[1] Canterbury Christ Church Univ, Canterbury, England
[2] Natl Res Ctr, Internal Med, Rheumatol & Rehabil, Cairo, Egypt
[3] Cairo Univ, Internal Med, Cairo, Egypt
[4] Justus Liebig Univ Giessen, Dept Rheumatol & Clin Immunol, Campus Kerckhoff, Bad Nauheim, Germany
[5] Univ Aquila, Ist Clin Med, Laquila, Italy
[6] Univ Aquila, Dept Biotechnol & Appl Clin Sci, Unit Rheumatol, Laquila, Italy
[7] Kerckhoff Klin GmbH, Abt Rheumatol & Klin Immunol, Benekestr 2-8, D-61231 Bad Nauheim, Germany
[8] Assiut Univ, Rheumatol & Rehabil, Assiut, Egypt
[9] Ain Shams Univ, Community & Publ Hlth, Cairo, Egypt
[10] Fayoum Univ, Rheumatol & Rehabil, Al Fayyum, Egypt
[11] Ain Shams Univ, Rheumatol & Rehabil, Cairo, Egypt
[12] Tanta Univ, Rheumatol & Rehabil, Tanta, Egypt