Establishing Reference Ranges of Hematological Parameters from Malian Healthy Adults

Normal Clinical Laboratory Ranges by Age and Sex, and Impact on Study Screening Outcomes in Rural Mali

The interpretation of a laboratory test result requires an appropriate reference range established in healthy subjects, and normal ranges may vary by factors such as geographic region, sex, and age. We examined hematological and clinical chemistry parameters in healthy residents at two rural vaccine trial sites: Bancoumana and Doneguebougou in Mali, West Africa. During screening of clinical studies in 2018 and 2019, peripheral blood samples from 1,192 apparently healthy individuals age 6 months to 82 years were analyzed at a laboratory accredited by the College of American Pathologists for a complete blood count, and creatinine and/or alanine aminotransferase levels. Based on manufacturers' reference range values, which are currently used in Malian clinical laboratories, abnormal values were common in this healthy population. In fact, 30.4% of adult participants had abnormal neutrophil levels and 19.8% had abnormal hemoglobin levels. Differences by sex were observed in those who were older, but not in those younger than 10 years, for several parameters, including hemoglobin, platelet, and absolute neutrophil counts in hematology, and creatinine in biochemistry. The site-specific reference intervals we report can be used in malaria vaccine clinical trials and other interventional studies, as well as in routine clinical care, to identify abnormalities in hematological and biochemical parameters among healthy Malian trial participants.

Evidence of HIV-1 Genital Shedding after One Year of Antiretroviral Therapy in Females Recently Diagnosed in Bamako, Mali

Little is known about the dynamic of HIV-1 shedding and resistance profiles in the female genital reservoir after antiretroviral therapy (ART) initiation in resource-limited countries (RLCs), which is critical for evaluating the residual sexual HIV-1 transmission risk. The present study aimed to evaluate the efficacy of 1 year duration ART at blood and genital levels in females newly diagnosed for HIV-1 from three centers in Bamako, Mali. Seventy-eight consenting females were enrolled at the time of their HIV-1 infection diagnosis. HIV-1 RNA loads (Abbott Real-Time HIV-1 assay) were tested in blood and cervicovaginal fluids (CVF) before and 12 months after ART initiation. Primary and acquired resistances to ART were evaluated by Viroseq^TM HIV-1 genotyping assay. The vaginal microbiota was analyzed using IonTorrent^TM NGS technology (Thermo Fisher Scientific). Proportions of primary drug resistance mutations in blood and CVF were 13.4% and 25%, respectively. Discrepant profiles were observed in 25% of paired blood/CVF samples. The acquired resistance rate was 3.1% in blood. At month 12, undetectable HIV-1 RNA load was reached in 84.6% and 75% of blood and CVF samples, respectively. A vaginal dysbiosis was associated with HIV RNA shedding. Our findings emphasize the need of reinforcing education to improve retention in care system, as well as the necessity of regular virological monitoring before and during ART and of implementing vaginal dysbiosis diagnosis and treatment in RLCs.

Hematological and CD4+ T- cell count reference interval for pregnant women attending antenatal care at Hawassa University Comprehensive Specialized Hospital, Hawassa Southern Ethiopia

BACKGROUND

Pregnancy is a state characterized by physiological, hematological, and immunological changes. However, the reference intervals (RI) being used in clinical practice in Ethiopia are derived from non-local general populations. Therefore; this study was aimed to determine the reference interval of hematological and immunological profiles among healthy pregnant mothers attending Hawassa University Hospital.

METHODS

A cross-sectional study in a total of 360 healthy pregnant women was enrolled from January to April 2019, at Hawassa University hospital. Sociodemographic and obstetric data were collected using a structured questionnaire. Blood samples collected from each participant were used to define the hematological parameters. The median and 95% intervals were calculated for the immunological and hematological profiles. P-value 0.05 was considered statistically significant.

