Platelets newly released from the bone marrow are larger and more reactive than mature and contain larger amounts of RNA.Due to their similarity with reticulocytes, they are called reticulated (RP) or immature platelets (IP). 1 It was long believed that this RNA was a vestigial remnant of megakaryocytic RNA, but more recent studies indicate that platelets can use this RNA for protein synthesis. 2,3 The number of RP in the bone marrow, on average 2-to 3-fold that in the peripheral blood, is correlated with the number of megakaryocytes. While in normal conditions, "mature" platelets persist in the circulation for about 7-10 days, 4 RP appear to remain in the blood stream for 24-36 hours, during which time a progressive degradation of RNA and a decrease in volume take place. 5,6 Furthermore, as the number of RP is related to thrombopoiesis, increasing with increased production and decreasing when production decreases, they can act as real-time markers of megakaryopoiesis.

The use of these two parameters is useful to detect iron deficiency conditions if the hemoglobin synthesis has already been compromised.

When compared with XE-5000, BC-6800 shows a good overall correlation on counting despite evidence of difference in the upper limit of reference intervals (93.2 vs 101.3). Comparison of diagnostic efficiency of extended parameters shows a good total agreement of RHE (91.6%).

In view of their effect on MPV and other related indices, the preanalytical and analytical variables make them, little more than experimental.