Horizontal and Vertical Transfer of Oral Microbial Dysbiosis and Periodontal Disease.

One of the hallmark features of destructive periodontal disease, well documented over the last 50 y, is a change to the quantitative and qualitative composition of the associated microbiology. These alterations are now generally viewed as transformational shifts of the microbial populations associated with health leading to the emergence of bacterial species, which are only present in low abundance in health and a proportionate decrease in the abundance of others. The role of this dysbiosis of the health associated microbiota in the development of disease remains controversial: is this altered microbiology the driving agent of disease or merely a consequence of the altered environmental conditions that invariably accompany destructive disease? In this work, we aimed to address this controversy through controlled transmission experiments in the mouse in which a dysbiotic oral microbiome was transferred either horizontally or vertically into healthy recipient mice. The results of these murine studies demonstrate conclusively that natural transfer of the dysbiotic oral microbiome from a periodontally diseased individual into a healthy individual will lead to establishment of the dysbiotic community in the recipient and concomitant transmission of the disease phenotype. The inherent resilience of the dysbiotic microbial community structure in diseased animals was further demonstrated by analysis of the effects of antibiotic therapy on periodontally diseased mice. Although antibiotic treatment led to a reversal of dysbiosis of the oral microbiome, in terms of both microbial load and community structure, dysbiosis of the microbiome was reestablished following cessation of therapy. Collectively, these data suggest that an oral dysbiotic microbial community structure is stable to transfer and can act in a similar manner to a conventional transmissible infectious disease agent with concomitant effects on pathology. These findings have implications to our understanding of the role of microbial dysbiosis in the development and progression of human periodontal disease.

Sequencing of Porphyromonas gingivalis from saliva in patients with periodontitis and type 2 diabetes mellitus.

Background: Porphyromonas gingivalis is a major periodontal pathogen. Saliva is the most easy, non-invasive microbiological sample for detection of periodontal pathogens. Aim and Objectives: A prospective study on 37 diabetic patients was grouped into well-controlled diabetes with/without periodontitis and uncontrolled diabetic with periodontitis. PCR and sequencing of P. gingivalis was performed in saliva samples. Materials and Methods: DNA was extracted from saliva using Triton X-100 and 16s rRNA gene (404 bp) was amplified by polymerase chain reaction. DNA sequencing was performed for two samples. Results: P. gingivalis was detected in 27.03% (n = 10), of which 30% (n = 9) were diabetic with periodontal disease and 14.3% (n = 1) were diabetic without periodontal disease. The percentage of poor oral hygiene was 50% and 20% in uncontrolled and controlled glycaemic patients, respectively. DNA sequencing of two samples showed 100% identity with the sequences in the GenBank database (Gen Bank accession no: KX640913-KX640914). Conclusion: Type 2 diabetes mellitus and periodontitis are interlinked. Early detection of P. gingivalis and appropriate treatment with doxycycline will also assist in controlling the glycaemic status.

Estimation of Transmission of Porphyromonas Gingivalis from Mother to Child through Saliva.

INTRODUCTION: Chronic periodontitis is an infectious disease. Porphyromonas gingivalis is the major pathogen associated with it and can be found in all ecosystems in the oral cavity. The presence of this organism is highly correlated with preterm and low birth weight babies. So, this study aimed to assess vertical transmission of P.gingivalis from pregnant women to their new born. METHODS: Forty six pregnant women with chronic periodontitis were recruited for this cross-sectional study. Whole unstimulated saliva was collected from them before delivery and from their new-borns within forty eight hours of birth. Quantification of P.gingivalis in the saliva samples was carried out by quantitative real time polymerase chain reaction. The obtained data were analysed by SPSS 16 program. RESULTS: The results showed a significant correlation (P=0.002) between the number of P.gingivalis present in the mother's saliva with that of the new-borns' saliva. DNA copies of more than 5000/µl of P.gingivalis was found in 20 (43.5%) maternal saliva and 21 (45.7%) in new-borns' saliva. Both Plaque index and Extent and Severity index showed no correlation (P>0.05) with DNA copies of P.gingivalis in new-borns' saliva. CONCLUSIONS: The DNA copies of P.gingivalis found in new-borns' saliva are in par with mother saliva, as the saliva sample obtained from new-borns' were within forty eight hours of birth, no other environmental factor can have a direct role in its transmission. Thus, it can be concluded that P.gingivalis is vertically transmitted from mother to child.

