Saroj Ranjan Mohanty1 , Samira Kumar Behera2 , Sonali Kar3
BACKGROUND Sickle cell anaemia is the most common disease entity of all the monogenic disorders. In the absence of any definitive treatment, to reduce the disease burden and the associated morbidity and mortality, a simple, low-cost test to assess the presence of Hb S and also to differentiate the homozygous and heterozygous forms, is required. METHODS This study was carried out in the Department of Pathology of MKCG Medical College, Berhampur, where samples of 130 cases (50 cases of sickle cell trait and 50 cases of homozygous sickle cell disease along with 30 cases of normal haemoglobin pattern) diagnosed by CE-HPLC were subjected to modified haemoglobin solubility testing and cases were classified as Hb AA, Hb AS and Hb SS depending upon presence/absence of red precipitate and colour of lower layer. RESULTS Out of the 130 cases in the study, there was agreement with the findings of CEHPLC in 123 cases (accuracy of 94.62%). All 50 cases of homozygous SCD formed a red precipitate, but in 4 of those cases a diagnosis of SCT was made by the solubility test. Similarly, 47 of 50 trait cases were correctly diagnosed but other 3 cases were diagnosed as having normal pattern. Sensitivity and specificity of the solubility test in differentiating cases of homozygous and heterozygous sickle cell disease came out to be 92% and 100% respectively. CONCLUSIONS The modified haemoglobin solubility test is a simple and cheap test with high degree of accuracy that can be carried out by health workers at the peripheral level, with minimum requirement of training and equipment. It can be used as a preliminary screening as well as differentiating test.
