Infliximab and Colchicine Therapy in the Treatment of Systemic Secondary Amyloidosis in Crohn’s Disease

Abstract

Introduction: Systemic secondary (AA) amyloidosis is a rare complication of long-standing Crohn’s disease (CD) with an incidence of 0.9-3%. At present, no established standard of treatment exists for AA amyloidosis in CD. We present a case of AA amyloidosis with renal and colonic involvement in a patient with CD who experienced both improvement in renal function and complete histologic resolution of colonic amyloidosis after infliximab (IFX) and colchicine therapy. Case Report: A 50-year-old male with refractory CD on 5-aminosalicylic acid, 6-mercaptopurine, and chronic steroid therapy was noted to have acute onset anasarca in the fall of 2007. Laboratory studies revealed serum creatinine of 1.2 mg/dL, albumin of 1.3 gm/dL, and proteinuria of 8,258 mg over 24 hours, consistent with nephrotic syndrome. Renal biopsy was performed, and immunohistochemical staining was positive for serum amyloid A, confirming the diagnosis of AA amyloidosis. The patient was subsequently started on IFX and colchicine therapy. In 3 months, he noted significant clinical improvement in gastrointestinal symptoms and was able to wean off of steroids; however, he continued to have nephrotic-range proteinuria. IFX and colchicine therapy was continued with routine follow-up. Gradually, the patient’s anasarca resolved and his renal function was stable, with only trace protein on urinalysis. A colonoscopy with biopsy in July 2009 revealed chronic active colitis with amyloidosis of the rectum, despite a long period of clinical remission. At this time, the patient was continued on IFX and colchicine. He underwent repeat colonoscopy with biopsy in November 2011, which revealed colonic inflammation, but no evidence of rectal amyloidosis. Another colonoscopy in 2012 again showed colonic inflammation with complete resolution of amyloidosis in the rectum. Given the patient’s overall state of clinical remission and stable renal function, colchicine was subsequently discontinued and he was maintained on IFX therapy alone. Discussion: Few case reports have documented clinical improvement of AA amyloidosis in CD patients receiving IFX; however, complete histologic resolution of gastrointestinal amyloidosis after IFX and colchicine therapy has not been previously reported in the literature. It is unclear if this finding occurs in other affected organ systems. Further research is necessary to identify this phenomenon, which has important implications in the future medical management of AA amyloidosis in CD patients. Additionally, AA amyloidosis is a serious complication; routine histopathologic evaluation of bowel biopsy specimen may aid in early diagnoses and treatment of gastrointestinal amyloidosis, as well as assess response to therapy.