Subclinical PNH can be present in patients with bone marrow failure like aplastic anemia and myelodysplastic syndrome (MDS). Such clone may have prognostic and therapeutic implications. In literature around 1-10% MDS cases have shown a PNH clone, however, data from India is relatively scarce. A high sensitivity PNH assay was employed using a single tube combination of FLAER, CD157, CD64, CD15 and CD45 antibodies in adult patients of MDS at presentation. A clone size of > 0.01% was taken as significant. A total of 30 patients were included. PNH clone was present in 30% cases. Correlation done between PNH clone size and LDH values showed moderately positive correlation (r = 0.735, p = 0.001, r2 = 0.541). As per this study a LDH cut off of 247 IU is likely to predict a PNH clone (> 1%) with moderate sensitivity and specificity. High sensitivity PNH assay is able to detect small PNH clone. Calculating the cut-off of LDH to predict PNH positivity can help us judiciously prescribe this test in MDS patients in resource constrained settings.
Keywords: Hemolysis; High sensitivity PNH assay; Myelodysplastic syndrome; PNH clone; Paroxysmal nocturnal hemoglobinuria (PNH).
© Indian Society of Hematology and Blood Transfusion 2019.