RESULT

A total of 360 healthy pregnant women were enrolled in this study. The age range of the participants was 18-45 years. 342(95%) were married and 270 (75%) of the participants were multigravida. The overall median CD4+ T-cell and total WBC counts (cells/mm3) were 602 and 7.58 respectively. The overall median value for lymphocytes, neutrophils, monocytes, eosinophils, and basophil count was (cells/mm3) was 2.21, 6.74, .63, .53, and 0.09 respectively. Whereas the median RBC and platelet count was 4.48×106/μLand 212×106/μL. The median value of hematological profiles in the first, second, and third trimesters was TWBC (103/μL) (7.90, 8.30, 8.65), RBC (106/μL) (4.5, 4.6, 4.62), and PLT (103/μL) (210, 209,161) respectively. The CD4 T cell count median value was (600, 598, and 591) in the first, second, and third trimesters. Significant changes were observed in hematological and immunological parameters between trimesters (P < 0.05).

CONCLUSION

Significant changes were observed in hematological and immunological parameters between trimesters (P < 0.05). Considerable differences were also seen between the values in this study and other studies from Ethiopia and other countries, indicated the need for the development of local reference intervals for pregnant women.

Hematological reference intervals for adult population of Dire Dawa town, East Ethiopia

Background

Reference interval (RI) for hematological parameters is used to interpret laboratory test results in the diagnosis, management and monitoring of hematologic disorders. Several factors including sex, age, dietary patterns, pregnancy status, ethnicity and geographic location affect hematological RIs. However, manufacturers derived reference value is currently in use in most developing countries including Ethiopia. This study aimed to establish hematological RIs for adult population living in Dire Dawa town, East Ethiopia.

Methods

In this cross-sectional study, 513 apparently healthy adults of Dire Dawa town were enrolled from January to March 2019. From these, 342 (171 males and 171 non-pregnant females) were aged 18–65 years while 171 were pregnant women aged 15–49 years. After obtaining written informed consent, 5ml fresh whole blood was collected of which 2ml was used for hematologic analysis using Mindray BC-3000plus hematology analyzer and 3ml for serological tests. The 2.5^th and 97.5^th RI was computed by non-parametric test employing SPSS version 24. P-value <0.05 was considered statistically significant.

Result

Males had significantly higher reference value for most of red cell parameters (Hgb, RBC, HCT, MCH and MCHC) than females (p <0.05), while most of the WBC parameters were significantly higher in females than males. Moreover, non-pregnant women had higher values for most of red cell parameters than pregnant women. Pregnant women had higher WBC parameters than their non-pregnant counterparts.

Conclusion

The hematologic RIs obtained in this study shows variation between genders, between pregnant and non-pregnant women, from the clinical practice currently utilised in Dire Dawa town and from studies conducted in Ethiopia, African countries as well as the Western population. It underscores the need for utilising gender and pregnancy specific, locally derived hematologic RI for better management, diagnosis and monitoring of hematologic disorders for adults of both genders and pregnant women.

Partnership for Research on Ebola VACcination (PREVAC): protocol of a randomized, double-blind, placebo-controlled phase 2 clinical trial evaluating three vaccine strategies against Ebola in healthy volunteers in four West African countries

Introduction

The Ebola virus disease (EVD) outbreak in 2014–2016 in West Africa was the largest on record and provided an opportunity for large clinical trials and accelerated efforts to develop an effective and safe preventative vaccine. Multiple questions regarding the safety, immunogenicity, and efficacy of EVD vaccines remain unanswered. To address these gaps in the evidence base, the Partnership for Research on Ebola Vaccines (PREVAC) trial was designed. This paper describes the design, methods, and baseline results of the PREVAC trial and discusses challenges that led to different protocol amendments.

Methods

This is a randomized, double-blind, placebo-controlled phase 2 clinical trial of three vaccine strategies against the Ebola virus in healthy volunteers 1 year of age and above. The three vaccine strategies being studied are the rVSVΔG-ZEBOV-GP vaccine, with and without a booster dose at 56 days, and the Ad26.ZEBOV,MVA-FN-Filo vaccine regimen with Ad26.ZEBOV given as the first dose and the MVA-FN-Filo vaccination given 56 days later. There have been 4 versions of the protocol with those enrolled in Version 4.0 comprising the primary analysis cohort. The primary endpoint is based on the antibody titer against the Ebola virus surface glycoprotein measured 12 months following the final injection.

