Whole-body MRI of patients with polymyalgia rheumatica identifies a distinct subset with complete patient-reported response to glucocorticoids.

Abstract

OBJECTIVES:

To determine whether whole-body MRI defines clinically relevant subgroups within polymyalgia rheumatica (PMR) including glucocorticoid responsiveness.

METHODS:

22 patients with PMR and 16 with rheumatoid arthritis (RA), untreated and diagnosed by consultant rheumatologists, underwent whole-body, multiple-joint MRI, scored by two experts. Patients with PMR reported whether they felt 'back to normal' on glucocorticoid therapy and were followed for a median of 2 years.

RESULTS:

All patients with PMR were deemed to respond to glucocorticoids clinically. A characteristic pattern of symmetrical, extracapsular inflammation, adjacent to greater trochanter, acetabulum, ischial tuberosity and/or symphysis pubis, was observed in 14/22 of the PMR cases. In PMR, this pattern was associated with complete glucocorticoid response (p=0.01), higher pretreatment C-reactive protein (CRP) and serum interleukin-6 (IL-6), and better post-treatment fatigue and function. Only 1/14 in the extracapsular group could stop glucocorticoids within 1 year, compared with 4/7 of the others. A score derived from the five sites discriminating best between PMR and RA correlated with IL-6 (p<0.002). IL-6 levels ≥16.8 pg/mL had 86% sensitivity and 86% specificity for the extracapsular MRI pattern.

CONCLUSIONS:

A subset of patients with rheumatologist-diagnosed PMR had a characteristic, extracapsular pattern of MRI inflammation, associated with elevated IL-6/CRP and with complete patient-reported glucocorticoid responsiveness.

• Authors: Sarah Louise Mackie, Colin Thomas Pease, Eiji Fukuba, Emma Harris, Paul Emery, Richard Hodgson, Jane Freeston, Dennis McGonagle
• Journal: Annals of the rheumatic diseases (Ann Rheum Dis) Vol. 74 Issue 12 Pg. 2188-92 (Dec 2015) ISSN: 1468-2060 [Electronic] England
• PMID: 26376658 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Chemical References

• Glucocorticoids
• Prednisolone

Topics

• Aged
• Aged, 80 and over
• Disease Progression
• Dose-Response Relationship, Drug
• Female
• Follow-Up Studies
• Glucocorticoids (therapeutic use)
• Humans
• Magnetic Resonance Imaging
• Male
• Middle Aged
• Polymyalgia Rheumatica (diagnosis, drug therapy)
• Prednisolone (therapeutic use)
• Treatment Outcome
• Whole Body Imaging (methods)