الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Toxoplasmosis is a disease caused by a protozoan parasite, Toxoplasma gondii. Acute infection or reactivation of latent infection in a pregnant woman can be transmitted to the fetus and may cause mental retardation, blindness, encephalitis, epilepsy and/or death. The condition becomes severe among immune-compromised individuals as AIDS, transplant recipients and cancer patients treated with immunosuppressive drugs. However, adults with normal immune function are usually asymptomatic or have mild symptoms such as fever, malaise, lymphadenopathy that resolve spontaneously.
Most T.gondii infections occur by eating raw or undercooked meat containing T.gondii tissue cysts or by ingesting oocysts from soil as through gardening, eating unwashed vegetables, changing a cat litter box or by acquiring congenital infection.
The present study comprised the following specific objectives:
1- To detect the sero-positive pregnant women for T.gondii specific antibodies IgM and IgG using both Enzyme-Linked Immunosorbent Assay (ELISA) and Immunochromatographic assay (ICA) as a rapid diagnostic test (RDT).
2- To determine factors associated with T.gondii infection.
3- To evaluate the validity of RDT in diagnosing T.gondii infection among pregnant women compared to ELISA technique as a diagnostic gold standard.
The study protocol was reviewed and approved by the Ethical Review Committee of the HIPH, Alexandria University.
Informed consent was taken from all participants who agreed to participate in the study after explaining the purpose and the objectives of the work.
The operational phase extended from the beginning of May 2014 till mid of June
2015.
The study was done in five randomly selected antenatal care centers in Alexandria
representing various sectors providing antenatal care services for pregnant women; two representing Non-Governmental Organizations (NGOs) (El-Ibrahimia and Moharem-Bey). They are belonging to Alexandria Family Planning Association (AFPA), and one representing Ministry of Health and Population (MOHP) (health unit of Ezbet Danna). Private sector was also included (one private gynecology and obstetric clinic in Ezbet Skina and one private hospital (El-Riada private hospital in El-Asafra).
The target population was composed of all pregnant women who attended the randomly selected antenatal care centres for examination and follow up. Each centre was visited twice a week. All pregnant women were enrolled in the study as long as they fulfilled the inclusion criteria till the computed required sample size was reached-382 pregnant women. The inclusion criteria were current pregnancy, response to all questionnaire items and Toxoplasma serology.
The enrolled participants were classified according to their residential area by district into: fifty eight cases from El-Montaza district (El-Asafra 25 cases, Sidi-Beshr 21 cases, El-Awayed 11 cases, and El-Maemora 1case). Eighty cases from Sharque district (Ezbet
Sikina 47 cases, and Ezbet Danna 33 cases). Two hundred and forty three cases from Wasat district (El-Hadra 207 cases, Moharem-Bey 29 cases and El-Shatby 7 cases), and one case from El-Agmy district.
Data collection methods:
1- Questionnaire:
All participants were interviewed at the first medical consultation using the pretested questionnaire to assess the sociodemographic data, history of pathological pregnancy, medical history and lifestyle-related risk factors. The questionnaires were applied at face- to-face interviews. The questions were answered orally by the interviewers and recorded by the researcher, so that the participant would find it easier to understand the subject matter.
2- Laboratory studies:
About 4ml of venous blood were drawn in pre-labeled test tube. All samples were left to coagulate then centrifuged to obtain clear-non haemolyzed sera. The sera were divided into two parts: The first part was examined by RDT. The other part was stored at
-20°C till to be examined by ELISA assay. Both techniques were performed for determining specific anti-T.gondii IgG and IgM antibodies. The procedures of the techniques were followed up according to manufacturer’s instructions.
The recorded data were entered into the computer and analyzed using a statistical package SPSS (version 21). The association between toxoplasmosis and possible risk factors were tested by appropriate statistical procedures.
The main findings of the present study were summarized as follows:
1- Out of 382 examined pregnant women, RDT detected 11.3% infected cases, significantly increased to 57.9% cases by ELISA technique.
2- The distribution of anti-Toxoplasma specific antibodies was: IgG (+ve) and IgM (-ve) which indicated a previous exposure or chronic infection were 57.33% and 11.3% among pregnant women as detected by ELISA and RDT respectively. The positive result of both IgG and IgM (IgG/IgM +ve) indicating probable primary infection or reactivation of chronic infection was 0.52% had diagnosed by ELISA only. The negative results for both IgG and IgM indicating susceptible cases were 42.2% and 88.7% as diagnosed by ELISA and RDT respectively.
3- ELISA technique detected more positive cases than RDT. The obtained results showed that 186 cases reported positive by ELISA assay that were negative by RDT. Only 8 cases were positive by RDT that were negative by ELISA test. Cohen’s Kappa coefficient (k) was 0.094 indicating a slight agreement between RDT and ELISA assay as diagnostic gold standard technique.
