title: Comparative evaluation of microscopy, OptiMAL(®) and 18S rRNA gene based multiplex PCR for detection of Plasmodium falciparum & Plasmodium vivax from field isolates of Bikaner, India.
abstract: OBJECTIVE
  To evaluate microscopy, OptiMAL(®) and multiplex PCR for the identification of Plasmodium falciparumm (P. falciparum) and Plasmodium vivax (P. vivax) from the field isolates of Bikaner, Rajasthan (Northwest India).
  
  
  METHODS
  In this study, a multiplex PCR (P. falciparum and P. vivax) was further developed with the incorporation of Plasmodium malariae (P. malariae) specific primer and also a positive control. The performance of microscopy, plasmodium lactate dehydrogenase (pLDH) based malaria rapid diagnostic test OptiMAL(®) and 18S rRNA gene based multiplex PCR for the diagnosis of P. falciparum and P. vivax was compared.
  
  
  RESULTS
  The three species multiplex PCR (P. falciparum, P. vivax and P. malariae) with an inbuilt positive control was developed and evaluated. In comparison with multiplex PCR, which showed the sensitivity and specificity of 99.36% (95%CI, 98.11%-100.00%) and 100.00% (95%CI, 100.00%-100.00%), the sensitivity and specificity of microscopy was 90.44% (95%CI, 88.84%-95.04%) and 99.22% (95%CI, 97.71%-100.00%), and OptiMAL(®) was 93.58% (95%CI, 89.75%-97.42%) and 97.69% (95%CI, 95.10%-100.00%). The efficiencies were 99.65%, 95.10% and 95.45% for multiplex PCR, microscopy and OptiMAL(®), respectively.
  
  
  CONCLUSIONS
  Our results raise concerns over the overall sensitivities of microscopy and OptiMAL(®), when compared to the multiplex PCR and thus stress the need for new molecular interventions in the accurate detection of the malarial parasites. This further highlights the fact that further developments are needed to improve the performance of rapid diagnostic tests at field level.
authors.affiliation: Center for Biotechnology, Dept of Biological Sciences, Birla Institute of Technology and Science, Pilani-333031, Rajasthan, India.
authors.forename: Deepak
authors.initials: D
authors.lastname: Pakalapati
authors.forename: Shilpi
authors.initials: S
authors.lastname: Garg
authors.forename: Sheetal
authors.initials: S
authors.lastname: Middha
authors.forename: Abhishek
authors.initials: A
authors.lastname: Kochar
authors.forename: Amit Kumar
authors.initials: AK
authors.lastname: Subudhi
authors.forename: Boopathi Pon
authors.initials: BP
authors.lastname: Arunachalam
authors.forename: Sanjay Kumar
authors.initials: SK
authors.lastname: Kochar
authors.forename: Vishal
authors.initials: V
authors.lastname: Saxena
authors.forename: R P
authors.initials: RP
authors.lastname: Pareek
authors.forename: Jyoti
authors.initials: J
authors.lastname: Acharya
authors.forename: Dhanpat Kumar
authors.initials: DK
authors.lastname: Kochar
authors.forename: Ashis
authors.initials: A
authors.lastname: Das
mesh_terms: D000328:Adult; D002648:Child; D016054:DNA, Protozoan / Q000032:analysis / Q000235:genetics; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D007194:India; D008288:Malaria / Q000175:diagnosis / Q000235:genetics / Q000469:parasitology*; D008853:Microscopy / Q000379:methods; D060885:Multiplex Polymerase Chain Reaction / Q000379:methods*; D010274:Parasitology / Q000379:methods; D010963:Plasmodium falciparum / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification*; D010966:Plasmodium vivax / Q000235:genetics / Q000302:isolation & purification*; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D012680:Sensitivity and Specificity
chemical_list: D016054:DNA, Protozoan; D012337:RNA, Ribosomal, 18S