We have developed a solid-phase radioimmunoassay capable of detecting nanogram quantities of human IgA rheumatoid factor (RF) in biological fluids. Human IgM RF, IgG RF, IgG, IgA, IgM and whole serum did not significantly interfere with the IgA RF assay. Patients with sero-positive rheumatoid arthritis (RA) had significantly higher concentrations of IgA RF than sero-negative RA patients or healthy adult controls. Concentrations of IgA RF in paired sera and synovial fluids from sero-positive RA patients were comparable. Levels of IgA RF demonstrated a moderately good correlation with levels of IgM RF in sero-positive RA sera (r = 0.673). However, the ratio of IgA RF concentration to IgM RF concentration in sero-positive RA sera varied widely.

Thesis (M.P.H.)--University of Hong Kong, 2006.

Thesis (M. P. H.)--University of Hong Kong, 2006. / Also available in print.

A patient had spurious thrombocytopenia resulting from a mechanism not previously described. Whereas in prior reports the in vitro phenomenon of platelet clumping has been effected by either EDTA‐dependent or temperature‐dependent antibodies capable of direct platelet agglutination, neither the IgG nor the IgM fractions of this patient's serum demonstrated such activity. However, agglutination was produced by incubating allogeneic platelets with the IgG fraction followed by a room temperature incubation with the rheumatoid factor‐positive IgM fraction. The data support a new mechanism for spurious thrombocytopenia resulting from the interaction of a cold‐reactive rheumatoid factor with antiplatelet antibody.

published_or_final_version / Community Medicine / Master / Master of Public Health

No description available.

Disease progression in rheumatoid arthritis (RA) is assessed by standard clinical, radiological and functional measures. Clinical disease activity in RA is graded as no disease (remission), low, moderate and high disease, based on validated criteria. Radiological progression in RA is monitored by serial x-rays of hands and feet, and by quantification of structural damage, using various scoring methods. This proves to be a valuable outcome measure in RA studies. RA patients with active disease usually develop progressive radiological damage. However, it has been shown that clinical disease activity may not correlate with radiological damage, particularly in early RA. Therefore, this thesis was mainly aimed to test the hypothesis that, „radiological damage can progress despite clinical disease inactivity or remission‟ and to investigate possible underlying mechanisms including disease heterogeneity, treatment effect and scoring methodology. Disease progression, outcomes and prognostic factors were analysed in an inception cohort of early RA (Early Rheumatoid Arthritis Study/ERAS) for this thesis. In this study of early RA patients, sustained remission was less frequent than remission at individual time points and baseline variables such as gender, duration of symptoms, disease activity (DAS) and health assessment questionnaire (HAQ) scores have shown predictive value for sustained remission. Structural damage on x-rays progressed despite clinical disease inactivity or remission in a subgroup of patients and disease heterogeneity was the most likely explanation for the disconnect between clinical disease activity and radiological damage in the ERAS cohort. This study has also found that scoring methods as well as reading order of x-ray films could influence radiographic progression in early RA, particularly at individual level. Male sex, rheumatoid factor (RF) and radiographic damage at baseline showed prognostic value in predicting radiographic progression despite remission. Study patients with persistent clinical disease inactivity have shown better radiological, surgical, functional, and other outcomes compared to relapsing-remitting or persistent disease activity. There was no significant difference in functional and other outcomes between patients in remission with x-ray progression and those in remission without xray progression. Therefore, x-rays of hands and feet at regular intervals are valuable in determining true disease progression in early RA, even during clinical disease inactivity. Scoring methodology in itself could have an influence on the type of radiographic progression in RA studies. Sustained disease inactivity in RA is more favourable than relapsingremitting disease.

