Factors Associated with Toxoplasma gondii Seroprevalence in Pregnant Women: A Cross-Sectional Study in Belgrade, Serbia.

Toxoplasmosis, caused by the cosmopolitan protozoan Toxoplasma gondii, has particular implications during pregnancy due to the possible transmission of infection to the fetus. Very few studies have assessed seroprevalence and the risk factors for toxoplasmosis in healthy pregnant women. The aim of this study was to examine the seroprevalence of T. gondii infection in healthy pregnant women and to identify the associated risk factors for toxoplasmosis. The cross-sectional study involved 300 healthy pregnant women who came to the Institute for Blood Transfusion in Belgrade between November 2018 and February 2019 for routine blood group and Rh factor testing before delivery, who were also tested using serological screening for the presence of specific antibodies. Positives were further examined using enzyme immunoassay. Of the total sera of participants analyzed, 38 were positive for specific IgG, resulting in a seroprevalence rate of 12.7% (95% Confidence Interval (CI) 9.1-17.0%). All pregnant women presented negative anti-T. gondii IgM antibodies. The multivariate logistic regression analysis revealed that living in a house with a garden was independently associated with the risk of T. gondii infections, while eating chicken meat was connected with a lower risk compared to eating other types of meat with an odds ratio (OR) of 2.5 (95% CI 1.21-5.02) and an OR of 0.3 (95% CI 0.09-0.83), respectively. Although the prevalence of anti-T. gondii IgG antibodies is relatively low, it is essential to maintain and adapt evidence-based preventive measures for toxoplasmosis continually.

Epidemiology of Toxoplasmosis in SERBIA: A Cross-Sectional Study on Blood Donors.

Toxoplasmosis is a globally distributed parasitic zoonosis, affecting approximately one third of the human population. Epidemiological studies on toxoplasmosis conducted in Serbia so far have been focused on women of childbearing age, without a clear insight into the prevalence in the general population. We conducted a cross-sectional study in a representative sample of the healthy adult population consisting of 1095 blood donors of both genders to establish the prevalence and risk factors for Toxoplasma gondii infection. Data on the demographic and clinical characteristics of all study participants, as well as on their lifestyle habits, were collected by means of a questionnaire. The overall prevalence of infection was 20.5% (224/1095) and the avidity of the specific IgG antibodies detected was high in a vast majority of the seropositive donors (98.2%). Interestingly, the remaining 1.8% of the specific IgG positive samples were of borderline avidity (4/224), in complete absence of specific IgM. The multivariate logistic regression analysis showed that independent risk factors included age (from OR (95% CI) 1.9 (1.13−3.28) in the 30−39 age group, to 6.8 (3.27−14.24) in the age group of >60 years), suburban living (OR (95% CI) 2.2 (1.43−3.34)) and contact with soil (OR (95% CI) 1.4 (1.01−1.94)). This first large-scale study on toxoplasmosis in the general population in Serbia shows the lowest prevalence ever reported in this country. Moreover, the novel perspective on risk factors provides an updated basis for future prevention programs.

Genotyping of Eight Human Platelet Antigen Systems in Serbian Blood Donors: Foundation for Platelet Apheresis Registry.

INTRODUCTION: The aim of this study was to investigate the allele and genotype frequencies of 8 human platelet antigen (HPA) systems among blood donors from the Blood Transfusion Institute of Serbia and to compare them with published studies. These data would be useful to establish the basis for a platelet apheresis donor registry. MATERIAL AND METHODS: Seventy-two unrelated male platelet apheresis/blood donors from Serbia were typed for 8 HPA systems (HPA-1 to HPA-6, HPA-9, and HPA-15) via the FluoGene method, based on polymerase chain reaction-sequence-specific amplification (PCR-SSP; PCR using sequence-specific primers) with fluorometric signal detection. Allele and genotype frequencies were estimated by direct counting and compared to the expected genotype frequencies according to the Hardy-Weinberg principle. The transfusion mismatch probability was calculated for every HPA specificity. RESULTS: The allele frequencies were: HPA-1a, 0.868; HPA-1b, 0.132; HPA-2a, 0.917; HPA-2b, 0.083; HPA-3a, 0.611; HPA-3b, 0.389; HPA-5a, 0.903; HPA-5b, 0.097; HPA-9a, 0.993; HPA-9b, 0.007; HPA-15a, 0.472; and HPA-15b, 0.528. For HPA-4 and HPA-6 only allele a was detected. DISCUSSION: The HPA allele frequencies of European populations showed no significant differences in comparison with our results. Statistically significant differences were revealed in comparison with some populations of non-European origin. In the tested donors no HPA-2 bb genotype was detected, but we found 1 donor with the rare HPA-9b allele. The biggest transfusion mismatch probability in the Serbian population is for systems HPA-15 (37.4%) and HPA-3 (36.2%), which means that more than a third of random transfusions could cause mismatch in these systems. This study was enabled by the introduction of molecular HPA typing, and it provides initial results of the HPA allele and genotype frequencies in the population of blood donors in Serbia. They will be used to provide a compatible blood supply on demand for treating patients with alloimmune thrombocytopenic disorders. The successful implementation of PCR-SSP with fluorometric signal detection could be further complemented in the future by the introduction of high-throughput methods, which will largely depend on the available financial resources.

