Case history
The patient was a 28-year-old woman from Afghanistan without familial or personal history of blood problems or malignancies, history of any specific illness or medication. At the time of termination of pregnancy in Shahid Beheshti hospital, Kashan, Iran, she had pancytopenia (Table. 1). The patient was investigated to find the cause of pancytopenia. After termination of pregnancy, BM aspiration was carried out and its examination revealed abnormal accumulation of abnormal promyelocytic blasts. Promyelocytes included approximately 30 % of total BM cells (Figure. 1). Real time-polymerase chain reaction (RT-PCR) showed a PML-RARA fusion transcript. Low-risk APL (AML M3) was diagnosed according to the Sanz score which subdivides APL patients into three risk groups according to peripheral blood counts including: 1) low-risk APL (platelet count >40×109/L and WBC ≤10×109/L); 2) intermediate-risk APL (platelet value ≤40×109/L and WBC count ≤10×109/L); 3) high-risk APL (WBC number >10×109/L) [7, 8]. Patient was initially treated with oral ATRA (45 mg/m2/day) and intravenous Arsenic Trioxide (ATO, 0.15 mg/kg/day) until complete remission achievement. On day 26 of ATRA therapy, the patient complained of blurred vision due to retinal bleeding and had decreased consciousness, headache and seizure. Magnetic resonance imaging (MRI) result showed intra-cerebral parenchymal bleeding in the frontal lobe. The patient had no history of any specific trauma or head injury. After seizure control, the patient was treated with supportive therapies such as intravenous levetiracetam (500 mg BD) and intravenous dexamethasone (8mg/12 hours). According to the neurosurgeon consultation, the patient did not need surgery. Furthermore, some laboratory tests were employed to exclude coagulation problems and find the cause of the bleeding. Similar to the results of at the initial diagnosis, no thrombotic and hemorrhagic problems were observed (Table. 2).
On day 26 to day 32 of treatment, laboratory blood tests indicated a notable thrombocytosis with the platelet counts of 590 ×103/µl to 1280×103/µl (Figure. 2). No known causes of thrombocytosis such as infections, hemorrhagic disorders, haemolytic anemia, and iron deficiency were observed (9). Peripheral blood smear revealed a notable thrombocytosis and slight anemia (Figure. 3). Regarding the fact that the patient was asymptomatic, supportive care, ATRA, and ATO treatments were continued and ATRA dosage was not modified. Afterwards, platelet number spontaneously started to decrease on day 32 of treatment so that its number was 400×103/µl on day 42 (Figure. 2). On day 30 of ATRA therapy, BM examination showed a trilineal hematopoiesis with 1% of blasts and all criteria of morphological complete remission were observed (Figure. 4). Four consolidation courses of treatments were planned as previously described (10-13). After two consolidation courses of treatments, complete molecular remission was confirmed by the absence of PML-RARA fusion transcript using RT-PCR method.