A two-year-old boy was admitted to hospital with distension for one day.He was sweaty and had dense papules scattered on his head and face. The distension was immediately apparent, with an abdominal circumference of 59 cm and visible venous shadowing in the abdominal wall. A huge mass could be palpated during digital rectal examination. Computer Tomography (CT) revealed diffuse lesions on the liver, gallbladder, kidneys, intestinal tubes, and peritoneum as well as neoplastic lesions (indicative of lymphoma), left oblique inguinal hernia and bilateral pleural effusions. The abdominal ultrasound revealed multiple hypoechoic masses in the abdomen-pelvic cavity; likewise in the liver; multiple segments of thickened intestinal wall (considering lymphoma). The results from an electrocardiogram were normal. However, serum biochemistry tests were abnormal, showing aspartate aminotransferase of 137U/L, lactate dehydrogenase (LDH) of 1698U/L, and α-hydroxybutyrate dehydrogenase of 1132U/L. Serum electrolytes were close to normal levels. Uric acid level was 902umol/L. Urinalysis yielded excess of urobilinogen, ketone, protein and specific gravity of 1 0.035. Sternal bone marrow puncture showed no obvious abnormalities. Bone marrow biopsy was not performed. Due to the high tumor burden, intravenous hyperhydration (1500ml/m2), alkalization of urine (sodium bicarbonate 1.5 g/d) and diuresis (furosemide 10 mg/d) were administered preoperatively. The average daily urine output was 415 ml and uric acid decreased slightly to 877umol/L two days later. The tumor was shown to be exceptionally large, and the child’s abdominal distension progressed rapidly. In order to confirm the diagnosis as soon as possible, an open tumor biopsy was performed on the third day of admission. General anesthesia was induced using intravenous mivacurium chloride and maintained by sevoflurane via endotracheal tube. After locating the tumor by B-ultrasound, a 3 cm wide transverse incision was made into the upper abdomen. The tumor was seen at the lower margin of the right lobe of the liver and was adherent to surrounding tissues. Omentum was thickened, edemateous and was pale in color. One cubic cm samples of both the tumor and omentum tissue were removed and sent in for pathological examination. Rapid pathology revealed that the tumor was malignant and had metastasized to the omentum. The child suddenly developed tachycardia (∼ 190 beats/min) as the abdominal incision was being closed. Electrocardiography revealed widened QRS complexes and high-pointed T waves. Both physical cooling and dexibuprofen embolization were performed, as his body temperature had risen to 41.3 °C. In addition, an intravenous lidocaine injection was administered, and the child’s heart rate gradually decreasing to 25 beats/min. This prompted chest compression and an intravenous injection of epinephrine, after which the heart rate converted to a sinus rhythm of ∼ 95 beats/min. A blood sample sent for laboratory examination revealed a serum potassium level of 6.99 mmol/l; total calcium of 1.09 mmol/l: PH of 7.041; BE of -14.1. Despite multiple intravenous injections of sodium bicarbonate, calcium gluconate, epinephrine, insulin and furosemide, the patient’s heart rate remained unstable. A diagnosis of STLS was considered. After a temporary return to normal heart rhythm and autonomous respiration, the patient was immediately transferred to the surgical intensive care unit (SICU). The initial blood results in the SICU showed that potassium levels had risen to 7.38 mmol/l and blood uric acid to 1145 umol/l, while total calcium concentration had fallen to 1.18 mmol/l. Alanine transaminase (ALT) was recorded at 1909 U/L and oxaloacetic transaminase (AST) at 7306 U/L. CRRT was initiated due to persistently elevated serum potassium levels. A continuous venous-venous hemodiafiltration (CVVHDF) mode was adopted. After the initiation of CVVHDF, the arrhythmias decreased in frequency and after 6 h, serum potassium had dropped to 4.92 mmol/l. In addition, blood uric acid decreased to 207 umol/l at 4 days postopderatively. The final pathological diagnosis confirmed Burkitt lymphoma. The patient was weaned from CVVHDF 4 days post-operation and was successfully extubated six days after the operation. His liver gradually recovered, exhibiting stable bloodwork results(ALT of 248 U/L, AST of 127 U/L, alkaline phosphatase (ALP) of 119 U/L, γ-glutamyl transferase (GGT) of 142 U/L). We observed that kidney function returned to normal over the next 10 days. The abdominal circumference was reduced to 55 cm. Prior to chemotherapy, rasburicase, which can reduce uric acid, hydration and alkalinization were administered to prevent TLS. He is currently on maintenance chemotherapy and has had no further episodes of TLS.