Tehran University of Medical Sciences Case Reports in Clinical Practice 2538-2683 10 6 2026 06 03 247 252 Babak Nejati Hematology and Oncology Research Center, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran. Shalaleh Aghaei Hematology and Oncology Research Center, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran. Gholamreza Ravaei Hematology and Oncology Research Center, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran. 2025 12 28 2026 04 26 Myeloperoxidase (MPO) deficiency is a rare genetic disorder affecting neutrophil and monocyte function. It can present with diverse clinical manifestations, from recurrent infections to unexplained systemic symptoms. Here, we present two cases of MPO deficiency with distinct presentations: a 47-year-old female with recurrent pneumonia and a 25-year-old male with pruritus. Both patients were found to have neutropenia, leading to further hematologic evaluation and confirmation of MPO deficiency. This report highlights the variability in clinical manifestations and underscores the importance of considering MPO deficiency in patients with unexplained neutropenia.  https://crcp.tums.ac.ir/index.php/crcp/article/view/1160 https://crcp.tums.ac.ir/index.php/crcp/article/download/1160/757