京都大学 / 新制・課程博士 / 博士(医学) / 甲第24991号 / 医博第5025号 / 新制||医||1069(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 生田 宏一, 教授 椛島 健治, 教授 上野 英樹 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Thesis (Ph.D. in Biostatistics) -- University of Colorado Denver, 2008. / Typescript. Includes bibliographical references (leaves 53-56). Online version available via ProQuest Digital Dissertations.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A artrite reumatÃide à uma doenÃa auto-imune crÃnica e inflamatÃria que evolui com graus de destruiÃÃo articular e alteraÃÃes extra-articulares podendo levar a incapacidade funcional. AlÃm da avaliaÃÃo clÃnica o diagnÃstico baseia-se na determinaÃÃo do fator reumatÃide (FR) sendo que este à tambÃm positivo em indivÃduos saudÃveis como tambÃm em outras doenÃas auto-imunes e infecciosas. Os anticorpos antipeptÃdeos citrulinados cÃclicos (anti-CCP) tem sido usados no diagnÃstico da artrite reumatÃide sendo superiores ao fator reumatÃide (FR) no diagnÃstico da artrite reumatÃide (AR) recente. O estudo teve como objetivo demonstrar a presenÃa de anticorpos anticitrulina em pacientes com o diagnÃstico de artrite reumatÃide comparando com parÃmetros clÃnicos, laboratoriais e com a avaliaÃÃo da qualidade de vida desses pacientes. Para avaliar a qualidade de vida foi aplicado o questionÃrio âHealth Assessment Questionnaire.â Foi realizado um teste por imunoturbidimetria, para a detecÃÃo de FR (Roche, Indianopolis, EUA) e ELISA para o anti-CCP (Inova , San Diego, EUA) em 69 pacientes apresentando, ao menos, 4 dos critÃrios do ColÃgio Americano de Reumatologia para a classificaÃÃo de AR e em 20 controles saudÃveis. A anÃlise estatÃstica utilizou o teste exato de Fisher e teste de Spearmann com significÃncia alcanÃada com P<0.05. Os pacientes com AR tinham entre 18-75 (mÃdia = 43.9 anos), 66 (95.7%) eram mulheres, os controles com idades variando entre 20-60 anos. O inÃcio da AR variou de 4 a 384 meses (mÃdia = 74.0 e mediana = 48.0). FR foi positivo em 48 (69.6%) pacientes e 1 (0,5%) controle. O anti-CCP foi positivo em 36 (52.2%) pacientes e em 2 (10%) controles. Foi observada uma correlaÃÃo significante dos testes FR e anti-CCP com P< 0.0001 e este estudo sugere que o anti-CCP nÃo foi superior ao FR no diagnÃstico da AR estabelecida / Rheumatoid arthritis is an inflammatory, chronic and auto-immune disease that develops in degrees of articular destruction and extra-articular changes being able to lead to functional disability. Besides clinical assessment the diagnosis is based on the determination of the rheumatoid factor being this one also positive in healthy people as well as in other infectious and auto-immune diseases. Anticyclic citrullinated peptide (anti-CCP) antibodies have been used in diagnosis of rheumaoid arthritis (RA) and seen to be superior to rheumatoid factor (RF) in early onset RA diagnosis. The target of the study is to demonstrate the presence of anticitrulline antibodies in patients with rheumatoid arthritis diagnostic comparing with laboratory, clinical parameters and with the assessment of the quality of life of these patients. The âHealth Assessment Questionnaireâ has been used to assess the quality of life. We performed an immunoturbidimetry test for detection of RF (Roche,Indianopolis, USA) and an ELISA for anti-CCP antibodies (Inova, San Diego, USA) in 69 patients presenting, at least, 4 of the American College of Rheumatology criteria for classification of RA and in 20 healthy controls. For statistical analysis we used thr Fisher exact test and the Spearmann test Significance was reached wuth P<0.05. RA patients were aged between 18-75 years (mean = 43.9 years), 66 (95.7%) of then were female, controls age ranged between 20-60 years.The period of RA onset varied from 4 to 384 months (mean = 74.0 and median = 48.0). RF was positive in 48 (69.6%) patients and in 1 (0,5%) control. The anti-CCP was positive in 36 (52.2%) patients and in 2 (10%) controls. A significant correlation of RF and anti-CCP tests was observed with P< 0,0001 and this study suggests that anti-CCP was not superior to RF in diagnosis of established RA