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Hydroxyurea interferes with point-of-care creatinine testing in children with sickle cell anemia
Ruth Namazzi1, Robert O Opoka2, Charles Ssuuna3
1Department of Pediatrics and Child Health, Makerere University College of Health Sciences, Kampala, Uganda.
BMC Research Notes
|June 19, 2026
Summary
Hydroxyurea interferes with i-STAT creatinine tests in children with sickle cell anemia (SCA), potentially misdiagnosing kidney function. This interference impacts clinical decisions for SCA patients on hydroxyurea therapy.
Area of Science:
- Pediatric Nephrology
- Hematology
- Clinical Diagnostics
Background:
- Sickle cell anemia (SCA) affects children globally, requiring careful monitoring of kidney function.
- Point-of-care testing offers rapid results but requires validation for specific patient populations and treatments.
- Hydroxyurea is a common treatment for SCA, but its potential interference with diagnostic assays is a concern.
Purpose of the Study:
- To assess the accuracy of the i-STAT device for creatinine measurement in Ugandan children with SCA.
- To investigate the clinical significance of assay interference caused by hydroxyurea.
Main Methods:
- Secondary analysis of a randomized clinical trial involving 248 Ugandan children with SCA.
- Comparison of creatinine levels measured by i-STAT and a reference laboratory.
- Correlation of i-STAT creatinine values with serum hydroxyurea concentrations.
Main Results:
- i-STAT and reference lab creatinine values were comparable at baseline.
- Children on hydroxyurea showed significantly higher i-STAT creatinine levels compared to reference lab values (p=0.006).
- Hydroxyurea concentration explained 73% of the variability in i-STAT creatinine results.
Conclusions:
- Hydroxyurea causes clinically significant interference with point-of-care creatinine testing using the i-STAT device.
- This interference may lead to misclassification of kidney function in children with SCA receiving hydroxyurea.
- Careful consideration of assay interference is crucial for appropriate clinical decision-making in this population.
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