Comparative Study of Peripheral Blood Smear, Rapid Antigen Detection, ELISA and PCR Methods for Diagnosis of Malaria in a Tertiary Care Centre DC08-DC11
Dr. Vasanthi Rompicherla,
Flat No. 1A, Ram Beuan Havens Apartments, Natham Link Road, Egattur, Chennai-603103, Tamil Nadu, India.
Introduction: Diagnosis of malaria is largely influenced by the quality and design of the method used and antigenic variation exhibited by the parasite. Appropriate selection of these tests is necessary for routine case investigation, screening and for monitoring the response to various antimalarial agents.
Aim: To evaluate the blood samples collected from suspected patients of malaria by various diagnostic methods.
Materials and Methods: A total of 100 blood samples were collected from suspected cases of malaria from January 2015 to January 2016. The blood samples were screened by microscopy, rapid malaria antigen detection method (Histidine Rich Protein-2 and Lactate dehydrogenase), solid phase ELISA (Lactate dehydrogenase) and conventional PCR for 18s rRNA.
Results: PCR was found to be the most sensitive method from this study. The specificity and positive predictive values were 100% for microscopy, rapid antigen detection method and ELISA. The negative predictive values were 94.4% for microscopy and rapid tests, followed by 93.5% for ELISA. The sensitivity was 75% for microscopy and rapid tests and 70% for ELISA.
Conclusion: In this study PCR was found to be the most sensitive method which gave more positive results, followed by microscopy and rapid antigen detection methods, whereas ELISA was the least.