Implementation of Molecular RHD Typing at Two Blood Transfusion Institutes from Southeastern Europe.

INTRODUCTION: Determination of RhD variants in blood donors, pregnant women, and newborns is important for transfusion strategies, in order to prevent RhD alloimmunisation and hemolytic disease of fetuses and newborns. Implementation of molecular RHD typing in two transfusion institutes is presented in this article, from Banja Luka (Bosnia and Herzegovina) and Belgrade (Serbia). STUDY DESIGN AND METHODS: Blood donors' RhD was checked by direct agglutination assays (tube) and indirect antiglobulin test (gel). Molecular RHD typing was performed by PCR-SSP with fluorometric signal detection in both centres. Donors were selected by weak RhD serological reactivity (Banja Luka, 85 samples; Belgrade, 62 samples) or serologically RhD-negative C/E-positive results (Banja Luka, 92 samples; Belgrade, 61 samples). RESULTS: Among serologically determined weak D donors from the institute from Banja Luka, weak D type 3 was the most frequent (58.8%), followed by type 1 (35.3%) and DNB (1.2%), whereas results obtained at the Belgrade institute were distributed between weak D type 1 (41.9%), type 3 (30.7%), type 14 (6.5%), type 15 (1.6%), and DNB with anti-D (1.6%). In 17.7% of serologically typed weak D samples from the Belgrade institute, the molecular typing result was standard D. Additionally, RHD presence was detected in 9.8% of serologically RhD-negative, C/E-positive samples from both institutes. CONCLUSION: Rh molecular testing was successfully implemented in both blood transfusion institutes in Banja Luka and Belgrade. This study proved the efficiency of serological algorithms for weak D, as well as the presence of the RHD gene among serologically tested RhD-negative, C/E-positive samples.

A successful outcome of pregnancy in a patient with congenital antithrombin deficiency.

BACKGROUND: Presence of inherited thrombophilia is an additional risk factor for maternal thromboembolism and certain adverse pregnancy outcomes, including recurrent fetal loss, placental abruption, intrauterine growth restriction and early-onset severe preeclampsia. Pregnant women with thrombophilia, especially those with antithrombin (AT) deficiency, are at high risk of both kinds of complications. CASE REPORT: We presented a pregnant women with congenital antithrombin deficiency in the first pregnancy, whose mother had had four times pregnancy-related deep vein thrombosis, and antithrombin deficiency. With the regular laboratory monitoring of hemostatic parameters and gynaecology surveillance including the follow-up of placental vascular flow, the whole pregnancy proceeded without complications. The prophylactic therapy with low molecular weight heparin was introduced from the 20th week of gestation and one dose of substitution therapy with antithrombin concentrate was administrated before delivery. Pregnancy and labour were terminated without complications at the 37th week of gestation, resulting in the delivery of a healthy male newborn of 3.6 kg body weight, 52 cm long, and with the Apgar scores of 9/10. CONCLUSION: A timely made diagnosis of thrombophilia, accompanied with regular obstetrics check-ups and follow-ups of hemostatic parameters during pregnancy, as well as the use of adequate prophylactic and substitution therapy, are the successful tools for the prevention of possible maternal complications and pregnancy itself in our patient with congenital AT deficiency.

The use of D-dimer with new cutoff can be useful in diagnosis of venous thromboembolism in pregnancy.

OBJECTIVE: D-dimer testing has an important role in the exclusion of acute venous thromboembolism (VTE) in the nonpregnant population. Establishing D-dimers role in the diagnosis of VTE in pregnancy is hampered because of the substantial increase of D-dimer throughout gestational age. STUDY DESIGN: In a prospective study we followed 89 healthy pregnant women to establish the reference range of D-dimer for each trimester. D-dimer testing was also performed in 12 women with clinical suspicion of VTE and their results were compared with the established new reference range of D-dimer, and with the recorded ultrasound findings. RESULTS: In the first trimester, 84% women from reference group had normal D-dimer, in the second 33%, and by the third trimester only 1%, which suggests that D-dimer has no practical diagnostic use in ruling out VTE if the threshold of 230 ng/mL for abnormal is used. All pregnant women with thrombosis who had positive ultrasound findings also had statistically significant elevation of the D-dimer level, considering the established reference range of the corresponding trimester. We found 100% sensitivity of D-dimer test. A women developed thrombosis in the first trimester had 6.7-7.6 time higher level of D-dimer than the mean value in the reference group, and in the third trimester thrombotic women had 2.0-3.8 time higher level of D-dimer, p<0.0001. CONCLUSION: D-dimer test with the new threshold for: the first of 286, the second of 457 and the third trimester of 644 ng/mL can be useful in diagnosis of pregnancy related VTE.