Objective:

To illustrate the diagnostic challenges and atypical clinical features of late-onset hereditary transthyretin amyloidosis (ATTRv) in a patient with a specific TTR gene mutation.

Approach:

• Patient Presentation: A 59-year-old man presented with distal numbness, weakness, hoarseness, and cough over two years, consulting multiple specialists without a definitive diagnosis.
• Diagnostic Investigations: Electrocardiography and echocardiography were performed, followed by 99mTc-pyrophosphate scintigraphy and genetic testing to confirm the diagnosis.

Key Findings:

• The patient had a c.349G > T (p.Ala117Ser) mutation in the TTR gene.
• Atypical symptoms such as hoarseness and cough were significant in the diagnostic process.
• Cardiac imaging and genetic screening were crucial in confirming the diagnosis of ATTRv.
• The case illustrates that atypical symptoms may serve as important clues to ATTRv in middle-aged and older patients.

Interpretation:

This case illustrates the diagnostic challenges of hereditary transthyretin amyloidosis, particularly the importance of recognizing atypical symptoms in the diagnostic process.

Limitations:

• The case is based on a single patient, which limits the generalizability of the findings.
• There may be potential biases in the diagnostic process due to multiple consultations with various specialists.

Conclusion:

Prompt integration of cardiac imaging and genetic screening can help avoid diagnostic delays in cases of late-onset ATTRv.