Porphyromonas gingivalis and the pathogenesis of Alzheimer's disease

The cause of Alzheimer's disease (AD), and the pathophysiological mechanisms involved, remain major unanswered questions in medical science. Oral bacteria, especially those species associated with chronic periodontitis and particularly Porphyromonas gingivalis, are being linked causally to AD pathophysiology in a subpopulation of susceptible individuals. P. gingivalis produces large amounts of proteolytic enzymes, haem and iron capture proteins, adhesins and internalins that are secreted and attached to the cell surface and concentrated onto outer membrane vesicles (OMVs). These enzymes and adhesive proteins have been shown to cause host tissue damage and stimulate inflammatory responses. The ecological and pathophysiological roles of P. gingivalis OMVs, their ability to disperse widely throughout the host and deliver functional proteins lead to the proposal that they may be the link between a P. gingivalis focal infection in the subgingivae during periodontitis and neurodegeneration in AD. P. gingivalis OMVs can cross the blood brain barrier and may accelerate AD-specific neuropathology by increasing neuroinflammation, plaque/tangle formation and dysregulation of iron homeostasis, thereby inducing ferroptosis leading to neuronal death and neurodegeneration.

Update on Focal Infection Management: A Czech Interdisciplinary Consensus

BACKGROUND

The focal infection theory has been used to explain several chronic systemic diseases in the past. Systemic diseases were thought to be caused by focal infections, such as caries and periodontal diseases, and dentists were held responsible for these diseases due to the spread of oral infections. As knowledge of the interrelationship between oral microorganisms and the host immune response has evolved over the last few decades, the focal infection theory has been modified in various ways. The relationship between oral and systemic health appears to be more complex than that suggested by the classical theory of focal infections. Indeed, the contribution of the oral microbiota to some systemic diseases is gaining acceptance, as there are strong associations between periodontal disease and atherosclerotic vascular disease, diabetes, and hospital-associated pneumonia, amongst others. As many jurisdictions have various protocols for managing this oral-systemic axis of disease, we sought to provide a consensus on this notion with the help of a multidisciplinary team from the Czech Republic.

METHODS

A multidisciplinary team comprising physicians/surgeons in the specialities of dentistry, ear-nose and throat (ENT), cardiology, orthopaedics, oncology, and diabetology were quetioned with regard to their conceptual understanding of the focal infection theory particularly in relation to the oral-systemic axis. The team also established a protocol to determine the strength of these associations and to plan the therapeutic steps needed to treat focal odontogenic infections whenever possible.

RESULTS

Scoring algorithms were devised for odontogenic inflammatory diseases and systemic risks, and standardised procedures were developed for general use.

CONCLUSIONS

The designed algorithm of the oral-systemic axis will be helpful for all health care workers in guiding their patient management protocol.

Final-year medical students' perspective: a survey on the use of computed tomography in sepsis

OBJECTIVES

To determine the perspective of final-year medical students on the use of computed tomography (CT) in patients with sepsis.

METHODS

A total of 207 questionnaires were distributed to final-year medical students at a large university medical center, and 113 returned questionnaires met the criteria for inclusion in the analysis. Questions referred to sepsis guidelines, CT indications, and the use of contrast agents. Control variables included a level of practical experience as a final-year student (trimester of student's practical year) and previous radiological experience. Statistical hypothesis tests such as the Mann-Whitney U test and chi-square test were performed.

RESULTS

The majority of participating students, 85% (n = 91/107), considered a Systemic Organ Failure Assessment (SOFA) score ≥ 2 as a diagnostic criterion for sepsis. The presence of ≥ 2 positive systemic inflammatory response syndrome (SIRS) criteria was considered relevant for diagnosing sepsis by 34% (n = 34/100). Ninety-nine percent (n = 64/65) of the participants who fully agreed with a SOFA score ≥ 2 being relevant for diagnosing sepsis would also use it as an indication for a CT scan. Seventy-six percent (n = 78/103) of the students rated a known severe allergic reaction to contrast agents as an absolute contraindication for its administration. Ninety-five percent (n = 78/82) considered radiation exposure as problematic in CT examinations, especially in repeat CTs.

