Value of Antibodies to Citrulline-Containing Peptides for Diagnosing Early Rheumatoid Arthritis

ALAIN SARAUX, JEAN M. BERTHELOT, VALÉRIE DEVAUCHELLE, BOUTAHAR BENDAOUD, GÉRARD CHALÈS, CATHERINE LE HENAFF, JEAN B. THOREL, SYLVIE HOANG, SANDRINE JOUSSE, DOMINIQUE BARON, PAUL LE GOFF, and PIERRE YOUINOU

ABSTRACT.

Objective. To compare the diagnostic values of antiperinuclear factor (APF), antikeratin antibody (AKA), and anti-cyclic citrullinated peptides (anti-CCP) to discriminate between patients with and without rheumatoid arthritis (RA) and to determine the diagnostic value of anti-CCP used alone or with other tests.

Methods. Two hundred and seventy patients with early arthritis underwent standardized investigations in 1995–1997. The clinical utility of APF, AKA, and anti-CCP in first-visit sera was evaluated using receiver-operating characteristic curves. Combinations of anti-CCP with other laboratory tests were assessed by multiple logistic regression.

Results. Anti-CCP, APF, and AKA were not perfectly correlated with one another. Anti-CCP with 53 UI as the cutoff was 47% sensitive and 93% specific, versus 52% and 79%, and 47% and 94%, for APF and AKA, respectively. Multiple logistic regression selected anti-CCP, AKA, IgM-rheumatoid factor (RF) ELISA, and the latex test.

Conclusion. Rheumatologists can routinely use 2 or 3 tests for diagnosing RA (latex and/or IgM RF ELISA, and either AKA or anti-CCP ELISA) and can add a third or fourth test when the diagnosis remains in doubt. (J Rheumatol 2003;30:2535-9)

Key Indexing Terms:

RHEUMATOID ARTHRITIS
DIAGNOSIS
IMMUNOLOGY

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From the Unit of Rheumatology and the Laboratory of Immunology, Hôpital de la Cavale Blanche, CHU Brest; the Department of Rheumatology, Hôtel-Dieu, CHU Nantes; the Department of Rheumatology, CHU Rennes; the Department of Rheumatology, CHR, Morlaix; the Department of Rheumatology, CHR, Lorient; and the Department of Rheumatology, CHR, Vannes, France.

Supported in part by the Brest Hospital Center and the 1995 Clinical Research Hospital Program (PHRC 1995).

A. Saraux, MD, PhD; V. Devauchelle, MD; B. Bendaoud, PhD; Jean M Berthelot, MD; S. Jousse, MD; D. Baron, MD; P. Le Goff, MD; P. Youinou, MD, PhD, Unit of Rheumatology and the Laboratory of Immunology, Hôpital de la Cavale Blanche; G. Chalès, MD, Department of Rheumatology, CHU Rennes; C. Le Henaff, MD, Department of Rheumatology, CHR Morlaix; J.B. Thorel, MD, Department of Rheumatology, CHR Lorient; S. Hoang, MD, Department of Rheumatology, CHR Vannes.

Address reprint requests to Prof. A. Saraux, Rheumatology Unit, Hôpital de la Cavale Blanche, BP 824, F 29609 Brest-Cedex, France. E-mail: Alain.Saraux@chu-brest.fr

Submitted January 17, 2003; revision accepted May 22, 2003.

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