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Tumor Lysis Syndrome — Risk Stratification, Hydration, and Uric Acid Control

System: Hematology Oncology • Reviewed: Sep 1, 2025 • Step 1Step 2Step 3

Synopsis:

TLS arises after cytotoxic therapy (or spontaneously) in high-burden hematologic malignancy. Prevent with aggressive isotonic fluids, strict monitoring of potassium, phosphate, calcium, uric acid, and renal function, and early uric acid–lowering therapy (rasburicase for high risk).

Key Points

  • Confirm diagnosis early with highest-yield tests (e.g., MRV for CVST, CTA for mesenteric ischemia).
  • Dose-and-route precision for high-risk medications; monitor for adverse effects.
  • Explicit ICU criteria and consultation triggers.

Clinical Synopsis & Reasoning

TLS arises after cytotoxic therapy (or spontaneously) in high-burden hematologic malignancy. Prevent with aggressive isotonic fluids, strict monitoring of potassium, phosphate, calcium, uric acid, and renal function, and early uric acid–lowering therapy (rasburicase for high risk).


Treatment Strategy & Disposition

Stabilize airway/breathing/circulation; initiate guideline-concordant first-line therapy; tailor escalation or de-escalation to clinical response and objective metrics; define clear disposition criteria (e.g., ICU triggers, ward acceptability, outpatient safety).


Epidemiology / Risk Factors

  • Risk varies by comorbidity and precipitating factors

Investigations

TestRole / RationaleTypical FindingsNotes
CBCAnemia/leukocytosisContext-specificTrend with therapy
BMPElectrolytes/renalDerangements commonRenal dosing
Condition-specific imagingSee topicDiagnostic hallmarkDo not delay when red flags present

Pharmacology

MedicationMechanismOnsetRole in TherapyLimitations
RasburicaseRecombinant urate oxidaseHoursRapidly lowers uric acid in high-risk TLS (typical 0.2 mg/kg IV x1)Contraindicated in G6PD deficiency
AllopurinolXanthine oxidase inhibitorDaysProphylaxis in intermediate risk (100–300 mg PO daily)Prevents new uric acid formation; does not reduce existing
Normal salineCrystalloidImmediateHigh-rate hydration to maintain urine outputAdjust for cardiac/renal status

Prognosis / Complications

  • Outcome depends on timeliness of diagnosis and definitive therapy

Patient Education / Counseling

  • Explain red flags, adherence, and follow-up plan

References

  1. Authoritative guideline/review; see internal bibliography — Link

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