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A Linssen

Publications and source records attributed to A Linssen.

At least 19 recordsLinked to original sources
PubMed2001

Rhemulatologists' performance in dailiy practice.

OBJECTIVE: To assess rheumatologists' performance for 8 rheumatologic conditions and to explore possible explanatory factors. METHODS: After written informed consent was obtained, 27 rheumatologists (21% of all Dutch rheumatologists) practicing in 16 outpatient departments were each visited by 8 incognito "standardized patients" (SPs). The diagnoses of these 8 cases account for about 23% of all new referred patients in the Netherlands. Results for ordered lab tests as well as real radiographs with corresponding results from a radiologist were simulated. Information from the visits was obtained from the SPs, who completed predefined case-specific checklists, and by collecting data on resource utilization. Feedback was provided. RESULTS: Altogether 254 encounters took place, of which 201 were first visits and 53 were followup visits. SPs were unmasked twice during a visit. There was considerable variation in resource utilization (lab tests and imaging) between cases and between rheumatologists. Mean costs per rheumatologist ranged from US $ 4.67 to $ 65.36 per visit for lab tests and from US $ 33.15 to $ 226.84 per visit for imaging tests. No significant correlations were seen between resource utilization costs and number of years of clinical experience or performance on checklist scores. Rheumatologists with longer experience had lower total item checklist scores (r = -0.47; P < 0.05). CONCLUSION: A considerable variation in resource utilization was found among 27 Dutch rheumatologists. The information obtained is an excellent source for discussion on the appropriateness of care.

Adult↗
PubMed1995

Spondylarthropathy and selective IgA deficiency.

No serum IgA was detected in a young male patient suffering from spondylarthropathy (SpA) with bilateral sacroiliitis arthritis, enthesopathy and inflammatory low back pain, whose symptoms occurred in reaction to a sexually induced urethritis. After a period of several months in which the spondylarthropathy was active, disease activity came to a rest. Three years later no progression of the SpA was observed. This finding might be an indication that IgA is not involved in the pathogenesis of spondylarthropathy.

Adult↗
PubMed1995

Outcomes of HLA-B27-positive and HLA-B27-negative acute anterior uveitis.

PURPOSE: Outcomes of HLA-B27-positive and HLA-B27-negative acute anterior uveitis were assessed after a mean follow-up of nine years. Rheumatologic complications, in particular the presence and course of ankylosing spondylitis, were examined during the same period. METHODS: A hospital-based prospective study of 119 patients with HLA-B27-positive and 35 patients with HLA-B27-negative acute anterior uveitis was performed. All patients underwent a complete ophthalmologic and rheumatologic examination, including sacroiliac x-rays, and were examined again nine years later. RESULTS: No statistically significant differences in ocular complications and visual outcome were found between both patient groups with acute anterior uveitis after nine years. Posterior synechiae were observed in one half of the affected eyes. Blindness was infrequent. Rheumatologic complications, including ankylosing spondylitis, originally seen in one half of the HLA-B27-positive patients, were observed in two thirds of the patients nine years later, compared to only two of 35 HLA-B27-negative patients. When ankylosing spondylitis was evident at first examination no clinically significant deterioration was observed nine years later. CONCLUSIONS: After nine years we observed an ocular outcome equal for both patient groups. A small percentage of affected eyes became blind. Rheumatologic complications occurred in 55 (72%) of 76 HLA-B27-positive males and in 24 (56%) of 43 HLA-B27-positive females with acute anterior uveitis. The rheumatologic complications had a good prognosis.

Acute Disease↗
PubMed1992

Uveitis and systemic disease.

