[Pathological features of muscles and peripheral nerves of Kennedy's disease: a report of 12 cases].

OBJECTIVE

To explore the pathological features of muscles and peripheral nerves of Kennedy's disease (KD).

METHODS

A total of 12 male patients were selected at our department from January 2006 to October 2014. Their definite diagnoses of KD were made by genetic testing of androgen receptor. Their average age was (52 ± 10) years old. All onset sites were lower limbs. Serum creatine kinase levels were elevated in varying degrees of 209-3 600 U/L. Electrophysiological examination revealed generalized neurogenic damage and impaired peripheral motor and sensory nerves. Biopsies were performed on biceps brachii (n=8), gastrocnemius (n=3), quadriceps femoris (n=1) and sural nerve (n=4).

RESULTS

The major muscular pathological features were neurogenic pathological changes. Some patients had myopathic changes, showing necrotic fibers, regenerating fibers, fiber splitting, vortex-like fibers, central nuclei and reduced oxidase activities. Sural nerve pathology of 4 patients showed a loss of myelinated nerve fibers, as well as axonal degeneration, regeneration clusters and thin myelinated fibers. Electron microscopy examination showed axonal degeneration, regeneration clusters, thin myelinated fibers and onion bulbs-like pathological changes.

CONCLUSION

KD has myopathic changes with an impairment of chronic axonal and demyelinating sensory nerves.