CONCLUSION

Most final-year medical students were familiar with the sepsis criteria. Still, some referred to outdated diagnostic criteria. Participants saw the ability to plan further patient management based on CT as a major benefit. Most participants were aware of radiation as a risk of CT.

CRITICAL RELEVANCE STATEMENT

More detailed knowledge of CT in septic patients should be implemented in the medical curriculum. Retraining of medical students could help increase student confidence potentially improving patient care.

KEY POINTS

1. Whereas the majority of final-year medical students were familiar with sepsis criteria, some referred to outdated diagnostic criteria. 2. Participants saw the ability to plan further patient management based on CT as a major benefit. 3. Most participants were aware of radiation as a risk of CT.

The oral microbial composition and diversity affect the clinical course of palmoplantar pustulosis patients after dental focal infection treatment

BACKGROUND

Palmoplantar pustulosis (PPP) is a chronic pustular dermatosis on the palms and soles. Dental focal infections are known as the major worsening factor for PPP. Recent our study of oral microbiome demonstrated dysbiosis in PPP patients. While almost half of the PPP patients improved after treatment of dental focal infections, a certain number of patients did not improve.

OBJECTIVE

To investigate the oral microbial factors affecting the clinical course of PPP after treatment of dental focal infection.

METHODS

The oral microbiota of healthy controls (n = 10), improved (n = 7) and not-improved (n = 6) patients were analyzed by sequencing of bacterial 16S ribosomal RNA gene.

RESULTS

The UniFrac analysis suggested the differences of oral microbiota between improved and not-improved patients. The prevalence of the phylum Proteobacteria was lower in improved patients than in not-improved patients. When the alpha microbial diversity was assessed by Shannon index, Pielou's index and the average operational taxonomic units (OTUs), not-improved patients had a lower-diversity microbiota compared to improved patients. The degree of changes of oral microbiota after dental focal infection treatment was higher in improved patients than in not-improved patients. Six genera showed significant correlation with blood test data of PPP patients.

CONCLUSION

Our findings suggested that oral microbial compositions and diversity could account for the distinct clinical course of PPP patients after treatment of dental focal infection. Oral microbiome analysis of PPP patients may provide a predictive factor for clinical responsiveness to dental focal infection treatment.

Assessment of oral health condition in recipients of allogeneic hematopoietic cell transplantation

Introduction

The optimization of oral health before allogeneic hematopoietic cell transplantation (HCT) is important for preventing infectious complications during treatment.

Objective

The objective of this study was to evaluate the oral health condition and dental treatments performed in patients in pre-allogeneic HCT.

Method

The records of patients treated during 2018 at a Brazilian HCT service were reviewed.

The following oral health data were obtained: 1. Decayed, missing and filled teeth / correlated index for primary dentition (DMFT/dmft); 2. Quality of oral hygiene and 3. Dental pathologies: 3.1 Periodontal infectious focus, 3.2 Endodontic infectious focus and 3.3 Carie incidence. All dental procedures performed were surveyed.

Results

Thirty-three patients were included, with a mean age of 28.42 (±16.37), 20 male (60%) and 13 female. The average DMFT/dmft found in this study was 10.24 (± 8.37), similar to the index found in the population in southeastern Brazil. The younger study population presented a DMFT/dmft considered high, when compared to the general population. A total of 27.2% of the patients had active caries lesions, 33.3%, foci of periodontal infection, 15.1%, endodontic infectious focus and 40%, poor oral hygiene. Almost half of the patients (48.4%) had to undergo dental intervention, 24.2% needing periodontal scaling, 21.2%, fillings and 12.1%, tooth extractions.

Conclusion

We conclude that the studied population had an important incidence of dental pathologies and infectious conditions that could complicate throughout HCT, especially in younger patients, therefore presenting a high demand for dental treatment in the pre-HCT. Studies that assess the impact of dental conditioning on the outcomes of HCT with an emphasis on dental infectious complications, days of hospitalization and survival are necessary.”

