Combination of familial transthyretin amyloidosis and hyperlipoproteinemia(a) in a patient with spinal canal stenosis: a case report

Hereditary transthyretin amyloidosis is a rare, progressive, systemic autosomal dominant disorder characterized by the extracellular deposition of insoluble amyloid fibrils in the peripheral nervous system, heart, and other organs. Among the specific signs of this condition, symptomatic spinal canal stenosis is prominent. Lipoprotein(a) is an atherogenic lipoprotein, and increased plasma concentrations are a significant risk factor for cardiovascular and cerebrovascular diseases. Data regarding the relationship between transthyretin amyloidosis and lipoprotein(a) levels are limited.

This article presents a clinical case of a patient with arterial hypertension, with blood pressure elevated to 150/90 mmHg for 5 years. Following a COVID-19 infection between June 2, 2021, and June 25, 2021, the patient experienced a marked increase in blood pressure to 290/150 mmHg; sharp left-sided chest pain lasting 20–30 minutes unrelated to physical activity, which was relieved with medication; and pain in the cervical and thoracic spine. Despite antihypertensive therapy, the patient’s blood pressure stabilized at 110/70 mmHg. Further evaluation revealed dyslipidemia, with increased low-density lipoprotein cholesterol levels at 4.53 mmol/L and lipoprotein(a) at 1.46 g/L. Doppler ultrasound revealed atherosclerosis in the extracranial parts of the brachiocephalic arteries, with up to 20% stenosis of the right internal carotid artery. Echocardiography showed thickening of the left ventricular wall, interatrial septum, and mitral valve leaflets, although the ejection fraction remained preserved. Magnetic resonance imaging of the spine revealed cervical spinal canal stenosis (C5–C6). Genetic testing identified a nucleotide sequence variant in the transthyretin gene (Chr18: 29171879 G>A, p. Arg5His) in the heterozygous state in the patient and her blood relatives. Specific anti-amyloid therapy with tafamidis was considered, and hypolipidemic therapy was initiated.

In patients with symptomatic spinal canal stenosis and left ventricular wall thickening, even in the presence of hypertension, comprehensive evaluation is crucial for the timely diagnosis and adequate management of amyloid cardiomyopathy. Thus, we describe the first reported clinical case of the combination of familial transthyretin amyloidosis and hyperlipoproteinemia(a).