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H J Dinant

Publications and source records attributed to H J Dinant.

31 records · Page 2Linked to original sources

Lack of serologically defined arthritogenic Shigella flexneri cell envelope antigens in post-dysenteric arthritis.

Post-dysenteric or reactive arthritis (ReA) is closely associated with HLA-B27. This histocompatibility antigen is heterogeneous and consists of 2 serologically defined variants: B27M1+M2+ and B27M1+M2-. This paper gives a qualitative evaluation of the antibodies present in the sera of 62 patients with dysentery due to Shigella flexneri 2a, a known arthritogenic bacterium. The patients were classified in 4 groups: B27M1+M2+ReA+ (n = 5), B27M1+M2+ReA- (n = 7); B27M1+M2-ReA- (n = 1); B27-ReA- (n = 49). The isolated infectant possessed cell envelope antigens with B27M2-like epitopes (Mr 20,000). Analysis of the spectrum of antibodies directed against the separated cell envelope antigens of S. flexneri in the sera of these patients revealed 7 main patterns of reactivity. The detectable immunogens encompassed protein stainable antigens (Mr 98, 78, 68, 54, 50, 44, 41, 35, 14 and 13 kDa), lipopolysaccharides and peptidoglycan. None of the sera possessed detectable antibodies to the B27M2-like antigen. Consequently, this antigen is unlikely to be associated with ReA, and this applies equally to other antigens or patterns of antigens. The arthritogenicity of S. flexneri may therefore not be determined by the presence or absence of detectable antibody titers to certain cell envelope antigens. We hypothesize that other properties of these antigens could be of significance.

Antibodies, Bacterial↗

HLA-B27M1M2 and high immune responsiveness to Shigella flexneri in post-dysenteric arthritis.

The heterogeneous HLA-B27 antigen is closely associated with post-infectious or reactive arthritis (ReA) and is comprised of two serologically defined variants: B27M1+M2+ and B27M1+M2-. An outbreak of dysentery (n = 120) caused by a Shigella flexneri 2a strain, which possessed cell envelope antigens with epitopes resembling B27M2, resulted in five B27M1+M2+ patients with ReA. The remaining seven B27M1+M2+, one B27M1+M2- and all but three B27-negative patients remained free of joint symptoms; the latter three displayed arthralgia. IgM, IgG and IgA serum titers were statistically raised in all patient groups, but were exceptionally and persistently high in the B27M1+M2+ patients with ReA, especially IgA, as determined in acute-phase sera and sera sampled 1 year after dysentery. B27M1+M2+ thus appears to be a marker for a subset of disease, characterized by a high immune response. It is concluded that the B27M2 epitope is not unequivocally disease-related to Shigella ReA, that B27M1+M2+ is not likely to be the only immune-response-regulating gene involved in this form of ReA and that cross-reactivity between bacterial antigenic epitopes and B27 can only be part of a multifactorial process leading to ReA and in itself not sufficient to produce ReA. The intensity of the immune response appears to be another important factor.

Adolescent↗

Susceptibility and HLA-B27 in post-dysenteric arthropathies.

A recent outbreak of bacillary dysentery in The Netherlands revealed that, despite the close association of HLA-B27 with post-dysenteric or reactive arthritis (ReA), not even in one family did all HLA-B27 positive patients infected by an arthritogenic bacterium, develop ReA. This dissociation shows that additional factors beside B27 may determine susceptibility to ReA.

Adolescent↗

Alternative modes of cyclophosphamide and azathioprine therapy in lupus nephritis.

Forty-one patients with systemic lupus erythematosus and glomerulonephritis were studied in a randomized drug trial. Thirteen patients received prednisone only (Group 1), 16 received oral cyclophosphamide and oral azathioprine (1 mg/kg body weight . d of each initially) (Group 2), and 12 were given boluses of intravenous cyclophosphamide (0.5 to 1.0 g/m2 body surface area every 3 months) (Group 3). The mean observation period was 42 months (range 1 to 6.5 years). Renal function deteriorated in four of 12 patients in Group 1 and three of 27 patients in Groups 2 and 3 (p = 0.114). By life-table analysis, 86% of the entire group survived 5 years after entry to the study. Marked hypertension, fluctuating changes in serum creatinine, erratic changes in levels of antibody to DNA, reduced C3 levels, increasing proteinuria or sustained hematuria, and flares of extrarenal disease activity occurred more commonly in Group 1. Infectious complications were not commoner in Groups 2 and 3. We conclude that any marginal benefits produced by the programs tested cannot be shown in this class of patients without markedly increasing the sample size. Our current studies involve more vigorous treatment of patients with more acute disease and less treatment during prolonged periods of relatively good health.

Administration, Oral↗

Erythropoiesis and mean red-cell lifespan in normal subjects and in patients with the anaemia of active rheumatoid arthritis.

Recently developed ferrokinetic methods offer a tool to measure effective and ineffective erythropoiesis and mean red-cell lifespan (Ricketts et al, 1975). We have used this tool to investigate erythropoiesis in normal subjects and in patients with the anaemia of active rheumatoid arthritis. In normal subjects the results are comparable with the results published by Cavill et al (1977). In patients with the anemia of active rheumatoid arthritis there appears to be a total and an effective red-cell production as in the normal subjects. The ineffective erythropoiesis in the patients is increased and the produced red cells have a shortened mean lifespan in the circulation. The increased ineffective erythropoiesis is probably due to inadequate supply of iron to the marrow and the shortened mean red-cell lifespan to an extra-corpuscular haemolytic factor. The impaired marrow response to the anaemia of active rheumatoid arthritis has been confirmed.

Adult↗

Disability and health-related quality of life among patients with rheumatoid arthritis: association with radiographic joint damage, disease activity, pain, and depressive symptoms.

OBJECTIVE: To study the associations between disability and health-related quality of life (HRQoL), respectively, and radiographic joint damage, disease activity, pain, and depressive symptoms among patients with rheumatoid arthritis (RA). METHODS: Data were collected through questionnaires and clinical examinations at baseline (1997) and at 2 years' follow-up among patients with RA (n = 307). Disability was measured with a validated Dutch questionnaire, derived from the Health Assessment Questionnaire (HAQ), and HRQoL with a validated Dutch version of the RAND-36, using physical (PCS) and mental (MCS) component summary scales. Multivariate linear regression analyses were performed to assess the relationship between disability or HRQoL and radiographic damage, disease activity, pain, and depressive symptoms. RESULTS: Pain, with respect to disability and PCS, and depressive symptoms, with respect to MCS, were more important predictors than radiographic damage and disease activity. CONCLUSIONS: Daily RA practice needs to be broadened by regular assessment of disease burden from the patients' perspectives. Patient-reported measures, such as disability or HRQoL, should be incorporated for monitoring health outcomes of individual patients and for initiating and evaluating therapy.

Adult↗