Thrombocytopenia in systemic lupus erythematosus responsive to dapsone.

Comment The histological appearance of the amyloid (apple green birefringence under polarised light after staining with Congo red and resistance to pretreatment with potassium permanganate) in each case was consistent with dialysis related amyloidosis and not deposition of AA amyloid. In both patients immunohistology showed strong positivity of the amyloid deposits for P2 microglobulin and weaker positivity for P component. Stains for amyloid A protein and kappa and lambda light chains were negative. Though disease of the gastrointestinal tract resulting in haemorrhage or diarrhoea is well recognised in other types of amyloidosis,5 our findings represent a new aspect of dialysis related amyloidosis. This diagnosis should be considered in patients receiving long term haemodialysis who have obscure gastrointestinal disease, and it seems likely that other systemic complications of dialysis related amyloidosis will be reported.