RISK FACTORS ASSOCIATED WITH SEROPREVALENCE OF TOXOPLASMA GONDII AMONG RENAL FAILURE PATIENTS

BackgroundWhen a pregnant woman contracts Toxoplasma gondii (T. gondii) infection during pregnancy, it may be vertically transmitted to the foetus. Information on the incidence of congenital toxoplasmosis (CT) in developing countries is scarce. Most studies focus on the seroprevalence of T. gondii infection among pregnant women. This study aimed to determine the seroprevalence of T. gondii infection among pregnant women attending public antenatal care in Windhoek, Namibia, in 2016.MethodsIn this descriptive study, 344 urban pregnant women attending public antenatal care were voluntarily enrolled in the study. Seroprevalence of anti-T. gondii Immunoglobulin G (IgG) was determined by automated immunoassay. Samples with a positive T. gondii IgG result were tested for T. gondii Immunoglobulin M (IgM) and specific IgG avidity by using an enzyme-linked immunosorbent assay (ELISA) test. A questionnaire captured demographic data and exposure to risk factors. Data were analysed using Statistical Package for the Social Sciences (SPSS) and R.ResultsAnti-T. gondii IgG was found in nine (2.61%) pregnant women. There was no association of anti-T. gondii IgG with demographic characteristics or exposure to risk factors.Anti-T. gondii IgM was positive in one (0.3%) woman, while three (0.9%) women had borderline anti-T. gondii IgM results. Specific IgG avidity was low, equivocal and high in 0%, 33% and 67% of seropositive pregnant women, respectively.ConclusionSeroprevalence of anti-T. gondii IgG is much lower in Namibia than is reported in other developing countries. Investigation into specific IgM seropositivity and IgG avidity showed that pregnant women in the central region of Namibia are at low risk of vertical transmission and development of CT.

Neurofilaments are cytoskeletal proteins localized within axons, which may interact with the immune system during and following tissue destruction in multiple sclerosis (MS). Antibodies against the medium neurofilament subunit synthesized intrathecally may reflect axonal damage in MS patients. Both immunoglobulin G (IgG) and M (IgM) responses against the purified native medium subunit of neurofilaments (NFM) using enzyme-linked immunosorbent assay (ELISA) were determined in paired serum and cerebrospinal fluid samples obtained from 49 MS patients, 16 normal controls (CN), 21 control patients with miscellaneous diseases (CD) and 14 patients with neurodegenerative disorders (CDEG). Intrathecal production of IgM and IgG antibodies to NFM were elevated in MS patients compared with the CN or CD groups (p<0.04 for IgM, p<0.01 for IgG). The increase was present in all the MS courses (relapsing-remitting, primary and secondary progressive). Similar local anti-NFM IgG and IgM synthesis occurred in the MS and CDEG groups. MS patients with short and long disease duration did not differ in terms of their anti-NFM IgM and IgG responses. Repeated examinations showed stable intrathecal anti-NFM production. Intrathecal IgG and IgM antibodies against NFM were increased in MS patients and may serve as a potential marker for axonal pathology. The extent of anti-NFM levels did not correspond to any individualized clinical profiles of MS patients.

Background: Acute Toxoplasma gondii infection during pregnancy period can cause congenital toxoplasmosis. The aim of this study was to assess the seroprevalence rate of immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies against T. gondii infection during pregnancy and the associated risk factors in southwest Iran. Methods: This study was performed on 88 pregnant women from October to December 2019 in Khorramshahr County, Khuzestan province, Iran. Anti-T. gondii IgG and IgM antibodies were tested through enzyme-linked immunosorbent assay (ELISA) method. Results: Following serological assays, 38.63% (34/88) and 2.27% (2/88) serum samples were positive for IgG and IgM antibodies, respectively. Also, a statistically significant association was observed between IgG seroprevalence and drinking of unpurified water (P = 0.015). Conclusions: The serological evidence revealed that pregnant women of southwest Iran had moderate exposure to T. gondii parasite. Since the risk of acquiring acute toxoplasmosis in pregnant women is clinically important, we highly recommend regular screening tests for T. gondii infection during pregnancy period.