4- The diagnostic parameters of RDT versus ELISA assay as diagnostic gold standard showed that RDT had the sensitivity of 15.8%, the specificity of 95%, PPV of 81.4%, NPV of 45.1%, with overall diagnostic efficiency of 49.2%. The DA was 26.5% and AUC was 0.554.
5- The seroprevalence of T.gondii infection in relation to the history of exposure to different risk factors of T.gondii infection was as follows:
a- Sociodemographic characteristics: The age of the participants ranged between 17-44 years with overall mean of 26.71±5.27years. The majority of infected women were of age category 25 – 34 years (53.4%), while the least prevalence was among those aged between 35 - 44 years (12.2%). The association between T.gondii infection and the age of the pregnant women was found to be statistically significant. Most of infected pregnant women were house wives (91%), secondary educated (44.3%), and those residing El-Hadra area was the most prevalent group (54.8%). The association between the seropositivity and these factors was not statistically significant.
b- Animal rearing risk factors: Only 5.0% of the infected pregnant women had cats in their households. The majority of infected cases (90.9%) were feeding their cats with table food, 54.5% of them were removing the cat’s feces without using gloves and 12.5% of them didn’t wash their hands after removing the cat’s feces. Twenty six cases (11.8%) of seropositive pregnant women were rearing other animals as chickens or ducks in their households. There was no statistically significant relationship between the seropropositive pregnant women and animal rearing risk factors.
c- Ways of cooking and kitchen hygiene: The majority of the seropositive pregnant women (96.4 %) were eating well done meat. Only 34.8% were eating raw vegetables and fruits outdoors. About 99% of them were washing their vegetables before eating, 37.6% of them were using running tap water, 42.2% rinse in the collected water and 20.2% rinsing in water with vinegar. Most of the infected pregnant women were washing their hands and utensils before cooking (73.8% and 67.9% respectively). About 67% of the seropositive pregnant women were washing their knives before cooking and about 85% of them using the same knife for cutting vegetables and meat. About 47% of the seropositive pregnant women were using a cutting board. Only 13.5% of them were using separate cutting board for vegetables and meat. The majority of infected participants (98.9%) were washing the cutting board before use. About 67% of the infected participants were consuming ready-to-eat processed meat as Lancheon and Basterma and about 69% were consuming fresh milk/milk products. There was no statistically significant relationship between T.gondii infection and any of these risk variables.
d- Obstetric variables: The majority of the seropositive pregnant women (44.3%) were found to be in the second trimester, and about 45% of them were belonging to multigravidae category. About 31% had delivered once and 23% of them gave a history of abortion. About half of the seropositive pregnant women (45%) gave a history of normal delivery and 31% had a history of caesarean sections. About 69% of them gave a history of delivery of normal babies and 4.5% had delivered abnormal babies. Abnormal babies mean that babies delivered with structural anomalies causing congenital birth defects as heart and kidney defects. Only 7.2% of them had a history of delivered underweight babies (≤ 2499 g). There was no statistically significant relationship between seropositive pregnant women and the previously mentioned obstetric variables except for that concerned with delivery of abnormal babies.
e- Clinical and laboratory findings: Out of total seropositive pregnant women; 3.6% had history of chronic diseases as diabetes mellitus, renal diseases, cardiac diseases or bronchial asthma. About 3% of them had a history of blood
transfusion, 78% had normal blood pressure, 10% suffered from foot edema, 1.8% glucosurea and 5.0% albuminurea. There was no statistical significant relationship between seropositive pregnant women and these variables.
f- Knowledge about toxoplasmosis as a disease: The majority of the seropositive participants (94.6%) had no knowledge about toxoplasmosis as a disease. from those who had some knowledge, 25% and 33.3% had no knowledge about the routes of transmission or the different methods used for the prevention of that disease respectively. There was no statistically significant association between T.gondii infection and any of these possible risk variables.
6- Multivariate logistic regression analysis of risk factors for T.gondii infection among the studied sample revealed that only age factor remained significant. But history of abnormal babies that was significantly associated with the seropositivity of T.gondii infection turned to insignificant after it was adjusted for some of the significant explanatory variables. The classification accuracy of the model was 61% of cases.
In conclusion, Egypt is not taking a basic step to prevent toxoplasmosis in pregnant women. There is no definite and precise figure for the rate of primary infection and congenital toxoplasmosis during pregnancy in Egypt. The serological screening for toxoplasmosis is not a routine checkup for any pregnant women attending antenatal care clinics. Pregnant women should be screened at the first prenatal visit and seronegative pregnant women are retested monthly until delivery. If seroconversion occurs during pregnancy, women are promptly treated with antiparasitic medications. Screening is urgently needed because toxoplasmosis can occur even in pregnant women who carefully avoid known transmission methods as infection can occur without any symptoms in most of the pregnant mothers. Pregnant woman has the right to know whether her baby is at risk, or has been infected. The screening of T.gondii infection and implementation of health education program for all pregnant women during antenatal care should be considered in Egypt as the main strategy to minimize congenital toxoplasmosis.