الفهرس | Only 14 pages are availabe for public view |
Abstract Thrombocytopenia is a common clinical problem manifested by decrease of platelet count which may be life threatening sometimes. There are two major causes for thrombocytopenia: Hyperdestructive thrombocytopenia and Hypoproductive thrombocytopenia. Diagnosis of both types of thrombocytopenia is based on several laboratory investigations for discrimination between them. Among these investigations are platelet indices which are mean platelet volume (MPV), platelet distribution width (PDW) and platelet large cell ratio (P-LCR). The aim of this study was to evaluate the significance of platelet indices in the diagnosis of thrombocytopenia by comparing the levels in hyper-destructive thrombocytopenia (ITP) and hypo-productive thrombocytopenia. The sensitivity and specificity of platelet indices to enable the diagnosis of ITP were also evaluated aiming to settle a cut off value for MPV, PDW and P-LCR. This study included eighty patients presented with thrombocytopenia, classified as follows: group I included forty patients with newly diagnosed idiopathic thrombocytopenic purpura (ITP). group II included ten patients with aplastic anemia (AA), 17 patients with acute leukemia (AL), 3 patients with myelodyplasia (MDS) and 10 patients under treatment with chemotherapy. Patients were recruited from Ain Shams University Hospitals in the clinical and chemical pathology department. Twenty healthy age and sex matched individuals were selected for comparison as control group. In ITP patients group, we found that the MPV and P-LCR were significantly higher in comparison to either control group or hypoproductive group.The best cut off value of MPV for differentiation between ITP and hypoproductive thrombocytopenia was >9. 7 fl with a diagnostic sensitivity 57. 5% and specificity 82. 5%, negative predictive value 66% and positive predictive value 76. 6%, while best cut off of P-LCR for differentiation between ITP and hypoproductive thrombocytopenia was >33. 6 % with a diagnostic sensitivity 100% and specificity 97. 5%, negative predictive value 100% and positive predictive value 97. 6%. A significant positive correlation was found between the three platelet indices MPV, PDW and P-LCR in destructive thrombocytopenia and hypoproductive thrombocytopenia, while no significant correlation was found between platelet count and the three platelet indices MPV, PDW and P-LCR neither in ITP nor in hypoproductive thrombocytopenia. As regard PAIgG detection revealed no significant difference between patients and controls and between different patient subgroups as well as low specificity and sensitivity to diagnose ITP. Thus, not reliable as a routine test to diagnose ITP. Thus, our study concludes that increased MPV and PLCR may provide a reliable positive diagnosis of ITP in case of thrombocytopenic patients. This study points to the importance of evaluating platelet indices especially MPV and P-LCR to the thrombocytopenia investigations as they provide a reliable positive diagnosis of ITP from this study, we could be concluded that: - Measuring of platelet indices (MPV and P-LCR) provides useful diagnostic test in differentiating ITP from hypoproductive thrombocytopenia, thus may avoid the need for bone marrow examination. - PDW cannot be considered a differentiating measure in distinguishing ITP from hypoproductive thrombocytopenia. - Measurement of Platelet associated immunoglobulin G (PAIgG) is not a reliable test in diagnosis of ITP. |