Diversity and composition of vaginal microbiota of pregnant women at risk for transmitting Group B Streptococcus treated with intrapartum penicillin.

BACKGROUND: Administering intravenous antibiotics during labor to women at risk for transmitting Group B Streptococcus (GBS) can prevent infections in newborns. However, the impact of intrapartum antibiotic prophylaxis on mothers' microbial community composition is largely unknown. We compared vaginal microbial composition in pregnant women experiencing preterm birth at ≤ 32 weeks gestation that received intrapartum antibiotic prophylaxis with that in controls. METHODS: Microbiota in vaginal swabs collected shortly before delivery from GBS positive women that received penicillin intravenously during labor or after premature rupture of membranes was compared to controls. Microbiota was analyzed by 16S rRNA sequencing using the PGM Ion Torrent to determine the effects of penicillin use during hospitalization and GBS status on its composition. RESULTS: Penicillin administration was associated with an altered vaginal microbial community composition characterized by increased microbial diversity. Lactobacillus sp. contributed only 13.1% of the total community in the women that received penicillin compared to 88.1% in the controls. Streptococcus sp. were present in higher abundance in GBS positive woman compared to controls, with 60% of the total vaginal microbiota in severe cases identified as Streptococcus sp. CONCLUSIONS: Vaginal communities of healthy pregnant women were dominated by Lactobacillus sp. and contained low diversity, while Group B Streptococcus positive women receiving intrapartum antibiotic prophylaxis had a modified vaginal microbiota composition with low abundance of Lactobacillus but higher microbial diversity.

Assessment of regulatory T cells in childhood immune thrombocytopenic purpura.

This study had the objective to assess the frequency of Tregs in children newly diagnosed with ITP and ascertain whether an association exists between Tregs and platelet counts, by means of a comparison with healthy controls. This case-control study included 19 patients newly diagnosed with ITP-whose blood samples were collected at four points in time: before any therapy and 1, 3, and 6 months after diagnosis-and 19 healthy controls. Tregs (CD4(+) CD25(+)Foxp3 T cells) were evaluated by flow cytometry. There was a statistically significant difference in platelet count between the case and control groups. There were no significant differences in Treg counts between cases and controls at any point during the course of the study and no difference in Treg counts between the chronic and nonchronic groups and no significant correlation between Tregs and platelet counts in the case and control groups. The findings of this study did not show any statistically significant correlation between Tregs and number of platelets in the case and control groups. Treg cells did not play a role in the regulation of autoimmunity in children with ITP.