Fibromyalgia syndrome: experience in a pediatric rheumatology clinic

To report our experience of fibromyalgia syndrome (FMS) in pediatric rheumatology clinic settings.

Clinical and laboratory data were reviewed in all patients with FMS between March 1992 and March 1996. Patients with FMS and an underlying rheumatic disease were excluded from the study. At presentation and follow-up visits, all patients had a tender points (TP) count that was conducted by thumb palpation. Both the children and their parents were questioned concerning the presence of widespread pain or aching. All the patients fulfilled the ACR criteria for the diagnosis of primary FMS. All children were evaluated by a protocol that included relevant information on FMS. Telephone survey questionnaires were used for patients who missed some of their follow-up visits.

There were 59 children (47 F and 12 M) diagnosed with primary FMS. The mean age at onset was 13.7 years, and the mean age at diagnosis was 15.5 years. The mean duration of follow-up was 18.3 months. Diffuse aching was reported in 57 patients (97%), headaches in 45 (76%), and sleep disturbances in 41 (69%). Less common were stiffness in 17 (29%), subjective joint swelling in 14 (24%), fatigue in 12 (20%), abdominal pain in 10 (17%), and joint hypermobility and depression in 8 (14%) and 4 (7%) patients, respectively. The mean ESR was 15 mm/h, RF was negative in all patients, and ANA was positive (mean titer 1:160) in 17 patients. The mean initial TP count was 14.6. Nine patients were not available for follow-up. There were 50 patients available for follow-up and survey analysis, and of these 30 (60%) had improved, while 18 (36%) remained unchanged, and 2 (4%) became worse when compared with initial presentation. At the end of study follow-up, 37 patients (74%) were still taking medication (20 of them daily). Out of 25 patients whose TP counts were available at the end of follow-up, the mean TP dropped from 14.12 to 12.04 (p = 0.09) for the total group, and 14.05 to 10.84 (p < 0.01) for the patients who had improved. 22 out of 30 patients in the improved group and 7 out of 20 in the unchanged or worse group had continued active exercise programs (p < 0.001).

The clinical spectrum of FMS in children is similar to that of adults but with better outcomes. The TP count correlates with clinical status only in patients who had improved. Active exercise programs seem to correlate with better outcomes. Prospective and larger patient population studies, and a longer follow-up of children with FMS are needed to clarify these findings.