Tuesday, June 17, 2008

Hereditary Amyloidosis

I saw a patient in Transplant Clinic today with a strong family history of chronic kidney disease requiring dialysis and periodic fevers. She was coming to the Transplant Clinic because she wants to be considered for a potential renal transplant. Both the patient, her brother, her sister, and her father--a family of English-Irish descent--had a history of high fevers and progressive renal disease. Biopsy of the kidneys previously has revealed nodular deposits with positive apple-green birefringence with Congo Red staining.

It turns out this family has TNF Receptor-Associated Periodic Syndrome (TRAPS), also known as Hibernian Fever, which is due to mutations in the gene encoding for tumor necrosis factor receptor 1. The disease manifests as recurrent fevers and a chronic inflammatory state, similar to other hereditary periodic fever syndromes such as familial Mediterranean fever (FMF) or Muckle-Wells Syndrome, and the reason these individuals may get renal disease is due to AA amyloidosis. Patients with TRAPS can (logically enough) be treated with etanercept (Enbrel), a monoclonal antibody against TNF and prednisone. The patient described is being considered for a cadaveric renal transplant but has been warned that there is a strong possibility that amyloid deposition in her future allograft could occur.

No comments: