Accra: People with sickle cell trait-those who carry one sickle cell gene but do not have sickle cell disease-may require specialized blood sugar testing to accurately detect and manage pre-diabetes and diabetes, researchers in Ghana have found. The study, presented at ADLM 2026 in Anaheim, California, highlighted the limitations of immunoturbidimetry, a commonly used laboratory assay for measuring haemoglobin A1c (HbA1c), in accurately diagnosing diabetes in individuals with sickle cell trait.
According to Ghana News Agency, the study found that immunoturbidimetry significantly underestimated blood sugar levels in people with sickle cell trait compared with high-performance liquid chromatography (HPLC), a method that separates and quantifies components in liquid samples. Researchers warned that relying on immunoturbidimetry alone could lead to under-classification of pre-diabetes and missed diabetes diagnoses in such individuals.
Dr Elikem Kumahor, lead author and Specialist Laboratory Physician at Korle Bu Teaching Hospital, emphasized the relevance of these findings in Ghana, where the prevalence of sickle cell disease and sickle cell trait is notably high. "We have a high prevalence of sickle cell disease-about two per cent of all newborns-and sickle cell trait in about 30 per cent of the Ghanaian population. However, the influence of haemoglobin variants on HbA1c testing has not been well characterised in our region," he stated.
The study analyzed 1,283 consecutive HbA1c tests conducted on patients aged 18 years and above at a tertiary hospital in Accra between January and February 2026. Initial testing was done using HPLC, which automatically detects haemoglobin variants. Of the samples, 256 with suspected variants were re-analysed using immunoturbidimetry, while sickle cell trait was confirmed through haemoglobin electrophoresis.
The results revealed significant discrepancies between the two testing methods. Among participants with normal haemoglobin, both methods produced similar HbA1c results. However, in those with sickle cell traits, immunoturbidimetry significantly underestimated HbA1c levels compared with HPLC, recording an average of 5.1 per cent against 5.9 per cent.
Using immunoturbidimetry, only 11.1 per cent of the 198 HbAS participants were classified as pre-diabetic, compared with 34.5 per cent using HPLC. HPLC also identified four per cent of participants with diabetes, while none were diagnosed through immunoturbidimetry.
Dr Kumahor noted that although HbA1c is widely used as a non-fasting test for diagnosing and monitoring diabetes, its clinical utility might be limited in regions with a high prevalence of haemoglobin variants. He recommended haemoglobin genotype testing for people living with diabetes or those undergoing routine diabetes screening to improve diagnostic accuracy.
Understanding the limitations of immunoassays would help shape laboratory protocols and policies for diabetes testing in Ghana and other parts of West Africa, Dr Kumahor added.