Project Lead(s): Julie Shaw
The increased prevalence of diabetes and hypertension in the developing world has resulted in an increased incidence of kidney disease which, if left untreated, can progress to end-stage renal failure (ESRD) requiring dialysis, which is costly and not readily available.
Routine reporting of the estimated glomerular filtration rate (eGFR) has been recommended for monitoring of renal function by several international organizations but requires standardized creatinine measurements.
The project in Guyana involved assessing how accurate and precise laboratories are in their measurement of creatinine and to understand the impact of creatinine method performance on patient classification by estimated glomerular filtration rate (eGFR).
A total of sixteen laboratories from across Guyana were studied, including six public and ten private clinical laboratories.
The project team assessed the dimension of inaccurate creatinine measurements, the impact of intervening to improve the standardization of test results and the derived benefit, based on feedback from labs, physicians and the public Educational materials aimed at public awareness of chronic kidney disease and prevention strategies were created, and provided to laboratories and physicians for public dissemination. Data were generated on the performance of creatinine methods in Guyana. The potential impact of creatinine method standardization was demonstrated by comparing the incidence of kidney disease in Guyana, based on eGFR, calculated using current creatinine results corrected for measurement bias.
Imprecision and bias of methods used to measure creatinine values were documented in the participating laboratories, which may impact the use of estimated glomerular filtration rate (eGFR) for clinical management.
eGFR calculations using creatinine methods as they currently perform in Guyana would lead to the misclassification of approximately 50,000 Guyanese as having Stage 3 kidney disease and requiring treatment.
Most labs in Guyana use heterogeneous, open testing systems for measuring creatinine and the majority of participating labs in this study demonstrated imprecision far exceeding that which is considered acceptable for creatinine.
Creatinine methods in Guyana generally exhibit positive bias when compared to measurements made by the international reference method (IDMS).
Dedicated education on strategies aimed at improving method performance are required.
A common source of “truth” in the form of a common measurement method for creatinine in Guyanese labs would help reduce bias in testing.
Results from this investigation have been presented at meetings and as a poster at the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC World Conference, Istanbul, Turkey). Manuscripts describing the project were prepared for publication.