Inguinal syndrome secondary to Prevotella bivia after accidental bite in orogenital sex.

The authors report a case of an inguinal bubo in a young man caused by an anaerobe, Prevotella bivia, which was acquired during oral sexual intercourse. As far as the authors know, this is the first reported case of a sexually transmitted infection by Prevotella. Prevotella spp. inhabit the oral cavity and are highly prevalent in bacterial vaginosis, a polymicrobial syndrome resulting from replacement of the normal vaginal Lactobacillus spp. flora by high concentrations of anaerobic microorganisms such as Prevotella spp., Mobiluncus spp., Gardnerella vaginalis and other uncultivated anaerobes.

Colonization of maternal and fetal tissues by Porphyromonas gingivalis is strain-dependent in a rodent animal model.

OBJECTIVE: The objective of this study was to develop a rodent model of Porphyromonas gingivalis infection during pregnancy. STUDY DESIGN: Sprague Dawley rats were infected intravenously with 10(5), 10(7), or 10(9) CFU per dam of P gingivalis strain W83, ATCC 33277, or A7436 at gestational day 14 and necropsied at gestational day 18. Maternal organs were cultured to assess the spread of the infection. Six fetal units (placenta, amniotic fluid, membranes, and fetus) per dam were cultured; additional fetal units were examined by histopathology. Polymerase chain reaction was performed on placentas. RESULTS: Colonization rates were dependent on the strain of P gingivalis used and the infection dose. At an infection dose of 10(9) CFU/dam, P gingivalis W83, ATCC 33277, or A7436 was detected in 33%, 83%, or 100% of placentas, respectively. Epithelial hyperplasia, cellular necrosis, and inflammatory infiltrate were observed in infected placental tissues. CONCLUSION: This study demonstrated that P gingivalis can invade both maternal and fetal tissues, resulting in chorioamnionitis and placentitis.

Java project on periodontal diseases: a study on transmission of Porphyromonas gingivalis in a remote Indonesian population.

AIM: To study transmission of Porphyromonas gingivalis in a population living in a remote area in Southern Java, Indonesia. MATERIAL AND METHODS: Subgingival plaque samples from 167 subjects with varying degrees of periodontal breakdown were obtained and cultured for the presence of P. gingivalis. After extraction and purification of bacterial DNA, amplified fragment length polymorphism technique was applied to genotype the bacterial isolates. Computer-assisted analysis of the bacterial DNA profiles was used to study distribution of P. gingivalis genotypes within family units. RESULTS: One hundred and five of the 167 (63%) subjects were culture positive for P. gingivalis. In total, 371 P. gingivalis isolates were obtained from the 105 subjects. Of the 105 subjects, 30 were siblings representing 13 families. In six of the 13 families (46%), identical P. gingivalis genotypes were found among siblings. In the study group of 105 subjects, 13 married couples were identified of which both spouses were culture positive for P. gingivalis. None of the 13 couples shared an identical P. gingivalis genotype. Twenty P. gingivalis-positive subjects had spouses that were culture negative for P. gingivalis. CONCLUSIONS: In this study population, vertical transmission of P. gingivalis has occurred within family units, most likely from parents to children. Transmission of P. gingivalis between spouses could not be established.

Intercellular spreading of Porphyromonas gingivalis infection in primary gingival epithelial cells.