Results

From April 2017 to December 2018, a total of 5002 volunteers were screened and 4789 enrolled. Participants were enrolled at 6 sites in four countries (Guinea, Liberia, Sierra Leone, and Mali). Of the 4789 participants, 2560 (53%) were adults and 2229 (47%) were children. Those < 18 years of age included 549 (12%) aged 1 to 4 years, 750 (16%) 5 to 11 years, and 930 (19%) aged 12–17 years. At baseline, the median (25th, 75th percentile) antibody titer to Ebola virus glycoprotein for 1090 participants was 72 (50, 116) EU/mL.

Discussion

The PREVAC trial is evaluating—placebo-controlled—two promising Ebola candidate vaccines in advanced stages of development. The results will address unanswered questions related to short- and long-term safety and immunogenicity for three vaccine strategies in adults and children.

Trial registration

ClinicalTrials.gov NCT02876328. Registered on 23 August 2016.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05035-9.

Adult and paediatric haematology and clinical chemistry laboratory reference limits for Liberia

Background

As more research is conducted in Liberia, there is a need for laboratory reference limits for common chemistry and haematology values based on a healthy population. Reference limits from the United States may not be applicable.

Objective

The aim of this study was to present laboratory reference ranges from a Liberian population and compare them to United States ranges.

Methods

Serum chemistry and haematology values from 2529 adults and 694 children and adolescents obtained from two studies conducted in Liberia between 2015 to 2017 were used to determine reference limits. After removing outliers, the reference limits defined by the 2.5th and 97.5th percentiles were determined by sex in three age groups (6–11, 12–17, and 18+ years).

Results

The median (interquartile range) of adults was 29 (23, 37) years; 44% were female. The median (interquartile range) for children and adolescents was 12 (9, 15) years; 53% were female. Several reference ranges determined using Liberian participants differed from those in the US. For chemistries, a high percentage of both adults and children/adolescents had high serum chloride levels based on United States ranges. For haematology, a high percentage of Liberian participants had haemoglobin and related assays below the lower limit of United States ranges.

Conclusion

Chemistry and haematology reference intervals determined for a Liberian population of healthy individuals should be considered for establishing eligibility criteria and monitoring of laboratory adverse events for clinical trials as well as for use in clinical settings in Liberia and perhaps for other countries in Western Africa.

Haematological and Biochemical Reference Values for Healthy Population of Maferinyah Rural Community in Guinea

Guinea's reference ranges for biological parameters rely on those of Caucasian values. Variability in reference ranges according to the context is well-documented. We conducted this study for the purpose of future malaria clinical trials that assess the efficacy and safety of malaria drugs. A repeated cross-sectional study was carried out, in an apparently healthy cohort population. Surveys took place in Maferinyah rural community, which is located at 75 km from the capital. The 2.5^th and 97.5^th percentiles were determined nonparametrically and stood for reference intervals. Reference values were determined separately for males and females according to ranges of age (6-10 years of age; 11-15 years of age; 16-45 years of age). Differences between genders were tested using the Mann-Whitney test, while the Friedman test was performed to test differences within each gender group according to the seasons. A total of 450 volunteers were enrolled. The median age was 13. Males 16-45 years of age had significantly higher hematologic and biochemical values compared to a female of the same age (for hematological parameters: Mean Cell Hemoglobin Concentration MCHC p ≤ 0.001, Platelets p ≤ 0.001, monocytes p = 0.0305, eosinophils p = 0.0225; for biochemical parameters: Aspartate aminotransferase AST p ≤ 0.001, Alanine Aminotransferase ALT p ≤ 0.001, creatinine p ≤ 0.001). We noticed significant seasonal variations for all the biochemical parameters and some hematologic parameters (Mean Corpuscular Hemoglobin MCH, MCHC, Mean Cell volume). This is the first study establishing hematologic and biochemical parameters in Guinea. These findings provide a useful guide for the clinical researchers and care providers. Studies on large scale and in different settings would be also desirable.