The clinical evidence, complications and the pathogenesis of COVID-19 are not clearly understood. In COVID-19 patients, cellular immune response biomarkers and oxidative stress parameters have been used as gravity markers. Indeed, oxidative stress has been proposed to play an essential role in the genesis of COVID-19. In the present research, we investigated lipid peroxidation, protein oxidation, superoxide dismutase activity and the production of auto-antibodies against superoxide dismutase, in the blood of Tunisian patients with corona virus. To evaluate lipid peroxidation, plasma malondialdehyde and conjugated dienes, have been determined in 69 corona virus patients and 30 controls. To determine protein oxidation the thiol level was measured. Plasma superoxide dismutase activity has been measured in 30 corona virus patients and 30 controls on one hand. Utilizing a standard enzyme-linked immunosorbent assay, the level of immunoglobulin G (IgG), and M (IgM) directed against superoxide dismutase was evaluated. To investigate the implication of auto-antibody production in COVID-19 patients in the generation of oxidative stress, a correlation study between auto-antibodies production and oxidative stress parameters was performed. High levels of both malondialdehyde and conjugated dienes were found in the plasma of patients (p < 0.001, respectively). Protein oxidation was confirmed by the high level of thiol (p < 0.001). Superoxide dismutase activity was not significantly lower in COVID-19 patients (p > 0.05). The level of immunoglobulin G (IgG), and M (IgM) directed against superoxide dismutase is significantly higher in COVID-19 patients than in control group (p < 0.001 respectively). Statistical analyses have demonstrated a positive correlation between superoxide dismutase activity and IgM and IgG isotypes antibodies level against superoxide dismutase (p < 0.001). A strong positive correlation was observed between IgG and malondialdehyde level in all cases (r = 0.368; p ≤ 0.01). In addition, a significant positive correlation was noted between IgM and malondialdehyde (r = 0.290; p = 0.024). Similarly, two significant positive relationship was found between IgG / conjugated dienes (r = 0.356; p = 0.005) and between IgM / conjugated dienes (r = 0.285; p = 0.027).

BackgroundDexamethasone is currently administered for Coronavirus disease 2019(COVID-19); however, there are concerns about its effect on specific antibodies’ production. The aim of this study was to evaluate whether specific antibodies were affected by COVID-19 severity and corticosteroid treatment.MethodsOf 251 confirmed COVID-19 patients admitted to our hospital between January 26 and August 10, 2020, the early period of the pandemic, 75 patients with sera within 1 month of onset and 1 month or longer were included in the research. A total of 253 serum samples from these patients were collected. The levels of specific antibodies for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2), immunoglobulin G (IgG) and M (IgM), were measured retrospectively. The results were compared separately of each COVID-19 severity, and with or without corticosteroid treatment.ResultsAmong the 75 patients, 47, 18, and 10 had mild, moderate, and severe disease, respectively. The median age was 53.0 years and 22 (29%) were women. The most common comorbidities were hypertension and dyslipidemia. Corticosteroids were administered to 20 (27%) and 10 (53%), patients with moderate and severe disease, respectively. The positivity rates IgM increased first, and IgG was almost always positive after day 16, regardless of the severity of COVID-19. On days 6–10, both IgG and IgM positivity rates were higher in patients with moderate disease than in those with mild or severe disease. In patients with moderate disease, IgG positivity was similar over time, regardless of corticosteroid treatment.ConclusionsIn COVID-19 patients, specific IgG is positive and maintained for a long period of time, even after corticosteroid treatment. The effect of corticosteroid treatment in a COVID-19 epidemiological study using specific IgG antibodies was considered minor. COVID-19 patients were more likely to receive oxygen if IgM was positive 1 week after onset, but not mechanical ventilation. IgM measurement 1 week after onset may predict COVID-19 severity.

O objetivo deste estudo foi determinar a ocorrência de anticorpos anti-Neospora caninum em 260 amostras de soro coletadas de fetos bovinos de julho de 2007 a março de 2008, em abatedouro do município de Santa Maria, Rio Grande do Sul, Brasil. Para detecção de anticorpos anti-N. caninum, a técnica de imunofluorescência indireta foi utilizada tanto para a detecção de imunoglobulinas G e M. Amostras com títulos e" 25 foram consideradas positivas. Das 260 amostras testadas, 15% (39/260) foram positivas para anticorpos anti-N. caninum. Destas, em 38 (97,4%) foi detectada a presença de IgG anti-N. caninum e em seis (15,4%) de IgM. Em cinco amostras (12,8%) detectaram-se ambos, IgG e IgM. Os resultados reafirmam a habilidade do N. caninum em determinar infecção fetal. A pesquisa de IgM foi de limitada importância na detecção da infecção via transplacentária em soro fetal bovino.