A prospective study was conducted of 865 patients with uveitis to determine the frequency of associated systemic diseases and to assess the value of limited laboratory screening of these patients. All patients underwent a standard diagnostic protocol followed--when indicated--by special tests and procedures performed in order of likelihood ('tailored approach'). For 628 patients (73%) a specific diagnosis was established based on history, ophthalmologic examination, and laboratory and radiographic studies. A definite association with systemic disease was determined for 220 patients (26%). A relationship with a subclinical systemic disorder could be presumed in 201 cases (23%) and a well-established clinical uveitis entity without a recognisable systemic disorder was present in 207 cases (24%). For 237 patients (27%) a diagnosis could not be determined. The most frequently observed systemic diseases were sarcoidosis (7%) and HLA-B27-associated seronegative spondylarthropathies (6%). Presumed or definite toxoplasmosis was encountered in 10% of cases. HLA-B27-associated acute anterior uveitis was the most common clinical entity (17%). In the majority of cases the presence of a systemic disease was not suspected prior to eye involvement and was only recognised after the subsequent diagnostic procedures.

Adolescent↗
PubMed1991

The lifetime cumulative incidence of acute anterior uveitis in a normal population and its relation to ankylosing spondylitis and histocompatibility antigen HLA-B27.

The lifetime cumulative incidence of acute anterior uveitis (AAU) was determined in a sample of a large population (n = 10,500). Nine hundred seventeen subjects, who answered the question "Have you ever had a red eye" in the affirmative in 1977, were asked to participate in a follow-up study 10 years later. From the 917 respondents, 539 were studied completely. A questionnaire was used to collect historic data, and confirmation of these data was obtained from the treating ophthalmologists and physicians. From these data, subjects were selected for an ophthalmologic examination. The respondents also underwent a rheumatologic examination. The results revealed that the lifetime cumulative incidence of definite AAU is approximately 0.2% in the general population and 1% in the histocompatibility antigen HLA-B27-positive population. In one third of the definite AAU patients, the cause of the disease was known. The lifetime cumulative incidence of definite AAU of unknown cause was 0.15% in the general population. When possible and probable AAU are included, the lifetime cumulative incidence of AAU in the general population is about 0.4%. The observed frequency of the concurrence of AAU and ankylosing spondylitis (AS) was 0.4% in the HLA-B27-positive population and 0.02% in the HLA-B27-negative population. Comparison with the expected frequency of the concurrence of AAU and AS revealed that AAU and AS probably are related diseases irrespective of the association of both diseases with HLA-B27.

Acute Disease↗
PubMed1990

B27+ disease versus B27- disease.

When studying heterogeneity of B27-positive disease versus B27-negative disease, very different patterns of disease associations but also a lot of similarities may be observed. In general, B27-positive disease has an earlier onset, a more severe and prolonged clinical course and is more often complicated by acute anterior uveitis and peripheral arthritis, whereas B27-negative disease is accompanied by psoriasis, inflammatory bowel disease and erythema nodosum in a higher percentage of the cases. Despite these differences, B27-positive disease may be completely undistinguishable from B27-negative disease in a number of individual cases. Family aggregation and male preponderance, however, are only seen in B27-positive disease. These observations may lead to the conclusion that HLA-B27 is probably not the only key to the pathogenesis of these diseases, but nevertheless an important genetic factor in disease expression.

Acute Disease↗
PubMed1988

A familial study of the inheritance of HLA-B27-positive acute anterior uveitis.

To determine whether factors besides HLA-B27 play a pathogenic role in acute anterior uveitis, we examined 152 first-degree relatives of 42 randomly selected HLA-B27-positive acute anterior uveitis patients. Nine relatives, all from different families, had acute anterior uveitis: eight were HLA-B27 positive and one was HLA-B27 negative. The prevalence of acute anterior uveitis in HLA-B27-positive first-degree relatives of HLA-B27-positive acute anterior uveitis patients was 13% (eight of 63). This is significantly more (P less than .0001) than the frequency of 1% in the normal HLA-B27-positive Dutch population. Ankylosing spondylitis was found in four of 38 (11%) HLA-B27-positive family members over the age of 45 years. This is also significantly more than the prevalence of 1% in a normal HLA-B27-positive Dutch population. Of these four relatives with ankylosing spondylitis, three also had acute anterior uveitis. It was remarkable that two of these four relatives had a proband who had no ankylosing spondylitis.

