A Bird's-Eye Perspective: An Unusual Case of Very Late-Onset Schizophrenia-Like Psychosis With Visual Hallucinations Included in Its Manifestations Versus the Dementia Prodrome.

Very late-onset schizophrenia-like psychosis (VLOSLP) is still a paradox; certain characteristics such as episodic progression of psychosis including delusions and hallucinations involving various modalities, as well as the absence of negative symptoms, are strongly predictive of VLOSLP. We describe an interesting case of a 61-year-old male who presented with a second episode of psychosis along with mild to moderate cognitive impairment like having difficulty in buttoning for over eight months at our tertiary care hospital. Previously, during the first episode, he was treated by a private practitioner; adequate doses for an adequate duration of two atypical antipsychotics were given; and up to 25% global improvement was reported by the caregiver. During the current episode, he experienced delusions, in which he had a conviction that a "WIFI" was capable of "thought-making" functions. During the past four months, his delusions exacerbated and were accompanied by hallucinations of other modalities, like visual and kinesthetic hallucinations, which profoundly impacted his daily life. He used to hear voices. While listening to the voices, he also experienced voices coming out of his mouth. All these were experienced by him in clear consciousness daily for a few hours. All plausible medical causes of late-onset psychosis, such as neuroinflammatory/immunological disorders, were ruled out. Neuroimaging revealed T2-weighted image (T2WI)/fluid-attenuated inversion recovery (FLAIR) hyperintensity in bilateral subcortical and periventricular deep white matter, suggestive of small vessel ischemic changes in the brain. The diagnosis of VLOSLP is completely rationalized by evidence-based medicine. Hence, the role of cerebrovascular risk factors, as well as age-related neurobiological processes, in the pathogenesis of VLOSLP is discussed. Future research ought to emphasize identifying a particular biomarker that would be highly predictive for accurately diagnosing VLOSLP and giving it an identity to separate it from various overlapping clinical conditions such as dementia with Lewy bodies (DLB) and other types of dementia with psychosis so that the patient can be given specific treatment.