Musculoskeletal manifestations in childhood-onset systemic lupus erythematosus: an in-depth exploration

Abstract

Background: Childhood-onset systemic lupus erythematosus (c-SLE) is a multifaceted autoimmune disorder predominantly affecting the musculoskeletal (MSK) system. This investigation delineated the spectrum and sequelae of MSK involvement in c-SLE patients. Methods: This retrospective analysis included SLE patients aged ≤ 18 years treated at a tertiary center between 2009 and 2019. Data were extracted from electronic health records. Results: The cohort comprised 321 SLE patients (mean age 13.2 ± 2.5 years, 91.3% female). MSK manifestations were observed in 134 (41.7%) individuals, with joint pain universally present, followed by joint swelling in 32.1% and morning stiffness in 9.7%. Arthritis was documented in 52 (38.8%) patients, whereas 82 (61.2%) had arthralgia. Symmetrical joint involvement was observed in 96 (71.7%) subjects. The knees, wrists, and fingers were most commonly affected, with incidences of 43.3%, 40.3%, and 33.6%, respectively. Neither erosive arthritis nor Jaccoud’s arthropathy was detected. MSK symptoms were significantly correlated with older age at diagnosis, the presence of non-scarring alopecia, neuropsychiatric manifestations, and elevated SLE disease activity index scores at diagnosis. Over a median follow-up of 53.6 months (IQR 26.1–84.6), five patients developed septic arthritis or osteomyelitis, and avascular necrosis was identified in 16 (4.9%) patients. Conclusions: Nearly half of c-SLE patients demonstrated MSK manifestations, chiefly characterized by symmetrical involvement of both large and small joints without evidence of erosive arthritis or Jaccoud’s arthropathy. Avascular necrosis is a critical concern and warrants close monitoring.