title: Challenges in diagnosis of Plasmodium knowlesi infections.
abstract: Plasmodium knowlesi is the fifth species of Plasmodium recently identified to cause human malaria. Infections with P. knowlesi are currently being reported from South-East Asian countries and the incidence is on the rise with a possibility of spread to the geographically contiguous countries. P. knowlesi infections can result in a high degree of parasitemia causing severe malaria in a larger proportion of infected individuals. If detected early and treated with appropriate antimicrobials, these infections show a significant clinical improvement. The widely used microscopic methods usually misidentify P. knowlesi as the less pathogenic Plasmodium malariae leading to inadequate therapy and adverse clinical outcomes. The currently popular rapid immuno-chromatographic card tests have a very low sensitivity in diagnosing knowlesi malaria and can erroneously report P. knowlesi as other Plasmodia and vice-versa. At present molecular methods are the most efficacious in diagnosing P. knowlesi infections, but these tests can produce a false positive report in Plasmodium vivax infections and require expensive equipment and trained personnel. An ideal diagnostic test for P. knowlesi infections, which is potent, cost-effective and practically feasible in the resource limited setting is yet to be developed.
authors.affiliation: Department of Microbiology, Velammal Medical College Hospital and Research Institute, Madurai, Tamil Nadu, India.
authors.forename: Ss
authors.initials: S
authors.lastname: Jeremiah
authors.affiliation: Department of Microbiology, Velammal Medical College Hospital and Research Institute, Madurai, Tamil Nadu, India.
authors.forename: Anand B
authors.initials: AB
authors.lastname: Janagond
authors.affiliation: Department of Microbiology, JIPMER, Puducherry, India.
authors.forename: Subhash Chandra
authors.initials: SC
authors.lastname: Parija
keywords: Microscopy; Plasmodium knowlesi; rapid diagnostic test; real time polymerase chain reaction; severe malaria
references.citation: Clin Infect Dis. 2012 Jun;54(11):1637-41
references.pmid: 22550113
references.citation: Clin Infect Dis. 2011 Jun;52(11):1356-62
references.pmid: 21596677
references.citation: Malar J. 2012 Aug 20;11:284
references.pmid: 22905799
references.citation: Malar J. 2012 May 08;11:159
references.pmid: 22569198
references.citation: Parasit Vectors. 2008 Aug 19;1(1):26
references.pmid: 18710577
references.citation: Clin Infect Dis. 2009 Sep 15;49(6):852-60
references.pmid: 19635025
references.citation: J Clin Microbiol. 2009 Dec;47(12):4173-5
references.pmid: 19812279
references.citation: Clin Infect Dis. 2008 Jan 15;46(2):165-71
references.pmid: 18171245
references.citation: Malar J. 2009 Apr 21;8:73
references.pmid: 19383118
references.citation: Protein Expr Purif. 2012 Aug;84(2):195-203
references.pmid: 22683723
references.citation: Southeast Asian J Trop Med Public Health. 2010 Jan;41(1):19-21
references.pmid: 20578477
references.citation: Clin Microbiol Rev. 2007 Jan;20(1):188-204
references.pmid: 17223628
references.citation: Nucleic Acids Res. 2000 Jun 15;28(12):E63
references.pmid: 10871386
references.citation: Malar J. 2013 Sep 22;12:336
references.pmid: 24053759
references.citation: Malar J. 2013 Dec 19;12:454
references.pmid: 24354660
references.citation: PLoS One. 2012;7(2):e31848
references.pmid: 22363751
references.citation: Trop Med Health. 2013 Jun;41(2):55-9
references.pmid: 23874139
references.citation: Lancet. 2004 Mar 27;363(9414):1017-24
references.pmid: 15051281
references.citation: Am J Trop Med Hyg. 2013 Oct;89(4):721-723
references.pmid: 23980132
references.citation: Malar J. 2011 Jul 20;10:197
references.pmid: 21774805
references.citation: Clin Microbiol Rev. 2013 Apr;26(2):165-84
references.pmid: 23554413
references.citation: Emerg Infect Dis. 2008 Nov;14(11):1750-2
references.pmid: 18976561
references.citation: J Clin Microbiol. 2013 Apr;51(4):1118-23
references.pmid: 23345297
references.citation: Malar J. 2013 Sep 13;12:321
references.pmid: 24034175
references.citation: Clin Infect Dis. 2013 Feb;56(3):383-97
references.pmid: 23087389
references.citation: Public Health Genomics. 2013;16(1-2):37-43
references.pmid: 23548716
references.citation: Malar J. 2012 Oct 30;11:363
references.pmid: 23110615
references.citation: Malar J. 2013 Jan 08;12:8
references.pmid: 23294844
references.citation: Am J Trop Med Hyg. 2009 Sep;81(3):516-8
references.pmid: 19706924
references.citation: Malar J. 2013 Jun 04;12:182
references.pmid: 23734702
references.citation: J Clin Microbiol. 2010 Jul;48(7):2509-14
references.pmid: 20444968
references.citation: Mem Inst Oswaldo Cruz. 2011 Aug;106 Suppl 1:52-63
references.pmid: 21881757
references.citation: Parasitol Int. 2009 Sep;58(3):300-2
references.pmid: 19527797
references.citation: Malar J. 2013 Jul 31;12:264
references.pmid: 23902626
references.citation: J Clin Microbiol. 2012 Dec;50(12):4012-9
references.pmid: 23035191
references.citation: Am J Trop Med Hyg. 2013 May;88(5):835-40
references.pmid: 23509118
references.citation: Malar J. 2010 Nov 30;9:344
references.pmid: 21114872
references.citation: Clin Microbiol Rev. 2002 Jan;15(1):66-78
references.pmid: 11781267
references.citation: J Clin Microbiol. 2009 Apr;47(4):975-80
references.pmid: 19244467