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T E Feltkamp

Publications and source records attributed to T E Feltkamp.

At least 55 records · Page 3Linked to original sources
PubMed1990

Serum levels of beta 2-microglobulin in HLA-B27+ patients with acute anterior uveitis and ankylosing spondylitis.

Serum levels of beta 2m were monitored in 89 HLA-B27+ patients with acute anterior uveitis (AAU) and in their first degree relatives. Serum levels of both patients and relatives were not elevated compared to sex and age matched controls. Neither the activity of the uveitis, nor the presence or absence of ankylosing spondylitis (AS), correlated with beta 2m levels. On the contrary, 6 of 27 HLA-B27- patients with AAU had elevated serum levels of beta 2m. These findings do not confirm previous reports which showed elevated serum levels of beta 2m in patients with AS. A possible role for beta 2m in the pathogenesis of HLA-B27+ AAU and AS is discussed.

Acute Disease↗
PubMed1989

HLA-B27+ acute anterior uveitis and other antigens of the major histocompatibility complex.

Acute anterior uveitis (AAU) is associated with HLA-B27 in 50% of the patients. Although the association between HLA-B27 and AAU is evident, other genetic factors probably also play a pathogenic role. To investigate whether HLA-B27 only serves as a marker gene for genes next to the B-locus, class I and II HLA antigens of 62 HLA-B27+ AAU patients were determined. Increased frequencies were found for HLA-Cw1, Cw2, DR4, DRw12 and DQw3 if the AAU patients were compared with normal controls. However, when the data were compared to a group of HLA-B27+ controls, no differences were observed. The supposed associations were therefore probably due to linkage disequilibrium with HLA-B27. Homozygosity for HLA-B27 seemed not to increase the chance to acquire AAU. HLA-DR4 was present less frequently in AAU patients with ankylosing spondylitis than in AAU patients without this disease. Haplotype analysis of 21 families revealed that not all relatives suffering from AAU shared the HLA-B27+ haplotype with the proband. Of seven relatives suffering from AAU, five carried the same HLA-B27+ haplotype as the proband, one had inherited another HLA-B27+ haplotype and the last one was HLA-B27-. In conclusion, we could not bring forward any reason to suggest that genes on the short arm of chromosome 6--other than HLA-B27--play a role in the pathogenesis of HLA-B27+ AAU.

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

Perivascular infiltration in normal skin of patients with rheumatoid arthritis: association with rheumatoid factors and HLA-DR antigens.

The relation between immunohistological findings in biopsy specimens of apparently normal skin, HLA antigens, and rheumatoid factors (RF) was studied in 120 patients with rheumatoid arthritis (RA), selected for treatment with D-penicillamine. Perivascular infiltration (PVI) of more than three mononuclear cells was present in 77 (68%) of 114 patients, accompanied usually by the presence of IgM or C3, or both, in immunofluorescence studies. The number of perivascular cells was associated significantly with the titre of circulating RF. A weak relation of both perivascular cellular infiltration and RF with HLA-DR3 and DR4 did not reach statistical significance. It is concluded that the histological presence of perivascular inflammation is associated mainly with deposition of RF. It is suggested that the first is merely an epiphenomenon of the latter. PVI was not prognostic for the occurrence of the clinical syndrome of rheumatoid vasculitis. For practical purposes skin biopsies do not appear to be useful in the evaluation of individual patients with RA.

Adult↗
PubMed1988

Standardisation of the quantitative determination of antinuclear antibodies (ANAs) with a homogeneous pattern.

The results of antinuclear antibody tests using the indirect immunofluorescence technique may be reported as a description of the pattern and the intensity of fluorescence obtained at a certain dilution. If quantitative results are required titration is necessary. Such titrations may vary greatly between different laboratories. The present study involving 26 laboratories shows an improvement of interlaboratory comparability for the homogeneous fluorescence pattern when a common reference serum is used. Cultured cells as substrate appear to give better quantitative agreement than rat liver sections. National reference sera should be standardised in items of the appropriate WHO reference preparation.

Antibodies, Antinuclear↗
PubMed1988

The first international standard for antibodies to double stranded DNA.

