Cardiac 123I-MIBG uptake in de novo Brazilian patients with Parkinson's disease without clinically defined dysautonomia

Abstract

Myocardial scintigraphy with meta-iodo-benzyl-guanidine (123I cMIBG) has been studied in Parkinson's disease (PD), especially in Asian countries, but not in Latin America. Most of these studies include individuals with PD associated to a defined dysautonomia. Our goal is to report the cardiac sympathetic neurotransmission in de novo Brazilian patients with sporadic PD, without clinically defined dysautonomia. We evaluated retrospectively a series of 21 consecutive cases with PD without symptoms or signs of dysautonomia assessed by the standard bedside tests. This number was reduced to 14 with the application of exclusion criteria. 123I cMIBG SPECT up-take was low or absent in all of them and the heart/mediastinum ratio was low in 12 of 14. We concluded that 123I cMIBG has been able to identify cardiac sympathetic neurotransmission disorder in Brazilian de novo PD patients without clinically defined dysautonomia.

Orthostatic hypotension and cognitive impairment in Parkinson's disease: Causation or association?

“…Several studies have shown that H/M ratios are significantly reduced in PD when compared with controls, even in de novo disease. [38][39][40][41][42][43] Neuropathological studies have also confirmed the loss of postganglion sympathetic nerves in patients with PD. [44][45][46] The relationship between cardiac sympathetic denervation and OH in PD is complex.…”

“…). Several studies have shown that H/M ratios are significantly reduced in PD when compared with controls, even in de novo disease . Neuropathological studies have also confirmed the loss of postganglion sympathetic nerves in patients with PD …”

Diagnóstico e manejo da demência da doença de Parkinson e demência com corpos de Lewy: recomendações do Departamento Científico de Neurologia Cognitiva e do Envelhecimento da Academia Brasileira de Neurologia

“…A cintilografia meta-iodo-benzilguanidina ( 123 I-MIBG) consiste em um método de neuroimagem funcional molecular que demonstra denervação simpática miocárdica pós-ganglionar in vivo, e, quando esta é documentada, com base nos atuais critérios da MDS, é considerada um critério de suporte para o diagnóstico de DP, devido à alta especificidade >80% para o diagnóstico 21 . Um estudo prévio de Leite et al identificou denervação miocárdica simpática cardíaca pós-ganglionar em pacientes brasileiros com DP de novo sem disautonomia definida clinicamente 50 . Da mesma forma, a cintilografia com 123 I-MIBG também é classificada como um biomarcador indicativo nos atuais critérios de DCL, demonstrando boa sensibilidade (69%) e especificidade (87%) para discriminar DCL de DA 51 .…”

Diagnosis and management of Parkinson’s disease dementia and dementia with Lewy bodies: recommendations of the Scientific Department of Cognitive Neurology and Aging of the Brazilian Academy of Neurology

“…123 I-MIBG scintigraphy documenting cardiac sympathetic denervation is a supportive criterion for PD diagnosis, having over 80% specificity to distinguish PD from other parkinsonian conditions 21 . A study by Leite et al showed that this method identified cardiac sympathetic neurotransmission impairment in Brazilian de novo PD patients without clinically defined dysautonomia 50 . The DLB consortium criteria also classifies 123 I-MIBG as an indicative biomarker, showing good sensitivity (69%) and specificity (87%) values for discriminating probable DLB from probable AD 51 .…”