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Introduction: Hereditary transthyretin (ATTRv) amyloidosis caused by the V30M (p. V50M) mutation is a fatal, neuropathic systemic amyloidosis. Liver transplantation has prolonged the survival of patients and central nervous system (CNS) complications, attributed to amyloid angiopathy caused by CNS synthesis of variant transthyretin, have emerged. The study aimed to ascertain amyloid deposition within the brain in long-term ATTRv amyloidosis survivors with neurological symptoms from the CNS.

Methods: A total of 20 patients with ATTR V30M having symptoms from the CNS and a median disease duration of 16 years (8–25 years) were included in this study. The cognitive and peripheral nervous functions were determined for 18 patients cross-sectionally at the time of the investigation. Amyloid brain deposits were examined by [18F]flutemetamol PET/CT. Five patients with Alzheimer's disease (AD) served as positive controls.

Result: 60% of the patients with ATTRv had a pathological Z-score in the cerebellum, compared to only 20% in the patients with AD. 75% of the patients with transient focal neurological episodes (TFNEs) displayed a pathological uptake only in the cerebellum. Increased cerebellar uptake was related to an early age of onset of the ATTRv disease. 55% of the patients with ATTRv had a pathological Z-score in the global cerebral region compared to 100% of the patients with AD.

Conclusion: Amyloid deposition within the brain after long-standing ATTRv amyloidosis is common, especially in the cerebellum. A cerebellar amyloid uptake profile seems to be related to TFNE symptoms.

Background and aims: Hereditary transthyretin amyloid (ATTRv) amyloidosis caused by the transthyretin (TTR) Val30Met (p.V50M) mutation is characterised by peripheral neuropathy, and central nervous (CNS) complications has rarely been reported. However, liver transplantation has prolonged the patients’ survival, and CNS complications attributed to amyloid angiopathy caused by CNS synthesis of variant TTR have been reported. The aim of the study was to ascertain CNS amyloid deposition in long-term ATTRv survivors.

Methods: 20 ATTR Val30Met patients with symptoms from the CNS and a median disease duration of 16 years (9-25 years) together with five Alzheimer (AD) patients, who served as positive controls were included in the study. Amyloid CNS deposits were assessed by 18F- flutemetamol PET/CT examination utilising relative z scores with pons as reference.

Results: Expectedly, all Alzheimer patients had an clearly increased global composite z score above 2.0 compared with 55% of the ATTRv patients. There was an increased local uptake corresponding to cerebellum in 12 ATTRv patients compared to only one in the AD group (fig 1). Four of these ATTRv patients had a global composite z score within the normal range. No correlation between duration after 9 years and amyloid CNS deposition was noted.

Conclusion: Amyloid deposition within the brain after long-standing ATTRv amyloidosis is increased and is often noted in the cerebellum. However, not all patient display amyloid CNS deposition, thus, additional causes for CNS complications should always be considered.