ATLANTA — Gadolinium-enhanced MRI improved diagnostic accuracy in patients with polymyalgia rheumatica and helped predict disease recurrence, according to a presenter here.
“Polymyalgia rheumatica, or PMR, is a glucocorticoid-responsive muscle pain and stiffness, especially in the shoulders and hips. PMR is clinically diagnosed based on the systems, but accurate diagnosis is difficult because the symptoms may occur in other rheumatologic and inflammatory conditions,” Kazuro Kamada, MD, a rheumatologist at Tomakomai City Hospital in Japan, said during a press conference.
Recent data demonstrated, however, the utility of ultrasonography to detect biceps tenosynovitis and subdeltoid bursitis, findings specific to polymyalgia rheumatica. MRI may visualize muscle and bone lesions, but its use in this disease has not been established.
Based on this need, Kamada and colleagues examined whether gadolinium-enhanced MRI might improve diagnostic accuracy and predict prognosis.
The study included 175 patients who presented to Tomakomai City Hospital between June 2012 and June 2018 with bilateral shoulder pain who fulfilled the Bird classification criteria for polymyalgia rheumatica. Of these, 137 underwent gadolinium-enhanced MRI and ultrasound exams and 58 patients received a diagnosis of polymyalgia rheumatica.
Those diagnosed received prednisone 20 mg per day, which was tapered after remission. Patients were followed until June 2019 to determine symptom recurrence.
MRI findings included enhancement of joint capsule, rotator cuff tendon or biceps tendon, synovial hypertrophy, shoulder joint effusion, enhancement of glenohumeral joint and/or focal or diffuse bone edema in humerus heads, according to Kamada and colleagues.
Patients with polymyalgia rheumatica had significantly more frequent enhancement of joint capsule (69% vs. 35%; P < .01) or rotator cuff tendon (72% vs. 32%; P < .01) and focal bone edema in humerus heads (59% vs. 19%; P < .01). Compared with ultrasound, using these three MRI findings together to diagnose polymyalgia rheumatic increased sensitivity (50% vs. 76%) and specificity (72% vs. 85%).
At follow-up, 24 patients experienced recurrence. All were of younger ages (P = .04), had less enhancement of rotator cuff tendon (58% vs. 87%; P = .02) and more synovial hypertrophy (21% vs. 3%; P = .04) on MRI.
“Differential diagnosis between PMR and sonographic rheumatoid arthritis is often complicated, but these MRI findings may be useful for this condition,” Kamada said.
“If recurrences can be predicted by gadolinium-enhanced MRI, rheumatologists can consider using anti-rheumatic drugs in the early stage for PMR patients. However, gadolinium-enhanced MRI has some disadvantages: high costs, adverse effects of gadolinium, and unavailability in some clinics, and ultrasonography is easier to use than MRI. We need to validate the results in a larger cohort and optimize and standardize the gadolinium-enhanced MRI procedure for PMR to apply in clinical practice.” – by Stacey L. Adams
Kamada K, et al. Abstract #1161. Gadolinium-enhanced magnetic resonance imaging in shoulders contributes accurate diagnosis and predicting recurrence to patients with polymyalgia rheumatica. Presented at ACR/ARP Annual Meeting, Nov. 8-13, 2019; Atlanta.
Disclosure: The researchers report no relevant financial disclosures.