Treatment escalation patterns to start biologics in refractory moderate juvenile dermatomyositis among members of the Childhood Arthritis and Rheumatology Research Alliance

BACKGROUND

Despite new and better treatments for juvenile dermatomyositis (JDM), not all patients with moderate severity disease respond adequately to first-line therapy. Those with refractory disease remain at higher risk for disease and glucocorticoid-related complications. Biologic disease-modifying antirheumatic drugs (DMARDs) have become part of the arsenal of treatments for JDM. However, prospective comparative studies of commonly used biologics are lacking.

METHODS

The Childhood Arthritis and Rheumatology Research Alliance (CARRA) JDM biologics workgroup met in 2019 and produced a survey assessing current treatment escalation practices for JDM, including preferences regarding use of biologic treatments. The cases and questions were developed using a consensus framework, requiring 80% agreement for consensus. The survey was completed online in 2020 by CARRA members interested in JDM. Survey results were analyzed among all respondents and according to years of experience. Chi-square or Fisher's exact test was used to compare the distribution of responses to each survey question.

RESULTS

One hundred twenty-one CARRA members responded to the survey (denominators vary for each question). Of the respondents, 88% were pediatric rheumatologists, 85% practiced in the United States, and 43% had over 10 years of experience. For a patient with moderately severe JDM refractory to methotrexate, glucocorticoids, and IVIG, approximately 80% of respondents indicated that they would initiate a biologic after failing 1-2 non-biologic DMARDs. Trials of methotrexate and mycophenolate were considered necessary by 96% and 60% of respondents, respectively, before initiating a biologic. By weighed average, rituximab was the preferred biologic over abatacept, tocilizumab, and infliximab. Over 50% of respondents would start a biologic by 4 months from diagnosis for patients with refractory moderately severe JDM. There were no notable differences in treatment practices between respondents by years of experience.

CONCLUSION

Most respondents favored starting a biologic earlier in disease course after trialing up to two conventional DMARDs, specifically including methotrexate. There was a clear preference for rituximab. However, there remains a dearth of prospective data comparing biologics in refractory JDM. These findings underscore the need for biologic consensus treatment plans (CTPs) for refractory JDM, which will ultimately facilitate comparative effectiveness studies and inform treatment practices.

Juvenile dermatomyositis at diagnosis: clinical characteristics of 79 children

OBJECTIVE

To evaluate demographic and clinical characteristics, duration of time between disease onset (date of first rash and/or weakness), and diagnosis/therapy, as well as socioeconomic status, of children with newly diagnosed juvenile dermatomyositis (JDM).

METHODS

Structured telephone interview of families of a cohort of 79 children with JDM: interval between onset of symptoms to diagnosis, median of 3 months (range 0.5-20.0).

RESULTS

At diagnosis, all the children had rash (100%) and proximal muscle weakness (100%); 58 (73%) had muscle pain; 51 (65%) fever; 35 (44%) dysphagia; 34 (43%) hoarseness; 29 (37%) abdominal pain; 28 (35%) arthritis; 18 (23%) calcinosis, and 10 (13%) melena. Muscle derived enzymes were normal in 10% of the children. Of the 43 children who had an electromyogram (EMG), 8 (19%) had normal results. Fifty-one children had a muscle biopsy; the results were normal/nondiagnostic in 10 (20%). Median time from disease onset to diagnosis was different between racial groups: Caucasians (n=59) 2.0 months: for minorities (n=20), 6.5 months, (p=0.0008). The median time from disease onset to therapy was: Caucasians. 3.0 months; minorities, 7.2 months (p=0.002). Report of calcinosis was associated with increased time to diagnosis and therapy (p=0.04). In the 33 children whose first symptom occurred in June-September, rash preceded or accompanied onset of muscle weakness in 83% (n=27). Ninety-one percent of the children were given steroid therapy and 9% received methotrexate as well.

CONCLUSION

The results of an undirected site for muscle biopsy or EMG may not be diagnostic. Minority children had a longer interval between first JDM symptom and diagnosis/therapy than Caucasian children. Delay in diagnosis/therapy was associated with calcinosis.

New-onset juvenile dermatomyositis: comparisons with a healthy cohort and children with juvenile rheumatoid arthritis

OBJECTIVE

To determine, in a case-control study, if patients with new-onset juvenile dermatomyositis (juvenile DM) have increased symptoms prior to onset, exposure to certain environmental conditions, frequency of familial autoimmune diseases, or antibody titers, compared with 2 control groups.

METHODS

A structured interview with the families of 80 children with juvenile DM, 40 children with juvenile rheumatoid arthritis (JRA), or 23 healthy children, from the same geographic area as the children with juvenile DM, was conducted. All children's sera were tested for antibody to Toxoplasma gondii, herpes simplex virus (HSV), or coxsackievirus B (CVB).