Background:Parvovirus B19 is a common viral infection in children. Nearby evidences are present about its association with acute leukemia, especially acute lymphoblast leukemia. Nevertheless, scanty reports have discussed any role in acute myeloid leukemia (AML).Purpose:To evaluate the frequency of virological markers of B19 infection including its DNA along with specific immunoglobulins G (IgG) and M (IgM) among children with newly diagnosed AML. Besides, describing the clinical importance of Parvovirus B19 infection in those patients.Patients and methods:A case-control retrospective study was conducted on 48 children recently diagnosed with AML before and during chemotherapy induction and 60 healthy control. Specific serum IgM and IgG levels were determined by enzyme linked immunosorbant assay (ELISA) and DNA detection by polymerase chain reaction (PCR).Results:Parvovirus DNA was detected in 20 patients with AML. IgM was found in sera of four patients and one case had positive DNA and IgG (5%). Patients with recent parvovirus B19 infection had a significantly reduced hemoglobin levels, RBCs counts, platelet counts, neutrophil counts and absolute lymphocytosis (p=0.01, p=0.0001, p=0.01, p=0.02, p=0.0003, respectively). There were no clinical findings with statistically significant association to recent infection. Half of the patients with AML had positive PCR and/or IgM for parvovirus B19. Among children with AML under chemotherapy, there were reduced hemoglobin levels (P=0.03), reduced platelet counts (P=0.0001) and absolute neutropenia (mean±SD, 1.200 ±1.00) in those with parvovirus B19 infection. More than half of patients with parvovirus B19 (72.2%) had positive PCR and/or IgM and 36.4% of them had positive IgG.Conclusion:This study highlights that parvovirus B19 is common in children with AML either at diagnosis or under chemotherapy. There are no clinical manifestations that can be used as markers for its presence, but hematological laboratory findings can provide evidence for infection in the presence of anemia and neutropenia. Detection of parvovirus B19 by combined molecular and serological markers is required in such patients for accurate diagnosis.

BackgroundToxoplasmosis is an infectious disease caused by a protozoan parasite named Toxoplasma gondii (T.gondii). Pregnant women are considered one of the risk groups. The objective of this retrospective study is to provide an updated estimate of the seroprevalence of anti-T. gondii antibodies among a group of Moroccan pregnant women monitored at the Parasitology Laboratory of the National Institute of Hygiene in Rabat in Morocco.MethodsSerum samples were tested for the presence of specific anti-T. gondii immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies using indirect enzyme-linked immunosorbent assay (ELISA). Anti-Toxoplasma IgM- and IgG-positive cases were also evaluated with the anti-Toxoplasma IgG avidity test. All cases were evaluated according to the age, parity, and historical of abortion.ResultsAmong 677 pregnant women, 94.1% (637/677) were serologically screened for the first time and therefore had no knowledge of their serological status, and only 5.9% (40/677) were screened for the second or third time. The overall anti-T. gondii IgG and IgM seropositivity among the 637 pregnant women included in the study analysis was 43% (274/637) and 3.9% (25/637), respectively. The use of the IgG avidity test allowed excluding recent infection among 83% of cases with IgG and IgM positive sera. The mean age was 29.4 ± 6.3 years. The result of the bivariate analysis revealed that the age influenced significantly the seroprevalence rate, while the parity and the existence of previous spontaneous abortion did not have any significant statistical correlation with seropositivity to T. gondii.ConclusionThis study shows that 43% of pregnant women were positive and 57% of them had no antibody against the T. gondii infection. However, the pregnancy follow-up and the counseling of pregnant women remain essential for the prevention of congenital toxoplasmosis.

Toxoplasmosis is a worldwide disease caused by Toxoplasma gondii, which can infect diverse hosts, including dogs. Although T. gondii infection in dogs is usually subclinical, they are susceptible to infection and develop a specific immune response to the parasite. In 2018, the largest outbreak of human toxoplasmosis in the world occurred in Santa Maria, in southern Brazil; however, the impact of this outbreak on other hosts was not investigated at the time. Considering that dogs often share the same environmental sources of infection as humans, mainly water sources, and that in Brazil, the detection rates of anti-T. gondii immunoglobulin G (IgG) in dogs is very high, this study investigated the frequency of anti-T. gondii IgG in dogs in Santa Maria before and after the outbreak. A total of 2.245 serum samples were analyzed, 1159 collected before the outbreak and 1086 collected after the outbreak. Serum samples were tested for anti-T. gondii antibodies using an indirect immunofluorescence antibody test (IFAT). The infection detection of T. gondii was 16% (185/1159) before the outbreak and 43% (466/1086) after the outbreak. These results showed the infection of dogs with T. gondii and the high frequency of anti-T. gondii antibodies in dogs after the outbreak in humans in 2018, reinforcing water as a possible source of infection and the importance of including toxoplasmosis in the differential diagnosis of dogs.

