Background: Many public medical laboratories use automated techniques for analysis of samples due to the few number of laboratory staff required and the speed at which it operates. This study was carried out to compare haematological values obtained from automated techniques and manual techniques.
Method: A total of 86 apparently healthy adult Nigerians, aged 18-50 years comprising 50 males and 36 females who came for medical examination between June, 2004 and May, 2005 at Aminu Kano Teaching Hospital, Kano were used for the study. Standard manual methods and cell-dyn 3700cs system techniques were used to determine haematocrit, total and differential leucocyte counts.
Results: Statistically significant differences were found between automated and manual techniques in males with regard to haematocrit levels, total white cell counts, differential monocyte and basophil counts (0.45 +/- 0.031/1, 5.1 +/- 1.9 x 10(9)/l, 0.54 +/- 0.19 x 10(9)/l and 0.11 +/- 0.08 x 10(9)/l respectively) for automation and 0.42 +/- 0.041/l, 4.4 +/- 1.4 x 10(9)/1, 0.05 +/- 0.06 x 10(9)/l and 0.004 +/- 0.013 x 10(9)/l respectively for manual methods at P < 0.001, P < 0.05, P < 0.001 and P < 0.001 respectively while there were no significant differences in differential neutrophil, lymphocyte and eosinophil counts (2.1 +/- 0.7 x 10(9)/l, 2.2 +/- 0.7 x 10(9)/l and 0.14 +/- 0.16 x 10(9)/l respectively) of the automation when compared to 2.1 +/- 0.5 x 10(9)/l, 2.1 +/- 0.5 x 10(9)/l and 0.09 +/- 0.09 x 10(9)/l respectively using manual methods (P > 0.05). There were no statistically significant differences between automated and manual methods in females with regard to total white cell count, differential neutrophil, lymphocyte and eosinophil counts (5.8 +/- 2.3 x 10(9)/l, 2.6 +/- 0.9 x 10(9)/l, 2.4 +/- 0.8 x 10(9)/l and 0.1 +/- 0.1 x 10(9)/l respectively) of the automation when compared to 4.9 +/- 1.6 x 10(9)/l, 2.5 +/- 0.7 x 10(9)/l, 2.3 +/- 0.6 x 10(9)/l and 0.06 +/- 0.09 x 10(9)/l respectively of manual techniques (P > 0.05) while significant differences were observed in haematocrit, differential monocyte and basophil counts (0.39 +/- 0.03 l/l, 0.55 +/- 0.3 x 10(9)/l and 0.1 +/- 0.09 x 10(9)/l respectively) of automation when compared to 0.37 +/- 0.03 l/l, 0.03 +/- 0.04 x 10(9)/l and 0.002 +/- 0.01 x 10(9)/l respectively of the manual methods at P < 0.01, P < 0.001 and P < 0.001 respectively.
Conclusion: The results have proven that differential monocyte and basophil counts from automation are unreliable and efforts should be made to carry out manual differential counts for confirmation.