The role of body computed tomography in hospitalized patients with obscure infection: Retrospective consecutive cohort study

OBJECTIVE

Patients with severe infection or sepsis require fast identification of the focus and prompt eradication. This study aims at investigating the role of body computed tomography (CT) and identifying outcome predictors in a general ward setting of patients with obscure infection.

METHODS

We retrospectively identified 196 consecutive body CTs acquired in 179 patients with obscure infection, i.e. severe infection or sepsis from general wards with unclear focus, over 12-months in the year 2018. Reports were extracted using a full-text search in the radiological information system (RIS) of a large university medical center. CT reports were classified according to diagnostic confidence of the reader (i.e. certain, likely, possible, no focus), and correlated with clinical and laboratory parameters. The discharge diagnosis was set as the diagnostic reference standard. Contingency tables were prepared for statistical analysis with Chi-squared test amongst other analyses and the calculation of AUC statistics.

RESULTS

In 133 out of 196 (67.9 %) body CTs from general wards with severe infection or sepsis, body CT identified an infectious focus. 90 % of the infections were located in the chest, abdomen, and genitourinary tract, in descending order. In 76.5 % (150 of 196) of examinations, CT correctly predicted the final infectious source. The positive predictive value (PPV) of a CT-detected focus was 84.2 % (95 % CI 79.0%-88.3%). A high diagnostic confidence of the reader resulted in a PPV of 96.4 % (95 % CI 87.4%-99.1%) while a low confidence resulted in a PPV of 63.3 % (95 % CI 48.2%-76.3%).

CONCLUSION

In patients with obscure infection treated in general wards, body CT detects the infectious source with a high positive predictive value. Focus detection accuracy highly depends on the diagnostic confidence of the CT reader.

The burden and costs of sepsis and reimbursement of its treatment in a developing country: An observational study on focal infections in Indonesia

OBJECTIVES

This study aimed to determine the burden of sepsis with focal infections in the resource-limited context of Indonesia and to propose national prices for sepsis reimbursement.

METHODS

A retrospective observational study was conducted from 2013-2016 on cost of surviving and non-surviving sepsis patients from a payer perspective using inpatient billing records in four hospitals. The national burden of sepsis was calculated and proposed national prices for reimbursement were developed.

RESULTS

Of the 14,076 sepsis patients, 5,876 (41.7%) survived and 8,200 (58.3%) died. The mean hospital costs incurred per surviving and deceased sepsis patient were US$1,011 (SE ± 23.4) and US$1,406 (SE ± 27.8), respectively. The national burden of sepsis in 100,000 patients was estimated to be US$130 million. Sepsis patients with multifocal infections and a single focal lower-respiratory tract infection (LRTI) were estimated as being the two with the highest economic burden (US$48 million and US$33 million, respectively, within 100,000 sepsis patients). Sepsis with cardiovascular infection was estimated to warrant the highest proposed national price for reimbursement (US$4,256).

CONCLUSIONS

Multifocal infections and LRTIs are the major focal infections with the highest burden of sepsis. This study showed varying cost estimates for sepsis, necessitating a new reimbursement system with adjustment of the national prices taking the particular foci into account.

Incremental value of metagenomic next generation sequencing for the diagnosis of suspected focal infection in adults

OBJECTIVES

Microbiological diagnosis is essential during clinical management of focal infections. Metagenomic next generation sequencing (mNGS) has been reported as a promising diagnostic tool in infectious diseases. However, little is known about the clinical utility of mNGS in focal infections.

METHODS

We conducted a single-center retrospective study to investigate impact of mNGS on focal infection diagnosis and compared it with conventional methods, including culture, pathological examination, Xpert MTB/RIF, etc. 98 suspected focal infections cases were enrolled, and medical records were reviewed to determine their rates of detection, time-to-identification, and clinical outcomes.

RESULTS

mNGS showed a satisfying diagnostic positive percent agreement of 86.30% (95% CI: 75.79-92.88%) in a variety of tissues, compared to 45.21% (95% CI: 33.68-57.24%) for culture and 57.53% (95% CI: 45.43-68.84%)f for conventional methods (p < 0.0125), and detected an extra 34 pathogenic microorganisms. Time requirement for pathogen identification using mNGS ranges from 31 h to 55 h, which showed an advantage over culture. (82.36 h; 95%CI: 65.83, 98.89; P < 0.05) CONCLUSIONS: mNGS showed promising potential in pathogenic diagnosis during focal infections and might enable clinicians to make more timely and targeted therapeutic decisions.

