Adult Hematology and Clinical Chemistry Laboratory Reference Ranges in a Zimbabwean Population.
BACKGROUND
Laboratory reference ranges used for clinical care and clinical trials in various laboratories in Zimbabwe were derived from textbooks and research studies conducted more than ten years ago. Periodic verification of these ranges is essential to track changes over time. The purpose of this study was to establish hematology and chemistry laboratory reference ranges using more rigorous methods.


METHODS
A community-based cross-sectional study was carried out in Harare, Chitungwiza, and Mutoko. A multistage sampling technique was used. Samples were transported from the field for analysis at the ISO15189 certified University of Zimbabwe-University of California San Francisco Central Research Laboratory. Hematology and clinical chemistry reference ranges lower and upper reference limits were estimated at the 2.5th and 97.5th percentiles respectively.


RESULTS
A total of 769 adults (54% males) aged 18 to 55 years were included in the analysis. Median age was 28 [IQR: 23-35] years. Males had significantly higher red cell counts, hemoglobin, hematocrit, and mean corpuscular hemoglobin compared to females. Females had higher white cell counts, platelets, absolute neutrophil counts, and absolute lymphocyte counts compared to males. There were no gender differences in eosinophils, monocytes, and absolute basophil count. Males had significantly higher levels of urea, sodium, potassium, calcium, creatinine, amylase, total protein, albumin and liver enzymes levels compared to females. Females had higher cholesterol and lipase compared with males. There are notable differences in the white cell counts, neutrophils, cholesterol, and creatinine kinase when compared with the currently used reference ranges.


CONCLUSIONS
Data from this study provides new country specific reference ranges which should be immediately adopted for routine clinical care and accurate monitoring of adverse events in research studies.
University of Zimbabwe-University of California San Francisco Collaborative Research Programme, Harare, Zimbabwe.
Wadzanai P
http://orcid.org/0000-0003-0215-9309
WP
Samaneka
Department of Community Medicine, University of Zimbabwe College of Health Sciences, Harare, Zimbabwe.|University of Zimbabwe Clinical Research Centre, Harare, Zimbabwe.
Gibson
G
Mandozana
Department of Community Medicine, University of Zimbabwe College of Health Sciences, Harare, Zimbabwe.
Willard
W
Tinago
University of Zimbabwe-University of California San Francisco Collaborative Research Programme, Harare, Zimbabwe.
Nehemiah
N
Nhando
University of Zimbabwe-University of California San Francisco Collaborative Research Programme, Harare, Zimbabwe.
Nyaradzo M
NM
Mgodi
Department of Pediatrics, University of Zimbabwe College of Health Sciences, Harare, Zimbabwe.
Mutsawashe F
MF
Bwakura-Dangarembizi
University of Zimbabwe-University of California San Francisco Collaborative Research Programme, Harare, Zimbabwe.|Department of Obstetrics and Gynecology and Reproductive Health Sciences, University of Zimbabwe College of Health Sciences, Harare, Zimbabwe.
Marshall W
MW
Munjoma
Department of Chemical Pathology, University of Zimbabwe College of Health Sciences, Harare, Zimbabwe.
Zvenyika A R
ZA
Gomo
University of Zimbabwe-University of California San Francisco Collaborative Research Programme, Harare, Zimbabwe.|Department of Obstetrics and Gynecology and Reproductive Health Sciences, University of Zimbabwe College of Health Sciences, Harare, Zimbabwe.
Zvavahera M
ZM
Chirenje
University of Zimbabwe-University of California San Francisco Collaborative Research Programme, Harare, Zimbabwe.|Department of Medicine, University of Zimbabwe College of Health Sciences, Harare, Zimbabwe.|University of Zimbabwe Clinical Research Centre, Harare, Zimbabwe.
James G
JG
Hakim
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D019963:Clinical Chemistry Tests / Q000592:standards*; D005260:Female; D006405:Hematology / Q000592:standards*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D055815:Young Adult; D015030:Zimbabwe