Nasal mucosa: a new site for tissue biopsy to diagnose hereditary TTR amyloidosis.

BACKGROUND AND OBJECTIVE We report 2 carriers of the TTRV30M mutation and its plasmatic biochemical marker with clinical symptoms compatible with hereditary TTR amyloidosis. MATERIALS AND METHODS Based on our previously reported casual finding of amyloid TTR in nasal mucosa (2008), we requested biopsy of this tissue to search for amyloid with Congo red staining and TTR immunohistochemical analysis. RESULTS The histological diagnosis was achieved by retrospective analysis of surgical sinonasal biopsy in the first patient and prospective biopsy of inferior nasal concha in the second. Large interstitial deposits of ATTR were observed in both cases. CONCLUSIONS We suggest nasal mucosa as a suitable site for tissue biopsy in patients with suspected hereditary TTR amyloidosis.