METHODS: We describe a patient with onset of slowly progressive proximal weakness of the lower limbs after age 50, who maintains ambulation with the assistance of a cane at age 71.
RESULTS: Muscle biopsy at age 66 showed complex muscle fiber splitting, internalized capillaries, and vacuolar changes characteristic of autophagic vacuolar myopathy. Vacuoles stained positive for sarcolemmal proteins, LAMP2, and complement C5b-9. Ultrastructural evaluation further revealed basal lamina reduplication and extensive autophagosome extrusion. Sanger sequencing identified a known pathologic splice site mutation in VMA21 (c.164-7T>G).
CONCLUSIONS: This case expands the clinical phenotype of XMEA and suggests VMA21 sequencing be considered in evaluating men with LAMP2-positive autophagic vacuolar myopathy.
方法:我们描述了一名50岁后下肢缓慢进行性近端无力发作的患者,该患者在71岁时在手杖的帮助下保持步行。
结果:66岁时的肌肉活检显示复杂的肌纤维分裂,内化毛细血管,和自噬性空泡性肌病的空泡改变。液泡对肌膜蛋白染色阳性,LAMP2和补体C5b-9。超微结构评估进一步显示基底层重复和广泛的自噬体挤出。Sanger测序鉴定了VMA21中已知的病理剪接位点突变(c.164-7T>G)。
结论:该病例扩展了XMEA的临床表型,并建议在评估患有LAMP2阳性自噬空泡性肌病的男性时考虑VMA21测序。