Global patterns of amyloid typing: results of a survey by the International Society of Amyloidosis (ISA)
Hironobu Naiki, Mona Johnson, Kaylee Walters, Alexander Carpinteiro, M. Teresa Cibeira, Anita D’Souza, Efstathios Kastritis, Mathew S. Maurer, Lisa Mendelson, Giampaolo Merlini, Eli Muchtar, Giovanni Palladini, Eloísa Riva, Yoshiki Sekijima, Per Westermark, Shaji Kumar, Stefan Schönland
Abstract
Background Accurate tissue typing in amyloidosis is essential to provide appropriate therapy for individual patients.Objective To get a real-life overview of typing strategies worldwide.Methods The International Society of Amyloidosis (ISA) performed an online questionnaire survey among ISA members. We prepared questionnaire sheets for referral institutions (Category 1; C1), institutions performing amyloid typing for internal requests only (C2), and institutions outsourcing amyloid typing to referral institutions (C3), respectively.Results Seventy-six institutions participated in this survey, including C1 (n = 33), C2 (n = 20) and C3 (n = 23) institutions. Multiple typing methods were available across the responding institutions, including immunohistochemistry (85% of C1/C2 institutions), immunofluorescence microscopy (43%), genetic analysis (77%) and mass spectrometric analysis (42%). Commercial antibodies were used worldwide for immunohistochemistry. C1 institutions in Europe and Asia also used various in-house antibodies. Ninety-three percent of institutions performed genetic analysis of TTR gene, followed by APOA1 (43%), FGA, GSN, LYZ (33%) and APOA2 (31%). Hierarchical referral flows of mass spectrometric analysis, immunohistochemistry and genetic analysis were observed regionally and internationally. Globalization and centralization of referral flows were more prominent for mass spectrometric analysis.Conclusion These data provide an assessment of the current state, enabling improvement in capabilities of amyloid typing worldwide and enhancing regional/international networks.