Dados do Trabalho

Título

Early diagnosis of hereditary amyloidosis

RESUMO

Case presentation: Asymptomatic individuals carrying the hereditary amyloidosis gene are screened and submitted to annual assessments in our service and it include a neurological examination, a questionnaire on symptoms of dysautonomia, complementary tests that include electroneuromyography and screening for dysautonomia, such as Quantative Sensory Test(QST), heart rate variability HRV) and reflex sympathetic response (RSR).
We identified abnormal findings in two young women carriers of the hereditary amyloidosis transthyretin.
A 32-year-old female carrier of Phe84Leu gene presented symptoms of dysautonomia (blurred vision, dry eyes, increased sweating in her hands, orthostatic intolerance and constipation). The electroneuromyography showed mild carpal tunnel syndrome bilateral. The reflex-sympathetic response was abolished in the four limbs. She was then submitted to a salivary gland biopsy which revealed deposit of amyloid material. Her father was the index case and at the age of 64 he started a condition of polyneuropathy and dysautonomia, receiving a late diagnosis and treatment was not possible, dying from disease complications. The second case was a 22-year-old female carrier of Val50met gene. She had reflex sympathetic response abolished in the 4 segments and the quantative sensory test (QST), revealed warm detection and warm pain thresholds were higher and the cold detection and cold pain thresholds were smaller when compared to a sex and age matched healthy control. She also underwent salivary gland biopsy, which also confirmed the deposition of amyloid material in the tissue. Her aunt was the index case and presented polyneuropathy and dysautonomia at the age of 38, and treatment was not possible because it was in an advanced stage.
Discussion: Hereditary amyloidosis transthyretin is a rare, autosomal dominant systemic disease caused by extracellular deposition of insoluble amyloid fibrils formed by the mutated transthyretin protein. The clinical presentation and the age of onset varies. The disease is often rapidly progressive, so an early diagnosis is important for a an effectively treatment.
Final comments :Systematic and regular monitoring of an asymptomatic carrier is necessary to detect early signs of hereditary amyloidosis transthyretin.