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Red blood cells (RBCs) become sickle‐shaped and stiff under hypoxia as a consequence of hemoglobin (Hb) polymerization in sickle cell anemia. Distinguishing between sickle cell disease and trait is crucial during the diagnosis of sickle cell disease. While genetic analysis or high‐performance liquid chromatography (HPLC) can accurately differentiate between these two genotypes, these tests are unsuitable for field use. Here, we report a novel microscopy‐based diagnostic test called ShapeDx™ to distinguish between disease and trait blood in less than 1 h. This is achieved by mixing an unknown blood sample with low and high concentrations of a chemical oxygen scavenger and thereby subjecting the blood to slow and fast hypoxia, respectively. The different rates of Hb polymerization resulting from slow and fast hypoxia lead to two distinct RBC shape distributions in the same blood sample, which allows us to identify it as healthy, trait, or disease. The controlled hypoxic environment necessary for differential Hb polymerization is generated using an imaging microchamber, which also reduces the sickling time of trait blood from several hours to just 30 min. In a single‐blinded proof‐of‐concept study conducted on a small cohort of clinical samples, the results of the ShapeDx™ test were 100% concordant with HPLC results. Additionally, our field studies have demonstrated that ShapeDx™ is the first reported microscopy test capable of distinguishing between sickle cell disease and trait samples in resource‐limited settings with the same accuracy as a gold standard test. [ABSTRACT FROM AUTHOR]

Objectives: Sickle cell anemia is the commonest genetic disorder in India, and the frequency of the sickle cell gene is very high in the remote tribal areas where facilities are generally limited. Therefore, a rapid and affordable point-of-care test for sickle cell disease is needed.Methods: The diagnostic accuracy of HemoTypeSC was evaluated against automated high-performance liquid chromatography (HPLC) as the gold standard for its efficacy in a newborn screening program.Results: A total of 1,559 individuals (980 newborns and 579 adults) from four participating centers were analyzed by both methods. HemoTypeSC correctly identified 209 of 211 total hemoglobin (Hb) SS cases, for a 99.1%/99.9% total HbSS sensitivity/specificity. Overall, HemoTypeSC exhibited sensitivity and specificity of 98.1% and 99.1% for all possible phenotypes (HbAA, HbAS, and HbSS) detected. HPLC is relatively expensive and not available in most laboratories in remote tribal areas.Conclusions: We conclude that the rapid, point-of-care testing device HemoTypeSC test is suitable for population and newborn screening for the HbS phenotype. [ABSTRACT FROM AUTHOR]

The article presents a study related to sickle cell disease screening and follow-up programme for the newborn infants in the tribal populations of South Gujarat, India. It mentions that high performance liquid chromatography with molecular analysis was used in 5467 newborn babies and were clinically followed-up and haematologically regularly for 1.5 to 5 years and results shows that 33 babies are sickle homozygous, 13 are thalassaemia, and 687 are heterozygous while 4736 are unaffected.

Dithionite Tube Turbidity (DTT) Test is used as a primary screening method for sickle hemoglobin in field screening as well as in routine laboratories. Even though it is not very reliable in terms of sensitivity and specificity, due to its simplicity and cost effectiveness, it is the only method feasible for mass field screening. Various DTT test buffer compositions and test procedures for performing test are prevailing in literature. This study was performed to find out the most appropriate DTT test buffer to enhance sensitivity and specificity which is suitable for the field conditions. We have found total of thirteen different chemical compositions for DTT test buffer preparation from literature review and visited existing users of the test. In order to know the best composition of DTT test buffer, total 128 well characterized clinical samples were analyzed with all different types of DTT buffers. Out of these thirteen DTT test buffer compositions, seven compositions have shown higher sensitivity and specificity. By considering the importance of visual result interpretation of the DTT test, out of these seven DTT test buffer compositions, four compositions have shown the easiest visual result interpretation, which would be user friendly and can be very easily adopted for field screening. By adopting this test procedure and DTT test buffer composition, one can easily decrease the rate of false positive and false negative test results during sickle cell screening. [ABSTRACT FROM AUTHOR]

We evaluated the spectrum of hemoglobinopathies among the primitive tribal groups from 4 states in India. A total of 15 200 individuals from 14 primitive tribal groups were studied by automated high-performance liquid chromatography. The hemoglobin S (HbS) allele frequency varied from 0.011 to 0.120 and the β-thalassemia allele frequency from 0.005 to 0.024. It is interesting to note that a very high HbS allele frequency was observed among the Dravidian (0.060-0.120) and Indo-European (0.060-0.076) as compared with Austro-Asiatic (0.011-0.022) speaking tribal groups. Although statistical analysis of the data did not show any ethnic differences within the states, regional differences were observed between the states for both HbS and β-thalassemia traits. HbS was found to be the most common hemoglobinopathy followed by β-thalassemia. A health plan for identifying sickle-cell homozygotes in the neonatal period with proper medical intervention is desirable. [ABSTRACT FROM PUBLISHER]

Red blood cells (RBCs) become sickle-shaped and stiff under hypoxia as a consequence of hemoglobin (Hb) polymerization in sickle cell anemia. Distinguishing between sickle cell disease and trait is crucial during the diagnosis of sickle cell disease. While genetic analysis or high-performance liquid chromatography (HPLC) can accurately differentiate between these two genotypes, these tests are unsuitable for field use. Here, we report a novel microscopy-based diagnostic test called ShapeDx™ to distinguish between disease and trait blood in less than 1 h. This is achieved by mixing an unknown blood sample with low and high concentrations of a chemical oxygen scavenger and thereby subjecting the blood to slow and fast hypoxia, respectively. The different rates of Hb polymerization resulting from slow and fast hypoxia lead to two distinct RBC shape distributions in the same blood sample, which allows us to identify it as healthy, trait, or disease. The controlled hypoxic environment necessary for differential Hb polymerization is generated using an imaging microchamber, which also reduces the sickling time of trait blood from several hours to just 30 min. In a single-blinded proof-of-concept study conducted on a small cohort of clinical samples, the results of the ShapeDx™ test were 100% concordant with HPLC results. Additionally, our field studies have demonstrated that ShapeDx™ is the first reported microscopy test capable of distinguishing between sickle cell disease and trait samples in resource-limited settings with the same accuracy as a gold standard test., Competing Interests: Two Indian patent applications have been filed for the portable microscopes, which are licensed to MedPrime Technologies. Samrat, one of the authors of this manuscript, is the CEO and co‐founder of MedPrime Technologies. An Indian patent and an Indian trademark application have been filed for the diagnostic test referred to as ShapeDx™ in this manuscript. Both the patent and the trademark are licensed to Lords Mark Technologies Pvt. Ltd. Neither MedPrime Technologies nor Lords Mark Technologies Pvt. Ltd have contributed financially to the project or have had any influence over the research direction. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 The Authors. Bioengineering & Translational Medicine published by Wiley Periodicals LLC on behalf of American Institute of Chemical Engineers.)