodies have been reported in the sera of patients with Crohn's disease (CD) and ulcerative colitis (UC). The most commonly described are anti-Saccharomyces cerevisiae mannan antibodies (ASCA) in CD and perinuclear antineutrophil cytoplasm antibodies (pANCA) in UC. Familial clustering of these antibodies has been described, suggesting they might be genetic markers. Our aim was to investigate the presence of these antibodies before the emergence of overt clinical manifestations. METHODS: Since 1980, the Israeli Defense Force (IDF) Medical Corps Serum Repository has stored serum samples obtained systematically from 5% of all recruits on enlistment, and from the same population on discharge from compulsory military service. We evaluated serum samples obtained from 32 subjects with CD and eight with UC before they were clinically diagnosed, along with samples from matched controls. RESULTS: ASCA were present in 10/32 (31.3%) CD patients before clinical diagnosis compared with 0/95 (0%) controls (p<0.001). None of the eight patients with serum samples available before diagnosis of UC were ASCA positive. ASCA was positive in 54.5% of patients after diagnosis of CD. The mean interval between ASCA detection and diagnosis was 38 months. In 90% of patients, antibodies were detected in the first available serum sample; therefore, measurements of the average time from the presence of ASCA to diagnosis may be even longer. pANCA were present in 2/8 (25%) patients with available sera before the diagnosis of UC. None of their 24 matched controls were positive (p = 0.014). CONCLUSIONS: ASCA and pANCA may predict development of inflammatory bowel disease years before the disease is clinically diagnosed.

Adult↗
PubMed2004

High prevalence of autoantibodies among Danish centenarians.

The aim of this study was to investigate the prevalence of organ and nonorgan specific autoantibodies in relation to disability and comorbidity in an unselected population of centenarians. A population-based survey of all persons living in Denmark who celebrated their 100th birthday during the period 1 April 1995 to 31 May 1996, a total of 276 persons, was undertaken. Participants underwent an interview, a physical examination and blood sampling. Organ specific autoantibodies (Tg-ab, TPO-ab, PCA-ab) and nonorgan specific autoantibodies (ANA, IgM RF, IgA RF, MPO-ab, c-ANCA, p-ANCA, oxLDL-ab, IgM ACA, IgG ACA, PR3-ANCA, histone-ab, SSA-ab, SSB-ab, Mit-ab) were measured, and comorbidity and disability (Katz Index of ADL) were registered. In all, 207 (75.0%) of 276 eligible subjects participated, and 148 agreed to blood tests. A large majority (79.3%) had at least one autoantibody detected. Organ specific autoantibodies were present in 32.1% of the centenarians. The high level of autoantibodies did not reflect an equally high level of overt autoimmune disease. While nonorgan specific autoantibodies were equally represented in less-disabled/disabled subjects as well as in subjects with low/high comorbidity, significantly fewer subjects with organ specific autoantibodies were found among less-disabled subjects or subjects with low comorbidity. Autoantibodies (both nonorgan and organ specific) are common in an unselected population of centenarians of today, but do not reflect an equally high level of overt autoimmune disease. Non-organ specific autoantibodies are evenly distributed irrespective of the level of disability or comorbidity, suggesting underlying, undiagnosed pathological processes which may be part of the processes involved in frailty.

Aged↗
PubMed2003

Silicate antibodies in Danish women with silicone breast implants.

OBJECTIVES: To use a new immunological assay to evaluate silicate antibody levels in women with and without silicone breast implants (SBIs). METHODS: Women (n=186) were identified through Danish population-based registers and categorized into six groups defined by prior breast surgery (breast implantation/breast reduction/no breast surgery) and by the presence or absence of prior hospital diagnoses of soft-tissue rheumatism (muscular rheumatism, ICD-8 codes 717.90 and 717.99). The women underwent blood tests, a silicate antibody assay and a clinical examination. Severity of rheumatic symptoms/signs was scored from 1 (none) to 5 (severe). RESULTS: The level of silicate antibodies was not significantly different between the three groups with prior soft-tissue rheumatism (P > 0.5), with the lowest value among women with SBIs. Among women who had no prior diagnosis of soft-tissue rheumatism, silicate antibody levels were highest in women with SBIs (P < 0.01). No significant correlations were observed between silicate antibody levels and symptom severity scores. CONCLUSIONS: Silicate antibodies were not consistently associated with SBIs and were not correlated with rheumatic symptoms. The clinical relevance of these antibodies remains questionable.

