Immunohematological reference values for healthy adults in Burkina Faso.

Reference ranges for peripheral blood lymphocyte subsets were generated for 186 healthy adults in Burkina Faso using single-platform flow cytometry. CD4(+) T-cell counts ranged from 631 to 1,696 cells microl(-1); they were lower in males (n = 97) than in females (n = 89), whereas natural killer cell counts were higher.

Evaluation of a simplified dual-platform flow cytometric method for measurement of lymphocyte subsets and T-cell maturation phenotypes in the population of Nouna, Burkina Faso.

In the context of a larger clinical study in Nouna, Burkina Faso, we evaluated a simplified dual-platform (DP) flow cytometric (FCM) method that allows the determination of major lymphocyte subsets in a single test tube. We compared the phenotyping of lymphocytes with DP FCM and simultaneous measurements with standard single-platform (SP) FCM for samples from 177 individuals. Analysis of the comparative measurements revealed that DP FCM systematically underestimates the proportion of NK cells, overestimates the percentage of CD3(+) CD8(+) lymphocytes, and yields proportions of B cells and CD4(+) T cells comparable with the results from SP FCM. Bland-Altman analysis showed a low bias between both methods and an acceptable precision for percent values of CD4(+) T cells (bias +/- precision, -1% +/- 6%) and CD8(+) T cells (-3% +/- 6%). The absolute cell numbers of all lymphocyte subpopulations, however, were systematically biased towards lower values being obtained by DP FCM. Reference values for the distribution of T-cell maturation phenotypes in 177 healthy adults were calculated using DP FCM. The mean +/- standard deviation (SD) CD4(+)-to-CD8(+) T-cell ratio was 1.61 +/- 0.61, the mean percentage +/- SD of CD4(+) T cells was 42% +/- 7%, and that of CD8(+) T cells 29% +/- 7%. Among CD4(+) lymphocytes, 28% +/- 7% were classified as central memory (CD45RA(low) CCR7(+)), 22% +/- 10% as naïve (CD45RA(high) CCR7(+)), 45% +/- 12% as effector memory (CD45RA(low) CCR7(-)); and 5% +/- 3% as terminally differentiated effector memory expressing CD45RA (CD45RA(high) CCR7(-)). Among CD8(bright) lymphocytes, 3% +/- 2% had a central memory phenotype, 27% +/- 13% were naïve, 37% +/- 13% had an effector memory phenotype, and 34% +/- 12% were terminally differentiated effector memory cells expressing CD45RA.

Mortality patterns, 1993-98, in a rural area of Burkina Faso, West Africa, based on the Nouna demographic surveillance system.

The Nouna demographic surveillance system database was analysed for the period 1993-98. Basic demographic parameters, age-specific and age-standardized mortality rates were calculated and a seasonal variation in mortality was analysed. Poisson regression was used to model the calculated mortality rates and to investigate the seasonal mortality pattern. Both the population distribution by age and the mortality rates reflect a typical pattern of population structures and total mortality in rural Africa as a whole: high childhood mortality and a young population (about 60% are up to age 25; about 10% above age 64). We identified a significant seasonal pattern with highest mortality rates in February. Demographic surveillance systems in Africa provide a viable method for the collection of reliable data on vital events in rural Africa and should therefore be established and supported.