Department of Psychogeriatrics, Kamiiida Daiichi General Hospital, Nagoya, Japan.
Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Psychogeriatrics. 2019 Sep;19(5):435-439. doi: 10.1111/psyg.12407. Epub 2019 Feb 7.
Visual hallucinations (VH) are one of the most common psychological symptoms of dementia with Lewy bodies (DLB). It is generally considered that the VH that occur in DLB usually disappear when patients try to touch imaginary objects. However, DLB patients also sometimes experience tactile hallucinations (TH). To the best of my knowledge, this is the first report to comprehensively describe the TH experienced by DLB patients.
I searched the literature for case reports that described TH in Parkinson's disease (PD), PD dementia, or DLB. There were four reports regarding TH in PD, one of which was a review article published in 2017. I described the clinical courses of five representative cases of DLB in which TH were associated with VH, and then compared the characteristics of the TH experienced in DLB with those of the TH encountered in previously reported cases of PD.
The TH experienced by the DLB patients had very similar characteristics to the TH experienced by PD patients. However, the TH of the DLB patients differed from those of PD patients in the following respects: (i) when the DLB patients tried to touch the imaginary objects, they often did not disappear; (ii) the imaginary objects experienced by the DLB patients sometimes exhibited characteristic hardness and temperature; and (iii) the imaginary objects experienced by the DLB patients were often influenced by the patients' behaviour, which in turn led to further hallucinations.
Based on the abovementioned characteristics of the hallucinations of DLB patients, I propose that these phenomena represent a novel psychopathological entity, which I shall temporarily refer to as, 'strengthening of VH by TH'.
视幻觉（VH）是路易体痴呆（DLB）最常见的心理症状之一。一般认为，DLB 患者出现的 VH 通常会在患者试图触摸想象中的物体时消失。然而，DLB 患者有时也会出现触觉幻觉（TH）。据我所知，这是首次全面描述 DLB 患者经历 TH 的报告。
我对描述帕金森病（PD）、PD 痴呆或 DLB 患者 TH 的病例报告进行了文献检索。有 4 篇关于 PD 患者 TH 的报告，其中 1 篇是 2017 年发表的综述文章。我描述了 5 例具有 VH 相关 TH 的典型 DLB 患者的临床病程，然后比较了 DLB 患者经历的 TH 与之前报道的 PD 患者经历的 TH 的特征。
DLB 患者的 TH 与 PD 患者的 TH 具有非常相似的特征。然而，DLB 患者的 TH 与 PD 患者的 TH 有以下不同之处：（i）当 DLB 患者试图触摸想象中的物体时，它们通常不会消失；（ii）DLB 患者所经历的想象中的物体有时具有特征性的硬度和温度；（iii）DLB 患者所经历的想象中的物体经常受到患者行为的影响，从而导致进一步的幻觉。
基于 DLB 患者幻觉的上述特征，我提出这些现象代表了一种新的精神病理学实体，我将其暂时称为“TH 增强的 VH”。
