en Adults Hematology & Oncology Adults Hematology & Oncology <p style="text-align: justify;"><span style="font-size:14px;"><span style="font-family:Arial;"><strong>Background: </strong>Angioimmunoblastic T-cell lymphoma (AITL) is an uncommon lymphoma arising from follicular T-helper cells. Since this is a rare disease, diagnosis is unfortunately difficult. AITL responds to treatments, therefore by reviewing the characteristics of the available cases, we aimed to classify the available data for in-time diagnosis.<br> <strong>Objectives and data sources:</strong> A systematic search was performed on PubMed, Scopus, and Web of Science to January 5, 2023, to investigate the presence of peripheral blood lymphocytosis and leukocytosis in AITL cases.<br> <strong>Results:</strong> Among 129 papers, 41 articles with 46 cases were included. All 41 studies were checked in terms of quality by two independent reviewers using an eight-item Joanna Briggs Institute checklist for case report studies. We also reported a 57-year-old Iranian woman with AITL suspected rash. Complete blood count (CBC) analysis showed a significant lymphocytosis and leukocytosis of 26 and 37.5 &times; 109 /L, respectively.<br> <strong>Conclusion: </strong>In the reviewed cases, male predominance was obvious. Lymphadenopathy was the most seen clinical presentation. Dermal abnormalities were presented in more than half of the patients. The prevalence of blood eosinophilia was also remarkable; CD3 and CD4 were expressed the most and CD7, CD8, CD30, and CD56 the least. Despite treatment, the mortality rate was high. In this systematic review, we tried to provide a complete classified review of all AITL cases with different types of leukocytosis to avoid future miss diagnosis of this rare lymphoma.</span></span></p> Angioimmunoblastic T-cell lymphoma, Immunoblastic Lymphadenopathy, Leukocytosis, Lymphocytosis 36 52 http://ijbc.ir/browse.php?a_code=A-10-936-1&slc_lang=en&sid=1 Esmaeil Shahabi Satlsar esmaeilshahabi@yahoo.com 10031947532846008644 10031947532846008644 No Clinical laboratory sciences department, School of Paramedical Sciences, Guilan University of Medical Sciences, Rasht, Iran Saeid Anvari drsaeidanvari@gmail.com 10031947532846008645 10031947532846008645 No Regenerative medicine, organ procurement and transplantation multi-disciplinary center, Razi hospital, school of medicine, Guilan university of medical sciences, Rasht, Iran; drsaeidanvari@gmail.com Fatemeh Sotoudeh f.sotoudeh.2000@gmail.com 10031947532846008646 10031947532846008646 No Student research committee, school of paramedical sciences, Guilan university of medical sciences, Rasht, Iran Seyed Hossein Mirpour Hassankiadeh mirhossein07@yahoo.com 10031947532846008647 10031947532846008647 No Department of Internal Medicine, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran; Amirhossein Rastgar amirhosseinrastgar74@gmail.com 10031947532846008648 10031947532846008648 No Department of Hematology and Blood Banking, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran Setare Kheyrandish 7masterstar@gmail.com 10031947532846008649 10031947532846008649 Yes Department of Hematology and Blood Banking, School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran