Immature reticulocyte fraction is an early predictor of bone marrow recovery post chemotherapy in patients with acute leukemia

ABSTRACT

To establish the benefits of immature reticulocyte fraction [IRF] measurement using an automated hematology cells analyzer over absolute neutrophil count [ANC] in predicting bone marrow recovery post induction chemotherapy. A prospective observational study was carried out in the Departments of Pathology, Medicine, and Pediatrics, Universiti Kebangsaan Malaysia, Medical Center [UKMMC], Kuala Lumpur, Malaysia during a period of 19 months from April 2009 to December 2010 to assess the bone marrow recovery in patients with acute leukemia. A total of 22 patients in remission induction phases were enrolled in this study. The blood specimens were collected from day zero after chemotherapy, and every 3 days until patients recovered hematologically. All blood samples were measured for ANC and IRF using an automated hematology analyzer [Beckman-Coulter LH750]. The percentage of patients showing IRF recovery earlier than ANC recovery was 63.6% [14 out of 22 patients]. There was a significant difference in the mean number of days for IRF recovery as compared with ANC recovery [14.05 and 17.18 days], p=0.005. This study proved that IRF was more useful in predicting bone marrow recovery in a patient with acute leukemia post induction chemotherapy compared with ANC. The IRF is not affected by infection, is easily measured, and inexpensive; thus, it is a reliable parameter to evaluate bone marrow reconstitution