Association of environmental exposure with hematological and oxidative stress alteration in gasoline station attendants

Gasoline station attendants spend a great deal of their time in the direct exposure to noxious substances such as benzene and byproducts of gasoline combustion. Such occupational exposure increases the risk of oxidative stress. This study aimed to evaluate hematological and biochemical alterations among petrol station workers. Forty gas station attendants and 39 non-attendants were recruited as exposed and control subjects, respectively. Plasma samples were evaluated for hemoglobin, hematocrit, and red blood cell count via the Sysmex KX-21 analyzer. Then, oxidized hemoglobin, methemoglobin, and hemichrome were measured spectrophotometrically. Moreover, serum antioxidant capacity and protein oxidation were evaluated. The means ± SD of hemoglobin (16.76 ± 0.14 g/dl vs 15.25 ± 0.14 g/dl), hematocrit (49.11 ± 0.36% vs 45.37 ± 0.31%), RBC count (5.85 ± 0.06 mil/μl vs 5.33 ± 0.06 mil/μl), Met-HB (1.07 ± 0.07 g/dl vs 0.39 ± 0.04 g/dl), and hemichrome (0.80 ± 0.07 g/dl vs 0.37 ± 0.02 g/dl) in the exposed group were significantly greater than the control group (P < 0.001). The results of the independent-sample t test illustrated that the FRAP test value in the exposed group (0.23 ± 0.01 mM) was significantly lower than the control group (0.34 ± 0.01 mM), while the value of the plasma protein carbonyl test in the exposed group (7.47 ± 0.33 mmol/mg protein) was meaningfully greater than the control group (5.81 ± 0.19 mmol/mg protein) (P < 0.001). In conclusion, gas station attendants suffer from higher levels of oxidative stress, and they need to take antioxidants in order to minimize the effects of oxidative stress.

[Distribution of peripheral blood lymphocyte subsets in 826 healthy children aged 0-6 years]

OBJECTIVE

To study the distribution of peripheral blood lymphocyte subsets in healthy children aged 0-6 years.

METHODS

A total of 826 healthy Han children aged 0-6 years were recruited. According to their age, the children were divided into four groups: newborn, infant, toddler and preschool. Their peripheral blood samples were collected to measure the percentages of lymphocyte subsets by flow cytometry.

RESULTS

There were significant differences in the percentages of CD3⁺ T cells, CD3⁺CD4⁺ T cells and CD3^-CD19⁺ B cells and the CD4⁺/CD8⁺ ratio between boys and girls (P<0.05). The girls had a lower percentage of CD3^-CD19⁺ B cells, higher percentages of CD3⁺ T cells and CD3⁺CD4⁺ T cells and a higher CD4⁺/CD8⁺ ratio than the boys. The newborn group had the highest percentages of CD3⁺ T cells and CD3⁺CD4⁺ T cells and the highest CD4⁺/CD8⁺ ratio (P<0.05). The percentage of CD3⁺CD4⁺ T cells and the CD4⁺/CD8⁺ ratio gradually decreased with age and the preschool group had the lowest values (P<0.05). The newborn group had the lowest percentages of CD3^-CD19⁺ B cells and CD3^-CD16⁺CD56⁺ NK cells (P<0.05). The percentage of CD3^-CD16⁺CD56⁺ NK cells gradually increased with age and the preschool group had the highest percentage (P<0.05). The percentage of CD3^-CD19⁺ B cells reached the peak in the toddler period and then decreased with age (P<0.05). The preschool group had the highest percentage of CD3⁺CD8⁺ T cells (P<0.05). The variation trend of distribution of lymphocyte subsets in boys from different age groups was consistent with that in children from different age groups. For girls, the newborn group had the highest percentage of CD3⁺CD4⁺ T cells and CD4⁺/CD8⁺ ratio (P<0.05).