Adult↗
PubMed2003

Oestrogen receptor beta is expressed in adult human skeletal muscle both at the mRNA and protein level.

AIM: There are two known oestrogen receptors (ER), oestrogen receptor alpha (ERalpha) and the recently cloned oestrogen receptor beta (ERbeta). ERalpha mRNA has been detected in mouse, rat, bovine and human skeletal muscle. ERbeta mRNA has been detected in bovine skeletal muscle. To our knowledge, no study has investigated the expression of oestrogen receptor beta in human skeletal muscle. Therefore, the primary aim of the present investigation was to study ERbeta mRNA and protein expression in human skeletal muscle. In addition the ERalpha expression was also studied. METHODS: Muscle biopsies were taken from vastus lateralis in six healthy adults (three women and three men). mRNA expression was detected with real-time PCR (TaqMan) and protein localization by immunohistochemistry. RESULTS: A clear expression of ERalpha and ERbeta mRNA was seen in skeletal muscle in all subjects. The ERalpha mRNA expression was 180 fold higher compared with that of ERbeta mRNA. Immunohistochemistry demonstrated positive staining for ERbeta, but not for ERalpha, with localization to the nuclei of skeletal muscle fibres. On average, 70% of all nuclei were ERbeta-positive. CONCLUSION: The present study shows for the first time ERbeta mRNA and protein expression in human skeletal muscle tissue in both males and females.

Adult↗
PubMed2003

The association of antinuclear antibodies with organ involvement and survival in systemic sclerosis.

OBJECTIVES: To study the frequency and specificity of antinuclear antibodies (ANA) and their association with internal organ involvement and survival in systemic sclerosis (SSc). METHODS: Sera from 276 SSc patients were analysed by an indirect immunofluorescence (IIF) technique with HEp-2 cells as a substrate to categorize centromeric (ACA), nucleolar, speckled and homogeneous nuclear IIF patterns. Specific ANA were determined as follows: anti-DNA topoisomerase I (anti-topo I) by double immunodiffusion, anti-U1 RNP by passive haemagglutination, anti-RNA polymerase I, II and III (anti-RNAP) and anti-histone (AHA) antibodies by enzyme immunoassays. During the follow-up of 7.0+/-4.5 (mean+/-S.D.) yr the occurrence of clinical manifestations and internal organ involvement was registered. RESULTS: ANA were present in 84% of the patients. The most common patterns of the IIF were speckled (41%), homogeneous (25%), nucleolar (24%) and centromeric (18%). A nucleolar pattern was associated with pulmonary fibrosis (P < 0.01) and cardiomegaly (P < 0.05). ACA were related to organic vasculopathy (P < 0.05) and renal involvement (P < 0.01), but not to pulmonary fibrosis (P < 0.01). Anti-topo I were present in 9.4%, anti-U1 RNP in 21%, anti-RNAP in 22% and AHA in 16% of the patients. Pulmonary involvement was more common in patients with anti-topo I (P < 0.05), whereas AHA-positive patients were characterized by cardiac (P < 0.05), pulmonary (P < 0.05) and renal (P < 0.05) involvement. A nucleolar IIF pattern and AHA were both associated with a decreased survival [relative risk of death 1.71 (P < 0.05) and 2.36 (P < 0.01), respectively]. CONCLUSIONS: AHA and a nucleolar HEp-2 cell pattern may indicate critical organ involvement and predict a reduced survival in SSc patients.

Adult↗
PubMed2002

Expansion of CD5 - B cells in multiple sclerosis correlates with CD80 (B7-1) expression.