RESULTS

A high proportion of children with juvenile DM had constitutional symptoms 3 months before the disease-onset date (P = 0.013 versus control children). Children with JRA had more relatives with rheumatoid arthritis (P = 0.0001) and pernicious anemia (P = 0.003) than did children with juvenile DM or healthy children. Among children < or =7 years of age, elevated enteroviral titers were more frequent in those with juvenile DM (81%) and in healthy controls (90%) than in those with JRA (64%), suggesting a common environmental exposure. Titers to T gondii, HSV, or CVB 1-6 were normal.

CONCLUSION

Frequencies of familial autoimmune disease, exposure to environmental factors, or elevated antibody titers to T gondii, HSV, or CVB are not increased in juvenile DM. Children with juvenile DM do have symptoms of illness 3 months before the disease-onset date, and young patients have elevated enteroviral titers, as do young geographic controls.

Psychosocial effects of juvenile rheumatic disease. The family and peer systems as a context for coping

The psychosocial effects of juvenile rheumatic diseases and disease activity were examined among 24 children and their families (12 children with a rheumatic disease and 12 children with no chronic illness). Each child with rheumatic illness was paired with a healthy control child nominated by their classroom teacher. Family and child functioning was assessed through measures of competence, coping, and adjustment and through direct observation of social functioning with peers at school. Multivariate and univariate analyses were performed to examine scores on the assessment measures, percentages of time spent in peer activities, and frequency scores for types of peer interactions. The results of these analyses indicated that juvenile rheumatic disease (JRD) is not associated with detrimental psychosocial outcomes. Instead, the results indicated that JRD children and their families actively utilize multiple coping strategies. These findings stress the importance of including and examining the family and peer systems as contexts for coping in future research.

Physical maturity screening for participation in sports

In an effort to develop screening criteria to allow nonphysicians to detect physically immature boys prior to interscholastic sports competition, 364 male adolescents were studied as part of their group preparticipation health evaluation. Handgrip and self-assessed Tanner stage were measured, in addition to the routine preparticipation health evaluation procedures. Of the 118 boys who were Tanner 3 or less (immature), 103 (87%) had weak grips (less than 55 lb [24.9 kg]), and 88 (75%) rated themselves as Tanner 3 or less. Of the 246 boys who were greater than Tanner 3 (mature), 223 (91%) had strong grips (greater than or equal to 55 [24.9 kg]), and 229 (93%) rated themselves as greater than Tanner 3. Six of the 118 immature boys (5%) had both a strong grip and mature self-assessed Tanner stage; three of the 246 mature boys (1%) had both a weak grip and an immature self-assessed Tanner stage. Only 67 of 364 (18%) boys had grips and self-assessed Tanner staging that were discordant. Use of grip strength and self-assessed Tanner staging may obviate the need for physician assessment of Tanner stage for the majority of adolescent boys prior to participation in collision sports.

The hypermobility syndrome

The hypermobility syndrome has been recognized as a definitive diagnostic entity among children referred to a Pediatric Arthritis Clinic with musculoskeletal complaints. The diagnosis of hypermobility was made by the ability of the patients to perform at least three of the following maneuvers: (1) extension of the wrists and metacarpal phalanges so that the fingers are parallel to the dorsum of the forearm; (2) passive apposition of thumbs to the flexor aspect of the forearm; (3) hyperextension of elbows (greater than or equal to 10 degrees); (4) hyperextension of knees (greater than or equal to 10 degrees); (5) flexion of trunk with knees extended so palms rest on the floor. Of 262 patients, 15 (5.7%) referred to an arthritis clinic between January 1979 and July 1981 were subsequently determined to have hypermobility as the basis for their rheumatic complaints. Three of these 15 had concomitant juvenile arthritis. The presenting complaint of pain was most often localized to the knees, hands, and fingers. Arthritis and elevated ESRs were not seen except in the three patients who had concomitant juvenile arthritis. All patients responded to physical therapy and nonsteroidal analgesic anti-inflammatory drugs. This is an entity not sufficiently well recognized as a source of musculoskeletal complaints in the United States. It will usually respond well to reassurance and symptomatic therapy.

The prevalence of juvenile arthritis

A secondary analysis of two new large practitioner surveys, one national and one local, showed the prevalence of juvenile arthritis to be between 0.16 and 0.43 cases per 1,000 children. These rates compare quite closely with the majority of reports both in the United States and the world. We believe the prevalence of juvenile arthritis is between 0.2 and 1 case per 1,000 children (13,000--63,000 children), with the best estimate being about 0.5 cases per 1,000 children. Based on the 1980 census data, this latter estimate means there are approximately 32,00 children with juvenile arthritis in the United States.