Eliminating race-based reference ranges in haematology: a call to action.

In haematology, as in all of medicine, the use of reference intervals for laboratory variables is essential to define disease states and inform treatment decisions. There are many haematological variables, including haemoglobin, mean corpuscular volume, absolute neutrophil count, and iron indices, that are often reported to be different on the basis of a person's race or ethnicity. Although there are many haematological conditions with a genetic basis, such that it is appropriate to consider ancestry in the diagnostic algorithm, defining pathology on the basis of a social construct such as race is unacceptable. The inclusion of separate thresholds or simple statements that so-called normal values vary by race further validates the common misperception that there are physiological differences between Black and white patients. These statements might have downstream effects on diagnostic and treatment decisions that exacerbate existing racial health disparities. In this Viewpoint, we argued for the removal of race-based reference intervals across haematology.

Blood use in patients receiving intensive chemotherapy for acute leukemia or hematopoietic stem cell transplantation: the impact of a health system-wide patient blood management program.

BACKGROUND: Little is published on patient blood management (PBM) programs in hematology. In 2008 Western Australia announced a health system-wide PBM program with PBM staff appointments commencing in November 2009. Our aim was to assess the impact this program had on blood utilization and patient outcomes in intensive chemotherapy for acute leukemia or hematopoietic stem cell transplantation. STUDY DESIGN AND METHODS: A retrospective study of 695 admissions at two tertiary hospitals receiving intensive chemotherapy for acute leukemia or undergoing hematopoietic stem cell transplantation between July 2010 and December 2014 was conducted. Main outcomes included pre-red blood cell (RBC) transfusion hemoglobin (Hb) levels, single-unit RBC transfusions, number of RBC and platelet (PLT) units transfused per admission, subsequent day case transfusions, length of stay, serious bleeding, and in-hospital mortality. RESULTS: Over the study period, the mean RBC units transfused per admission decreased 39% from 6.1 to 3.7 (p < 0.001), and the mean PLT units transfused decreased 35% from 6.3 to 4.1 (p < 0.001), with mean RBC and PLT units transfused for follow-up day cases decreasing from 0.6 to 0.4 units (p < 0.001). Mean pre-RBC transfusion Hb level decreased from 8.0 to 6.8 g/dL (p < 0.001), and single-unit RBC transfusions increased 39% to 67% (p < 0.001). This reduction represents blood product cost savings of AU$694,886 (US$654,007). There were no significant changes in unadjusted or adjusted length of stay, serious bleeding events, or in-hospital mortality over the study. CONCLUSION: The health system-wide PBM program had a significant impact, reducing blood product use and costs without increased morbidity or mortality in patients receiving intensive chemotherapy for acute leukemia or hematopoietic stem cell transplantation.

A prospective pilot study comparing nasal blood sampling and venipuncture for the assessment of hemoglobin levels and INR.

OBJECTIVES/HYPOTHESIS: This study is a pilot study evaluating the feasibility of sampling nose blood during an emergency using a commercially available rapid test device. It also compares the accuracy of rapid nasal blood test results to the results of standard laboratory methods using venous blood sampling. METHODS: Nose blood was collected in patients suffering from active epistaxis. In an emergency setting, hemoglobin levels and the international normalized ratio (INR) were assessed using a rapid point-of-care test device. These results were compared to standard laboratory analyses from venous blood taken at the same time from the same patient. Twenty patients consented to and participated in these assessments. RESULTS: Linear regression comparing venous and nasal samples revealed strong correlations between the two methods for both hemoglobin and INR measurement. A Bland-Altman analysis showed the mean difference to be 2.3 g/L when comparing hemoglobin measurements made using the rapid point-of-care device to hemoglobin measurements made using conventional lab assessment. The corresponding mean difference for INR measurements was 0.14. CONCLUSION: The results of this pilot study support the use of point-of-care test devices using nasal blood sampling and provide preliminary data demonstrating that a rapid testing method can be reliable, practicable, and time-efficient. In our opinion, rapid hematologic screening for nasal and capillary blood should be available in emergency wards that treat epistaxis. LEVEL OF EVIDENCE: 4. Laryngoscope, 127:577-581, 2017.

[Current status of external quality assessment of fecal occult blood test].

