Efficacy of infliximab on MRI-determined bone oedema in psoriatic arthritis.
BACKGROUND
Psoriatic arthritis (PsA) is commonly associated with bone pathology, including entheseal new bone formation and osteolysis. On MRI, areas of active clinical involvement are represented by bone oedema and synovitis.


OBJECTIVE
To assess the impact of infliximab on bone oedema in PsA as shown by MRI.


METHODS
18 patients with joint swelling, psoriasis and seronegativity for rheumatoid factor received four infusions of infliximab, 3 mg/kg, in combination with methotrexate. MRI of the affected hand (12 patients) or knee joints (6 patients) was performed before and after treatment. The primary outcome was the assessment of bone oedema and synovitis at 20 weeks as shown by MRI. Secondary outcomes included the American College of Rheumatology (ACR) response criteria, psoriasis skin scores (Psoriasis Area and Severity Index (PASI)) and a quality of life measure (Psoriatic Arthritis Quality of Life (PsAQoL)).


RESULTS
At baseline, bone oedema was seen in 50% of patients (seven hands and two knees) in 30% of scanned joints, and this improved or resolved in all cases in the hand joints (p = 0.018) and in one knee joint at 20 weeks. Synovitis was found to be reduced in 90% of cases on MRI. Likewise, a significant improvement in all clinical outcomes, including PASI (p = 0.003) and PsAQoL (p = 0.006) was seen at week 20. 65% (n = 11) of the patients achieved an ACR response, of whom 45% had ACR70 or above and 54% had ACR20 or ACR50.


CONCLUSIONS
Infliximab treatment is associated with dramatic improvements in MRI-determined bone oedema in PsA in the short term. It remains to be determined whether infliiximib treatment is the cause for prevention of new bone formation, bone fusion or osteolysis in PsA as shown by radiography.
Marzo-Ortega
Helena
H
Consultant Rheumatologist, Academic Unit of Musculoskeletal Disease, Chapel Allerton Hospital, Chapeltown Road, Leeds LS7 4SA, UK. medhmo@leeds.ac.uk.
McGonagle
Dennis
D
Rhodes
Laura A
LA
Tan
Ai Lyn
AL
Conaghan
Philip G
PG
O'Connor
Philip
P
Tanner
Steven F
SF
Fraser
Alexander
A
Veale
Douglas
D
Emery
Paul
P
D000328:Adult; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D018501:Antirheumatic Agents / Q000627:therapeutic use*; D015535:Arthritis, Psoriatic / Q000150:complications / Q000188:drug therapy*; D001847:Bone Diseases / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology; D004487:Edema / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology; D005260:Female; D006801:Humans; D000069285:Infliximab; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement / Q000379:methods; D011788:Quality of Life; D012720:Severity of Illness Index; D016896:Treatment Outcome
D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents; D000069285:Infliximab