The pathogenetic role of autoantibodies in multiple sclerosis (MS) is uncertain. CD5+ B cells commonly produce autoantibodies, but CD5 expression has also been implicated in B-cell tolerance. We studied B-cell subsets, anti-myelin protein antibody-secreting cells in cerebrospinal fluid (CSF) and a panel of serum autoantibodies in patients with clinically isolated syndromes (CIS), suggestive of MS and patients with clinically definite MS (CDMS). Patients with CDMS had a higher percentage of CD5- B cells in CSF than did control subjects (P = 0.02). CIS patients with immunoglobulin G (IgG) oligoclonal bands in CSF or multiple lesions on magnetic resonance imaging (MRI) had a higher percentage of CD5- B cells in CSF than did the remaining CIS patients (P = 0.03). The percentage of CD5- and CD80+ B cells correlated positively and the percentage of CD5+ B cells correlated negatively with the number of CSF cells secreting anti-myelin basic protein (anti-MBP) antibodies. The prevalence of serum autoantibodies was comparable in the three patient groups. We conclude that intrathecal expansion of CD5- B cells appears to be more characteristic in MS patients, and CD5+ B cells may be associated with a lower prevalence of anti-myelin antibody production.

Adult↗
PubMed2001

Prevalence and clinical significance of antikeratin antibodies and other serological markers in Lithuanian patients with rheumatoid arthritis.

OBJECTIVES: To assess the clinical value of several serological markers in Lithuanian patients with rheumatoid arthritis (RA) compared with control patients with rheumatic disease and age matched healthy controls. METHODS: Serum samples from 96 patients with RA of approximately 8 years' duration, 90 rheumatic disease controls, and 37 healthy subjects were tested. Antikeratin antibody (AKA), antineutrophil cytoplasmic antibody (ANCA), and antinuclear antibody (ANA) titres were estimated by indirect immunofluorescence (IIF) and serum samples positive for ANA and ANCA were further studied by enzyme linked immunosorbent assay (ELISA). IgA and IgM rheumatoid factors (RF) were measured by ELISA. RESULTS: A positive AKA test was highly specific for RA (diagnostic specificity 97%), being found in 44% of the patients. Although both RF tests had a higher sensitivity, they were less specific for RA. ANCA was detected in 33% of patients with RA but lacked diagnostic specificity. AKA and ANCA were associated with more erosive disease and the presence of extra-articular manifestations. Positivity for AKA, IgA RF, and ANCA was significantly associated with disease activity and worse functional capacity. However, in multiple regression analysis only positivity for AKA was significantly correlated with functional disability (p=0.0001), evaluated by the Steinbrocker functional classification, and no single marker had any relation with radiological damage. CONCLUSION: Although AKA showed the highest disease specificity, all serological markers studied except ANA exhibited interesting associations with important clinical and paraclinical parameters of RA.

Adult↗
PubMed2001

Anti-neutrophil cytoplasmic antibodies tests: which tests should be used in practice?

Serological testing for anti-neutrophil cytoplasmic antibodies (ANCA) has become an important tool for supporting a diagnosis of systemic necrotizing small vessel vasculitis: Wegener's granulomatosis, microscopic polyangiitis, Churg-Strauss syndrome and oligo-symptomatic forms of these. These so-called ANCA-associated vasculitides most often necessitate the institution of therapies with cytotoxic as well as anti-inflammatory agents, and hence, a firmly established diagnosis is mandatory to avoid unnecessary and risky treatment. In the laboratory of today the most appropriate way to detect the presence of vasculitis-associated ANCA is by using both indirect immunofluorescence and direct enzyme immuno-assay for antibodies to proteinase 3 and myeloperoxidase. The diagnostic specificity of these latter assays towards systemic vasculitis can only be secured by setting a suitably high cut-off value, chosen in collaboration with clinicians after testing carefully selected disease control sera. When classical cytoplasmic ANCA as well as a significant level of proteinase 3-ANCA are found in a given serum this combined result strongly indicates vasculitis. Similarly, the combination of perinuclear ANCA and a significant level of myeloperoxidase-ANCA is close to 100% specific for vasculitis.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed2001

Comparison of viral antibodies in 2 groups of patients with fibromyalgia.

