01801nas a2200337   4500000000100000008004100001260001300042653002200055653001000077653000900087653002500096653001500121653001100136653001200147653001600159653001700175653002200192653003900214653001600253100001500269700001400284700001100298700001400309700001400323700001600337245005200353300001000405490000700415520102700422022001401449       2004                            d  c2004 Sep10aAction Potentials10aAdult10aAged10aCase-Control Studies10aElectrodes10aHumans10aleprosy10aMiddle Aged10aNerve Fibers10aNeural Conduction10aPeripheral Nervous System Diseases10aSural Nerve1 aArruda APM1 aMarques W1 aFoss N1 aGarbino J1 aVirmond M1 aBarreira AA00aNear nerve potential of sural nerve in leprosy.  a571-40 v623 a<p>Leprosy neuropathy is characterized by initial involvement of the small nerve fibers, later followed by involvement of the large fibers, when routine nerve conduction studies become abnormal. To increase the diagnostic yield and precocity of these studies, we applied the near nerve technique to the sural nerve of 8 leprosy patients. Contrary to our expectations, the main component of the sural nerve sensory action potential was abnormal in all patients, but the minimum conduction velocity originating from small 3-6 mm fibers was normal or only mildly involved in three patients. Also, although Schwann cells are the first to be involved in leprosy, the results are suggestive of axonal degeneration instead of demyelination. To better understand the neurophysiology and physiology of leprosy and to increase the accuracy and precocity of the diagnosis, it will be necessary to investigate patients in the very early stages of the disease and to correlate these findings with the corresponding nerve pathology.</p>  a0004-282X