Evaluation of automated loop-mediated amplification (LAMP) for routine malaria detection in blood samples of German travelers - A cross-sectional study.

Background: We assessed a commercial loop-mediated amplification (LAMP) platform for its reliability as a screening tool for malaria parasite detection.

Methods: A total of 1000 blood samples from patients with suspected or confirmed malaria submitted to the German National Reference Center for Tropical Pathogens were subjected to LAMP using the Meridian illumigene Malaria platform. Results were compared with microscopy from thick and thin blood films in all cases. In case of discordant results between LAMP and microscopy (n = 60), confirmation testing was performed with real-time PCR. Persistence of circulating parasite DNA was analyzed by serial assessments of blood samples following malaria treatment.

Results: Out of 1000 blood samples analyzed, 238 were positive for malaria parasites according to microscopy (n = 181/1000) or PCR (additional n = 57/60). LAMP demonstrated sensitivity of 98.7% (235/238), specificity of 99.6% (759/762), positive predictive value (PPV) of 98.7% (235/238) and negative predictive value (NPV) of 99.6% (759/762), respectively. For first slides of patients with malaria and for follow-up slides, sensitivity values were 99.1% (106/107) and 98.5% (129/131), respectively.

Conclusions: The performance of the Meridian illumigene Malaria platform is suitable for initial screening of patients suspected of clinical malaria.