Changes in Bone Marrow Hematopoiesis in Victims With Burn Injury Depending on the Clinical Outcome

Burn injury remains an extremely pressing problem of modern healthcare worldwide, due to its high frequency, as well as high mortality and disability of victims. The development of persistent anemia after a burn is one of the most common complications affecting both the course of burn disease and the final clinical outcome. The study included 23 male victims aged 33 (24-47) years, admitted to hospital on the 2 (1-3) day after the burn. The victims were divided into two groups depending on the final clinical outcome. The 1st group included 12 survivors, aged 33 (25-38)years, total area of burns (TBSA) 27 (17-39)%, area of deep burns 9.2 (0-16)%, APACHE II 6,5 (5-7) points, Franc index (FI) 47 (30-62) points. The 2nd group included 11 dead victims, age 26 (23-43) years, total area of burns 57 (45-71)%, TBSA 32 (22-35)%, APACHE II 24,3 (21,5-28) points, FI 137(129-175) points. All patients underwent clinical blood analysis to determine the number of erythrocytes and hemoglobin concentration upon admission to the hospital. To assess disorders in the erythroid lineage, a microscopic examination of bone marrow punctate obtained by sternal puncture was performed with subsequent calculation of the following parameters: total cytosis, erythroblasts, basophilic normoblasts (BNB), polychromatophilic normoblasts (PNB), oxyphilic normoblasts (ONB). The median (Me) and interquartile range (IQR) were calculated for each indicator. A comparative analysis of the number of erythrocytes and hemoglobin concentration in the peripheral blood, as well as the number of erythroid lineage cells in the bone marrow punctate, was performed in the victims of the two groups. The reliability of differences between the studied samples was determined using the Mann-Whitney U-test (p < 0.05). It was found that fatal victims, compared to survivors, had a reduced number of erythrocytes and hemoglobin concentration in the peripheral blood, as well as reduced cytosis (30 (29-58) and 103 (85-237), × 109/ l), the number of BNB (0.15 (0,13-0,2) and 0.95 (0,34-1,4), × 109/l) and PNB (2,4 (1,5-2,8) and 14,6 (6,9-22,2), × 109/l) (p < 0.05). To assess the relationship between the severity of burn injury and the studied erythropoiesis indices, a correlation analysis (Spearman coefficient) was performed. A correlation was found between bone marrow cytosis and FI (r= -0,72), TBSA (r= -0,77), APACHE II (r= -0,61), and the area of deep burns (r= -0,68). For PNB, a relationship was shown with FI (r= -0,85), TBSA (r= -0,89), the area of deep burns (r= -0,85), and APACHE II (r= -0,72). Low bone marrow cytosis, as well as a decrease in the number of BNB, PNB on days 1-3 after a burn injury can be used as markers of an unfavorable outcome of burn disease. Using the ROC analysis method, cut-off points were calculated for cytosis (58,5×109/l), BNB (0,292×109/l), and RNB (11,597×109/l), which have high sensitivity and specificity for predicting an unfavorable outcome. The presence of a relationship between bone marrow cytosis, the number of PNB with FI, APACHE II, TBSA, and the area of deep burns reflects the possibility of using these indicators of bone marrow hematopoiesis to assess the severity of a burn injury and the condition of the victim.