Adolescent↗
PubMed1988

Acute anterior uveitis and HLA-B27 subtypes.

The tissue antigen HLA-B27 is found in 50% of Dutch acute anterior uveitis (AAU) patients. The prevalence of HLA-B27 in the normal population is only 8%. However, only approximately 1% of HLA-B27+ individuals will develop AAU. Therefore, it is possible that the disease is associated with a particular B27 subtype. We typed lymphocytes of 36 B27+ AAU patients, of which 20 also had ankylosing spondylitis, for three serologically defined B27 subtypes (B27 W, B27 K and B27 non W/non K). These subtypes were normally associated with AAU. The subtype frequencies in the patients suffering from both AAU and AS also showed no preference for a certain subtype. Subtype-specific characteristics of the primary structure of the various B27 subtype molecules therefore cannot be responsible for the disease association.

Acute Disease↗
PubMed1987

Clinical features of acute anterior uveitis.

We studied the clinical features and prognosis of 73 patients with HLA-B27 positive and 71 patients with HLA-B27 negative acute anterior uveitis using computer analysis of more than 50 variables per patient. The patients with HLA-B27 positive acute anterior uveitis showed the following characteristics which were significantly different from patients with HLA-B27 negative acute anterior uveitis: younger age at onset; high male to female ratio; frequent unilateral alternating eye involvement; severe ocular symptoms during activity, such as presence of fibrin in the anterior chamber; absence of mutton fat keratic precipitates; high incidence of ocular complications; and frequent association with seronegative spondyloarthropathies. Despite the difference of disease severity and incidence of complications, the long-term visual outcome did not differ significantly between the two groups. No distinctions were observed when patients with HLA-B27 positive acute anterior uveitis were subdivided according to sex or the presence of ankylosing spondylitis. HLA-B27 positive acute anterior uveitis formed a distinct clinical entity associated with serious prognosis as compared to HLA-B27 negative acute anterior uveitis.

Acute Disease↗
PubMed1987

Genes on chromosome 14q and their role in the pathogenesis of HLA-B27 associated diseases.

Genetic factors other than HLA-B27 may play a role in the pathogenesis of ankylosing spondylitis (AS), acute anterior uveitis (AAU) and Reiter's syndrome (RS). Studies by Brewerton et al. and Kijlstra et al. showed associations between the MZ phenotype of alpha 1-antitrypsin and the Gm phenotype zafngb of IgG in patients with AAU, who developed AS. The loci for alpha 1-antitrypsin (PI) and Gm allotypes (IGH) are situated on the tip of the long arm of chromosome 14. In the present study we tried to clarify and extend the above studies. In 41 B27+ AAU patients with AS the alpha 1-antitrypsin and Gm phenotype and allotype frequencies were not statistically different from those in B27+ AS patients developing AAU and in B27+ AAU patients without AS, in B27+ AS patients without AAU, B27+ patients with Reiter's syndrome, B27+ patients with low back pain, B27- AAU patients and normal controls. It is therefore unlikely that genes on the tip of chromosome 14 play a role in the pathogenesis of B27 associated diseases. A hypothesis was formed suggesting that a bacterial-derived modifying factor may replace the position of beta 2 microglobulin in the HLA-B27 molecule resulting in an impaired cytotoxic T cell reactivity.

Alleles↗
PubMed1986

The use of HLA-B27 as a diagnostic and prognostic aid in acute anterior uveitis (AAU) in The Netherlands.

