A Rare Cause of Cytopenias in Childhood: Paroxysmal Nocturnal Hemoglobinuria

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare hematopoietic stem cell disorder characterized by hemolysis, thrombosis and impaired bone marrow functions. PNH is rarely seen in childhood and usually presents with hypoplastic/aplastic anemia clinic. If the major clinical finding is hemolysis, eculizumab (monoclonal anti-C5 immunoglobulin) can be used for treatment. The other treatment options for PNH are immunosuppressive therapy and stem cell transplantation (SCT). Fluorescent aerolysin (FLAER)-based assay is a high sensitivity test for PNH diagnosis in children. FLAER has become the gold standard for the diagnosis and follow-up of PNH get today. Res Pediatr Neonatol Copyright © Baris Yilmaz 229 How to cite this article: Baris Y. A Rare Cause of Cytopenias in Childhood: Paroxysmal Nocturnal Hemoglobinuria. Res Pediatr Neonatol. 3(2). RPN.000559.2019. DOI: 10.31031/RPN.2019.03.000559 Volume 3 Issue 2 found in radiological examinations. During the follow-up period, the patient had developed diarrhea and microscopic examination of feces contained no leukocytes and no pathological agents. In feces, Clostridium difficile toxins A and B, Adenovirus, Rotavirus, Giardia and Entamoeba histolytica antigens were screened and resulted to be negative. In blood serological tests, Anti Hbs and Anti CMV IgG were positive and all other serological tests were negative. Parvovirus IgM and IgG and Anti HIV1 / 2 + p24 Ag were negative. During the follow-up period, the patient had significant clinical improvement and blood, CSF, urine cultures remained to be negative (no growth is seen), therefore patient was discharged, and a polyclinic follow-up was scheduled for her. One week later, she was diagnosed with acute leukemia, aplastic anemia, hypoplastic myelodysplastic syndrome (MDS) though bone marrow aspiration and biopsy. Microscopic examination of bone marrow aspiration with Giemsa staining revealed severe hypocellular bone marrow, which consisted of cells those exhibit uninterrupted maturation. Bone marrow contained each series of cells but displayed predominantly decreased myeloid series (Myeloid / Erythroid series ratio: 1/3). There were dysmorphic changes in the erythroid series. Plastic cell ratio was <1%. Immunophenotypic analysis of bone marrow aspiration material by flow cytometry revealed lymphocytes in 45% and non-lymphocyte mononuclear cells in 4%. Lymphocytes were predominantly composed of T lymphocytes (29%). 2% of the total cells were monocytes and 2% of all cells were myeloid progenitor cells. In the biopsy report from the pathology, it was learned that the cell / fat ratio was 15/85, there were no ring side oblasts, the dyeable iron level was <1+ and the patient was diagnosed with aplastic anemia. For the differential diagnosis of aplastic anemia, DEB test was performed and resulted as negative, MDS panel (monosomy 5 and 7, trisomy 5 and 8, 5q-, 7q-) resulted as negative; patient’s karyotype was found to be 46XX as expected. By using flow cytometry CD59 expression in erythrocytes, by using FLAER evaluation of macrocytes and granulocytes have been evaluated: PNH clone have been detected in our patient (Table 1). Table 1: PNH-Clones at diagnosis time.