{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,6]],"date-time":"2026-05-06T02:26:35Z","timestamp":1778034395218,"version":"3.51.4"},"reference-count":38,"publisher":"BMJ","issue":"1","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Case Rep"],"accepted":{"date-parts":[[2023,1,11]]},"published-print":{"date-parts":[[2023,1]]},"abstract":"<jats:p>Classically, deficiencies of vitamin B<jats:sub>12<\/jats:sub> and folate are associated with megaloblastic anaemia. Additionally, vitamin B<jats:sub>12<\/jats:sub> is able to cause a haemolytic anaemia in the form of pseudo-thrombotic microangiopathy (pseudo-TMA). Here, we present a case of a middle-aged woman with a history of Roux-en-Y gastric bypass who presented with dyspnoea and fatigue and was found to have thrombocytopenia and a non-immune haemolytic anaemia. Work-up for haemolytic uraemic syndrome, thrombotic thrombocytopenic purpura, paroxysmal nocturnal haemoglobinuria, infection, malignancy and autoimmune conditions was unremarkable. Her haemolytic anaemia and thrombocytopenia resolved with folate replenishment. She was diagnosed as likely having pseudo-TMA secondary to folate deficiency.<\/jats:p>","DOI":"10.1136\/bcr-2022-251473","type":"journal-article","created":{"date-parts":[[2023,1,20]],"date-time":"2023-01-20T11:36:42Z","timestamp":1674214602000},"page":"e251473","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":5,"title":["Pseudo-thrombotic microangiopathy due to folate deficiency"],"prefix":"10.1136","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1811-3890","authenticated-orcid":false,"given":"Emily","family":"Larkin","sequence":"first","affiliation":[{"name":"Internal Medicine, University of Virginia School of Medicine, Charlottesville, Virginia, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Samuel","family":"Konkol","sequence":"additional","affiliation":[{"name":"Internal Medicine, University of Virginia Health System, Charlottesville, Virginia, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Meghan","family":"Geraghty","sequence":"additional","affiliation":[{"name":"Internal Medicine, University of Virginia Health System, Charlottesville, Virginia, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"239","published-online":{"date-parts":[[2023,1,20]]},"reference":[{"key":"2025082712272146000_16.1.e251473.1","doi-asserted-by":"publisher","DOI":"10.1111\/bjh.12959"},{"key":"2025082712272146000_16.1.e251473.2","doi-asserted-by":"publisher","DOI":"10.3945\/jn.114.206599"},{"key":"2025082712272146000_16.1.e251473.3","doi-asserted-by":"crossref","DOI":"10.1186\/s12878-015-0036-2","article-title":"Therapeutic dilemma in the management of a patient with the clinical picture of TTP and severe B12 deficiency","volume":"15","author":"Walter","year":"2015","journal-title":"BMC 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