Sporadic behavioral phenotype of Right Temporal Variant of Frontotemporal Dementia: a case report

Abstract

AbstractBackgroundThere are two subtypes of the right Temporal Variant of Frontotemporal Dementia (rtv‐FTD). Semantic dementia (SMD) phenotype is defined by negative familiar history, word‐finding, anomia, comprehension difficulties, prosopagnosia, and topographagnosia. The behavioral frontotemporal dementia (bvFTD) phenotype is defined by personality changes, inappropriate behaviors, positive family history, and relatively poor performance on neurobehavioral testing with better performance on confrontational naming tests. (1) We present a rare interesting case.MethodWe describe the clinical and imaging features of a man who presented a sporadic behavioral phenotype of rtv‐FTD, showing negative genetic results.ResultA 62‐year‐old man with 8 years of progressive behavioral impairment. He showed personality changes, and compulsive‐like / ritualistic behaviors such as excessive unpurposed accumulation of items, washing hands repeatedly every five minutes, and walking and wandering repeatedly in circles. He also had hiperorality, cravings for sweet foods, social cognition impairment, associated with loss of empathy, and inappropriate social behavior (hypersexuality, verbal aggressivity to unrelated people, and talking bad words to neighbors with no reason). After years he followed with mild to moderate apathy. The neuropsychological evaluation showed impairment of executive functioning, episodic memory impairment, and MMSE 19/30. The neurological exam was unremarkable, and the familiar history was negative. Brain MRI revealed frontotemporal atrophy with a marked asymmetry in the right temporal lobe. The genetic testing was negative, illustrating and sporadic case.ConclusionTheoretically, rtv‐FTD is considered a right variant of semantic phenotype, and the general assumption is that is also a sporadic disorder. Although the behavioral phenotype of rtv‐FTD normally has a genetic basis, showing positive family history, It can be presented as a sporadic disorder with non‐familial variants of FTD, as in this case. (2)