{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T11:57:32Z","timestamp":1780401452903,"version":"3.54.1"},"reference-count":45,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,5,14]],"date-time":"2025-05-14T00:00:00Z","timestamp":1747180800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Children"],"abstract":"<jats:p>Background: Seasonal influenza viruses are primarily known for causing respiratory illness, but rare hematologic complications can occur, especially in young children. While influenza A is more commonly linked to severe manifestations, influenza B can similarly precipitate life-threatening cytopenias, particularly in toddlers. Case Presentation: We report the case of a previously healthy 1-year-and-8-months-old girl who presented with a high fever, cough, and marked pallor during peak influenza season. Laboratory tests revealed significant microcytic, hypochromic anemia and severe thrombocytopenia. Rapid antigen testing was positive for influenza B. An extensive workup for other causes of bicytopenia, including leukemia, hemolysis, aplastic anemia, and other viral infections, yielded negative results. The child was managed with urgent red blood cell and platelet transfusions, oseltamivir antiviral therapy, broad-spectrum antibiotics, corticosteroids, and supportive care. Bone marrow aspiration was deferred in light of the rapid hematologic recovery. Her hemoglobin greatly improved, and her platelet count reached normal values at discharge. Conclusions: Our case underscores the need to consider influenza in the differential diagnosis of unexplained cytopenias during flu season. This case illustrates that influenza B can mimic hematologic malignancies. Rapid diagnosis and supportive treatment are essential to avoid fatal outcomes. Influenza vaccination plays a significant role in preventing severe complications, such as those we encountered.<\/jats:p>","DOI":"10.3390\/children12050632","type":"journal-article","created":{"date-parts":[[2025,5,14]],"date-time":"2025-05-14T10:27:41Z","timestamp":1747218461000},"page":"632","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Life-Threatening Anemia and Thrombocytopenia in a Toddler with Influenza B: Case Report and Literature Review"],"prefix":"10.3390","volume":"12","author":[{"given":"Irina","family":"Profir","sequence":"first","affiliation":[{"name":"Clinical Medical Department, Faculty of Medicine and Pharmacy, \u201cDun\u0103rea de Jos\u201d University of Gala\u021bi, 800216 Gala\u021bi, Romania"},{"name":"Clinical Emergency Children\u2019s Hospital \u201cSf. Ioan\u201d, 800487 Gala\u021bi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-9079-2831","authenticated-orcid":false,"given":"Cristina-Mihaela","family":"Popescu","sequence":"additional","affiliation":[{"name":"Clinical Emergency Children\u2019s Hospital \u201cSf. Ioan\u201d, 800487 Gala\u021bi, Romania"},{"name":"Dental-Medicine Department, Faculty of Medicine and Pharmacy, \u201cDun\u0103rea de Jos\u201d University of Gala\u021bi, 800201 Gala\u021bi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Iuliana","family":"Moraru","sequence":"additional","affiliation":[{"name":"Clinical Medical Department, Faculty of Medicine and Pharmacy, \u201cDun\u0103rea de Jos\u201d University of Gala\u021bi, 800216 Gala\u021bi, Romania"},{"name":"Clinical Emergency Children\u2019s Hospital \u201cSf. Ioan\u201d, 800487 Gala\u021bi, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e1012","DOI":"10.1093\/cid\/ciac734","article-title":"The Spectrum of Influenza in Children","volume":"76","author":"Hoy","year":"2023","journal-title":"Clin. Infect. Dis."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"605","DOI":"10.1542\/pir.2023-005962","article-title":"Influenza in Children and Adolescents: Epidemiology, Management, and Prevention","volume":"44","author":"Wolf","year":"2023","journal-title":"Pediatr. Rev."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"489","DOI":"10.1097\/INF.0000000000002610","article-title":"Comparative Severity of Influenza A and B Infections in Hospitalized Children","volume":"39","author":"Mattila","year":"2020","journal-title":"Pediatr. Infect. Dis. 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