[Polyradiculoneuritis in a diabetic patient. Ultrastructural study of a biopsy of a peripheral nerve].

We have made a study of a case of polyradiculoneuritis occurring in a diabetic. Clinically, symptoms were very similar to those in classical Guillain-Barré syndrome and respiratory complications necessitated a stay in a Respiratory Resuscitation Centre. Recuperation was slow but practically total. Ultrastructural changes noted in the roots and the peripheral nerves of patients suffering from Guillain-Barré syndrome are similar to those occurring in experimental allergic neuropathies. These changes are specific as the myelin takes on a fishnet appearance and, more important, the myelin is attacked by the projection of a mononucleate cell which has passed through the cytoplasm of the Schwann cells. We did not find this in our case. On the other hand, the lesions we found consisted of a mixture of common segmental demyelinization and axonal lesions, associated with marked Schwann cell hypertrophy coiled around most of the myelinized fibres. Such aspects are very like those found in certain diabetic neuropathies. The existence of significant microangiopathy which was present in this case is also an important, though not a decisive factor. We consider, therefore, that the syndrome of polyradiculoneuritis exhibited by this patient corresponds more closely to diabetic neuropathy than to a classical Guillain-Barré syndrome.