Statistics from Altmetric.com
A 64 year old male bus driver presented to the rheumatology clinic with a six month history of bilateral painful swollen knees. On further questioning, he admitted to hand arthralgia when gripping tightly but no other locomotor complaint. He had a history of orchidectomy for benign disease and controlled hypertension. His general practitioner reported normal serum urate levels, raised erythrocyte sedimentation rate (ESR), and radiological evidence of mild osteoarthritis in the right knee. The main findings on musculoskeletal examination were large bilateral knee effusions with reduced range of movement. Subsequent investigations confirmed a raised ESR (75 mm/1st h) and C reactive protein (73 mg/l), diffuse increase in immunoglobulin fractions but negative myeloma screen in blood and urine, absence of crystals in synovial fluid, and no evidence of an inflammatory arthropathy on hands and feet radiographs. He responded very well to intra-articular triamcinolone and physiotherapy.
Autoantibody analysis reported a positive Rose-Waaler rheumatoid factor (RF) test of high titre 1/16384, positive antinuclear antibodies 1/640, homogeneous pattern, with negative double stranded DNA antibodies (Crithidia method), and negative extractable nuclear antigen antibodies. Over the ensuing months, he developed features of an inflammatory arthropathy affecting his hands and ankles and recurring at his knees, with a further rise in inflammtory markers. Treatment with sulfasalazine was instituted with good clinical response, although his ESR and CRP both remained close to 100. A repeat RF, six months after presentation and three months after starting sulfasalazine, recorded a positive result, titre 1/16 777 216 (yes—over 16 million!), with no substantive change in other autoantibodies. Over the ensuing 12 months, his arthritis was symptomatically well controlled with sulfasalazine and he continued working, but his inflammatory markers remained very high. His RF titre fell to a mere 1/1 048 576 within one month, 1/524 288 within four months, and most recently measured 1/2048, again with little change in other autoantibodies or clinical course.
In what is, perhaps, a slightly atypical presentation of rheumatoid arthritis, has anyone got an explanation for this patient’s RF titre and can a world record be claimed—if only to recognise the persistence and determination of the laboratory technician?
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.