type . Systemic amyloidosis of beta 2 microglobulin

A patient receiving haemodialysis for 15 years developed systemic amyloidosis of I2 microglobulin type. Noticeable deposits of amyloid were present in the myocardium, intervertebral discs, joint cartilages and tendons. Less conspicuous amounts were present in blood vessel walls in the lungs, liver, adrenal glands and brain, and within the stroma of the prostate, testis and kidney, often with foci of calcification. Department of Pathological Sciences, Stopford Building, University of Manchester M13 9PT K Mazanec J McClure C J Bartley M J Newbould Artificial Kidney Unit, University Hospital of South Manchester P Ackrill Correspondence to: Professor J McClure Accepted for publication 20 January 1992 Many of the bone, joint, and connective tissue disorders experienced by patients receiving long term haemodialysis are due to the deposition of I2 microglobulin amyloid in the affected sites.' Most reported cases describe localised amyloid deposits and the carpal ligament is a common site.2There have been a few cases of more extensive deposition.3 Case report A 59 year old man had had chronic renal failure treated by haemodialysis for 15 years. At various points during this time he had sustained a failed cadaveric renal transplantation, tertiary hyperparathyroidism treated by ... ..,;....... ... i}. Figure I Deposits of amyloid showing positive reactions for the presence of a_ microglobin (arrowed) (AB-PAP). parathyroidectomy, a myocardial infarct and a transitional cell carcinoma of the urinary bladder. His last illness was septicaemia (Staphylococcus aureus) and he died suddenly. At necropsy the heart weighed 794 g. There was extensive calcification of the mitral valve ring and the mitral valve cusps with evident mitral incompetence. There was bilateral pulmonary oedema and prominant passive venous congestion of the spleen and liver. In addition to the visceral organs, the vertebral column, iliac bone, both knee joints, both shoulder joints and the right carpus were removed, examined macroscopically, and sampled for histological examination. All tissue samples were fixed in 10% formalin, embedded in paraffin wax, stained with either haematoxylin and eosin or alkaline Congo red, or alkaline Congo red after pretreatment with potassium permanganate. Those samples considered positive for amyloid deposits were studied by a standard indirect immunoperoxidase technique with the following: anti-AA, anti-P-component, anti-x and anti-k light chains, anti-prealbumin and antifibrin antibodies. Histologically, in the myocardium there was extensive fibrosis with calcification. Eosinophilic material with the staining characteristics of amyloid of P2 microglobulin type was present in some areas (fig 1). A recent myocardial infarct with a related microscopic abscess was also present. Large deposits of amyloid were present in different joint cartilages and menisci, intervertebral discs, and adjacent bone. In the latter site there was a prominent multinucleated giant cell reaction (fig 2). Small amounts of amyloid were further found in blood vessel walls of the lungs, liver, adrenal glands and brain and within the stroma of the prostate, testis, and kidney, often together with foci of calcification, which were discovered almost in each organ examined. The immunostaining results showed that only P2 microglobulin and P-component were present in the amyloid deposits. None of the other molecules sought was found in these deposits. Discussion Amyloids of prealbumin, light chain, or amyloid A type are capable of systemic deposition. P2 microglobulin amyloid is usually considered to be localised to articular and juxta-articular structures, and it was initially assumed that any deposition in extra-articular sites was low in 832 group.bmj.com on June 22, 2017 Published by http://jcp.bmj.com/ Downloaded from