What are the monitoring and management recommendations for tumor lysis syndrome?

Monitoring and Management of Tumor Lysis Syndrome

Patients at high risk for tumor lysis syndrome (TLS) should receive rasburicase, aggressive hydration, and frequent laboratory monitoring in an inpatient setting with access to dialysis. 1

Risk Assessment

High-Risk Patients

• Host factors: Dehydration, hyponatremia (in solid tumors), pre-existing renal impairment, obstructive uropathy, hyperuricemia (>8 mg/dL in children, >10 mg/dL in adults) 1
• Disease factors: Bulky disease, high-grade lymphomas (particularly Burkitt's lymphoma), acute lymphoblastic leukemia, elevated LDH (>2× upper normal limit) 1
• Therapy factors: Intensive polychemotherapy including cisplatin, cytosine arabinoside, etoposide, methotrexate 1

Monitoring Recommendations

For High-Risk Patients:

• Before treatment: Assess creatinine clearance, serum LDH levels, and renal ultrasound 1
• During prevention/treatment:
  • Monitor uric acid, phosphate, potassium, creatinine, calcium, and LDH every 12 hours for first 3 days, then every 24 hours 1
  • Evaluate fluid input and urine output continuously 1

For Patients with Active TLS:

• Every 6 hours for first 24 hours:
  • Vital signs (heart rate, blood pressure, urine output, respiratory rate)
  • Serum uric acid, electrolytes (phosphate, calcium, potassium)
  • Renal function (creatinine, BUN, urine pH, osmolality) 1
• Every 24 hours:
  • CBC, LDH, albumin, serum osmolality, blood gases, acid-base status
  • ECG and body weight 1

Management Protocol

Prevention in High-Risk Patients:

1. Hydration:

   • Start 48 hours before chemotherapy when possible 1
   • Maintain urine output ≥100 mL/hour in adults (3 mL/kg/hour in children <10 kg) 1, 2
   • Consider loop diuretics if needed to maintain output (avoid in obstructive uropathy or hypovolemia) 1

2. Hyperuricemia Management:

   • Rasburicase: 0.20 mg/kg/day IV over 30 minutes 1
     • Administer first dose ≥4 hours before starting chemotherapy 1
     • Continue for 3-5 days 1
     • Contraindicated in G6PD deficiency or metahemoglobinemia 1
     • Achieves rapid uric acid reduction with 96% of patients reaching levels ≤2 mg/dL within 4 hours 3
   • Allopurinol: 100 mg/m² three times daily (maximum 800 mg/day) for low-risk patients 1
     • Do not administer concurrently with rasburicase 1

Treatment of Established TLS:

1. Hyperkalemia Management:

   • Verify elevated levels with second sample to rule out hemolysis 1
   • For asymptomatic patients: Sodium polystyrene sulfonate 1 g/kg with 50% sorbitol orally/rectally 1
   • For symptomatic patients or K+ >7.0-7.5 mEq/L:
     • Rapid-acting insulin (0.1 U/kg IV) with glucose (25% dextrose 2 mL/kg) 1
     • Sodium bicarbonate (1-2 mEq/kg IV push) 1
     • Calcium gluconate (100-200 mg/kg/dose) for life-threatening arrhythmias 1
     • Monitor ECG continuously 1

2. Hypocalcemia Management:

   • For asymptomatic patients: No intervention recommended 1
   • For symptomatic patients: Calcium gluconate 50-100 mg/kg IV slowly with ECG monitoring 1
   • Use caution with high phosphate levels due to risk of calcium phosphate precipitation 1

3. Hyperphosphatemia Management:

   • Phosphate binders (not specifically detailed in guidelines)
   • Obtain renal consultation for persistent elevation 1

Dialysis Indications

Obtain immediate nephrology consultation for:

• Urine output below target
• Persistent/elevated phosphate levels
• Hypocalcemia
• Severe hyperkalemia unresponsive to medical management 1

High-risk patients should only receive chemotherapy in facilities with ready access to dialysis 1

Common Pitfalls and Caveats

1. Urine alkalinization: Generally not recommended with rasburicase as it can increase calcium phosphate precipitation and reduce xanthine solubility 1

2. Calcium administration: Use cautiously in hypocalcemia as it may increase calcium phosphate precipitation; however, it remains important for treating life-threatening hyperkalemia-induced arrhythmias 1

3. Monitoring duration: If TLS has not occurred after 2 days, the likelihood of developing it is essentially zero 1

4. Rasburicase contraindications: Screen for G6PD deficiency before administration, particularly in at-risk populations 1

5. Concomitant medications: Avoid nephrotoxic medications (NSAIDs, certain antibiotics) during TLS management 2