From the Guidelines
Allopurinol should be used with caution in patients undergoing stem cell transplantation, with a typical dosage ranging from 300-600 mg daily, starting 2-3 days before conditioning chemotherapy and continuing through the early post-transplant period, as it can prevent tumor lysis syndrome and manage hyperuricemia, but may also cause adverse effects such as rash, gastrointestinal disturbances, and elevated liver enzymes 1.
Key Considerations
- The dosage of allopurinol may need to be adjusted in patients with renal impairment, with reduced doses of 100-200 mg daily for those with creatinine clearance below 60 ml/min 1.
- Allopurinol can cause an increase in serum levels of the purine precursors xanthine and hypoxanthine, leading to a risk of xanthine crystal deposition in the renal tubules and acute obstructive uropathy 1.
- The use of allopurinol may also require dose reductions of other purine-based chemotherapeutic agents, such as 6-mercaptopurine and azathioprine, due to reduced clearance 1.
Monitoring and Alternative Treatment
- Regular monitoring of uric acid levels, renal function, and liver enzymes is essential during treatment to ensure efficacy and detect potential toxicity early 1.
- For patients with severe hyperuricemia or those who cannot tolerate allopurinol, rasburicase may be used as an alternative, as it has been shown to be effective in reducing serum uric acid levels in adults and children 1.
From the Research
Allopurinol and Stem Cell Transplant
- Allopurinol is used to prevent tumor lysis syndrome (TLS) in patients undergoing hematopoietic stem cell transplantation 2, 3, 4
- TLS is a common cause of acute kidney injury in patients with malignancies, and it is a frequent condition for which the nephrologist is consulted in the case of the hospitalized oncological patient 5
- The use of allopurinol in renal failure or situations of purine overproduction requires careful monitoring of plasma oxipurinol levels to avoid overdosage and side effects 6
Rasburicase and Allopurinol
- Rasburicase is effective in lowering uric acid levels at a fixed dose of 3 mg, which is much lower than the recommended dose 3
- Rasburicase is more effective than allopurinol in controlling plasma uric acid in adults at risk for tumor lysis syndrome 4
- The combination of rasburicase and allopurinol may be used to control plasma uric acid in patients at high risk for TLS 4
Stem Cell Transplant and Tumor Lysis Syndrome
- Hematopoietic stem cell transplantation is a risk factor for tumor lysis syndrome 5
- Patients undergoing stem cell transplantation may require prophylactic treatment with allopurinol or rasburicase to prevent TLS 2, 3, 4
- The management of TLS requires a multidisciplinary team approach to reduce the risk of death and chronic renal impairment 5