Outcome of Early Monoarthritis: A Followup Study

AYMERIC BINARD, SEYDOU ALASSANE, VALÉRIE DEVAUCHELLE-PENSEC, JEAN M. BERTHELOT, SANDRINE JOUSSE-JOULIN, GERARD CHALÉS, CATHERINE LE HENAFF, JEAN B. THOREL, SYLVIE HOANG, PIERRE YOUINOU, and ALAIN SARAUX

ABSTRACT.

Objective. To evaluate clinical, laboratory, and radiological features and outcomes in patients with monoarthritis (MA), identified in a cohort of patients with early arthritis.

Methods. A cohort of 270 patients with undiagnosed arthritis of less than 1 year's duration was divided into 3 groups: single episode of MA (MA, n = 27), MA with a history of patient-reported arthritis (MA + past, n = 23), and oligo- or polyarthritis (OA/PA, n = 220). At 6-month intervals, all patients underwent a standardized examination, radiographs, and standard laboratory tests including rheumatoid factors (RF), antiperinuclear factor (APF), antikeratin antibody (AKA), anticyclic citrullinated peptide antibody (anti-CCP), antinuclear antibodies, and HLA-AB-DR typing. After a median followup of 30 months, the diagnosis was evaluated by a hospital-based rheumatologist.

Results. Age and sex did not differ across the 3 groups. Knee involvement was more common in the MA group than in the MA + past group (p < 0.03), whereas hand and metatarsophalangeal involvement was less common (p < 0.03 and p < 0.0001, respectively). RF and anti-CCP were less often positive in the MA group than in the MA + past group (p < 0.02 and p < 0.001, respectively) and the OA/PA group (p < 0.02 and p < 0.03). No patient in the MA group received a diagnosis of rheumatoid arthritis (RA). RA was less common and disease modifying antirheumatic drugs were prescribed less often in the MA group than in the other 2 groups (p < 0.0001 for both comparisons).

Conclusion. The MA group was clearly different from the other groups, with a favorable outcome and no risk of progression to RA. (First Release Nov 1 2007; J Rheumatol 2007; 34:2351-7)

Key Indexing Terms:

MONOARTHRITIS
EARLY SYNOVITIS
RHEUMATOID ARTHRITIS
UNDIFFERENTIATED ARTHRITIS

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From the Unit of Rheumatology and the Laboratory of Immunology, la Cavale Blanche Hospital, Brest Teaching Hospitals, Brest; Department of Rheumatology, Hôtel-Dieu Hospital, Nantes Teaching Hospitals, Nantes; Department of Rheumatology, Rennes Teaching Hospitals, Rennes; Department of Rheumatology, Morlaix Hospital, Morlaix; Department of Rheumatology, Lorient Hospital, Lorient; and Department of Rheumatology, Vannes Hospital, Vannes, France.

A. Binard, MD; S. Alassane, MD; V. Devauchelle-Pensec, MD; S. Jousse-Joulin MD; P. Youinou, MD, PhD; A. Saraux, MD, PhD, Unit of Rheumatology and Laboratory of Immunology, la Cavale Blanche Hospital, Brest Teaching Hospitals; J.M. Berthelot, MD, Department of Rheumatology, Hôtel-Dieu Hospital, Nantes Teaching Hospitals; G. Chalés, MD, PhD, Department of Rheumatology, Rennes Teaching Hospitals; C. Le Henaff, MD, Department of Rheumatology, Morlaix Hospital; J.B. Thorel, MD, Department of Rheumatology, Lorient Hospital; S. Hoang, MD, Department of Rheumatology, Vannes Hospital.

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

Accepted for publication December 29, 2006.

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