Clinical presentation and course of a patient with Schnitzler syndrome and reactive AA amyloidosis treated with anticlone therapy followed by IL-1 blocking treatment. A 55-year-old man was diagnosed with amyloidosis by renal biopsy. (A) During the previous 30 years, he had chronic nonpruritic urticarial rash associated with recurrent fever (up to 39°C) and arthralgia. Proteinuria and subsequent nephrotic syndrome were associated with profound postural hypotension and diarrhea. (B) A small (8 g/L) IgMκ monoclonal protein was detected with a 6% clonal bone marrow lymphoplasmacytic infiltrate. Proteinuria was 4.6 g per 24 hours, and there were no signs of amyloid cardiac or liver involvement. Amyloid deposits were detected in the abdominal fat, which reacted with anti-serum amyloid A (anti-SAA) apolipoprotein antibodies and not with anti-κ and anti-λ light chain antibodies. (C) A diagnosis of AA amyloidosis due to Schnitzler syndrome with kidney and autonomic nervous system involvement was made, and the patient was treated with cyclophosphamide, rituximab, and dexamethasone, with improvement of clinical symptoms and reduction of SAA and proteinuria. After 18 months, an increase in SAA and proteinuria accompanied an exacerbation of symptoms, and the patient was placed on anakinra, resulting in complete clinical remission and normalization of SAA and proteinuria. Apr, April; CDR, cyclophosphamide, rituximab, and dexamethasone; Oct, October; SAA, serum amyloid A.