Redistribution of axoplasm in the motor root in experimental diabetes.

Early experimental diabetes is associated with a reduction in axonal caliber. To elucidate the changes of nerve caliber further, we investigated the proximal and distal regions of the anterior root of rats after 5 weeks of streptozocin-induced diabetes. After vascular perfusion fixation, the fifth lumbar motor root was excised and two 3-mm segments were isolated, one at the level of the spinal cord and one at the dorsal root ganglion. The areas of myelinated fibers and their axons were measured by point counting. Axons from diabetic mice were enlarged proximally as compared to the controls, and reduced distally. It has been hypothesized that the reduction in axonal caliber is caused by an impairment of axonal transport of structural proteins rather than by osmotic shrinkage. Our findings indicate a redistribution of axoplasm in the nerves of the diabetic mice and support the hypothesis that changes in the axonal transport of neurofilaments are responsible for the structural changes seen in early diabetes. Similar changes could also play a role in the development of neuropathy in man.

Dorsal root gangliopathia presenting with rapidly progressing sensory polyneuropathy.

A 52-year-old woman developed progressive sensory polyneuropathy leading to death in 1.5 years. Electromyography and peripheral nerve biopsy had revealed severe axonal degeneration. Neuropathological examination showed involvement of all dorsal root ganglia with loss of the bipolar nerve cells, degeneration of the remaining nerve cells, Nageotte's residual nodules, and scattered lymphocytes. The posterior columns of the spinal cord and the sensory spinal roots revealed secondary loss and degeneration of the nerve fibers. The etiology is unknown but an autoimmune-mediated reaction effecting the nervous system is strongly suggested.

[Renal involvement during intravenous treatment with acyclovir]. / Nyrepåvirkning under intravenøs behandling med aciklovir.

A woman aged 70 years developed reversible renal involvement during intravenous treatment with acyclovir. In order to prevent renal involvement during treatment with acyclovir, the following precautions are recommended: acyclovir should be infused slowly, regular control of renal function should be undertaken and the dosage should be reduced if evidence of renal involvement is found.

Clinical course and long-term prognosis of acute transverse myelopathy.

The clinical characteristics and course of acute transverse myelopathy (ATM) was studied. One patient developed multiple sclerosis. In 1 patient ATM was caused by tumour-cell embolization of the intramedullar vessels; 30 aged 12-74 years (median 36 years) had ATM of unknown course, of these, 13 had symptoms of a preceding viral-like infection, 18 had back-pain and 10 signs of spinal shock. The time from onset of ATM to maximum deficit varied from less than 1 h to 20 days. The thoracic region was the most common level of cord damage. Follow-up was possible in 29 cases; 2 died (2 and 8 months after onset), of the surviving 27 (follow-up 1-13 years, median 6 years) one third had a good outcome, one third a fair, while one third remained paraplegic, incontinent with severe sensory deficits. Back-pain and signs of spinal shock indicated a poor outcome.