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Background: Information on tick-borne encephalitis (TBE) in patients already vaccinated against the disease is limited.Objectives: To compare the course and outcome in patients with vaccination breakthrough TBE with findings in patients who developed TBE without previous vaccination.Methods: All adult patients diagnosed with TBE at a single medical centre during a 16-year period and who had received at least two doses of TBE vaccine before the onset of illness qualified for the study. For each patient with breakthrough TBE, two unvaccinated sex- and age-matched patients, diagnosed with TBE in the same year, were included for comparison.Results: Amongst 2332 patients diagnosed with TBE in the period 2000-2015, 39 (1.7%) had been vaccinated against the disease. Their median age was 59 (20-83) years; 22 of 39 (56.4%) were male. In comparison with unvaccinated patients with TBE, those with breakthrough disease more often experienced a monophasic course of illness (P = 0.006), had a higher CSF leucocyte count (P = 0.005), more often had urine retention (P = 0.012), more often needed ICU treatment (P = 0.009), were hospitalized for longer (P = 0.002) and had more severe acute illness (P = 0.004 for simple clinical assessment, P = 0.001 for severity score).Conclusion: In addition to several findings corroborating previous results in patients with vaccination breakthrough TBE, such as older age and the presence of a particular specific serum antibody pattern indicating anamnestic response, findings in this study indicate that the acute illness in patients with breakthrough TBE is more severe than in unvaccinated sex- and age-matched patients who develop the disease. [ABSTRACT FROM AUTHOR]

Key Content: Cytomegalovirus (CMV) is the most common cause of congenital viral infections; 75–90% of infections are asymptomatic at birth but 10–25% of infants will develop neurological sequelae.Diagnosis of primary maternal CMV in pregnancy should be based on seroconversion in pregnancy (de novo appearance of virus‐specific immunoglobulin G [IgG] in the serum of pregnant women who were previously seronegative) or on detection of specific immunoglobulin M (IgM) and IgG antibodies in association with low IgG avidity.Primary maternal infection is associated with a 30–40% risk of intrauterine transmission and fetal infection, with 20–25% of those infected developing sequelae postnatally.Prenatal diagnosis of fetal CMV is imperfect and based on amniocentesis performed at least 7 weeks after presumed maternal infection and after 21 weeks of gestation.The presence of radiologic findings by ultrasound in combination with CMV DNA viral load in amniotic fluid may have prognostic significance for risk of neurologic sequelae. Learning objectives: To understand the prevalence, diagnosis and implications of CMV infection in pregnancy.To explore the management options in a pregnancy affected by congenital CMV. Ethical issues: Should routine screening for CMV be recommended in pregnancy?How should termination counselling be conducted following prenatal confirmation of fetal infection with amniocentesis? [ABSTRACT FROM AUTHOR]

Following primary human cytomegalovirus (HCMV) infection, virus-specific IgG antibody shift from low to high avidity with individual variations in the rate of avidity maturation. The kinetics of the avidity maturation of IgG specific for HCMV nuclear antigen in pregnant women with primary infection was investigated. Absorbance values used for avidity index calculation of 286 sequential sera collected from 69 pregnant women with primary HCMV infection were retrieved. Percent difference in absorbance values of IgG antibody bound to the solid phase after urea treatment (IgG avidity) between early (T1, 0-90, median 31 days) and late (T2, 91-180, median 136 days) serum samples was calculated for each woman. Three groups of women were identified: 24/69 (34.8%) women showed high (>100%) avidity increase between T1 and T2 (pattern H), 29/69 (42%) low (<50%) increase (pattern L), and 16/69 (23.2%) intermediate increase (pattern I). Avidity values in T1 samples were significantly higher in women with pattern L compared to women with pattern H ( P = 0.01). Altogether, 28/69 (40.6%) women transmitted HCMV infection to their fetuses. Fetal infection preferentially occurred ( P < 0.01) in women with pattern H (15/24, 62.5%) compared with women with pattern L (7/29, 24.1%). In conclusion, different patterns of IgG avidity maturation can be detected following primary HCMV infection. Pregnant women with pattern H (rapid IgG avidity increase) appear to be at higher risk for fetal infection, whereas, pregnant women developing early antibody with high avidity appear to be at a lower risk of vertical transmission. J Med. Virol. 85:1960-1967, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

