A systematic study of the upper cervical spine was performed using magnetic resonance imaging in 25 patients (15 men and 10 women) who had been undergoing hemodialysis for more than 10 years. Seven pseudotumors of the periodontoid soft tissue were disclosed, which were similar to the pannus recently described in rheumatoid arthritis. Bone cystic radiolucencies were observed in association with these pseudotumors in 5 patients. The radiolucencies were located in the atlas (1 in the lateral mass and 1 in the anterior branch) and in the axis (3 in the odontoid process and 1 in the vertebral body). No horizontal or vertical atlantoaxial subluxation was demonstrated. These features were observed only in patients who had amyloid arthropathy. They could be a frequent, yet thus far little-recognized, feature of beta 2-microglobulin amyloidosis.
Administration of recombinant erythropoietin constitutes a revolution in treatment of the anemia of chronic dialysis patients. Such treatment has been anxiously awaited. Its realization has been possible thanks to the spectacular progress allowed by the newly developed techniques of recombinant genetics. Correction of this type of anemia can be obtained rapidly and permanently if treatment is continued without interruption. It is followed by a remarkable transformation of the patient's physical and psychic status. The occurrence of certain side effects (e.g., elevation of blood pressure and an increased tendency toward vascular thrombosis), however, requires increased awareness in the follow-up of patients at risk and adaptation of erythropoietin administration to individual needs.