Simonati Alessandro, Fabrizi Gian Maria, Taioli Federica, Polo Alberto, Cerini Roberto, Rizzuto Nicolò
Department of Neurological and Visual Science, Section of Clinical Neurology, Policlinico GB Rossi, P.le LA Scuro 1, 37134 Verona, Italy.
J Neurol. 2002 Sep;249(9):1298-302. doi: 10.1007/s00415-002-0810-5.
In a patient affected with a slowly progressive, severe form of Dejerine-Sottas syndrome, symmetric enlargement of cranial nerves and focal hypertrophy of cervical and caudal roots were detected following MRI. Neuropathological features of the sural nerve disclosed a dramatic loss of myelinated fibres, with skewed-to-the-left, unimodal distribution of the few residual fibres, consistent with the diagnosis of congenital hypomyelination neuropathy. Genetic analysis revealed this condition to be associated with a heterozygous G to A transition at codon 167 in the exon 4 of the MPZ/P0 gene causing a Gly138Arg substitution in the transmembrane domain of the mature MPZ/P0 protein. Focal enlargement of the nerve trunks in demyelinating, hereditary motor and sensory neuropathies (HMSN) was previously reported in both asymptomatic and symptomatic cases with root compression, but peculiar to this case is the diffuse involvement of both cranial and spinal nerves. We believe that the relevance of nerve trunk hypertrophy in HMSN is probably underevaluated: therefore MRI investigation of the head and spine should be included in the diagnostic study of selected HMSN patients. Molecular analysis of peripheral myelin genes will help to rule out misdiagnosed cases.
在一名患有缓慢进展的严重型德热里纳 - 索塔斯综合征的患者中，MRI检查发现颅神经对称性增大以及颈段和尾段神经根局灶性肥大。腓肠神经的神经病理学特征显示有髓纤维显著丧失，少数残留纤维呈左偏态单峰分布，符合先天性髓鞘形成不足性神经病的诊断。基因分析表明，这种情况与MPZ/P0基因第4外显子密码子167处的杂合性G到A转换有关，导致成熟MPZ/P0蛋白跨膜结构域中的甘氨酸138被精氨酸取代。脱髓鞘性遗传性运动和感觉神经病（HMSN）中神经干的局灶性增大先前在无症状和有症状的神经根受压病例中均有报道，但该病例的独特之处在于颅神经和脊神经均有弥漫性受累。我们认为，HMSN中神经干肥大的相关性可能未得到充分评估：因此，对于选定的HMSN患者，诊断研究应包括头部和脊柱的MRI检查。对周围髓鞘基因的分子分析将有助于排除误诊病例。
