Schizophrenia or Neurodegenerative Disease Prodrome? Outcome of a First Psychotic Episode in a 35-Year-Old Woman

Abstract

Background Patients with early onset neurodegenerative disease can present with a clinical syndrome that overlaps with schizophrenia, and it is not uncommon for these patients to undergo long-term care in psychiatric settings rather than receiving more appropriate care by neurologists specializing in their disease. Case report A 35-year old woman who presented with new-onset delusions, eating abnormalities, disorganized behavior, lack of insight, disinhibition, and stereotypical motor behaviors was diagnosed with schizophrenia and institutionalized. Later she was found to have a MAPT tau S356T mutation and a focal pattern of brain atrophy consistent with frontotemporal dementia (FTD). Conclusion Physicians should be aware of the potential overlap in symptoms and age of onset between some forms of FTD and schizophrenia, and should include FTD in the diagnostic differential for adult patients with new onset, rapidly progressive personality changes or behavioral symptoms such as binge eating, high levels of social disinhibition, or progressive mutism.

Psychosis in behavioral variant frontotemporal dementia

“…It is noteworthy that bvFTD patients in the present study tend to have a lower total score at the positive subscale of the PANSS than that found in studies on schizophrenia (9.5 in bvFTD patients in the present study versus 18.2 in schizophrenia patients) 20. This suggests that these positive psychotic symptoms are not the most prominent symptoms in the clinical overlap of bvFTD and psychotic disorders.…”

“…Previous studies on psychotic symptoms in bvFTD were focused only on positive psychotic symptoms (eg, hallucinations, delusions, and paranoia) and found that these psychotic features were present in 10%–32% of bvFTD patients 3,15–17. Even though negative psychotic symptoms and formal thought disorders have led to frequent misdiagnosis of psychosis in bvFTD patients, comprehensive studies on the full spectrum of psychosis in bvFTD are lacking 5,8,18–20. Although the distinction between bvFTD and psychiatric disorders is a major diagnostic dilemma, especially in the early stages of disease,3,5,21 knowledge on psychotic symptoms in bvFTD based on this common broad definition of psychosis cannot be ignored.…”

Psychotic Symptoms in Frontotemporal Dementia

“…The hyperorality observed in FTD, particularly for sweets, is also noted to be uncommon in schizophrenia [26,37]. Neuroimaging features may also aid in the diagnosis, as the frontotemporal atrophy and hypoperfusion/hypometabolism of bvFTD are typically more extreme that that observed in schizophrenia (Fig.…”

“…There are fewer details on the nature of psychotic symptoms in MAPT carriers. One case report describes a bizzare delusion in a 35-year-old patient with FTD who claimed she was a park ranger who saved a girl from a rattle snake by picking it up and kissing it [26].…”

“…BIf they are clearly implausible and not understandable to same-culture peers and do not derive from ordinary life experiences^ [60] Claimed she was a park ranger who saved a girl from a rattle snake by picking it up and kissing it [26] Fregoli's delusion BMistaken belief that some person currently present in the deluded person's environment (typically a stranger) is a familiar person in disguise [ 63] Recognizing strangers as acquaintance, despite lack of any resemblance [59] Hallucinations BPerception-like experiences that occur without an external stimulus…They may occur in any sensory modality^ [60] Visual hallucinations of faces or partial faces talking to patient [11]; Satan voice ordering to harm daughter [8]; pruritus caused by infects and snakes on skin [8] predates knowledge of the C9ORF72 mutation. In our experience, early in the symptom course, patients with DLB may have good insight into the hallucinatory nature of these experiences and do not converse with hallucinatory images of people, or may simply tell them to go away, while some of our patients with FTD have been amused at the visual hallucinations of faces and described carrying on pleasant two-way conversations with the images [11].…”