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This study investigated loop-mediated isothermal amplification (LAMP) detection of Plasmodium falciparum and Plasmodium vivax in urine and saliva of malaria patients. From May to November 2011, 108 febrile patients referred to health centers in Sistan and Baluchestan Province of south-eastern Iran participated in the study. Saliva, urine, and blood samples were analyzed with nested PCR and LAMP targeting the species-specific nucleotide sequence of small subunit ribosomal RNA gene (18S rRNA) of P. falciparum and P. vivax and evaluated for diagnostic accuracy by comparison to blood nested PCR assay. When nested PCR of blood is used as standard, microscopy and nested PCR of saliva and urine samples showed sensitivity of 97.2%, 89.4% and 71% and specificity of 100%, 97.3% and 100%, respectively. LAMP sensitivity of blood, saliva, and urine was 95.8%, 47% and 29%, respectively, whereas LAMP specificity of these samples was 100%. Microscopy and nested PCR of saliva and LAMP of blood were comparable to nested PCR of blood (к=0.95, 0.83, and 0.94, respectively), but agreement for nested PCR of urine was moderate (к=0.64) and poor to fair for saliva LAMP and urine LAMP (к=0.38 and 0.23, respectively). LAMP assay showed low sensitivity for detection of Plasmodium DNA in human saliva and urine compared to results with blood and to nested PCR of blood, saliva, and urine. However, considering the advantages of LAMP technology and of saliva and urine sampling, further research into the method is worthwhile. LAMP protocol and precise preparation protocols need to be defined and optimized for template DNA of saliva and urine., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Introduction: Fosmidomycin is a phosphonic acid derivative originally isolated as a natural antibiotic from Streptomyces lavendulae. It was originally used as an antibiotic, and later on as an antimalarial drug. A simple, sensitive, selective and reproducible bioassay based on colorimetric method was developed for the determination of fosmidomycin in human plasma and urine., Methods and Results: Enterobacter cloacae ATCC 23355 strain was used as a test organism. Inhibition of bacterial growth was assessed using MTT assay. Calibration curves were prepared from concentration response curves in plasma (0, 0.5, 1, 2.5, 5, 12.5, 25, 50 ng/microl) and urine (0, 0.5, 1, 2.5, 5, 12.5, 25, 50 and 100 ng/microl) and were all linear with correlation coefficients better than 0.990. The precision of the method based on within-day repeatability and reproducibility (day-to-day variation) was below 10% (% coefficient of variations: % C.V.) Good accuracy was observed for both the intra-day and inter-day assays, as indicated by the minimal deviation of mean values found between the measured samples and the theoretical values (below +/-10%). Limit of quantification (L.O.Q.) was accepted as 0.5 ng using 20 microl plasma or 10 microl urine sample. The mean recovery for fosmidomycin was greater than 99%. The method was free from interference from other commonly used antibiotics., Discussion: The analytical method established in this study meets the criteria of high sensitivity, accuracy and reproducibility for routine use in pharmacokinetic studies. The method has advantages over the recently developed bioassay in its simplicity, accuracy, short analysis time, good sensitivity, and the requirement for smaller volumes of samples. The method appears to be robust and has been applied to a pharmacokinetic study to determine the plasma and urinary excretion of fosmidomycin in a total of 24 Thai patients with acute uncomplicated falciparum malaria following oral doses of 1800 fosmidomycin given every 10 h for 3 days., (2010 Elsevier Inc. All rights reserved.)