Toxoplasma gondii, the causative agent of toxoplasmosis, is a zoonotic obligate intracellular protozoan parasite responsible for the infection of almost one-third of the world's population. T. gondii is particularly threatening for primo-infected pregnant women and may lead, following vertical transplacental transmission, to spontaneous abortion, miscarriage, or severe manifestations in the newborn. The aim of this study was to provide an updated estimate of the seroprevalence of anti-T. gondii antibodies among a group of Lebanese pregnant women and its seroconversion rate. This is a retrospective cohort study, in which medical records of 11,000 pregnant women were screened. These women visited a private Obstetrics and Gynecology clinic located in Beirut, the capital of Lebanon, during the period of January 1994 till September 2015. Serological results of anti-T. gondii immunoglobulin G (IgG) and immunoglobulin M (IgM) results of 2456 Lebanese pregnant women who fulfilled the inclusion criteria were included in the analysis. Seropositivity and seroconversion rates for women with repeated tests were reported according to age and area of residence. The overall anti-T. gondii IgG and IgM seropositivity among 2456 Lebanese pregnant women was 82.6% and 1.8% respectively. The highest IgG seropositivity is among the age group of 35-44 years (87.81%) and at the governorate of "Mount Lebanon" (82.95%). Sixty-four seroconversions were detected and two abortions due to T. gondii infection during pregnancy were recorded. The seroprevalence of anti-T. gondii IgG among the screened pregnant women in Lebanon is the highest in the Arab region. These results highlight the importance of running a national sample survey to estimate the real potential burden of this infection and its impact on maternal and fetal health.

Infection is a significant cause of morbidity and mortality in patients with chronic kidney disease, especially who were under dialysis due to their depressed immunity. Toxoplasma gondii is a ubiquitous parasite that causes severe manifestations in immunocompromised patients. This case-control study was conducted to the immunodiagnosis and molecular validation of T. gondii infection among patients with end-stage renal disease undergoing haemodialysis. The study population consisted of 260 haemodialysis patients and 259 healthy controls referred to the main dialysis centres of Tehran, Iran during 2016. Anti-T. gondii immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies were assessed using enzyme-linked immunosorbent assay. As well, the T. gondii genomic DNA in whole blood samples of IgM-positive patients and healthy controls was evaluated using GRA6-polymerase chain reaction (PCR) and SAG1-loop-mediated isothermal amplification (LAMP) assays. The anti-T. gondii IgG and IgM antibodies were detected in 175 (67.3%) and 18 (7%) of haemodialysis patients and 122 (47%) and 4 (1.5%) of controls, respectively. Two of the 18 blood samples from IgM-positive patients and none of the IgM-positive control subjects were positive by GRA6-PCR. Whereas, nine and two blood samples of IgM-positive patients and controls were positive for Toxoplasma DNA by a SAG1-LAMP technique respectively. The seropositivity of the Toxoplasma IgM antibody was significantly different between haemodialysis patients and healthy controls which was confirmed by PCR and LAMP. The higher prevalence of T. gondii infection in haemodialysis patients compared with the controls proposes that these patients can be a group at risk for toxoplasmosis and screening for toxoplasmosis before dialysis is necessary for the patients.

BackgroundBrucellosis, coxiellosis, and toxoplasmosis can be transmitted from infected ruminants to pregnant women and may induce adverse pregnancy outcomes; however, there are to date few studies. This study aimed to examine the seropositivities of immunoglobulin G (IgG) against those three pathogens among pregnant women with adverse pregnancy outcomes, and to explore the associated factors.MethodsA cross-sectional study was conducted in southern Thailand, where goat production is common. A total of 105 pregnant Thai women who had adverse pregnancy outcomes and serum samples collected at first antenatal care visit before their 28th gestational week from June 2015 to June 2016 were included. The seropositivities of IgG anti-Brucella abortus, Toxoplasma gondii, and Coxiella burnetii antibodies were tested by using commercial enzyme-linked immunosorbent assay (ELISA) kits. Associated factors with seropositivity were analyzed using multiple logistic regression.ResultsMost women were Muslim aged 20–34 years and 32.4% had a prior history of one or more adverse pregnancy outcomes. One-third of the women had been exposed to goats or raw goat products. Of the 105 serum samples, the seropositivity of anti-T. gondii IgG was highest (33/105, 31.4%), followed by anti-C. burnetii IgG (2/105, 1.9%), and anti-B. abortus IgG (1/105, 1.0%), respectively. None of the pregnant women were found to be co-seropositive for those three pathogens.ConclusionsOne-third of women with adverse pregnancy outcomes showed positive antibodies for toxoplasmosis, coxiellosis and brucellosis. A dose-response relationship between seropositivity of anti-T. gondii IgG and age was noticed.

