Khan Rafay, Hossain Mohammad A, Nai Qiang, Yousif Abdalla M, Sen Shraman
Department of Internal Medicine, Raritan Bay Medical Center, Perth Amboy, New Jersey, USA.
N Am J Med Sci. 2015 Aug;7(8):374-6. doi: 10.4103/1947-2714.163647.
Transient global amnesia (TGA) is an intriguing condition that classically presents with an abrupt onset of temporary complete anterograde amnesia and partial retrograde amnesia. Most individuals who experience such a form of amnesia usually have only one attack but recurrent attacks are possible. Most attacks last for a few minutes or few hours and the ability to lay down new memories may also be affected but gradually improves, leaving only a dense amnestic gap for the duration of the episode. There has been some discussion about the etiology behind TGA; however, there has yet to be a consensus with regard to any significant association.
We report the case of a 65-year-old male presenting with a sudden onset of memory loss that is typical of TGA and who was found to have elevated homocysteine levels. There has only been one other case previously reported that discussed a possible correlation between hyperhomocysteinemia and TGA. It is yet to be determined if increased homocysteine level is a significant risk factor for attacks of TGA.
Although it was first described more than half a century ago, it can still be misdiagnosed frequently as many physicians are not familiar with this condition. Furthermore, there are quite a few medical conditions that may cause sudden memory impairment, such as epilepsy and stroke, which make it difficult to distinguish them from this form of amnesia. The knowledge of these clinical identities is necessary for a high index of suspicion, which may lead to a meticulous medical evaluation as required for proper diagnosis.
短暂性全面性遗忘症(TGA)是一种引人关注的病症,典型表现为突然发作的暂时性完全顺行性遗忘和部分逆行性遗忘。大多数经历这种失忆形式的人通常只发作一次,但也有可能复发。大多数发作持续几分钟或几小时,形成新记忆的能力也可能受到影响,但会逐渐改善,在发作期间仅留下严重的失忆空白期。关于TGA背后的病因已有一些讨论;然而,对于任何显著关联尚未达成共识。
我们报告一例65岁男性病例,该患者突然出现TGA典型的记忆丧失,且发现其同型半胱氨酸水平升高。此前仅有另一例报告讨论了高同型半胱氨酸血症与TGA之间可能的关联。同型半胱氨酸水平升高是否是TGA发作的显著危险因素尚待确定。
尽管它在半个多世纪前就首次被描述,但仍经常被误诊,因为许多医生不熟悉这种病症。此外,有不少病症可能导致突然的记忆障碍,如癫痫和中风,这使得难以将它们与这种失忆形式区分开来。了解这些临床特征对于保持高度怀疑指数很有必要,这可能会促使进行适当诊断所需的细致医学评估。