Testing the sensitivity and specificity of the fluorescence microscope (Cyscope(®)) for malaria diagnosis

BACKGROUND: Early diagnosis and treatment of malaria are necessary components in the control of malaria. The gold standard light microscopy technique has high sensitivity, but is a relatively time-consuming procedure especially during epidemics and in areas of high endemicity. This study attempted to test the sensitivity and specificity of a new diagnostic tool - the Cyscope(® )fluorescence microscope, which is based on the use of Plasmodium nucleic acid-specific fluorescent dyes to facilitate detection of the parasites even in low parasitaemia conditions due to the contrast with the background. METHODS: In this study, 293 febrile patients above the age of 18 years attending the malaria treatment centre in Sinnar State (Sudan) were interviewed using a structured questionnaire. Finger-prick blood samples were also collected from the participants to be tested for malaria using the hospital's microscope, the reference laboratory microscope, as well as the Cyscope(® )microscope. The results of the investigations were then used to calculate the sensitivity, specificity, and positive and negative predictive values of the Cyscope(® )microscope in reference to gold standard light microscopy. RESULTS: The sensitivity was found to be 98.2% (95% CI: 90.6%-100%); specificity = 98.3% (95% CI: 95.7% - 99.5%); positive predictive value = 93.3% (95% CI: 83.8% - 98.2%); and negative predictive value = 99.6% (95% CI: 97.6% - 100%). CONCLUSIONS: In conclusion, the Cyscope(® )microscope was found to be sensitive, specific and provide rapid, reliable results in a matter of less than 10 minutes. The Cyscope(® )microscope should be considered as a viable, cheaper and time-saving option for malaria diagnosis, especially in areas where Plasmodium falciparum is the predominant parasite.