Comparison of anti cyclic citrullinated protein 2 serum levels with rheumatoid factor for the diagnosis of rheumatoid arthritis in Gaza Strip

Other Title(s)

مقارنة مستوى الأجسام المضادة ضد بروتين السيترولين 2 مع عامل الروماتزم في تشخصي التهاب المفاصل الروماتزمي في قطاع غزة

Dissertant

Skaik, Bushra M.

Thesis advisor

Shubayr, Muhammad E.

University

Islamic University

Faculty

Faculty of Science

Department

Department of Biological Science

University Country

Palestine (Gaza Strip)

Degree

Master

Degree Date

2008

English Abstract

Background : Rheumatoid Arthritis (RA) is the most common autoimmune disease.

However, specific and practicable tests for its specific diagnosis are lacking.

Therefore, a good marker should ideally not only indicate the development of the disease, but also be able to differentiate RA from other similar diseases and to help early diagnosis.

The new marker which has been tested in this study is the anti citrullinated protein antibody "ACCP2A".

Objective : to compare the diagnostic value and clinical utility of (ACCP2A) with IgM rheumatoid factor (IgM RF) in patients with RA in Gaza Strip.

Methods : in cross sectional study ; ACCP2A and IgM RF were determined in 142 serum samples; 67 patients suffering from arthritis, and 75 healthy controls.

All patients were diagnosed according to the guidelines of American College of Rheumatology (ACR) and by rheumatologist.

Both tests were assessed by enzyme linked immunosorbent assay (ELISA).

C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were also assayed as inflammatory parameters for all subjects.

All clinical features (onset for RA, early symptoms, classification criteria, extra-articular disease, and radiographic manifestations) and medications were investigated by questionnaire interviews.

And all results were analyzed by SPSS version "15".

Results : at a cutoff value of (> 5 U / ml) for ACCP2A ; sensitivity was 56 % and specificity was 99 % and at a cutoff value of (> 6 IU / ml) for IgM RF; it had a higher sensitivity (85 %) and a lower specificity (69 %) than ACCP2A.

The area under the receiver operating characteristics (ROC) curve (AUC) for ACCP2A was 0.80 (95% confidence interval, 0.70 – 0.90) and for IgM RF was 0.83 (95 % confidence interval, 0.74 – 0.92).

In addition, there were significant differences in the mean levels of ACCP2A (34.5 v 1.4) and IgM RF (98 v 20) between RA patients and healthy plus other patient groups.

Although the concordance between both tests was significant (p = 0.000), IgM RF as the single positive marker was found in 35 % and ACCP2A as a single marker in 6 %.

However, when the two markers were tested simultaneously, sensitivity and specificity reached 88 % and 100 %.

There was no significant correlation between ACCP2A and personal characters such as age, gender, family history and smoking.

IgM RF didn’t show significant correlation with these characters except with gender.

A correlation with extra-articular manifestations, severity of erosions and CRP was observed for both tests.

ACCP2A didn't show significant correlation with ESR but IgM RF showed a significant correlation with it.

Conclusion : ACCP2A was more specific than IgM RF in diagnosis of RA.

So it could be a useful serological assay in establishing the diagnosis of RA especially in ambiguous cases or RF negative patients with RA.

However, a combination of both assays acts as "gold standard" in diagnosis of RA patients in Gaza Strip.

And both assays are also a better predictor of disease severity.

Main Subjects

Medicine

Topics

• Palestine
• Gaza Strip
• Diagnosis

No. of Pages

102

Table of Contents

• APA
• MLA
• AMA

Language

English

Data Type

Arab Theses

Record ID

BIM-303426