CONCLUSIONS

The distribution of peripheral blood lymphocyte subsets in healthy children is significantly different across ages and sexes. Therefore, the reference values should be established according to age and sex.

[Distribution of peripheral blood lymphocyte subsets in 826 healthy children aged 0-6 years]

OBJECTIVE

To study the distribution of peripheral blood lymphocyte subsets in healthy children aged 0-6 years.

METHODS

A total of 826 healthy Han children aged 0-6 years were recruited. According to their age, the children were divided into four groups: newborn, infant, toddler and preschool. Their peripheral blood samples were collected to measure the percentages of lymphocyte subsets by flow cytometry.

RESULTS

There were significant differences in the percentages of CD3+ T cells, CD3+CD4+ T cells and CD3-CD19+ B cells and the CD4+/CD8+ ratio between boys and girls (P<0.05). The girls had a lower percentage of CD3-CD19+ B cells, higher percentages of CD3+ T cells and CD3+CD4+ T cells and a higher CD4+/CD8+ ratio than the boys. The newborn group had the highest percentages of CD3+ T cells and CD3+CD4+ T cells and the highest CD4+/CD8+ ratio (P<0.05). The percentage of CD3+CD4+ T cells and the CD4+/CD8+ ratio gradually decreased with age and the preschool group had the lowest values (P<0.05). The newborn group had the lowest percentages of CD3-CD19+ B cells and CD3-CD16+CD56+ NK cells (P<0.05). The percentage of CD3-CD16+CD56+ NK cells gradually increased with age and the preschool group had the highest percentage (P<0.05). The percentage of CD3-CD19+ B cells reached the peak in the toddler period and then decreased with age (P<0.05). The preschool group had the highest percentage of CD3+CD8+ T cells (P<0.05). The variation trend of distribution of lymphocyte subsets in boys from different age groups was consistent with that in children from different age groups. For girls, the newborn group had the highest percentage of CD3+CD4+ T cells and CD4+/CD8+ ratio (P<0.05).

CONCLUSIONS

The distribution of peripheral blood lymphocyte subsets in healthy children is significantly different across ages and sexes. Therefore, the reference values should be established according to age and sex.

Mycobacterium africanum (Lineage 6) shows slower sputum smear conversion on tuberculosis treatment than Mycobacterium tuberculosis (Lineage 4) in Bamako, Mali

Objective

Ancestral M. tuberculosis complex lineages such as M. africanum are underrepresented among retreatment patients and those with drug resistance. To test the hypothesis that they respond faster to TB treatment, we determined the rate of smear conversion of new pulmonary tuberculosis patients in Bamako, Mali by the main MTBc lineages.

Methods

Between 2015 and 2017, we conducted a prospective cohort study of new smear positive pulmonary tuberculosis patients in Bamako. Confirmed MTBc isolates underwent genotyping by spoligotyping for lineage classification. Patients were followed at 1 month (M), 2M and 5M to measure smear conversion in auramine (AR) and Fluorescein DiAcetate (FDA) vital stain microscopy.

Result

All the first six human MTBc lineages were represented in the population, plus M. bovis in 0.8% of the patients. The most widely represented lineage was the modern Euro-American lineage (L) 4, 57%, predominantly the T family, followed by L6 (M. africanum type 2) in 22.9%. Ancestral lineages 1, 5, 6 and M. bovis combined amounted to 28.8%. Excluding 25 patients with rifampicin resistance, smear conversion, both by AR and FDA, occurred later in L6 compared to L4 (HR 0.80 (95% CI 0.66–0.97) for AR, and HR 0.81 (95%CI 0.68–0.97) for FDA). In addition we found that HIV negative status, higher BMI at day 0, and patients with smear grade at baseline ≤ 1+ were associated with earlier smear conversion.

Conclusion

The six major human lineages of the MTBc all circulate in Bamako. Counter to our hypothesis, we found that patients diseased with modern M. tuberculosis complex L4 respond faster to TB treatment than those with M. africanum L6.

