Razi Journal of Medical Sciences

Dear Editor: At reviews in my research field, faced to an article published in your journal in Volume 20, Number 106, April 2013 titled "avidity ELISA method in the diagnosis of congenital toxoplasmosis", with interest all looked at it and found we had vague hints as to help promote your Journal referred to them. As you know, the purpose of this study was to determine the prevalence Period of maternal toxoplasmosis of the assessment of IgG Avidity benefited, while we know that with this method, Of course sensitivity is not high eventually with an accuracy of 3-2 months duration can be guessed. Its course, along with the other two sides of the triangle diagnosis of congenital toxoplasmosis or abortion caused by toxoplasmosis, the molecular diagnostics and clinical signs, it’s meaningful (2, 1). Another important point is that in some parts, the Low avidity indicator of infection in the past & High avidity indicate nearly infection (Introduction, paragraph 5) that even with some parts of this paper and other papers apparent contradiction show (3, 4). In methodology part of that paper noted that the ELISA is diagnostic gold standard, in basis of numerous articles, this claim was rejected and molecular methods such as PCR, RealTime-PCR and western blot analysis as an evaluation will be made mandatory. In a paper published Gharavi et al in 2015 have even positive predictive value (PPV) of ELISA Avidity test is about 57% reported that they considered to be very low (1, 4, 5). In materials and methods portion noted that the of phosphate and urea treatment should be used only in quantitative ELISA Avidity is need but not in semi-quantitative, While the basis of numerous articles in both cases, to odd and even plates Respectively urea & phosphate buffers added to antibody-antigen adept of tight junctions (the avidity) measured (6, 4). Of course on research methodology can be noted that another important point to lack of statistical analysis results, so that none of the variables using statistical tests have not been studied. Compare the results of a liquid kit and Amniotic fluid in maternal serum using paired t-test, or check the number of abortions significantly associated with the results of kit mothers using independent t-test, including those to be ignored (7).

Finally, in discussion mentioned out by IgM ELISA test can definitively diagnose the presence of parasites in the patient presented, and to differentiate the case of pre- and post-pregnancy Infection, Dye Test methods will be used. It is noteworthy that IgM ELISA does not have a very high sensitivity and comprising false & negative positive which it is not confirmed by Dye Test (Sabin Feldman also called). Nowadays the risk of operating, cost and high failure chance of that methods cause molecular methods such as nested PCR and RealTime PCR and Western blot was replaced (8,9). Various studies have also shown that various immunological methods such as Immunofluorescent can be trusted more than the ELISA (10).

At the end, we thanking the authors of the article and respect their efforts we have been told that because of improve the view of readers noticed you merely. We hope that by presenting better and more perfect articles help our country to scientific evolvement.