[Clinical features of a genetically identified spinal and  bulbar muscular atrophy pedigree].
Spinal and bulbar muscular atrophy (SBMA) is a rare X-linked motor neuron disease with significant phenotypic viability. Here, we present a genetically identified SBMA family without bulbar paralysis or androgen insensitivity. All four male patients presented with progressive lower motor neuron paralysis in all limbs, with distal extremities more dominant. None of them had bulbar palsy or androgen insensitivity. A consistently mild elevated blood creatine phosphokinase (CPK) levels were detected in all patients and the EMG showed a chronic neurogenic damage. Muscle biopsy of propositus indicated a typical neurogenic amyotrophy. Genetic testing for SMA of mutation in SMN1 was negative, while for SBMA of androgen receptor showed the increased CAG repeat in exon 1, suggesting that although bulbar symptoms and androgen insensitivity are characteristic symptoms of SBMA, they are not obligatory for the diagnosis. In adult males with a chronic motor neuron syndrome without upper motor neuron signs, even in absence of the classical features of androgen insensitivity or bulbar findings, genetic testing for SBMA should be strongly considered.
Department of Anesthesia, Xiangya School of Medicine, Central South University, Changsha 410013, China.
Zhe
Z
Wang
Department of Neurology, Xiangya Hospital, Central South Univercity, Changsha 410008, China.
Qihua
Q
Chen
Department of Neurology, Xiangya Hospital, Central South Univercity, Changsha 410008, China.
Qiuxiang
Q
Li
Department of Neurology, Xiangya Hospital, Central South Univercity, Changsha 410008, China.
Fangfang
F
Bi
D000328:Adult; D055534:Bulbo-Spinal Atrophy, X-Linked / Q000150:complications / Q000175:diagnosis* / Q000235:genetics*; D003402:Creatine Kinase / Q000097:blood; D005820:Genetic Testing; D006801:Humans; D008297:Male; D009046:Motor Neurons / Q000473:pathology; D009133:Muscular Atrophy / Q000209:etiology; D009154:Mutation / Q000235:genetics; D010243:Paralysis / Q000175:diagnosis / Q000209:etiology; D010375:Pedigree; D011944:Receptors, Androgen / Q000235:genetics*
C410798:AR protein, human; D011944:Receptors, Androgen; D003402:Creatine Kinase