Total serum lactate dehydrogenase activity in acute Plasmodium falciparum malaria infection.

INTRODUCTION Lactate dehydrogenase (LDH) activity was assayed in the sera of 76 adult male and 76 adult female patients within the age group of 18-40 years presenting with acute, uncomplicated Plasmodium falciparum malaria infection and a control group of 80 healthy adults within the same age group. METHODS Patient selection and pre-qualification were done by simple random sampling of individuals presenting at the Bauchi Specialist Hospital Outpatient Department with a history of fever and malaise within a period of one to eight days, and who were confirmed to be infected with the P. falciparum malaria parasite by microscopical examination of Giemsa-stained thin blood slides. RESULTS The mean serum LDH activity in male patients was found to be 789.4 +/- 35.0 IU. This activity is significantly higher than the control LDH activity of 247.10 +/- 19.0 IU (p-value is less than 0.05). The mean serum LDH activity among female patients was 634.0 +/- 35.0 IU, which is a relatively higher activity compared to the control LDH activity of 247.10 +/- 19.0 IU (p-value is less than 0.05). CONCLUSION The combination of acute hepatocellular injury and red cell haemolysis induced by the invading merozoites may account for the increase in serum LDH activity during this infection. Therefore serum LDH activity is a potentially valuable enzymatic marker of acute, uncomplicated P. falciparum malaria infection, especially in the absence of other complicating diseases known to be associated with the above normal serum LDH activities.