Iris Colon

Genotyping of Toxoplasma gondii by Multiplex PCR and Peptide-Based Serological Testing of Samples from Infants in Poland Diagnosed with Congenital Toxoplasmosis

ABSTRACT Toxoplasma gondii has a clonal population genetic structure with three (I, II, and III) lineages that predominate in North America and Europe. Type II strains cause most cases of symptomatic human infections in France and the United States, although few other regions have been adequately sampled. Here we determined the parasite genotype in amniotic fluid and cerebrospinal fluid samples from congenital toxoplasmosis cases in Poland. Nineteen confirmed congenital cases of toxoplasmosis were analyzed, including both severe and asymptomatic cases. The genotype of parasite strains causing congenital infection was determined by direct PCR amplification and restriction fragment length polymorphism analysis. Nested multiplex PCR analysis was used to type four independent polymorphic markers. The sensitivity of multiplex nested PCR was ≥25 parasites/ml in amniotic fluid and cerebral spinal fluid samples. Parasite DNA was successfully amplified in 9 of 19 samples (eight severely affected and one asymptomatic fetus). Only genotype II parasites were identified as the source of T. gondii infection based on restriction fragment length polymorphism analysis. Strains causing congenital infections were also typed indirectly based on detection of antibodies to strain-specific peptides. Serotyping indicated that 12 of 15 cases tested were caused by type II strains and these positives included both symptomatic and asymptomatic infections. Overall, the combined analysis indicated that 14 of the cases were caused by type II strains. Our results are consistent with the hypothesis that parasite burden is associated with severity of congenital toxoplasmosis and indicate that serological testing provides a promising method for genotypic analysis of toxoplasmosis.

Outcome of pregnancies complicated by systemic sclerosis and mixed connective tissue disease

Systemic sclerosis (SSc) and mixed connective tissue disease (MCTD) are rare autoimmune diseases which share the common feature of non-inflammatory vasculopathy. Studies evaluating pregnancy outcomes in these patients have yielded conflicting results. We sought to describe the outcomes of pregnancies associated with SSc and MCTD followed at our center utilizing a retrospective review of all pregnant women with SSc and MCTD followed at Stanford University from 1993 to 2003. We identified 20 pregnancies occurring in 13 women with SSc or MCTD. Twelve pregnancies occurred in seven women with SSc and eight pregnancies occurred in six women with MCTD. The overall preterm delivery rate was 39% and small for gestational age infants occurred in 50% and 63% of pregnancies associated with SSc and MCTD, respectively. Fetal loss complicated two pregnancies in women with severe diffuse SSc and the antiphospholipid antibody syndrome. There were no cases of congenital heartblock among infants, and only one case of pre-eclampsia was observed. Maternal flares of disease during pregnancy were generally mild. Most pregnancies in women with SSc and MCTD in this cohort were uncomplicated. The high rates of prematurity and small for gestational age infants underscore the risk for growth restriction consistent with the vasculopathy associated with these diseases.

Randomized, Double-Blinded Trial of Magnesium Sulfate Tocolysis versus Intravenous Normal Saline for Preterm Nonsevere Placental Abruption

Objective To evaluate the efficacy and safety of magnesium sulfate in the resolution of vaginal bleeding and contractions in nonsevere placental abruption. Study Design Thirty women between 24 and 34 weeks of gestation diagnosed with nonsevere placental abruption were randomized to receive magnesium sulfate tocolysis or normal saline infusion. The primary outcome was the proportion of women undelivered at 48 hours with resolution of vaginal bleeding and uterine contractions. Maternal and neonatal outcomes were also compared. Results Fifteen (50%) women received magnesium sulfate tocolysis and 15 (50%) received intravenous saline. There was no difference in the number of women who were undelivered at 48 hours with resolution of vaginal bleeding and contractions in the magnesium sulfate (80.0%) and saline (66.7%; p-value = 0.68) groups. There were no differences between groups in the gestational age at randomization, time to uterine quiescence, time on study drug, length of hospitalization, days from randomization to delivery, incidence of side effects, or admissions to the neonatal intensive care unit. Conclusions Magnesium sulfate tocolysis did not provide a significant difference in pregnancy prolongation in the management of preterm nonsevere placental abruption. Recruitment goals were not met due to the introduction of the use of magnesium sulfate for neuroprotection.