{(Talasemia-β di Penderita Pengidap Leukemia Limfoblastik Akut (LLA)}

Thalassemias are a heterogeneous group of genetic disorders. β-thalassemia is due to impaired production of beta globin chains, which leads to a relative excess of alpha globin chains. The abnormalities of hemoglobin synthesis are usually inherited but may also arise as a secondary manifestation of another disease, most commonly hematological neoplasm. In this article, two cases of acquired β-thalassemia in children with ALL focusing on the diagnosis and the possible relationship between the two hematological diseases are presented. The first case was a four (4) year old boy with ALL-L1 type at the maintenance phase of chemotherapy, suffering from anemia with Hb 8.0 g/dL, WBC 22.600/mm3 and  platelet count of 200.000/mm3, peripheral blood smear revealed anisocytosis, polychromasia, hypochromia, basophilic stippling, and normoblasts. The result of Hb electrophoresis was as follows,  Hb A 54.9 %, Hb F 29.4 %, Hb E  13.4 % and Hb A2 2.3 %. The patient was diagnosed as ALL-L1 type and β-Thalassemia. The second case, was a 13 year old girl with ALL-L1 type in remission after chemotherapy, she suffered from anemia with Hb 6.7 g/dL, WBC 12,400/mm3, platelet count  200,000/mm3, and peripheral blood smear showed anisocytosis, hypochromia, normoblasts, myelocytes and basophilic stippling. The results of Hb electrophoresis were  Hb F 0.41%, Hb A1c 0.78%, Hb A2 2.95% with the conclusion of a β-thalassemia trait, this patient was then diagnosed as  ALL-L1 type remission + β-thalassemia trait. The case reviewers assumed that the acquired β-thalassemia in these patients were due to the altered expression of globin chain. The mechanism of this syndrome might be the acquisition of α  mutation affecting RNA or proteins involved in α-globin gene regulation and resulting in the reduction of the (α/β)-globin biosynthetic ratios, or/and associated with chemotherapy-inducement.     Talasemia adalah kelompok kelainan genetik pembentukan hemoglobin. Di talasemia-β hasilan rantai β terhambat, sehingga menyebabkan rantai α meningkat. Kelainan pembentukan hemoglobin bersifat diturunkan, tetapi dapat muncul sebagai manifestasi sekunder dari beberapa penyakit, pada umumnya berupa keganasan hematologis. Tujuan laporan dua kasus talasemia-β di penderita LLA ini, menitikberatkan hal terkait tata diagnosis dan kemungkinan hubungan kedua kelainan hematologis tersebut. Kasus pertama ialah seorang anak laki-laki berusia 4 tahun dengan LLA-L1 sedang menjalani kemoterapi tingkat rumatan, penderita mengalami anemia dengan Hb 8,0 g/dL, WBC 22.600/mm3, platelet 200.000/mm3, hapusan darah tepi didapatkan anisositosis, polikromasia, hipokromia, basophilic stippling, normoblast. Hasil Hb electrophoresis Hb A 54,9 %, Hb F 29,4 %, Hb E 13,4 % dan Hb A2 2,3 %. Penderita didiagnosis LLA-L1 dan talasemia-β. Kasus kedua, anak perempuan berusia 13 tahun dengan LLA-L1 remisi pasca kemoterapi, penderita mengalami anemia dengan Hb 6,7 g/dL, WBC 12.400/mm3, platelet 200.000/mm3, hapusan darah tepi didapatkan anisositosis, hipokromia, normoblast, mielosit, basophilic stippling. Hasil Hb elektrophoresis Hb F 0,41%, Hb A1c 0,78%, Hb A2 2,95%. Penderita didiagnosis LLA-L1 remisi dan talasemia-β trait. Dalam kasus ini dapat didugakan bahwa talasemia-β di penderita LLA terjadi karena perubahan ekspresi rantai globin dengan mekanisme perpindahan RNA atau pengaturan gen globin yang menyebabkan berkurangnya angka banding biosintesis (α/β)-globin, atau dan dihubungkan dengan dipicu kemoterapi yang diberikan.