Preclinical Polymodal Hallucinations for 13 Years before Dementia with Lewy Bodies

Abstract

Objective. We describe a case of dementia with Lewy bodies (DLB) that presented long-lasting preclinical complex polymodal hallucinations. Background. Few studies have deeply investigated the characteristics of hallucinations in DLB, especially in the preclinical phase. Moreover, the clinical phenotype of mild cognitive impairment-(MCI-) DLB is poorly understood. Methods. The patient was followed for 4 years and a selective phenomenological and cognitive study was performed at the predementia stage. Results. The phenomenological study showed the presence of hypnagogic and hypnopompic hallucinations that allowed us to make a differential diagnosis between DLB and Charles Bonnet syndrome (CBS). The neuropsychological evaluation showed a multiple domain without amnesia MCI subtype with prefrontal dysexecutive, visuoperceptual, and visuospatial impairments and simultanagnosia, which has not previously been reported in MCI-DLB. Conclusions. This study extends the prognostic value of hallucinations for DLB to the preclinical phases. It supports and refines the MCI-DLB concept and identifies simultanagnosia as a possible early cognitive marker. Finally, it confirms an association between hallucinations and visuoperceptual impairments at an intermediate stage of the disease course and strongly supports the hypothesis that hallucinations in the earliest stages of DLB may reflect a narcolepsy-like REM-sleep disorder.

Clinical presentations and diagnostic application of proposed biomarkers in psychiatric‐onset prodromal dementia with Lewy bodies

“…There have been clinical case reports of various types of psychosis, including isolated visual hallucinations, oral cenesthopathy, erotomania, and delusional infestation, in patients who obtained a final diagnosis of DLB. 50,[66][67][68][69][70][71][72][73][74] Although onset ages and types of psychosis were different, there was the various timing of cognitive decline relative to the onset of psychosis.…”

Cognitive Impairment in Neurodegenerative Movement Disorders

“…44 Visual hallucinations are also the best predictor that the correct pathological diagnosis is DLB (positive predictive value of 0.83), as opposed to another pathology causing dementia, and sometimes they are the only initial symptom in mild dementia stages. 53,54 Since DLB patients are able to report the visual hallucinations, it is very important to specifically screen for this symptom during the clinical interview. Similarly, in the course of the disease, DLB patients may experience hallucinations in other modalities and/or systematized delusions.…”

Organische Psychosyndrome

“…Auch in den Fr€ uhphasen demenzieller Erkrankungen (im MCI-Stadium) können € uberwiegend optische komplexe und bewegte Halluzinationen (in der Regel Menschen oder Tiere) beobachtet werden. Im Einzelfall können komplexe Halluzinationen einer manifesten Lewy-Körperchen-Demenz um mehr als 10 Jahre vorausgehen (Abbate et al 2014). Klinisch scheinen akustische Halluzinationen häufig dialogischer Natur zu sein, die oft mehrere Personen umfassen und mit visuellen Halluzinationen einhergehen können.…”