Drug-induced spongiform leucoencephalopathy, a case report with review of the literature.

A nineteen year-old girl developed rhabdomyolysis and central pyrexia after the ingestion of multiple drugs: amphetamines, benzodiazepines, methadone, ethanol, and cocaine. On admission, the patient was deeply comatose and during the hospitalisation asymmetrical spastic quadriparesis was noted. Brain biopsy was diagnostic of spongiform leucoencephalopathy. A review of the literature concerning drug-induced spongiform encephalopathy revealed a large amount of heroin-induced cases. The role of cocaine, however, is less well described. After prolonged hospitalisation, our patient improved clinically and radiologically and could be transferred to a rehabilitation center.

Further evidence for myelinated as well as unmyelinated fibre damage in a rat model of neuropathic pain.

A mononeuropathy, produced by ligation of the sciatic nerve in rats, has recently been proposed as an animal model of experimental pain and pain-related disorders (hyperalgesia and allodynia). We investigated quantitatively the morphological changes in myelinated and unmyelinated fibres of the sciatic nerves 2 weeks after ligation in rats exhibiting allodynia to thermal stimulation. There was a marked reduction in the number of large myelinated fibres distal to the ligature (711 +/- 34 compared with 5315 +/- 230 in normal nerves). We also found a significant loss of small myelinated fibres (2429 +/- 109 compared with 3197 +/- 308 in normal nerves), the remaining fibres of this type showing pathological properties. Finally, ultrastructural evidence of damage to unmyelinated fibres was found. The typical pattern of large clusters of normal unmyelinated axons was no longer present within most regions of the nerve. There was a significant reduction in the size of the unmyelinated fibres (0.41 micron +/- 0.15 compared with 0.71 micron +/- 0.08 in normal nerves), together with a twofold increase in their number per cluster. Hypotheses about the mechanism of thermal allodynia in this pain model therefore must take into account the fact that all fibre classes show pathological changes.

Magnesium deficiency as a cause of acute intractable seizures.

Clinical and experimental investigations have shown that magnesium depletion causes a marked irritability of the nervous system, eventually resulting in epileptic seizures. Although magnesium deficiency as a cause of epilepsy is uncommon, its recognition and correction may prove life-saving. Two case reports are presented which emphasize the importance of recognizing hypomagnesaemia in patients with acute intractable seizures.