An Unusual Cause of Diffuse Bone Pain in a Long-Term Dialysis Patient: A Case Report of β2-Microglobulin Amyloid Arthropathy.

Dialysis-related amyloidosis (DRA) results from β2-microglobulin accumulation in patients on long-term hemodialysis, typically manifesting after 5-10 years. While well-documented in developed countries, reports from sub-Saharan Africa remain scarce. We report a 45 year-old Burkinabe man with 8 years of maintenance hemodialysis who presented with severe diffuse bone pain and inflammatory polyarthralgia affecting shoulders, hips, knees, and wrists. Physical examination revealed diffuse spinal tenderness and restricted painful joint mobility with bilateral positive Patrick's and key signs. Laboratory investigations showed elevated C-reactive protein and markedly elevated serum β2-microglobulin, with negative rheumatoid factor, anti-CCP antibodies, and antinuclear antibodies. MRI demonstrated characteristic band-like vertebral infiltration with preserved disc spaces and extensive nodular involvement of the sacrum, iliac wings, and proximal femurs. Despite unavailable bone biopsy, probable DRA diagnosis was established based on prolonged low-flux hemodialysis, markedly elevated β2-microglobulin, characteristic imaging, and exclusion of alternative diagnoses including AL and AA amyloidosis. Treatment with celecoxib 200 mg daily achieved significant improvement at 1 month follow-up. This case highlights probable DRA as an important cause of diffuse bone pain in younger African dialysis patients. Clinicians should maintain high suspicion for DRA in patients with polyarticular symptoms after long-term dialysis, utilizing β2-microglobulin measurement and MRI for diagnosis when histological confirmation is unavailable.