OBJECTIVE: The etiologies of fibromyalgia (FM) are unknown. In some cases an acute onset following a flu-like episode is described; in other cases patients report slowly developing disease. We previously found increased prevalence of enterovirus IgM antibodies in patients with acute onset of FM compared to healthy controls. We looked for differences in antimicrobial IgM antibodies in acute versus nonacute onset FM. METHODS: Two well defined, comparable groups of patients with FM (acute 19, nonacute 20) were studied for antibodies in serum to an array of viruses including IgM antibodies. RESULTS: In most viruses no IgM antibodies were found. However, about 50% of the patients with acute FM onset had IgM antibodies against enterovirus compared to only 15% of the slow onset patients. CONCLUSION: The higher prevalence of IgM antibodies against enterovirus in patients with acute onset of FM may indicate a difference in the etiology or the immune response in these patients.

Acute Disease↗
PubMed2001

Laboratory diagnostics in vasculitis patients.

Anti-neutrophil cytoplasm antibodies are important markers of certain small vessel necrotizing vasculitides, but the optimal use of laboratory results in daily clinical practice necessitates collaboration between clinicians and laboratory specialists. Physicians must familiarize themselves with ANCA tests in ANCA-related vasculitides as well as in differential diagnostic patient populations in order to define cutoff values. Indirect immunofluorescence with a consensus-agreed technique combined with standardized enzyme immunoassays is the modality for detecting the main SSV-associated ANCA specificities using cutoff values that can sufficiently distinguish SVV from non-SVV patients. The combined use of IIF and direct EIA to demonstrate proteinase 3-ANCA and myeloperoxidase-ANCA at significant levels leads to a very high diagnostic specificity towards SVV conditions such as Wegener's granulomatosis, microscopic polyangiitis, Churg-Strauss syndrome, and limited forms of these such as renal-limited focal necrotizing glomerulonephritis. A strong reactivity of ANCA against several azurophil granule components indicates a drug-induced syndrome. ANCA-related SVV and drug-induced vasculitis or lupus syndromes have characteristic ANCA profiles that can help distinguish these conditions from other inflammatory diseases.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed2001

Influence of clinical features, serum antinuclear antibodies, and lung function on survival of patients with systemic sclerosis.

OBJECTIVE: To evaluate the independent contribution of several clinical and laboratory variables to the mortality of a cohort of Danish patients with systemic sclerosis (SSc). METHODS: A cohort of 174 patients with incident SSc was retrospectively identified using clinical charts and study records of all new patients with SSc. Disease onset was defined as the time of onset of cutaneous sclerosis. Vital status and causes of death were determined at the end of the observation period. Data on clinical status and pulmonary function were obtained. Antitopoisomerase I (anti-topo I), anticentromere, anti-U1-RNP, anti-U3-RNP, anti-Th-RNP, and anti-RNA polymerase (anti-RNAP) antibodies were determined by means of double immunodiffusion, immunofluorescence, hemagglutination technique, radioactively labelled antisense riboprobes, and ELISA, respectively. RESULTS: Patients were followed for a mean period of 13.3 yrs; 16 died of an SSc related condition and 50 of other causes. Pulmonary fibrosis, DLCO reduction < 40% of the expected, diffuse cutaneous involvement, SSc nephropathy, cardiac disease, and anti-topo I and anti-RNAP antibody were related to decreased survival due to SSc. Variables that entered a Cox regression model of SSc related mortality were right heart failure (RR 12.4, 95% CI 2.5-60), diffuse SSc (RR 7.8, 95% CI 1.8-35), SSc nephropathy (RR 6.1, 95% CI 1.8-21), and DLCO < 40% (RR 4.8, 95% CI 1.1-20). The relative risk of developing right heart failure and diffuse SSc given the presence of anti-RNAP antibody was 14 (p = 0.0001) and 1.9 (p = 0.01), respectively. The corresponding figures for anti-topo I antibody were 4.6 (p = 0.02) and 2.0 (p = 0.01). CONCLUSION: SSc related mortality was associated with right heart failure and diffuse SSc, both of which were also associated with the presence of anti-topo I and anti-RNAP antibody. The prognostic value of these autoantibodies may lie in the early course of the disease when specific morbidity has not yet evolved.

Adolescent↗