From the Guidelines
An elevated uric acid workup in pediatrics involves a systematic evaluation when a child presents with hyperuricemia (serum uric acid levels above 5.5-6.0 mg/dL), and management depends on the underlying cause, which may include dietary modifications, weight management, and medications such as allopurinol (starting at 5-10 mg/kg/day) or febuxostat, as recommended by guidelines for the management of pediatric and adult tumor lysis syndrome: an evidence-based review 1.
Key Components of the Workup
- Comprehensive history focusing on family history of gout, kidney stones, or metabolic disorders
- Physical examination looking for joint inflammation, tophi, or signs of underlying conditions
- Laboratory testing, including:
- Complete blood count
- Comprehensive metabolic panel
- Urinalysis
- Urine uric acid-to-creatinine ratio
- 24-hour urine collection for uric acid excretion
- Additional tests, such as renal ultrasound to check for stones or nephrocalcinosis, and genetic testing for inherited disorders of purine metabolism like Lesch-Nyhan syndrome or HPRT deficiency
Common Causes of Pediatric Hyperuricemia
- Obesity
- Metabolic syndrome
- Certain medications (diuretics, cyclosporine)
- Renal insufficiency
- Tumor lysis syndrome
- Genetic disorders
Management
- Dietary modifications (reducing purine-rich foods, limiting fructose intake)
- Weight management for obese children
- Medications, such as allopurinol (starting at 5-10 mg/kg/day) or febuxostat, in symptomatic cases
- Monitoring rather than immediate treatment for asymptomatic hyperuricemia without evidence of tissue deposition or kidney disease
Importance of Early Identification and Management
Early identification and management are crucial to prevent complications like gout, kidney stones, or kidney damage in children with persistently elevated uric acid levels, as highlighted in the guidelines for the management of pediatric and adult tumor lysis syndrome: an evidence-based review 1.
From the FDA Drug Label
The upper limit of normal is about 7 mg/dL for men and postmenopausal women and 6 mg/dL for premenopausal women. For patients <13 years, achievement of uric acid concentration ≤6.5 mg/dL, and for patients ≥13 years, ≤7.5 mg/dL An elevated uric acid level in pediatrics is generally considered to be above the upper limit of normal, which is:
- ≤6.5 mg/dL for patients <13 years
- ≤7.5 mg/dL for patients ≥13 years 2 In the context of the provided drug labels, an elevated uric acid workup in pediatrics would involve monitoring and managing uric acid levels to prevent complications such as tumor lysis syndrome (TLS) or kidney damage 3.
From the Research
Elevated Uric Acid Workup in Pediatrics
Elevated uric acid levels in children and adolescents can be an indicator of various underlying conditions. The following are some key points to consider:
- Hyperuricemia is an important condition in children and adolescents, particularly in association with noncommunicable diseases 4.
- The major causes of hyperuricemia in pediatric patients include chronic conditions such as Down syndrome, metabolic or genetic disease, and congenital heart disease, as well as acute conditions like gastroenteritis, bronchial asthma, and malignant disorders 4.
- Obesity is a significant cause of hyperuricemia in otherwise healthy children and adolescents, and is often accompanied by metabolic syndrome 4, 5.
- Hyperuricemia is also associated with an increased risk of impaired renal function, and early treatment of hyperuricemia may help control chronic renal disease 6.
Diagnostic Approach
When evaluating a child with elevated uric acid levels, the following steps can be taken:
- Assess serum uric acid concentration and correlate it with clinical and biochemical parameters 7.
- Consider the patient's age, sex, and weight, as these factors can influence uric acid levels 5, 7.
- Evaluate for underlying conditions such as obesity, metabolic syndrome, and renal disease 4, 5, 6.
- Use lactate dehydrogenase and uric acid as screening tools for malignancies in children, although their specificity may be lower than their sensitivity 8.
Management
Treatment of hyperuricemia in pediatric patients may involve:
- Lifestyle interventions, such as dietary changes and weight management 4.
- Urate-lowering therapy, such as allopurinol, which can be effective in normalizing serum uric acid levels 5.
- Individualized management approaches, taking into account the underlying cause of hyperuricemia and the patient's overall health status 5.