Reference intervals for hematology test parameters from apparently healthy individuals in southwest Ethiopia

BACKGROUND

Clinical laboratory reference intervals are an important tool to identify abnormal laboratory test results. The generating of hematological parameters reference intervals for local population is very crucial to improve quality of health care, which otherwise may lead to unnecessary expenditure or denying care for the needy. There are no well-established reference intervals for hematological parameters in southwest Ethiopia.

OBJECTIVE

To generate hematological parameters reference intervals for apparently healthy individuals in southwest Ethiopia.

METHODS

A community-based cross-sectional study was conducted involving 883 individuals from March to May 2017. Four milliliter of blood sample was collected and transported to Jimma University Medical Center Laboratory for hematological analysis and screening tests. A hematological parameters were measured by Sysmex XS-500i hematology analyzer (Sysmex Corporation Kobe, Japan). The data were analyzed by SPSS version 20 statistical software. The non-parametric independent Kruskal-Wallis test and Wilcoxon rank-sum test (Mann-Whitney U test) were used to compare the parameters between age groups and genders. The 97.5 percentile and 2.5 percentile were the upper and lower reference limit for the population.

RESULTS

The reference interval of red blood cell, white blood cell, and platelet count in children were 4.99 × 1012/L (4.26-5.99 × 1012/L), 7.04 × 109/L (4.00-11.67 × 109/L), and 324.00 × 109/L (188.00-463.50 × 109/L), respectively. The reference interval of red blood cell, white blood cell, and platelet count in adults was 5.19 × 1012/L (4.08-6.33 × 1012/L), 6.35 × 109/L (3.28-11.22 × 109/L), and 282.00 × 109/L (172.50-415.25 × 109/L), respectively. The reference interval of red blood cell, white blood cell, and platelet count in geriatrics were 5.02 × 1012/L (4.21-5.87 × 1012/L), 6.21 × 109/L (3.33-10.03 × 109/L), and 265.50 × 109/L (165.53-418.80 × 109/L), respectively. Most of the hematological parameters showed significant differences across all age groups.

CONCLUSION

Most of the hematological parameters in this study showed differences from similar studies done in the country. This study provided population-specific hematological reference interval for southwest Ethiopians. Reference intervals should also be established in the other regions of the country.

Prevalence of Low Platelet Count and Identification of Associating Determinants and Genetic Polymorphism in Healthy Individuals of Upper Assam, India

The purpose of the study was to assess the prevalence of low platelet count among the healthy population of upper Assam, India. The impact of socio-demographic features was moreover pointed to evaluate. Additionally, Mean platelet volume (MPV) and Interleukin-6 gene polymorphism (-174 G > C) were also determined to speculate their effect on the basal platelet count. For determination of hematological indices, CBC was done and genetic polymorphism was identified by ARMS-PCR technique. Out of 510 study subjects, 25.3% (n = 129) had low platelet count, and females were recorded with significantly higher mean platelet count as compared to their male counterpart (p < 0.001). A progressive decline in platelet count was observed with ageing and more significantly noticed in females across the various age groups (p < 0.001). The mean MPV was significantly higher in low platelet count group as compared to the normal group (p < 0.001). Both platelet count and MPV differed significantly among the individuals with varied ethnicity. An inverse correlation between platelet count and its volume was reported, and such observation was continued to persist in every age-group under the study. However, no significant differences were observed for other hematological indices between the studied groups except for platelet indices and RBC count. Moreover, the peripheral blood smear examined for cellular morphology and in vitro platelet clumping did not report any significant aberrancy. No significant penetrance of the risk allele was revealed in the studied groups. However, ARMS-PCR confirmed 6% (n = 8/129) of the low platelet count subjects with heterozygous for G allele. This happens to be the first description of low platelet count among the healthy population of upper Assam, where age, gender, ethnicity, and MPV are significantly associated with platelet count variation. Heterozygosity of the risk allele does not contribute to the low platelet count condition.