Mitochondrial PCR-based malaria detection in saliva and urine of symptomatic patients.
BACKGROUND
Malaria can be diagnosed in saliva and urine using mitochondrial PCR detection of Plasmodium DNA.


METHODS
Blood, saliva and urine were collected from 99 febrile patients referred to health centers in Sistan and Baluchestan Province, southeastern Iran, from May to November 2011. The mitochondrial cytochrome b gene of Plasmodium falciparum and Plasmodium vivax was targeted in saliva, urine and blood samples using nested PCR.


RESULTS
Nested PCR proved to be more sensitive than microscopy for the diagnosis of sub-microscopic and mixed-species infections. The results of nested PCR amplifications of saliva and urine samples showed the same specificity of 97% and sensitivity of 91% and 70%, respectively. Nested PCR amplifications of saliva samples and microscopy showed the greatest area under the receiver operating characteristic (ROC) curve and were more accurate than nested PCR amplifications of urine samples.


CONCLUSIONS
Nested PCR amplification of saliva samples showed good levels of detection of mitochondrial Plasmodium DNA as compared to nested PCR of blood (к=0.84; AUC=0.94), which was used as a reference standard. Based on the results of nested PCR as well as the advantages of saliva sampling, we suggest that saliva could be an alternative to blood, in malaria diagnosis, in cases where repeat sampling is required. Further studies are needed to validate these findings.
Department of Parasitology and Mycology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
Zahra
Z
Ghayour Najafabadi
Department of Parasitology and Mycology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
Hormozd
H
Oormazdi
Department of Parasitology and Mycology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
Lame
L
Akhlaghi
Department of Parasitology and Mycology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
Ahmad Reza
AR
Meamar
Department of Medical Entomology and Vector Control, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
Ahmad
A
Raeisi
Department of Community Medicine, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
Zahra
Z
Rampisheh
Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
Mehdi
M
Nateghpour
Department of Parasitology and Mycology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran razmjou.e@iums.ac.ir.
Elham
E
Razmjou
D004272:DNA, Mitochondrial / Q000032:analysis*; D016054:DNA, Protozoan / Q000032:analysis*; D006801:Humans; D007492:Iran / Q000453:epidemiology; D016778:Malaria, Falciparum / Q000175:diagnosis* / Q000378:metabolism / Q000469:parasitology; D016780:Malaria, Vivax / Q000175:diagnosis* / Q000378:metabolism / Q000469:parasitology; D010963:Plasmodium falciparum / Q000302:isolation & purification*; D010966:Plasmodium vivax / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction / Q000379:methods / Q000592:standards*; D012372:ROC Curve; D012463:Saliva / Q000737:chemistry / Q000469:parasitology; D012680:Sensitivity and Specificity; D014556:Urine / Q000737:chemistry / Q000469:parasitology
D004272:DNA, Mitochondrial; D016054:DNA, Protozoan
Malaria diagnosis; Mitochondrial nested PCR; Plasmodium falciparum; Plasmodium vivax; Saliva; Urine