Macro lactate dehydrogenase: An LDH-immunoglobulin M complex that inhibits lactate dehydrogenase activity in a patient's serum

The aim of the study was to determine the prevalence of hepatitis E virus (HEV) infection among individuals at high risk of transmission of non-A, non-B hepatitis or sexually transmitted diseases (STDs), and to evaluate whether they have an increased risk of exposure to HEV. Serum samples from 125 thalassemia patients, 300 intravenous drug users, 420 hemodialysis patients, 263 individuals with STDs, 47 human immunodeficiency virus (HIV) infected homosexual men, and 316 healthy volunteers were tested for immunoglobulin G (IgG) and M (IgM) antibodies to HEV (anti-HEV) by enzyme immunoassays (EIAs) following a predetermined algorithm (Abbott Labs). Anti-HEV IgG was confirmed in 3/125 (2.4%) thalassemia patients, 5/300 (1.7%) intravenous drug users, 27/420 (6.4%) hemodialysis patients, 4/263 (1.5%) STD patients, 1/47 (2.1%) homosexual men, and 7/316 (2.2%) of the reference group. No patient was found positive for anti-HEV IgM. The higher prevalence which was observed in hemodialysis group was due to the confounding effect of age, as multivariate analysis showed. The anti-HEV prevalence increased significantly with age (p = 10(-4)). No significant association was found between anti-HEV, anti-HCV, and anti-HBc. In conclusion, individuals at high risk of non-A, non-B hepatitis and STDs have no increased risk of exposure to HEV and the higher prevalence of anti-HEV IgG among older subjects may be due to an epidemic form of HEV infection which occurred some decades ago, when the sanitary conditions in our country were poor.

The lower burden of COVID-19 in tropical settings may be due to preexisting cross-immunity, which might vary according to geographical locations and potential exposure to other pathogens. We sought to assess the overall prevalence of SARS-CoV-2 antibodies and determine SARS-CoV-2 seropositivity according to HIV-status before the COVID-19 pandemic era. A cross-sectional and comparative study was conducted at the Chantal BIYA International Reference Centre (CIRCB) on 288 stored plasma samples (163 HIV-positive versus 125 HIV-negative); all collected in 2017-2018, before the COVID-19 pandemic era. Abbott Panbio™ COVID-19 IgG/IgM assay was used for detecting SARS-CoV-2 immunoglobulin G (IgG) and M (IgM). Among people living with HIV (PLHIV), HIV-1 viral load and TCD4 cell count (LTCD4) were measured using Abbott Real Time PCR and BD FACSCalibur respectively. Statistical analyses were performed, with p<0.05 considered statistically significant. The median [IQR] age was 25 [15-38] years. Overall seropositivity to SARS-CoV-2 antibodies was 13.5% (39/288) of which 7.3% (21) was IgG, 7.3% (21) IgM and 1.0% (3) IgG/IgM. According to HIV-status in the study population, SARS-CoV-2 seropositivity was 11.0% (18/163) among HIV-positive versus 16.8% (21/125) among HIV-negative respectively, p=0.21. Specifically, IgG was 6.1% (10/163) versus 8.8% (11/125), p=0.26; IgM was 5.5% (9/163) versus 9.6%, (12/125), p=0.13 and IgG/IgM was 0.6% (1/163) versus 1.6% (2/125) respectively. Among PLHIV, SARS-CoV-2 seropositivity according to CD4 count was 9.2% (≥500 cells/µL) versus 1.8% (200-499 cells/µL), (OR=3.5; p=0.04) and 0.6% (<200 cells/µL), (OR=17.7; p<0.01). According to viral load, SARS-CoV-2 seropositivity was 6.7% (≥40 copies/mL) versus 4.9% (<40 copies/mL), (OR= 3.8; p<0.01). Before COVID-19 in Cameroon, cross-reactive antibodies to SARS-CoV-2 were in circulation, indicating COVID-19 preexisting immunity. This preexisting immunity may contribute in attenuating disease severity in tropical settings like Cameroon. Of relevance, COVID-19 preexisting immunity is lower with HIV-infection, specifically with viral replication and poor CD4-cell count. As poor CD4-count leads to lower cross-reactive antibodies (regardless of viral load), people living with HIV appear more vulnerable to COVID-19 and should be prioritized for vaccination.