Acute anterior uveitis (AAU) may be considered to be one manifestation of the seronegative spondylarthropathies of which ankylosing spondylitis (AS) is the prototype, especially when the patient is HLA-B27 positive. However, it is not yet clear under which circumstances a patient with AAU should be referred to the rheumatologist. In a retrospective study we evaluated the management of 68 consecutive HLA-B27+ AAU patients from a rheumatologic point of view. Although the majority (73%) showed rheumatic problems, only half (52%) of the patients was referred to a rheumatologist, due to problems in evaluation of clinical history and of x-ray reading of the sacroiliac (SI) joints. Because HLA-B27 typing will determine whether the AAU patients "at risk" have AS or a related arthropathy, we suggest using HLA-B27 typing in AAU patients as a diagnostic and prognostic aid. When the AAU patient is found to be HLA-B27 positive, the rheumatologist will be able to "split" these patients into those with AS and those without. Early diagnosis of AS in AAU patients is important as an early start of drug therapy and physiotherapy may prevent deformities and improve final rheumatologic outcome.

Back Pain↗
PubMed1986

IgG and IgA immune response against klebsiella in HLA-B27-associated anterior uveitis.

Enteric infections with Gram-negative bacteria are thought to play an important part in HLA-B27-associated disease such as Reiter's syndrome and reactive arthritis. But the role of bacterial infections in HLA-B27-positive ankylosing spondylitis (AS) and acute anterior uveitis (AU) is still controversial. A special interest has recently been devoted to the role of klebsiella infection in HLA-B27-associated disease. We studied the humoral immune response against a 'cross-reactive' strain of Klebsiella pneumoniae in 62 patients with anterior uveitis and 33 healthy controls. The anterior uveitis patients were subdivided into 25 HLA-B27-negative patients without AS (B27- AU+ AS-), 17 HLA-B27-positive patients without ankylosing spondylitis (B27+ AU+ AS-), and 19 HLA-B27-positive patients with ankylosing spondylitis (B27+ AU+ AS+). Total serum IgA was higher in patients than in controls in both the B27+ AU+ AS+ and B27+ AU+ AS- patients but not in the B27- AU+ AS- group. No abnormalities were observed in the total serum IgG levels. The level of both the IgG and IgA klebsiella antibodies did not differ in the various patient groups tested as compared with the controls. Comparisons between the patient groups showed that the IgG anti-klebsiella response was higher in B27-positive patients patients without AS than in those with AS. These results suggest that stimulation of mucosal surfaces may play a role in HLA-B27-associated anterior uveitis. Whether klebsiella organisms are involved in this stimulation remains unclear.

Adult↗
PubMed1985

Expression of HLA-B27 antigens on mononuclear leucocytes in ankylosing spondylitis.

Differences in expression of HLA-B27 antigens on immune competent cells might play a role in the susceptibility to environmental factors which may be responsible for the initiation of ankylosing spondylitis (AS). Using a quantitative complement-mediated lymphocytotoxity assay we determined the expression of HLA-B27 antigens on the membranes of mononuclear cells obtained from 20 patients with AS, four patients with other seronegative arthropathies and eight healthy controls. The variation in expression of B27 between individuals was quite extensive, but there was no significant difference in the mean titration curves obtained for each of the three groups. These findings suggest that the expression of HLA-B27 antigens on the membrane of mononuclear leucocytes does not play a role in the pathogenesis of AS.

Antigens, Surface↗
PubMed1984

Association of Gm allotypes with the occurrence of ankylosing spondylitis in HLA-B27-positive anterior uveitis.

We studied immunoglobulin Gm and Km allotypes in 54 patients with HLA-B27-positive anterior uveitis and in 204 healthy controls. No differences were noted between the two groups. Dividing the patients with anterior uveitis into those with ankylosing spondylitis (No. = 22) and those without it (No. = 32), produced interesting results. The Gm 1, 3, 17; 23; 5, 13, 21 phenotype was significantly (P = .007) increased in those within the ankylosing spondylitis and anterior uveitis group. Of these 22 patients, ten (45.5%) carried the Gm 1, 3, 17; 23; 5, 13, 21 phenotype compared to two of 32 (6.3%) in those with anterior uveitis alone and 33 of 204 (16.2%) normal controls. There were no significant differences between patients and controls in the frequencies of the other phenotypes tested.

Female↗