Background: Amyloidosis may complicate autoinflammatory diseases (AID). We aimed to evaluate the renal biopsy findings, and clinical and laboratory parameters in patients with AID-associated amyloidosis who have responded to anti-interleukin 1(IL1) treatment.
Methods: Two children with systemic juvenile idiopathic arthritis and one with cryopyrin-associated periodic syndrome diagnosed as having reactive amyloidosis were treated with anti-IL1 drugs. The renal histopathological findings at the time of diagnosis of amyloidosis and after the onset of anti-IL1 were evaluated according to the amyloid scoring/grading system.
Results: The median age of disease onset and diagnosis of amyloidosis were 3 and 12 years, respectively. Anakinra was started in all; however, anakinra caused a local cutaneous reaction in one, thus canakinumab was commenced. Proteinuria improved in all. Control renal biopsies were performed a median of 3 years after the first biopsies. The renal amyloid prognostic score did not improve in patient 1, and progressed in patients 2 and 3. The renal amyloid grade progressed in patient 2.
Conclusions: This is the first series demonstrating progression of renal tissue damage after the improvement of proteinuria with anti-IL 1 in AID-associated amyloidosis. Anti-IL1 drugs are important to prevent further amyloid accumulation; however, new treatment strategies are needed to target the amyloid deposits.
Keywords: Anakinra; Anti-interleukin 1; Autoinflammatory disease; Proteinuria; Renal amyloidosis.