Intermittent Claudication as the Presenting Symptom in Primary Amyloidosis

B.F. Schneider, PhD, MD, Department of Radiology, Radiation Oncology – Box 383, University of Virginia Health Science Center, Charlottesville, VA 22908 (USA) Intermittent claudication is a symptom of circulatory insufficiency that develops primarily in muscles of the lower extremities. It is most frequently associated with atherosclerosis, but may also occur with other vascular disorders such as giant cell arteritis, thromboangiitis obli-terans, Takayasu disease and Raynaud disease, as well as with stenosis of the lumbar spinal canal [1]. Here we report on a patient whose symptoms of intermittent claudication appear to be due to amyloid angiopathy; moreover, this appears to be the first symptom of this patient’s previously unrecognized primary amyloidosis. A 77-year-old man presents with a 4-year history of exercise-induced pain in his calf muscles bilaterally, extending to his thighs and buttocks. These symptoms now occur after walking approximately 50 yards and are relieved completely by resting for a few minutes. He also has pain in both upper extremities with minimal exercise, relieved by rest. Approximately 18 months ago he underwent a la-minectomy of L4 and decompression of L3-4 and L4-5 for spinal stenosis, but his symptoms remained unchanged. Neurologic reevaluations indicate that his persisting symptoms of intermittent claudication are not due to spinal stenosis. Multiple peripheral vascular studies, including an angiogram and ankle brachial index with exercise, have all indicated no major vascular obstruction. On physical exam he is normotensive, with no bruits and nontender temporal arteries. The liver is moderately enlarged, and the spleen is not palpable. Straight leg raise is negative. Motor and sensory examinations are intact throughout. There is some degree of cyanosis of his feet, particularly in the dependent position, and the distal extremities are cool, but distal pulses and capillary refill are normal. Laboratory tests reveal a blood urea nitrogen of 28 mg/dl and a creatinine of 1.7 mg/dl. Blood count reveals a mild anemia with a hemoglobin of 11.9 g/dl and hematocrit of 36%. The white blood cell count is 4,300/ml with 22% lymphocytes, 17% monocytes, 5% eosinophils and 1% ba-sophils. The platelet count is 37,000/ml. Serum protein electrophoresis shows increased ß-glob-ulins (1.19 g/dl, normal 0.6-1.10) with normal levels of albumin, αr, α2and γ-globulins. Quantitative levels of IgG, IgA, IgM, k and λ