The effect of <i>Plasmodium falciparum</i> malaria on platelet counts in patients attending the University of Calabar Teaching Hospital, Nigeria

Abstract

This prospective cross-sectional study was aimed at assessing the effect of Plasmodium falciparum malaria on platelet count among various categories of hospital patients in the University of Calabar Teaching Hospital, Calabar, Nigeria. A total of six hundred and ten (610) patients participated in the study and three hundred and sixty (360) non-malaria infected patients were used as controls. The prevalence rate of Plasmodium falciparum malaria in this study was 40.98%. The mean platelet count of 113 ± 57 x 10⁹/L observed in the malaria infected patients was found to be significantly lower than the mean count of 168 ± 48 x 10⁹/L in the non-infected subjects (controls) (t = 4.867, P<0.001). The highest prevalence rate of 68.10% occurred in children aged 1-12 years and their platelet counts of 110 ± 41 x 10⁹/L was significantly lower than the control value of 166 ± 85 x 10⁹/L (t = 4.696, P<0.001). The platelet count of 103 ± 41 x 10/L observed in pregnant women was also statistically significant when compared with 168 ± 76 x 10⁹/L in the non infected pregnant women. (t = 3.051, P<0.01). Mild significant depression also occurred in adults aged 18 years and above (t = 2.575, P<0.05). The effect of Plasmodium falciparum malaria on platelet count was not significant in adolescents aged 13 17 years. (t = 0.047, P>0.05). The mean haematocrit value obtained in this study was 0.35l/l. The mean haematocrit values of 0.33 ± 0.07l/l in a Pf 2+ infection and 0.35 ± 0.06l/l in a Pf 1+ infection was not found to be statistically different (t = 0.33, P>0.05). The reduction in platelet count and haematocrit values was found to be independent of the degree of parasitaemia. Thrombocytopenia might therefore be one of the useful indicators of 166 ± 85 x 10⁹/L (t = 4.696, P<0.001). The platelet count of 103 ± 41 x 10/L observed in pregnant women was also statistically significant when compared with 168 ± 76 x 10⁹/L in the non infected pregnant women. (t = 3.051, P < 0.01). Mild significant depression also occurred in adults aged 18 years and above (t = 2.575, P<0.05). The effect of Plasmodium falciparum malaria on platelet count was not significant in adolescents aged 13 17 years. (t = 0.047, P>0.05). The mean haematocrit value obtained in this study was 0.35l/l. The mean haematocrit values of 0.33 ± 0.07l/l in a Pf 2+ infection and 0.35 ± 0.06l/l in a Pf 1+ infection was not found to be statistically different (t = 0.33, P>0.05). The reduction in platelet count and haematocrit values was found to be independent of the degree of parasitaemia. Thrombocytopenia might therefore be one of the useful indicators of Plasmodium falciparum malaria in children and pregnant women.

Keywords: Plasmodium falciparum, malaria, platelet count, thrombocytopenia, Calabar, Nigeria

Highland Medical Research Journal Vol. 3(2) 2005: 15-23