We encountered a woman whose infant developed congenital toxoplasmosis. Serum Toxoplasma gondii antibody titers (320×) at 12 weeks of gestation increased to 5120× at 25 weeks. Toxoplasma immunoglobulin M was 2.8 index, and immunoglobulin G avidity index was 23%. Cyclic administration of acetylspiramycin was maintained from 22 weeks until delivery. Multiplex-nested polymerase chain reaction of maternal blood and amniotic fluid at 28 weeks both tested positive for Toxoplasma DNA. A male neonate weighing 2916 g was born at 38 weeks via cesarean section. No abnormalities were detected by physical and funduscopic examinations, whereas a head computed tomography of the neonate revealed three independent intracranial calcifications. The infant underwent therapy with pyrimethamine and sulfadiazine for one year. Serum titers of Toxoplasma gondii antibodies were all less than cut-off values between 5 and 12 months after birth, but all increased up to positive levels 18 months after birth. [ABSTRACT FROM AUTHOR]

Human toxocariasis is a zoonosis caused by infection with larvae of the ascarid nematode Toxocara canis and, less frequently, T. cati . Our study developed a method for distinguishing distant from recent human toxocariasis by assessing the avidity of the IgG antibodies. The avidity of specific antibodies increases with time after antigen challenge and assessment of the degree of avidity can be used to discriminate between recent and distant infections. The relative avidity was measured in 150 sera from children with visceral toxocariasis and in 46 sera from children with ocular toxocariasis. The probable time of infection was estimated on the basis of the medical history and clinical syndrome. Our study showed that 94·2% of positive sera collected from patients reporting infection > 6 months ago had high IgG avidity values, confirming distant toxocariasis, whereas 25·9% of positive sera taken < 6 months after infection showed low indices of IgG avidity. Our results suggest that measurement of the specific IgG avidity may assist in discriminating between recent and distant toxocariasis. The method can be used effectively to rule out (because of high avidity) a recently acquired infection. Low avidity is less reliable in discriminating between recent and distant infections. [ABSTRACT FROM AUTHOR]

PROBLEM: Toxoplasmosis is a major cause of congenitally acquired infections causing high degree of morbidity and mortality in the newborns. METHODS OF STUDY: IgG avidity method was used to distinguish the recent and more than 4 months old infection in a prospective cohort study for the first time in India. One hundred and eighty pregnant women presented in their first 4 months of pregnancy were included in this study. Their sera were tested for anti-Toxoplasma gondii antibodies using direct agglutination test, immunoglobulin (Ig)G and IgM-enzyme-linked immunosorbent assay, IgM-immunosorbent agglutination assay and VIDAS-IgG avidity. RESULTS: Overall IgG seroprevalence rate of toxoplasmosis was 45%. Only seven women (3.3%)were found to have IgM antibodies and only two of these showed low IgG avidity indicating recent infection of ≤4 months duration. One woman aborted spontaneously at her fourth month of gestation. In remaining five women the recent infection could successfully be excluded by IgG avidity testing. All these women had uneventful pregnancy. CONCLUSIONS: This study indicated that all IgM antibody positive pregnant must be tested for IgG avidity to rule out recent primary infection. [ABSTRACT FROM AUTHOR]

Guisasola ME, Ramos B, Sanz JC, García-Bermejo I, de Ory Manchón F. Comparison of IgG avidity assays in the confirmation of the diagnosis of cytomegalovirus primary infection. APMIS 2010; 118: 991-3. We have compared three ELISA techniques and one chemiluminescence immunoassay technique for determining cytomegalovirus (CMV) immunoglobulin G (IgG) avidity in serum samples from patients with recent and past CMV infections. Sensitivity varied from 84.6% to 100%; and specificity from 78.6% to 100%. IgG avidity assays appear to be adequate additional tools for characterizing CMV infections. [ABSTRACT FROM AUTHOR]