Porphyromonas gingivalis, an important periodontal pathogen, is an effective colonizer of oral tissues. The organism successfully invades, multiplies in, and survives for extended periods in primary gingival epithelial cells (GECs). It is unknown whether P. gingivalis resides in the cytoplasm of infected cells throughout the infection or can spread to adjacent cells over time. We developed a technique based on flow cytofluorometry and fluorescence microscopy to study propagation of the organism at different stages of infection of GECs. Results showed that P. gingivalis spreads cell to cell and that the amount of spreading increases gradually over time. There was a very low level of propagation of bacteria to uninfected cells early in the infection (3 h postinfection), but there were 20-fold and 45-fold increases in the propagation rate after 24 h and 48 h, respectively, of infection. Immunofluorescence microscopy of infected cells suggested that intercellular translocation of P. gingivalis may be mediated through actin-based membrane protrusions, bypassing the need for release of bacteria into extracellular medium. Consistent with these observations, cytochalasin D treatment of infected cells resulted in significant inhibition of bacterial spreading. This study shows for the first time that P. gingivalis disseminates from cell to cell without passing through the extracellular space. This mechanism of spreading may allow P. gingivalis to colonize oral tissues without exposure to the humoral immune response.

Transmission of periodontal bacteria and models of infection.

BACKGROUND: Bacteria play an essential role in the aetiology of periodontitis. Most bacterial species isolated from subgingival plaque are indigenous to the oral cavity. Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis are detected infrequently in periodontal health, which makes these species prime candidates to study person-to-person transmission. The aim of the present study was to review the literature on transmission of these periodontal bacterial species. METHOD: We review the literature on bacterial typing techniques and summarize the information on clonal distribution of A. actinomycetemcomitans and P. gingivalis in family units based on different typing techniques in order to establish the likelihood for person-to-person transmission of these periodontal pathogens. RESULTS: Vertical transmission of A. actinomycetemcomitans is estimated to be between 30% and 60%, whereas vertical transmission of P. gingivalis has rarely been observed. Horizontal transmission between spouses ranges between 14% and 60% for A. actinomycetemcomitans and between 30% and 75% for P. gingivalis. There is some evidence to show that cohabitation with a periodontitis patient influences the periodontal status of the spouse; however, substantially more information is needed to prove this hypothesis. CONCLUSIONS: Transmission of putative periodontal pathogens between family members has been shown. The clinical consequences of these events have been poorly documented. Based on the current knowledge, screening for and prevention of transmission of specific virulent clones of A. actinomycetemcomitans may be feasible and effective in preventing some forms of periodontal disease. P. gingivalis is usually recovered from diseased adult subjects, and transmission of this pathogens seems largely restricted to adult individuals. Horizontal transmission of P. gingivalis may therefore be controlled by periodontal treatment involving elimination or significant suppression of the pathogen in diseased individuals and by a high standard of oral hygiene.

Human granulocytic anaplasmosis affecting the myocardium.

A case of 65-year-old male is reported who presented with myalgias, headache, and fever. He subsequently developed myocarditis and was diagnosed to have anaplasmosis on peripheral blood smear. He was treated with doxycycline for 30 days. A coronary angiogram done after recovery showed normal epicardial arteries. The case illustrates the importance of a careful examination of the peripheral smear, with a high index of clinical suspicion, which led to prompt treatment and complete recovery of the patient.

Chronic maternal and fetal Porphyromonas gingivalis exposure during pregnancy in rabbits.

OBJECTIVE: This study was undertaken to develop a rabbit model of maternal exposure to Porphyromonas gingivalis and determine whether fetal or placental exposure occurs. STUDY DESIGN: Subcutaneous steel chambers were implanted in 8 New Zealand White female rabbits. On day 7 of pregnancy, 4 rabbits were inoculated through the chamber with 5 x 10 8 CFU/mL live P gingivalis , and 4 rabbits with broth (controls) and sacrificed at term. Polymerase chain reaction was used to detect P gingivalis in maternal and fetal liver and placenta. Fisher exact test was used to compare P gingivalis detection between groups. RESULTS: Among exposed does, P gingivalis was detected in 33% of the maternal livers, 49% of placentas, and 34% fetal livers compared with none from controls ( P < .001). CONCLUSION: Chronic maternal exposure to P gingivalis results in systemic dissemination, transplacental passage, and fetal exposure. This model may be useful to study placental and fetal effects of this oral pathogen and to study microbial dissemination across the placenta.