Date Published: July 19, 2017
Publisher: Public Library of Science
Author(s): Wondemagegn Mulu, Bayeh Abera, Zewdie Mekonnen, Yesuf Adem, Mulat Yimer, Yohannes Zenebe, Asmare Amuamuta, Wondimu Gebeyehu, Suresh kumar Subbiah.
Establishing national population haematological and immunological reference ranges are essential for clinical management of patients. However, there is scarcity of information on community based haematological reference ranges established from Ethiopian population. Therefore, this study aimed at determining haematological and CD4+ T cells reference ranges in healthy adults from East and West Gojjam zones, Ethiopia.
Community based cross-sectional study was conducted from May 2015 to December 2015 in healthy adult residents of Gojjam zone. A total of 481(246 females and 235 males) healthy adults enrolled in the study. Healthy adults were defined by medical history, physical examination and laboratory screening for HIV, HBV, HCV and intestinal parasitosis. Haematological parameters were measured using haematology analyzer MindrayBC320 (Mindray Biomedical electronic Corporation, China). CD4+Tcells were enumerated using FACS count (Becton Dickinson).
The median age of the participants was 25 years. The overall median and 95th percentile of CD4+ T cells count were 869 cells/mm3 and396–1598 cells/mm3, respectively. Females had a significantly higher CD4+ T cell counts compared to males (P = 0.002). The 95th percentile range for red blood cells (RBCs) was 3.93–6.1 x 106cells/mm3and for hematocrit (Hct) was 40–58% while for hemoglobin (Hb) was 15.69–17.84g/dl. Males had significantly higher values of RBC and Hct than females (P < 0.001). Females (120–379 x 106 cells/mm3) had significantly higher platelet counts than males (106–352 x106 cells/mm3) (P < 0.001). The overall median of WBC was6.78 x103/mm3and its95thpercentile range was3.5–11.5 x103/mm3. The overall 95th percentile range of MCV, MCH and MCHC were 89.5–107.5 fl, 28–34 pg and 30–33.2g/dl, respectively. The higher mean absolute count of RBCs was found in the youngest age groups (P = 0.03). The mean count of RBCs and Hct were significantly higher in highschool completed and above than other participants (P < 0.001). The lower and upper limit of platelet counts was significantly higher in highland (118 -383x106 cells/mm3) compared to lowland residents (107–352 x106 cells/mm3) (P < 0.001). Moreover, it was significantly higher in residents with better monthly income (124–383 x106 cells/mm3) compared to the counters (115–368 x106 cells/mm3) (P = 0.02). Some of the haematological and CD4+ T cells reference ranges of the healthy adults in this study showed variations with the reference ranges used and reported so far in Ethiopia, Africa and Western countries. We recommend further study considering gender, altitude, and residency in other parts of Ethiopia to establish national reference ranges for Ethiopian population.
Health and disease can only be distinguished by accurate and reliable reference ranges of a particular test . Haematological and CD4+ T cells reference ranges are useful both in the clinical and research areas . They are primarily used for accurate interpretation of laboratory results, identifying abnormal laboratory results, guiding patient diagnosis and clinical managements . Reference ranges are essential to screen physiological or pathological conditions and monitor patho-physiological changes after infection or disease states, or following the administration of drugs in therapeutic or clinical interventions and vaccine studies .
In Ethiopia diagnostic and treatment health facilities employed haematological reference ranges adopted from western countries. At the same time there is no uniform usage of a hematological parameters reference ranges at the national level. Health care providers may obtain these reference ranges from pocket and text books, WHO reports, browsing internet and inserts from kits to compare the reported values. A variety of inserted kits are also available from several companies as a result of different health facilities uses various types of automated machines such as Mindray, Cell-DYn 1800, Sysmex (Xs-500i) and Cell-DYN Rubey. In spite of these, limited studies on haematological reference ranges have been reported among apparently healthy individuals attending hospitals either for blood donation, HIV counseling and testing [5, 14]. Therefore, this study presents community based haematological reference ranges in healthy adults of Ethiopia and may be a baseline for Federal Ministry of Health for future national reference range establishment.
Some of the haematological and CD4+T cells reference ranges of healthy adults in Gojjam showed variations with reference ranges used in the study community, reported in Africa, Western countries and Wintrobes standard. Difference in altitude and gender significantly affects the reference intervals. Therefore, considering gender, altitude and residency further studies in other parts of Ethiopia are recommended to establish reference intervals for Ethiopian population.