BRUGES, BELGIUM – Should children whose juvenile idiopathic arthritis has been diagnosed by ultrasound be treated as aggressively as those whose disease is diagnosed clinically?
Researchers presenting last week at the Pediatric Rheumatology European Society Congress in Bruges, Belgium, offered both cautious and enthusiastic perspectives on musculoskeletal ultrasound, the use of which has become ubiquitous in pediatric rheumatology.
Dr. Silvia Magni-Manzoni, of Fondazione San Matteo in Pavia, Italy, presented results from a recent Europe-wide survey that showed that ultrasound is now being used by more than 90% of pediatric rheumatologists in their practices, with 40% of them using the technology personally (Pediatr. Rheumatol. 2011;9[suppl. 1]:P47), according to Dr. Magni-Manzoni, who conducted the survey with her associates.
Their 10-question survey of nearly 400 pediatric rheumatologists achieved a 24% response rate, with answers from 37 countries. The investigators collected information about current use in daily practice, the clinical relevance of ultrasound, and areas for prospective development. Nearly three-quarters of respondents said that ultrasound allowed for the immediate improving of diagnosis of joint and soft tissue disease, and 70% said they considered ultrasound important for diagnosis, therapy monitoring, and research.
However, Dr. Magni-Manzoni further cautioned about using ultrasound to predict the course of disease and make treatment recommendations in juvenile idiopathic arthritis (JIA).
Ultrasound diagnoses have led to the reclassification of JIA patients’ disease subtypes; for example, patients considered by clinical exam to be oligoarthritic have been reclassified as polyarthritic after ultrasound. "Clinical and ultrasound examinations show different sensitivity in detecting synovitis, especially for peripheral joints," she noted.
Last fall, Dr. Magni-Manzoni presented findings at the annual meeting of the American College of Rheumatology that showed how pronounced the discrepancy between clinical and ultrasound-detected synovitis can be. Looking at 28 consecutive JIA patients (Arthritis Rheum. 2010;62[suppl. 10]:2220) determined by clinical exam to be in remission, Dr. Magni-Manzoni and colleagues found synovial hyperplasia in 75% of these patients following immediate referral for ultrasound examination.
But the decision to treat earlier or more aggressively in patients with ultrasound-detected symptoms depends on whether the ultrasound-detected synovitis, joint diffusion, or synovial hyperplasia will ultimately translate into disease flares, she said.
Dr. Magni-Manzoni said that her team has been exploring the question, following 39 consecutive JIA patients who had been diagnosed at baseline with clinically inactive disease, but after a separate ultrasound exam immediately afterward were found to have subclinical symptoms.
After 2 years’ follow up, Dr. Magni-Manzoni and colleagues found that subclinical, ultrasound-detected synovial symptoms were not predictive of disease flares. More than 60% of the study subjects still had clinically inactive disease, even though three-quarters of them had ultrasound-detected synovial hyperplasia, and two-thirds had joint diffusion, at baseline.
In a separate presentation in at the pediatric rheumatology congress, Dr. Athimalaipet V. Ramanan discussed his data showing that ultrasound can be used successfully in specific applications in JIA. Used as a visual guide, ultrasound can produce accurate and effective temporomandibular joint injections as evidenced from a small study (n = 39).
The study involved children with JIA that was complicated by temporomandibular joint (TMJ) involvement. TMJ arthritis symptoms resolved in 92% of children within 2 months after ultrasound-guided corticosteroid injection. However, Dr. Ramanan, of the Bristol Royal Hospital for Children in Bristol, U.K., also noted his group had not found ultrasound helpful in diagnosis (Pediatr. Rheumatol. 2011;9[suppl. 1]:P122).
Noting that data presented by other investigators at the congress showed that blind TMJ injections in children with JIA were as successful as ones that were guided radiologically, Dr. Ramanan told the congress that despite lingering uncertainties, "We think the possibility of problems will be a lot lower with guided rather than blind injections."
Dr. Magni-Manzoni told the congress that she agreed that ultrasound-guided joint injections, such as those investigated by Dr. Ramanan and colleagues, were "very useful" in clinical practice. She expressed the need for more guidelines and for better knowledge of ultrasound anatomy in healthy children as reference. "Ultrasound reference values are not known in healthy children," she said.
While ultrasound has considerable advantages for the pediatric rheumatologist, Dr. Magni-Manzoni said, "there are some challenges." Ultrasound is not sensitive in helping identify disease in all joints, such as TMJ, she pointed out; the quality of imaging depends on the type of machine used and the operator’s technique; and operators require constant practice.
Dr. Magni-Manzoni and Dr. Ramanan each reported that they had no disclosures related to their findings.