{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T23:16:38Z","timestamp":1790982998216,"version":"4.1.0"},"reference-count":22,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T00:00:00Z","timestamp":1785283200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Med."],"abstract":"<jats:p>Heparin-induced thrombocytopenia (HIT) type 2 is a major complication of heparin therapy and associated with considerable morbidity and mortality. Correct diagnosis, especially in the intensive care setting where thrombocytopenia occurs frequently, is of paramount importance. We report a 44-year-old female patient undergoing surgical replacement of the tricuspid valve due to Ebstein anomaly. Peri-operatively, the patient was treated with unfractionated heparin (UFH). Sixteen days after treatment initiation, computed tomography incidentally revealed multiple splenic infarctions consistent with embolic infarction. The 4T score was 3 points, suggesting a low pre-test probability for HIT; however, its applicability was limited by post-cardiac surgery platelet kinetics and the absence of a typical platelet fall. A PF4\/heparin antibody immunoassay was therefore performed and showed strong positivity (optical density 2.07, lower limit of normal &amp;lt;0.51). Anticoagulation was changed to argatroban, followed by apixaban. Importantly, although an initial perioperative platelet decline of 59% was observed consistent with cardiopulmonary bypass-related consumption, platelet counts had recovered to within the normal range at the time of diagnosis, and no classical secondary platelet fall was observed. In summary, we report a case of possible HIT in which platelet count-based risk stratification may not have fully captured an atypical presentation in this selected clinical setting.<\/jats:p>","DOI":"10.3389\/fmed.2026.1867949","type":"journal-article","created":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T05:58:10Z","timestamp":1785304690000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Possible atypical heparin-induced thrombocytopenia presenting with splenic infarction despite preserved platelet counts after cardiac surgery \u2013 a case report"],"prefix":"10.3389","volume":"13","author":[{"given":"Thomas M.","family":"Hofbauer","sequence":"first","affiliation":[{"name":"Department of Cardiology, Internal Medicine II, Medical University of Vienna","place":["Vienna, 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