Intensive generalized intracellular storage of PAS positive birefringent material with an unusual ultrastructure was found in 17 patients deceased after long-term haemodialysis. Both direct and indirect evidence documented intracellular storage and "condensation" of dextran administered repeatedly for hypotension during dialysis. Intensity of storage was related to residual diuresis of the patients and not to the number of dialyses. Identification of the material was enabled by digestion with dextranase. Dextran cytoplasmatic inclusions in macrophages resisted to common solvents but dissolved in alkalies. The storage occurred not only in lymph nodes, but also in interstitial tissues of other organs, such as the heart, adrenals, bone marrow and others. The relation of massive dextran storage to frequent complications was discussed. Quantity, morphogenesis and location of storage are instructive with respect to the common knowledge of storing systems.

School of General Medicine Charles University Prague