|Year : 2012 | Volume
| Issue : 2 | Page : 251
Diagnosis of congenital toxoplasmosis by polymerase chain reaction
S Rasti1, M Behrashi2, B Kazemi3, A Fatahian2, G Mousavi4, M Namakchian3
1 Department of Laboratory Medicine and Parasitology, Paramedicine Faculty, Kashan University of Medical Sciences, Kashan, Iran
2 Department of Obstetrics and Gynecology, Kashan University of Medical Sciences, Kashan, Iran
3 Department of Parasitology, Cellular and Molecular Biology Research Center, Shahid Beheshti University, Tehran, Iran
4 Department of Statistics, Kashan University of Medical Sciences, Kashan, Iran
|Date of Submission||21-Dec-2010|
|Date of Acceptance||02-Apr-2011|
|Date of Web Publication||28-May-2012|
Department of Obstetrics and Gynecology, Kashan University of Medical Sciences, Kashan
|How to cite this article:|
Rasti S, Behrashi M, Kazemi B, Fatahian A, Mousavi G, Namakchian M. Diagnosis of congenital toxoplasmosis by polymerase chain reaction. Indian J Med Microbiol 2012;30:251
|How to cite this URL:|
Rasti S, Behrashi M, Kazemi B, Fatahian A, Mousavi G, Namakchian M. Diagnosis of congenital toxoplasmosis by polymerase chain reaction. Indian J Med Microbiol [serial online] 2012 [cited 2013 May 24];30:251. Available from: http://www.ijmm.org/text.asp?2012/30/2/251/96725
Congenital Toxoplasmosis may occur after primary infection during pregnancy, which can cause severe complications and rapid diagnosis is required to start efficient treatment. , Detection of parasite DNA by polymerase chain reaction (PCR) represents an alternative choice to serological test.  This study was conducted to diagnose congenital toxoplasmosis by PCR in Kashan, Iran.
In this prospective cohort study, blood samples of 798 pregnant women with gestational age more than 27 weeks during 2007-2009 were examined by ELISA/IgG and IgM (ADALITIS kit, Italy) and ultrasonography. Acute maternal T. gondii infections as well as those with chronic infection were served as case and control groups, respectively. Nested PCR by G529 primers  and ELISA/IgM were performed on four neonates of case group and five samples of control group. Data were analysed by SPSS using Fisher Exact and Chi-Square tests.
Out of the 798 pregnant women, four were positive for IgM 1/100 and ELISA/IgG more than 1/400 represents acute toxoplasmosis (Case group). Nested PCR showed a 400 bp in three newborns of case group considered as parasitemia; positive, but was negative in control group [Figure 1] (P=0.048). About 75% of newborns of case group were positive. Incident rate of congenital toxoplasmosis was 3.7 per 1000 live births that was higher than 3.3 per 10000 in France.  None of the newborns of case and control were positive by ELISA/IgM. Negative serologic test does not reject the possibility of congenital infection.  Congenital toxoplasmosis has been successfully diagnosed by PCR in blood.  Sensitivity of PCR increases with the gestational age at maternal seroconversion; increased to 76% in the third trimester,  and our research findings were according to previous study.  PCR is a reliable, quick, accurate and specific method for diagnosis of infection in foetus.  In general, the results of ultrasonography in all pregnant women were normal.
|Figure 1: Electrophoresis of nested PCR product of infected newborns with Toxoplasmosis. Lanes 1, 5, 6: Nested PCR product of infected infants with 400 bp band. Lane 4: Ladder 50 bp with band 250 bp and 500 bp. Lanes 2, 3 Negative and positive controls|
Click here to view
| ~ Acknowledgments|| |
The study was funded by Vice Chancellor for Research of Kashan University of Medical Sciences with grant Number 8607 and brought out as a part of residency's thesis. The authors are thankful to Professor Rezvan Moniri and Jafar Asgari Arani for revising the article and Mojgan Bandehpour at the Cellular and Molecular centre Research of Shahid Beheshti University of Medical Sciences, Tehran.
| ~ References|| |
|1.||Montoya JG, Kovacs JA, Remington JS. Toxoplasma gondii. In: Mandell GL, Bennet JE, Dolin R, editors. Mandell, Douglas and Bonnet's Principle and Practice of Infectious Disease. 6 th ed. Philadelphia: Elsevier Churchill Livingstone; 2005. p. 3170-90. |
|2.||Gilbert R, Williams K, Lockwood Ch J, Waller PF, Barss VA. Toxoplasmosis and pregnancy.version 18.2: May 2010. Available from: http://www.uptodate.com online. |
|3.||Homan WL, Vercammen M, De Braekeleer J, Verschueren H. Identification of a 200-to 300- fold repetitive 529 bp DNA fragment in Toxoplasma gondii , and its use for diagnostic and quantitative PCR. Int J Parasitol 2000; 30: 69-75. |
|4.||Villena I, Ancelle T, Delmas C, Garcia P, Brezin AP, Thulliez P, et al. Congenital toxoplasmosis in France in 2007: First results from a national surveillance system. Euro Surveill 2010;15:19600. |
|5.||Slawska H, Pendzich J, Czuba B, Mazurek U, Gola J, Wilczok T, et al. Detection of Toxoplasma gondii DNA by PCR in mother's blood, amniotic fluid and child's blood in selected cases of pathological pregnancy. Wiad Parazytol 2001;47:99-105. |