Dados do Trabalho

Título

Demyelinating neurophysiological findings in family amyloid polyneuropathy

RESUMO

Case presentation: A 69-year-old man presented with paraesthesias, significant weight loss, fasciculations and proximal and distal weakness in the four limbs. His clinical picture had begun less than a year ago. Physical examination of the patient showed diffuse arreflexia, thermoalgic hypoesthesia with dependent length pattern and flaccid tetraparesis. There was no cranial nerve dysfunction. Electroneuromyography showed polyradiculoneuropathy with mixed axonal/demyelinating pattern that met criteria for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Cerebral spinal fluid did not show significant albuminocytological dissociation. The patient underwent intravenous corticosteroid therapy with methylprednisolone, without satisfactory clinical response. He was then submitted to a genetic panel of neuromuscular diseases, which identified the Ile127Val mutation, known to be pathogenic for transthyretin family amyloid polyneuropathy (TTR-FAP).
Discussão: Although the typical neurophysiological finding of TTR-FAP is axonal sensory-motor polyneuropathy, it is common to observe heterogeneous patterns of presentation in electroneuromyography. There are reports in the literature of clinical and nerurophysiological presentations that mimic CIDP. Demyelination findings are probably secondary to axonal degeneration.
Final Comments: The variability of TTR-FAP manifestations may delay it's diagnosis, which may directly compromise the indication of treatment for these patients. In these cases, knowledge about the neurophysiological findings of FAP can be used as an auxiliary tool in the differential diagnosis.