2: Oncological Emergencies - TLS Flashcards
What is tumour lysis syndrome
Metabolic abnormalities caused by rapid destruction of tumour cells - leads to renal failure
When is TLS most common
Following induction of chemotherapy for leukaemia and lymphoma
How long after chemotherapy does TLS symptoms manifest
Days
What scoring system is used for TLS
Cario-Bishop Scoring System
What does Cario-Bishop Scoring system state must be present
Two laboratory criteria present 3d before and 7d after chemotherapy
- Hyperphosphataemia (25% Increase)
- Hyperuraecaemia (25% Increase)
- Hyperkalaemia (25% Increase)
- Hypocalcaemia (25% decrease)
What are the 4 electrolyte abnormalities in TLS
- High Uric Acid
- High Potassium
- High Phosphate
- Low calcium
What is clinical TLS
Laboratory criteria and one of:
- Arrhythmias
- Seizures
- Increase serum creatinine (1.5 times limit)
What causes high potassium in TLS
Renal Failure
What does high potassium cause
Cardiac arrhythmias
What causes high phosphate in TLS
Tumour cells usually contain higher phosphate - rupture cause phosphate release
What does high phosphate cause
Binds with calcium and precipitates to cause:
- Renal damage
- Arrhythmias (heart)
- Gangrene (skin)
What cause high uric acid in TLS
- Renal failure
- Release uric acid used to make DNA
What does high uric acid cause
- Renal failure
What causes low calcium in TLS
Binds to phosphate
What does low calcium cause
Weakness
Tetancy
What is given as prophylaxis to prevent all possible cases of TLS
Hydration with IV Fluid
What is given to prevent intermediate-risk cases of TLS
Allopurinol
What is the MOA of allopurinol
Inhibits xanthine oxidase. Preventing xanthine producing uric acid
When is allopurinol started to prevent TLS
48h
What is given to prevent high-risk cases of TLS
Rasburicase
What is the MOA of rasburicase
Increases metabolism uric acid to allantoin
What is an absolute CI to giving rasburicase
G6PD
How is TLS managed
- FLuid
- Dialysis if high uric acid
