Severe peripheral neuropathy and elevated plantar pressures causing foot ulceration in pituitary gigantism

We report two patients with treated pituitary gigantism and peripheral neuropathy, one of whom has chronic foot ulceration. Detailed neurophysiological assessment was performed on both patients. The patient with foot ulceration had clinical and neurophysiological evidence of severe neuropathy, whereas the patient without ulceration had only neurophysiological abnormalities. The sweating response to acetylcholine was markedly impaired in the feet of both patients, suggesting pedal autonomic denervation. Neither patient had evidence of diabetes mellitus and detailed investigation failed to reveal an alternative cause of peripheral neuropathy. Optical pedobarography revealed abnormally high pressure (> 10 kg/cm2) under the metatarsal heads of both patients, one such area coinciding with the area of ulceration. Thus in pituitary gigantism elevated plantar pressures may contribute to the development of foot ulceration when severe peripheral neuropathy is present. Furthermore, as in diabetes mellitus, impaired sweating may also increase the risk of ulceration as the resultant dry skin may develop fissures.