By Maxwell Awumah
Ho, July 31, GNA – People with sickle cell trait—those who carry one sickle cell gene but do not have sickle cell disease—may require specialised blood sugar testing to accurately detect and manage pre-diabetes and diabetes, researchers in Ghana have found.
The study found that immunoturbidimetry, a commonly used laboratory assay for measuring haemoglobin A1c (HbA1c), 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 said relying on immunoturbidimetry alone could lead to under-classification of pre-diabetes and missed diabetes diagnoses in such individuals. The findings were presented at ADLM 2026 in Anaheim, California.
Dr Elikem Kumahor, lead author and Specialist Laboratory Physician at Korle Bu Teaching Hospital, said Ghana’s high prevalence of sickle cell disease and sickle cell trait made the findings particularly relevant.
“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 said.
“Our study indicates that relying on immunoassays alone likely contributes to significant underdiagnosis of diabetes. We recommend adopting methods that account for haemoglobin variants, such as HPLC, or introducing mandatory reflex testing algorithms for accurate diabetes assessment in high-risk populations.”
The researchers analysed 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 study classified 1,027 participants as HbAA (normal haemoglobin) and 198 as HbAS (sickle cell trait), excluding 58 participants with other haemoglobin variants.
Among participants with normal haemoglobin, both testing 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 22 of the 198 HbAS participants (11.1 per cent) were classified as pre-diabetic, compared with 68 participants (34.5 per cent) using HPLC. HPLC also identified eight participants (four per cent) with diabetes, while none were diagnosed through immunoturbidimetry.
Dr Kumahor said the findings showed that HbA1c results obtained through immunoturbidimetry were significantly lower in people with sickle cell traits than those obtained using HPLC.
He noted that although HbA1c was 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.
Dr Kumahor said understanding the limitations of immunoassays would help shape laboratory protocols and policies for diabetes testing in Ghana and other parts of West Africa.
GNA
Edited by: Audrey Dekalu