Amyloidosis. Gross clinical specimen of sectioned kidney tissue in a case of amyloidosis. The kidney has been sliced in half along its long axis. The blood filtrating areas are pale, when they should be a healthy dark red. Microscopic examination of the tissue will confirm amyloidosis, a condition where one or more organs in the body accumulate life-threatening amyloid protein deposits. Kidney deposits are most common in primary amyloidosis, when abnormal bone marrow produces antibodies that cannot be broken down by the body. The antibodies are deposited as amyloid protein, leading to organ failure. Renal failure will require dialysis. The bone marrow is treated by chemotherapy.