A seven-day-old Caucasian baby girl with DS was referred to our department due to hyperleukocytosis. The baby was born by vaginal delivery at 39 weeks and two days of gestation. Her Apgar scores were 8 and 9 at one and five minutes, respectively. Her birth weight and body length were 3420 g and 49 cm, respectively. Our patient showed typical signs consistent with trisomy 21 confirmed by karyotype analysis (47, XX, +21). The second day after birth, she presented to our facility with reduced feeding intake. Peripheral blood test results revealed a white blood cell (WBC) count of 70.8 × 10
9 cells/mm
3 with 70% of blasts. Due to hyperleukocytosis our patient was referred to the Hematology Oncology Unit of the Second Pediatric Department of Aristotle University of Thessaloniki. On admission our patient had hepatosplenomegaly, abdominal distension, hypotonia and dyspnea, probably due to hyperviscosity. Echocardiography revealed a ventricular septal defect (VSD), pericardial effusion and persistent pulmonary hypertension of newborn (PPHN). An ultrasound scan of the abdomen confirmed hepatosplenomegaly with an increased echo signaling of the liver. Biochemical data revealed increasing levels of lactate dehydrogenase (LDH) (2027IU/L), serum inorganic phosphorus (P) (6.0 mg/dL) and uric acid (UA) (4.2 mg/dL). Results of blood gas analysis performed on admission were in the normal ranges. The laboratory hematological, biochemistry and coagulation test results on admission are shown in Table
1. Bone marrow aspiration revealed hypercellular marrow with an excess of blasts. Antigenitically, the blasts were negative for myeloperoxidase, positive for CD33, CD34 and CD61, and showed weak coexpression of CD7. The lymphoid and erythroid populations exhibited no antigenic aberrations or atypicality. On the basis of the blast cell immunophenotype, the presentation suggested a diagnosis of TMD. Our patient was put on antileukemic treatment with cytosine-arabinoside (Ara-C) (1.5 mg/kg per day for eight consecutive days) (day three) due to persistence of hyperleukocytosis and deterioration of respiratory function (dyspnea, tachypnea). Parental written informed consent was obtained prior to chemotherapy initiation. Biochemistry test results after initiation of antineoplastic treatment (day four) revealed increased levels of serum potassium, serum inorganic phosphorus and a marginally elevated level of uric acid (Table
1). Due to the fact that our patient had hyperleukocytosis and elevated LDH levels that meant a high tumor burden, we decided to treat her for the increased risk of TLS development. Therefore, she was put on rasburicase (0.2 mg/kg), fluid therapy and forced diuresis treatment immediately. Metabolic parameters were normalized seven days after the initiation of rasburicase treatment (day 10). Laboratory hematological, biochemistry and coagulation test values on day four (initiation of rasburicase) and 10 (end of rasburicase administration) are shown in Table
1. Peripheral blasts disappeared by day eight after the initiation of Ara-C. Due to hepatosplenomegaly and pericardial effusion, she developed mild respiratory distress without requiring ventilation. Our patient was discharged at the age of six weeks with no further complications and is currently well at the age of nine months.
Table 1
Laboratory hematological, biochemistry and coagulation test values from our patient on admission, on day four (initiation of rasburicase) and day 10 (end of rasburicase administration)
White blood cell count (cells/μL) | 70,800 | 43,500 | 4970 |
Hemoglobin (g/dL) | 17.1 | 15.8 | 15.0 |
Hematocrit (%) | 48.8 | 46.0 | 42.8 |
Platelets (cells/μL) | 248,000 | 214,000 | 118,000 |
Total protein (g/dL) | 4.90 | 4.74 | 5.16 |
Albumin (g/dL) | 3.25 | 3.26 | 3.18 |
Lactate dehydrogenase (IU/L) | 2027 | 2235 | 681 |
Urea (mg/dL) | 20 | 18 | 15 |
Creatinine (mg/dL) | 0.27 | 0.41 | 0.24 |
Sodium (mEq/L) | 140 | 140 | 137 |
Potassium (mEq/L) | 5.8 | 5.4 | 4.5 |
Phosphorus (mg/dL) | 6.0 | 5.2 | 2.8 |
Calcium (mg/dL) | 9.07 | 8.61 | 10.51 |
Uric acid (mg/dL) | 4.2 | 4.0 | 0.8 |
Alanine aminotransferase (IU/L) | 37 | 34 | 29 |
Aspartate aminotransferase (IU/L) | 14 | 20 | 20 |
Prothrombin time (seconds) | 13.8 | 12.0 | 12.2 |
Activated partial thromboplastin time (seconds) | 32.2 | 28.90 | 30.5 |
Fibrinogen (mg/dL) | 279 | 253 | 266 |