This paper announces the availability of the first international standard for anti-double-stranded DNA (anti-dsDNA). The material, coded Wo/80, was obtained after recalcification of plasma taken from a patient with systemic lupus erythematosus. Vials were filled with 500 microliters serum and freeze dried. The serum contains no other autoantibodies in measurable quantities. The vials should be stored at -20 degrees C. The standard should be used for establishing national, regional, or local standards. In eight laboratories satisfactory results with the immunofluorescence technique on Crithidia luciliae were obtained; the titres varied between 1/20 and 1/640 (mean 1/160). In seven laboratories the Farr assay, with the so called 'Amersham kit', was performed. At a dilution of 1:40 a mean binding percentage of about 50% was observed. After reconstitution with 500 microliters of distilled water, the vial contains 100 IU/500 microliters or 200 IU/ml. The standard can be obtained from the custodian of WHO: Central Laboratory of the Netherlands Red Cross Blood Transfusion Service, PO Box 9190 1006 AD Amsterdam, The Netherlands.

Antibodies, Antinuclear↗
PubMed1988

Expression of rheumatoid factors in titres or units?

About 1% of the Dutch population is per year checked for the first time for the presence of rheumatoid factors (RF). Unfortunately, the interlaboratory variations of the titres of RF tests are enormous. We therefore (re)studied the effect of comparisons of the results with the WHO standard rheumatoid serum, leading to expression of the results in international units (IU), instead of in titres. Testing 5 sera in duplicate in 33 laboratories, a significant decrease of the interlaboratory variability was noted for the Waaler-Rose test, the Latex fixation test and the ELISA for the demonstration of RF's. Also the results of the antiperinuclear factor (APF) test improved significantly. The results of RF's demonstrated with the indirect immunofluorescence technique showed already a satisfactory comparability. Expression in IU's had no significant effect for this test. The introduction of the use of a reference serum met no opposition. Nearly all Dutch laboratories express now their results in units.

Agglutination Tests↗
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↗
PubMed1986

HLA-antigens in the human uvea.

With the use of monoclonal antibodies in an indirect immunofluorescence technique we studied the distribution of Class I (HLA-ABC and B27) and Class II (HLA-DR) antigens in the human uvea. W6/32, directed against the core of HLA-ABC antigens, was used to study the distribution of Class I antigens. The anterior border layer of the iris, the non-pigmented and pigmented epithelium and the external basement membrane of the ciliary body and the vascular endothelium in the uvea showed a positive staining for Class I antigens. B27/M1, directed against an epitope of the HLA-B27 antigen, and the control antibody A11/Aw24, which was directed against an epitope of HLA-A11, revealed the same distribution pattern in respectively HLA-B27 and HLA-A11 positive donor eyes. The intensity of their staining was much weaker than the staining with W6/32. Class II antigens were studied with OkIa1, an antibody directed against the core of HLA-DR antigens. HLA-DR antigens were detectable on single cells scattered throughout the entire uvea. These cells did not seem to relate to any anatomical entity. No staining for Class II antigens was seen in the uveal blood vessel endothelium. The expression of HLA-antigens in the uvea is compatible with the distribution in other tissues. These findings suggest that the expression of HLA-B27 in the human uvea does not explain why the eye is one of the target tissues in HLA-B27 associated disease.

Adolescent↗
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↗
PubMed1984

Azathioprine in the treatment of systemic lupus erythematosus. A three-year prospective study.

In a prospective study, the effect of azathioprine on the clinical course and the anti-dsDNA profile was evaluated in 17 patients with systemic lupus erythematosus (SLE). During this prospective longitudinal study, exacerbations were never observed. Three periods of continuous anti-dsDNA increases with a doubling time (T2) shorter than 10 weeks were noted. Both the clinical symptoms and the anti-dsDNA levels improved after the administration of azathioprine. These results necessitate a careful double-blind trial for the use of this drug to prevent SLE exacerbations.

Adult↗
PubMed1984

Lymphoid proliferations in the orbit: malignant or benign?

Clinical, pathological, and immunological analysis of 20 patients with ocular adnexal lymphoid disease has demonstrated several parameters which are useful for distinguishing malignant from benign lesions. Patients in the fourth or fifth decade of life presenting with an acute history of pain, oedema, epiphora, double vision, and ptosis, with a mass localised in the lacrimal gland area, are more likely to have a pseudolymphoma or a chronic inflammatory lesion than a true non-Hodgkin lymphoma (NHL). It is not possible to obtain a definite diagnosis without surgical intervention, because only three out of nine patients with orbital NHL had evidence of a monoclonal B cell population in peripheral blood on admission to the Orbital Centre. Furthermore it was confirmed that the identification of the various orbital lymphoid infiltrates becomes more distinct when immunological techniques are added to the clinical and histopathological methods of investigation. Multidisciplinary cooperation leads to further improvement of diagnosis and treatment of ocular adnexal lymphoproliferative disease.

Adult↗