BACKGROUND: Nationwide external quality assessment (EQA) of the fecal occult blood test (FOBT) in Korea was first introduced in 2007-2009. The EQA results were analyzed to assess the current status of FOBT and to plan the continuation of the EQA program. METHODS: The surveys included 40 hospitals in the preliminary survey conducted in 2007, 249 general hospitals in 2008, and 389 hospitals in 2009. In the surveys, the participating hospitals provided the results of the distributed materials and replies to the questionnaire on the FOBT test procedures and quality controls. RESULTS: In the surveys conducted between 2007 and 2009, a total of 650 institutes submitted 653 test system results; 3 institutes used 2 kinds of methods. All of the institutes used immunologic methods; 107 institutes (16.5%) used quantitative equipments and 546 institutes (84.0%) used qualitative kits. Most quantitative tests yielded consistent positive or negative results; however, their cut-off and measured values differed according to the equipments used. A low-level material tested in 2007 was negative in the quantitative methods but positive in some qualitative methods because of lower detection limits. The discordance rates among quantitative tests were 3.2% in 2007, 4.4% in 2008, and 0% in 2009 and the rates among qualitative tests were 13.8% in 2008 and 2.6% in 2009. Semi-solid EQA materials showed the ability to evaluate the overall test procedures with acceptable stability. CONCLUSIONS: In the first Korean FOBT EQA, commercially available EQA materials were proven to be stable. Continuation of the EQA program and further education of laboratory personnel are needed to reduce inconsistency in results. Further, the test kit, procedures, and result reports must be standardized.

International collaborative assessment study of the AHD575 method for the measurement of blood haemoglobin.

Accurate, economical methods for haemoglobin determination by laboratories in countries with limited resources are not available. This report provides the results of an international collaborative study evaluating the alkaline haematin detergent (AHD575) method as a reference method for laboratory services with limited resources. The study included 6 laboratories; 3 in East Mediterranean countries, 1 in East Africa and 3 in Europe. The (AHD575) method was evaluated against the HiCN method, with blood samples drawn from healthy and sick subjects. The results indicate that the AHD575 method is suitable for measuring haemoglobin in laboratories at all levels.

Normal ranges for packed cell volume and hemoglobin concentration in adults: relevance to 'apparent polycythemia'.

Published data from Europe and North America indicate that for non-iron-deficient adult Caucasian males, the normal mean packed cell volume (PCV) is 0.46 and the 2.5-97.5 percentile interval is 04.0-0.53. Corresponding values for adult Caucasian females are: mean PCV 0.42; 2.5-97.5 percentile interval 0.36-0.48. It is not usually appropriate to undertake studies of polycythemia in adult Caucasian males with PCV < 0.55 (Hb Conc. < 180 g/L) or in adult Caucasian females with PCV < 0.50 (Hb Conc. < 16.5 g/L). Application of this principle will reduce the number of inappropriate and costly studies that would otherwise be performed in patients whose PCV values are only in the upper percentiles of the normal range, and will help to avoid misdiagnoses and therapeutic misadventures.

Regression-based reference limits: determination of sufficient sample size.

Regression analysis is the method of choice for the production of covariate-dependent reference limits. There are currently no recommendations on what sample size should be used when regression-based reference limits and confidence intervals are calculated. In this study we used Monte Carlo simulation to study a reference sample group of 374 age-dependent hemoglobin values. From this sample, 5000 random subsamples, with replacement, were constructed with 10-220 observations per sample. Regression analysis was used to estimate age-dependent 95% reference intervals for hemoglobin concentrations and erythrocyte counts. The maximum difference between mean values of the root mean square error and original values for hemoglobin was 0.05 g/L when the sample size was > or = 60. The parameter estimators and width of reference intervals changed negligibly from the values calculated from the original sample regardless of what sample size was used. SDs and CVs for these factors changed rapidly up to a sample size of 30; after that changes were smaller. The largest and smallest absolute differences in root mean square error and width of reference interval between sample values and values calculated from the original sample were also evaluated. As expected, differences were largest in small sample sizes, and as sample size increased differences decreased. To obtain appropriate reference limits and confidence intervals, we propose the following scheme: (a) check whether the assumptions of regression analysis can be fulfilled with/without transformation of data; (b) check that the value of v, which describes how the covariate value is situated in relation to both the mean value and the spread of the covariate values, does not exceed 0.1 at minimum and maximum covariate positions; and (c) if steps 1 and 2 can be accepted, the reference limits with confidence intervals can be produced by regression analysis, and the minimum acceptable sample size will be approximately 70.