P474. Infliximab induction therapy on AA amyloidosis associated with Crohn's disease: case report
A. Pukitis1, E. Ostrovskis1, T. Zake2, J. Pokrotnieks2, 1Pauls Stradins Clinical University Hospital, Gastroenterology Center, Riga, Latvia, 2Riga Stradins University, Riga, Latvia
Secondary systemic (AA) amyloidosis is a rare but serious complication of Crohn's disease (CD) with high mortality rate. Infliximab (IFX) is proven to induce clinical response and remission in CD. Unfortunately, only a few case reports have shown the therapeutic effects of IFX on CD-associated amyloidosis.
We report a case of a patient with CD complicated by AA amyloidosis, nephrotic syndrome, chronic kidney disease (CKD) and treated with IFX as induction therapy.
Patient is a 24-year-old man diagnosed with CD terminal ileitis at the age of 18 years. Thereafter, patient was treated with 5-aminosalicylate and azathioprine and maintained in clinical remission. Six years later he was admitted due to marked peripheral edema due to hypoalbuminemia, ascites, diarrhea and severe malnutrition. Laboratory tests showed nephrotic syndrome and renal biopsy was performed to confirm a diagnosis of AA amyloidosis. Serum amyloid A protein level was increased to 1082 mg/l (normal value (NV) <6.4 mg/l), C-reactive protein (CRP) to 13.0 mg/l (NV <5.0 mg/l), laboratory findings showed proteinuria 18.0 g/day, serum creatinine level 0.88 mg/dL and normal estimated glomerular filtration rate (eGFR) 113 ml/min/1.73m2. The patient received treatment with corticosteroids, azathioprine (2.5 mg/kg), enteral and parenteral nutrition to achieve remission of CD and additionally induction treatment with IFX was started to reduce the complications of AA. The level of eGFR (72 ml/min/1.73m2) revealed stage 2 CKD before treatment with IFX. Patient received IFX (5 mg/kg body weight) in three infusions at 0, 2, 6 weeks. There were no adverse effects from the medication. After the IFX induction therapy: serum amyloid A protein level was decreased to 22.5 mg/l (for 97.9%) and CRP to 3.9 mg/l, with improvement of bowel symptoms. There had been no notable changes in proteinuria, but significantly increased the reduction of renal function. Laboratory tests showed a progressive increase in serum creatinine level to 3.69 mg/dL and decreased eGFR to 4 stage of CKD.
In this rare CD combined with systemic AA case significant decrease of amyloid A protein level was achieved by the IFX induction treatment. An expected stabilization of renal function after IFX induction therapy was not achieved due to irreversible systemic amyloidosis damage. Theoretically longer term IFX treatment may delay the progression of amyloidosis and prevent further progression of the renal failure.