High resolution ultrasound (HRUS) was used to investigate the effects of tumour necrosis factor alpha (TNFalpha) blockade on pannus formation and vascularisation of small finger joints in patients with active rheumatoid arthritis (RA).
Five patients with active RA were treated with etanercept, a soluble TNFalpha receptor protein, for one month. Before, during, and after treatment the patients were followed up by clinical rheumatological examination, determination of their subjective pain score, blood chemistry, and by HRUS of the second metacarpophalangeal (MCP) joint of the right hand.
One month after treatment with etanercept, rheumatological examination showed a significant decrease in a modified single joint rheumatic disease activity index (from 2.9 (SD 0.2) to 1.2 (0.7); p<0.05) in all patients. Moreover, a significant decrease in the general pain score (from 4.7 (0.4) to 1.8 (0.6); p<0.05) and in C reactive protein (CRP) levels was seen (from 3.02 (0.9) to 0.24 (0.1); p<0.05). Concordantly, HRUS showed a significant reduction in pannus vascularisation of the MCPII joints (from 23,602 (5339) to 2907 (1609) colour signals/region of interest, CS/ROI; p<0.001). Pearson's correlation coefficient between the results obtained by HRUS and the clinical response was 0.85.
HRUS is promising as an additional useful method in the assessment of RA activity, and probably also in monitoring therapeutic responses.