Senile Systemic Amyloidosis Presenting as Hematuria: A Rare Presentation and Review of Literature

Thromboembolic and bleeding risk in cardiac amyloidosis

Cardiac amyloidosis represents a spectrum of conditions characterized by the accumulation of insoluble fibrils, resulting in progressive deposition and myocardial dysfunction. The exact mechanisms contributing to the heightened risk of thromboembolic events and bleeding tendencies in cardiac amyloidosis remain unclear. Proteins such as transthyretin in transthyretin amyloidosis and light chains in light-chain amyloidosis, along with acute phase proteins in amyloid A (AA) amyloidosis, play complex roles in the coagulation cascade, affecting both coagulation initiation and fibrinolysis regulation. The increased occurrence of atrial fibrillation, systolic and diastolic left ventricular dysfunction, and atrial myopathy in patients with cardiac amyloidosis may predispose them to thrombus formation. This predisposition can occur regardless of sinus rhythm status or even with proper anticoagulant management. Bleeding events are often linked to amyloid deposits around blood vessels, which may increase capillary fragility and cause coagulation disturbances, leading to unstable international normalized ratio levels during anticoagulant therapy. Thus, comprehensive risk assessment for both thrombotic and hemorrhagic complications, especially before commencing anticoagulant therapy, is imperative. This review will explore the essential pathophysiological, epidemiologic, and clinical aspects of thromboembolic and bleeding risk in cardiac amyloidosis, evaluating the existing evidence and uncertainties regarding thrombotic and bleeding risk assessment and antithrombotic treatment.

Thromboembolic and Bleeding Events in Transthyretin Amyloidosis and Coagulation System Abnormalities: A Review

Transthyretin amyloidosis (ATTR) is a group of diseases caused by the deposition of insoluble fibrils derived from misfolded transthyretin, which compromises the structure and function of various organs, including the heart. Thromboembolic events and increased bleeding risk are among the most important complications of ATTR, though the underlying mechanisms are not yet fully understood. Transthyretin plays a complex role in the coagulation cascade, contributing to the activation and regulation of the coagulation and fibrinolytic systems. The prevalence of atrial fibrillation, cardiac mechanical dysfunction, and atrial myopathy in patients with ATTR may contribute to thrombosis, though such events may also occur in patients with a normal sinus rhythm and rarely in properly anticoagulated patients. Haemorrhagic events are modest and mainly linked to perivascular amyloid deposits with consequent capillary fragility and coagulation anomalies, such as labile international-normalised ratio during anticoagulant therapy. Therefore, it is paramount to carefully stratify the thrombotic and haemorrhagic risks, especially when initiating anticoagulant therapy. Our review aims to ascertain the prevalence of thromboembolic and haemorrhagic events in ATTR and identify potential risk factors and predictors and their impact on antithrombotic therapy.

A Case of Isolated Renal Light Chain Amyloidosis With Hematuria and Low Complement Levels

The prevalence of light chain (AL) amyloidosis, characterized by the deposition of amyloid chains, is gradually increasing. The clinical features of the disease depend upon the location of amyloid deposition and can manifest in many forms. Although laboratory investigations can reveal proteinuria and change in complement levels, hematuria and low complement levels are rarely reported. There are very few cases of renal AL amyloidosis presenting as persistent hematuria. We present the case of a 54-year-old female presenting with abdominal pain, proteinuria, and moderate persistent hematuria on admission who was later diagnosed with AL amyloidosis on biopsy.

The discovery and development of transthyretin amyloidogenesis inhibitors: what are the lessons?

Transthyretin (TTR) is associated with several human amyloid diseases. Various kinetic stabilizers have been developed to inhibit the dissociation of TTR tetramer and the formation of amyloid fibrils. Most of them are bisaryl derivatives, natural flavonoids, crown ethers and carborans. In this review article, we focus on TTR tetramer stabilizers, genetic therapeutic approaches and fibril remodelers. The binding modes of typical bisaryl derivatives, natural flavonoids, crown ethers and carborans are discussed. Based on knowledge of the binding of thyroxine to TTR tetramer, many stabilizers have been screened to dock into the thyroxine binding sites, leading to TTR tetramer stabilization. Particularly, those stabilizers with unique binding profiles have shown great potential in developing the therapeutic management of TTR amyloidogenesis.

Gross hematuria: An unusual presenting symptom of systemic wild-type transthyretinamyloidosis

Amyloidosis of the urinary bladder is a rare cause of gross hematuria. In patients with systemic amyloidosis, identification is nearly always related to cardiac complaints; urologic presenting symptoms are extremely uncommon. We present a 77-year-old male patient with painless gross hematuria ultimately found to be secondary to systemic wild-type transthyretin amyloidosis. He underwent transurethral resection of the bladder lesion and was initiated on transthyretin stabilizing medication. In the 6 months since starting treatment, the patient has had no further episodes of gross hematuria, but will require cystoscopic surveillance for evidence of recurrence or concomittment urothelial carcinoma.

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Systemic transthyretin amyloidosis diagnosed after an episode of painless gross hematuria.

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Extremely uncommon presenting symptom; only the second documented patient.

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No evidence of recurrent disease at 6 months status post transurethral resection.