Sensitivity and Specificity of Nested PCR for Diagnosing Malaria: Cases in Several Areas of Indonesia

Abstract

Indonesia is still included in high endemic area of malaria infection. Early detection as well as appropriate and quick treatment is needed to be able to prevent and treat malaria in Indonesia. Laboratory examination using a microscopic method is still used as the gold standard to diagnose malaria cases. However, the morphology similarity of some Plasmodium species and the number of parasites that can be seen under microscopy causes malaria diagnosis become difficult if only relying on microscopy diagnostic method. The purpose of this study is to analyze the sensitivity and specificity of nested PCR compared to microscopic examination in diagnosing malaria cases. A cross-sectional study has been carried out in some areas of Indonesia and the microscopic analysis as well as nest PCR was done in Laboratory of Parasitology and Laboratory of Central Biomedical Faculty of Medicine, Universitas Brawijaya, Malang East Java Indonesia. A total of 149 blood samples from patients with clinical symptoms of malaria had been obtained from Sumatra, Sulawesi and East Java during December 2011 to December 2013. From 149 sample, 81.9% samples were diagnosed malaria positive by microscopy examination, whereas the PCR results showed that 90.6% of samples were positive. Nested PCR sensitivity is 97.5%, and microscopy 88.2%. Nested PCR specificity is 40.7%, whereas microscopy 78.5%. PPV and NPV for nested PCR are 88,2% and 78.5% respectively, and for microscopy are 97.5% and 40.7% respectively. Nested PCR has a higher sensitivity than microscopy in diagnosing malaria and is able to detect mixed infection better than microscopic examination. However, it is statistically less specific than microscopy examination.

Performance analysis of polymerase chain reaction in relation to rapid diagnostic test (RDT) kit (SD bio line malaria ag p.f (05fk50)) for malaria diagnosis

“…The specificity of PCR (54.41%) reported in this study is by far lower than 99.3% reported by previous research [40] during mass surveys conducted in low and high malaria-endemic areas from two North-Eastern states. The specificity value reported in the present study is contrary to the findings of previous research [41] who reported a specificity value of 97.1% from malaria endemic area in Yemen using PCR diagnostic techniques, but higher than 40.7% [42] from Indonesia. The disparity observed in the specificity value could be attributed to the highest number (66.0%) of samples confirmed to be positive by the RDTs, thus affecting true negative samples.…”

Performance and accuracy of SD Bioline malaria Ag P.f (05fk50) in relation to microscopy as the gold standard technique for malaria diagnosis

“…This disparity in the sensitivity and specificity values recorded in the present study could be ascribed to the false positive and false negative diagnosis which affected the sensitivity and specificity of the RDT. It has reported [38] a high sensitivity value of 97.5% from the PCR diagnostic technique, but with a similar specificity value of 40.7% as recorded in the present study. Differences in sensitivity values of the two techniques might be attributed to the fact that PCR has a very sensitivity as it detects the presence of Plasmodium falciparum below the threshold of other diagnostic techniques like microscopy and RDT, as it can detect as low as 0.01-1parasite/µL of blood [39].…”

The Relationship Between Fetal Weight with Sequestration of Infected Erythrocyte, Monocyte Infiltration, and Malaria Pigment Deposition in Placenta of Mother Giving Birth Suffering from Plasmodium Vivax Infection

“…PCR examination was performed at the Biomedical Central Laboratory, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia, as described previously ( 15 ).…”