Platelet Changes in Cases of Chronic Iron Over Load

Iron demand: The average daily demand to fit the cell biological metabolism is balanced between intake and lost which about 1-2 mg. One unit of packed red blood cells contains approximately 200-250 mg of iron.Thus, patients who arereceiving an average of 2 to 4 units of blood monthly willhave an iron intake of 5000to 10 000 mg of iron per year. Iron overload(IO) A condition in which the body takes up and stores more iron than it needs from any cause. Iron overload constitutes a major problem in patients receivingregular blood transfusion. Patients with β-thalassemia,sickle cell anemia, and congenital and refractory anemiasonchronic transfusion programs accumulate iron in variousbody organs. Untreated iron overload will eventually lead todamage of the liver, endocrine organs, and most seriously theheart(1).Acquired platelet function defect might be one of thecomplications of iron overload. This could occur indirectlythrough the effect of iron load on the liver and other organsor might occur due to effect of iron load on platelet functiondirectly. Dleteriouscomlications contributed by chemical reactive deregulated iron may affect cellular homeostasis systematically lead to tissue and organ damage when this toxicity occurred in blood cells ,alteration of peripheral hematological profile concerning erythrocyte,leucocyte and Platelet. On the other hand, acquired platelet function defects are classified broadly into defects that are intrinsic or extrinsic to the platelets. Acquired platelets defect are due to medications, medical conditions, underlying hematologic diseases, and are more frequent than inherited causes of platelets defects. (2) Platelet function is also influenced by changes in membranefluidity that has an important role in the expressionof platelet receptors and in modulating the activity ofproteins like phospholipase C or proteinkinase C(3). Ithas been shown (4) that changes in membrane fluidityare associated to altered aggregation/agglutination functionof freshly prepared platelets. The platelet aggregationresponse is modified by monovalent cations (whichalter fibrinogen binding) and monovalent anions thatenhance hydroxyl radicals production of platelets inducing platelet activation (5) Reactive oxygen species(ROS) are involved in integrin aIIbb3 activation(6,7). Moreover, bursts of ROS are generated in platelets exposed to thrombin (8). We herein report the case of a patient with acquired plateletfunction defect associated with iron overload as a consequenceof chronic blood transfusion. Therefore, we emphasizethe necessity of further studies to confirm directcorrelation between iron overload as a causative agent andplatelets dysfunction. And we recommend screening forplatelet function in patients receiving chronic blood transfusionaiming at possible prevention of any lifethreateningbleeding.

One of the most commonly used laboratorymarkers to early characterize platelet functionis the mean platelet volume (MPV). Increasedplatelet volume mayindicate its greater content ingranules, showing a platelet activation also betteraggregation and more reactive than the ordinarysize one. Limited study and the inconsistent resultare available regarding the platelet function studyin IO complicated condition. Higher MPV wasidentified in heterozygous beta-thalassemiapatientswith no correlation with cardiovascularrelatedrisks( 9). However, but in line with this study, adefect in platelet aggregation indicated by ahyporeactivityof platelet after induction withADP, ristocetin, and collagen was showed in majorthalassemia children patients