Images of the month: Lower-back pain in a young man with HLA B27 - not always spondyloarthritis!

Presence of human leucocyte antigen (HLA) B27 in a patient with lower-back pain should not be considered synonymous with axial spondyloarthritis. Other causes of back pain should be ruled-out by careful evaluation. Lumbosacral transitional vertebra is a common congenital malformation of spine which frequently leads to mechanical back pain. We present a young man with lower-back pain who had HLA B27. He was labelled with axial spondyloarthritis elsewhere and was given etanercept without benefit. Further evaluation revealed that he had lumbosacral transitional vertebra and spina bifida occulta. No evidence of sacroiliitis was found. Etanercept was stopped and he was started on physiotherapy protocol for transitional vertebra, with which he improved remarkably. This case highlights the need for greater awareness among clinicians about lumbosacral transitional vertebra, a finding which is frequently missed. Presence of HLA B27 can be coincidental, as in our case.

The impact of obesity on inflammatory markers used in the assessment of disease activity in rheumatoid arthritis - a cross-sectional study.

INTRODUCTION: Obesity is known to be associated with elevated levels of inflammatory markers. The aim of the study was to assess the confounding effect of obesity on the levels of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) in patients with rheumatoid arthritis (RA) in low disease activity state or remission as indicated by clinical disease activity index (CDAI). MATERIAL AND METHODS: Adult RA patients with CDAI less than 10 were divided into two groups: obese and non-obese, based on body mass index. Relevant exclusions were applied to eliminate causes of raised inflammatory markers other than obesity. The difference of CRP and ESR levels between the obese and non-obese groups was analyzed. RESULTS: Obese patients with RA (n = 85) had higher CRP and ESR than non-obese patients (n = 66) (p-values 0.008 and 0.000005, respectively). In addition, obese females with RA had significantly higher CRP and ESR as compared to non-obese females. However, the difference was not significant in males. Twenty-one obese (24.7%) and two non-obese RA patients (3%) had elevated CRP (difference of approximately 22% [24.7 minus 3]). Forty obese (47%) and 16 non-obese RA patients (24.2%) had elevated ESR (difference of approximately 23% [47 minus 24.2]). Thus, obesity was the attributable cause of falsely elevated CRP and ESR in 22% and 23% of patients, respectively. CONCLUSIONS: About one-fifth of patients with RA, who are actually in low disease activity, may have elevated inflammatory markers, primarily because of obesity. Therefore, elevated CRP and ESR in obese patients with RA should be interpreted with caution because it may lead to unnecessary overtreatment.