Multi-cohort shotgun metagenomic analysis of oral and gut microbiota overlap in healthy adults.

The multitude of barriers between the mouth and colon may eliminate swallowed oral bacteria. Ascertaining the presence of the same bacteria in the mouth and colon is methodologically challenging partly because 16S rRNA gene sequencing - the most commonly used method to characterize the human microbiota - has low confidence in taxonomic assignments deeper than genus for most bacteria. As different species of the same genus can have low-level variation across the same 16S rRNA gene region, shotgun sequencing is needed to identify a true overlap. We analyzed a curated, multi-cohort, shotgun metagenomic database with species-level taxonomy and clade-specific marker genes to fill this knowledge gap. Using 500 paired fecal/oral (4 oral sites) samples from 4 healthy adult cohorts, we found a minute overlap between the two niches. Comparing marker genes between paired oral and fecal samples with species-level overlap, the pattern of overlap in only 7 individuals was consistent with same-strain colonization. These findings argue against ectopic colonization of oral bacteria in the distal gut in healthy adults.

MASCC/ISOO expert opinion on the management of oral problems in patients with advanced cancer.

PURPOSE: The Palliative Care Study Group in conjunction with the Oral Care Study Group of the Multinational Association for Supportive Care in Cancer (MASCC) formed a sub-group to develop evidence-based guidance on the management of common oral problems in patients with advanced cancer. METHODS: This guidance was developed in accordance with the MASCC Guidelines Policy. A search strategy for Medline was developed, and the Cochrane Database of Systematic Reviews and the Cochrane Central Register of Controlled Trials were explored for relevant reviews and trials, respectively. Guidance was categorised by the level of evidence, and "category of guideline" (i.e., "recommendation", "suggestion" or "no guideline possible"). RESULTS: Twelve generic suggestions (level of evidence - 5), three problem-specific recommendations and 14 problem-specific suggestions were generated. The generic suggestions relate to oral hygiene measures, assessment of problems, principles of management, re-assessment of problems and the role of dental/oral medicine professionals. CONCLUSIONS: This guidance provides a framework for the management of common oral problems in patients with advanced cancer, although every patient requires individualised management.

A Review of Oral Chronic Graft-Versus-Host Disease: Considerations for dental hygiene practice.

Purpose: Allogeneic hematopoietic cell transplantation (alloHCT), also known as stem cell or bone marrow transplantation, is a cellular therapy performed to treat a variety of malignant and non-malignant hematologic diseases. Chronic graft-versus-host disease (cGVHD) is a common immune-mediated complication of alloHCT that can affect various organs of the body, with approximately 70% of affected patients presenting with oral features. Oral manifestations of cGVHD include lichenoid lesions (diagnostic feature), erythema, pseudomembranous ulcerations, superficial mucoceles, salivary gland hypofunction, xerostomia, orofacial sclerosis, trismus, and increased sensitivity to spicy, acidic, hard, and crunchy foods. Patients with oral cGVHD are also at increased risk for developing secondary conditions, such as oral candidiasis, dental caries, and oral squamous cell carcinoma. Given these complex oral health challenges, the dental hygienist can play a key role in optimizing patients' oral health care from pre-stem cell transplantation through survivorship. Optimal care includes a comprehensive health history assessment, thorough extraoral and intraoral examinations, detailed hard and soft tissue evaluations, oral hygiene, and dietary assessment, along with the delivery of patient-centered, oral health instruction and preventive therapies. Appropriate monitoring and management of oral cGVHD require a collaborative care approach between dental, oncology, and oral medicine providers. As part of a multidisciplinary care team, dental hygienists play an important role in the management of patients with oral cGVHD. The purpose of this review is to provide an overview of alloHCT and its oral health considerations, with a focus on oral cGVHD etiology, signs and symptoms, and management considerations for the dental team.

Bone Health Management After Hematopoietic Cell Transplantation: An Expert Panel Opinion from the American Society for Transplantation and Cellular Therapy.

Bone health disturbances commonly occur after hematopoietic cell transplantation (HCT) with loss of bone mineral density (BMD) and avascular necrosis (AVN) foremost among them. BMD loss is related to pretransplantation chemotherapy and radiation exposure and immunosuppressive therapy for graft-versus-host-disease (GVHD) and results from deficiencies in growth or gonadal hormones, disturbances in calcium and vitamin D homeostasis, as well as osteoblast and osteoclast dysfunction. Although the pathophysiology of AVN remains unclear, high-dose glucocorticoid exposure is the most frequent association. Various societal treatment guidelines for osteoporosis exist, but the focus is mainly on menopausal-associated osteoporosis. HCT survivors comprise a distinct population with unique comorbidities, making general approaches to bone health management inappropriate in some cases. To address a core set of 16 frequently asked questions (FAQs) relevant to bone health in HCT, the American Society of Transplant and Cellular Therapy Committee on Practice Guidelines convened a panel of experts in HCT, adult and pediatric endocrinology, orthopedics, and oral medicine. Owing to a lack of relevant prospective controlled clinical trials that specifically address bone health in HCT, the answers to the FAQs rely on evidence derived from retrospective HCT studies, results extrapolated from prospective studies in non-HCT settings, relevant societal guidelines, and expert panel opinion. Given the heterogenous comorbidities and needs of individual HCT recipients, answers to FAQs in this article should be considered general recommendations, with good medical practice and judgment ultimately dictating care of individual patients. Readers are referred to the Supplementary Material for answers to additional FAQs that did not make the core set.

World Workshop on Oral Medicine VII: Relative frequency of oral mucosal lesions in children, a scoping review.

OBJECTIVE: To detail a scoping review on the global and regional relative frequencies of oral mucosal disorders in the children based on both clinical studies and those reported from biopsy records. MATERIALS AND METHODS: A literature search was completed from 1 January 1990 to 31 December 2018 using PubMed and EMBASE. RESULTS: Twenty clinical studies (sample size: 85,976) and 34 studies from biopsy services (40,522 biopsies) were included. Clinically, the most frequent conditions were aphthous ulcerations (1.82%), trauma-associated lesions (1.33%) and herpes simplex virus (HSV)-associated lesions (1.33%). Overall, the most commonly biopsied lesions were mucoceles (17.12%), fibrous lesions (9.06%) and pyogenic granuloma (4.87%). By WHO geographic region, the pooled relative frequencies of the most common oral lesions were similar between regions in both clinical and biopsy studies. Across regions, geographic tongue (migratory glossitis), HSV lesions, fissured tongue and trauma-associated ulcers were the most commonly reported paediatric oral mucosal lesions in clinical studies, while mucoceles, fibrous lesions and pyogenic granuloma were the most commonly biopsied lesions. CONCLUSIONS: The scoping review suggests data from the clinical studies and biopsy records shared similarities in the most commonly observed mucosal lesions in children across regions. In addition, the majority of lesions were benign in nature.