Search

Inherited chromosomally integrated human herpesvirus 6 (iciHHV-6) is a condition in which the complete HHV-6 genome is integrated into the chromosomes of the host germ cell and is vertically transmitted. The aims of this study were to identify iciHHV-6 prevalence in hospitalized patients and clinical features in individuals carrying this integration. HHV-6 PCR on hair follicles was used to confirm iciHHV-6 status when the blood viral load was more than 5 Log10 copies/mL. From January 2012 to June 2022, HHV-6 DNAemia was investigated in 2019 patients. In particular, 49 had a viral load higher than 6 Log10 copies/mL and HHV-6 DNA in hair follicles was positive. A viral load between 5.0 and 5.9 Log10 copies/mL was observed in 10 patients: 6 infants with acute HHV-6 infection and 4 patients with leukopenia and HHV-6 integration. Therefore, the iciHHV-6 prevalence in our population was 2.6% (53/2019). Adult patients with integration presented hematological (24%), autoimmune (11%), autoimmune neurological (19%), not-autoimmune neurological (22%), and other diseases (19%), whereas 5% had no clinically relevant disease. Although in our study population a high percentage of iciHHV-6 adult hospitalized patients presented a specific pathology, it is still unknown whether the integration is responsible for, or contributes to, the disease development.

The inhabitants of the vaginal ecosystem can harbor genetic determinants conferring antimicrobial resistance. However, detailed data about the distribution of resistance genes in the vaginal microbiome of pregnant women are still lacking. Therefore, we assessed the presence of macrolide (i.e., erm genes) and tetracycline (i.e., tet genes) resistance markers in the vaginal environment of Caucasian women at different gestational ages. Furthermore, the detection of resistance genes was related to the composition of the vaginal microbiota. A total of 228 vaginal samples, collected at different trimesters of pregnancy or during the puerperium, were tested for the presence of ermB, ermF, tet(W), and tet(M) by in-house end-point PCR assays. The composition of the vaginal microbiota was assessed through a microscopic evaluation (i.e., Nugent score) and by means of sequencing V3–V4 hypervariable regions of the bacterial 16 rRNA gene. Overall, the most detected resistance gene was tet(M) (76.7%), followed by ermB (55.2%). In 17% of women, mainly with a ‘normal’ vaginal microbiota, no resistance genes were found. Except for tet(W), a significant correlation between the positivity of resistance genes and a dysbiotic vaginal status (i.e., bacterial vaginosis (BV)) was noticed. Indeed, samples positive for at least one resistance determinant were characterized by a decrease in Lactobacillus spp. and an increase of BV-related genera (Prevotella, Gardnerella, Atopobium, Sneathia). A high predominance of vaginal Lactobacillus spp. (>85%) was associated with a lower risk of tet(W) gene detection, whereas the presence of Megasphaera (>1%) increased the risk of positivity for all analyzed genes. Different types of vaginal microbiota are associated with peculiar resistance profiles, being a lactobacilli-dominated ecosystem poor in or free of resistance genes. These data could open new perspectives for promoting maternal and neonatal health.

The inhabitants of the vaginal ecosystem can harbor genetic determinants conferring antimicrobial resistance. However, detailed data about the distribution of resistance genes in the vaginal microbiome of pregnant women are still lacking. Therefore, we assessed the presence of macrolide (i.e., erm genes) and tetracycline (i.e., tet genes) resistance markers in the vaginal environment of Caucasian women at different gestational ages. Furthermore, the detection of resistance genes was related to the composition of the vaginal microbiota. A total of 228 vaginal samples, collected at different trimesters of pregnancy or during the puerperium, were tested for the presence of ermB, ermF, tet(W), and tet(M) by in-house end-point PCR assays. The composition of the vaginal microbiota was assessed through a microscopic evaluation (i.e., Nugent score) and by means of sequencing V3–V4 hypervariable regions of the bacterial 16 rRNA gene. Overall, the most detected resistance gene was tet(M) (76.7%), followed by ermB (55.2%). In 17% of women, mainly with a ‘normal’ vaginal microbiota, no resistance genes were found. Except for tet(W), a significant correlation between the positivity of resistance genes and a dysbiotic vaginal status (i.e., bacterial vaginosis (BV)) was noticed. Indeed, samples positive for at least one resistance determinant were characterized by a decrease in Lactobacillus spp. and an increase of BV-related genera (Prevotella, Gardnerella, Atopobium, Sneathia). A high predominance of vaginal Lactobacillus spp. (>85%) was associated with a lower risk of tet(W) gene detection, whereas the presence of Megasphaera (>1%) increased the risk of positivity for all analyzed genes. Different types of vaginal microbiota are associated with peculiar resistance profiles, being a lactobacilli-dominated ecosystem poor in or free of resistance genes. These data could open new perspectives for promoting maternal and neonatal health.