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This is the first report of concurrent thrombotic complications in the setting of AL-amyloid-induced FX deficiency. We discuss the diagnostic and therapeutic conundrum of diagnosing AL amyloidosis with bruising as the leading clinical symptom and the management of acute deep vein thrombosis in the setting of FX deficiency.<\/jats:p>","DOI":"10.1136\/bcr-2024-260169","type":"journal-article","created":{"date-parts":[[2024,6,5]],"date-time":"2024-06-05T21:42:23Z","timestamp":1717623743000},"page":"e260169","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":1,"title":["Acute deep vein thrombosis with concurrent new diagnosis of AL-amyloid-induced factor X deficiency"],"prefix":"10.1136","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0603-1196","authenticated-orcid":false,"given":"Emily Lauren","family":"Paton","sequence":"first","affiliation":[{"name":"Department of Medicine, Oregon Health & Science University, Portland, Oregon, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4273-2907","authenticated-orcid":false,"given":"Stefan","family":"Barisic","sequence":"additional","affiliation":[{"name":"Department of Medicine, Oregon Health & Science University, Portland, Oregon, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jean Michael","family":"Sabile","sequence":"additional","affiliation":[{"name":"Department of Medicine, Division of Hematology & Medical Oncology, Oregon Health & Science University Knight Cancer Institute, Portland, Oregon, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eva","family":"Medvedova","sequence":"additional","affiliation":[{"name":"Department of Medicine, Division of Hematology & Medical Oncology, Oregon Health & Science University Knight Cancer Institute, Portland, Oregon, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"239","published-online":{"date-parts":[[2024,6,5]]},"reference":[{"key":"2025082623332173000_17.6.e260169.1","doi-asserted-by":"crossref","unstructured":"Perry DJ . 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