Influence of pathogen and focus of infection on procalcitonin values in sepsis patients with bacteremia or candidemia

Background

This study aimed to evaluate the accuracy of procalcitonin (PCT) serum concentrations to diagnose Gram-negative bacteremia and the association of PCT serum concentrations with more specific pathogens and the focus of infection.

Methods

Secondary analysis of the prospectively collected patient-level dataset from a cluster randomized quality improvement trial was performed. The trial included sepsis patients with organ dysfunction treated in the participating intensive care units from 2011 to 2015. Test performance for the prediction of Gram-negative bacteremia was assessed by receiver operating curve analysis. Independent effects of specific pathogen groups and foci of infection on PCT concentrations were assessed by linear logistic regression models.

Results

Blood cultures (BC) and PCT concentrations had been taken in 4858 of 6561 documented patients. PCT was significantly higher in Gram-negative bacteremia compared to Gram-positive bacteremia or candidemia (p < 0.001). The area under the curve was 0.72 (95% confidence interval 0.71–0.74) for the prediction of Gram-negative bacteremia compared to all other blood culture results including negative blood cultures. The optimized cutoff value was 10 ng/ml (sensitivity 69%, specificity 35%). PCT differed significantly between specific groups of pathogens (p < 0.001) with highest concentrations in Escherichia coli, Streptococcus species and other Enterobacteriaceae. PCT was highest in urogenital followed by abdominal infection and lowest in respiratory infection (p < 0.001). In a linear regression model, Streptococci, E. coli and other Enterobacteriaceae detected from BC were associated with three times higher PCT values. Urogenital or abdominal foci of infection were associated with twofold increased PCT values independent of the pathogen.

Conclusions

Serum PCT concentrations are higher in patients with Gram-negative bacteremia than in patients with Gram-positive bacteremia or candidemia. However, the discriminatory power of this difference is too low to guide therapeutic decisions. Variations in PCT serum concentrations are not determined solely by Gram-negative or Gram-positive bacteria but are also affected by distinct groups of pathogens and different foci of infection.

Trial registration

ClinicalTrials.gov, NCT01187134. Registered on 23 August 2010.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-2050-9) contains supplementary material, which is available to authorized users.

Breast Abscess by Salmonella Paratyphi A: Case Report and Literature Review

A case of suspicious breast mass due to Salmonella enterica serotype Paratyphi A in a non-lactating, diabetic female is being described. The infection was successfully treated with a combination of surgical drainage and antibiotic treatment. This case highlights the fact that a focal Salmonella infection involving the breast should be considered as a rare differential diagnosis for breast malignancy and submission of specimens for microbiological analysis may be helpful in establishment of an accurate diagnosis and management.

Diagnosis and conservative treatment of extraoral submental sinus tract of endodontic origin: a case report

Sinus tracts (or fistulas) are a common manifestation of pulpal necrosis that requires conventional -or rarely surgical- endodontic treatment in order to heal. They are mainly identified intraorally and in rare cases they manifestate extraorally, depending on the causative tooth, root location, bone thickness and muscle inserts. Such conditions may be misdiagnosed and confused with other non-pulpal pathologies. A case of extra-oral submental sinus tract that was initially misdiagnosed by a physician as a non-odontogenic lesion is presented. Facial fistulas of endodontic origin, despite sparse, should be considered as an option in the differential diagnosis procedure. It is important that interaction occurs between physicians and dentists to avoid exposing patients to insufficient treatment schemes.

Oral microbiota and systemic disease

It is well known that bacteria are the primary cause of infectious diseases, however, evidence is emerging that these organisms are also indirectly responsible for several diseases including cancer and rheumatoid arthritis. The oral cavity is home to several million bacteria that can cause two major diseases-periodontitis and caries. The relationship between periodontopathic bacteria and systemic diseases has been explored for several years. The concept of the oral cavity as a source of distant infection has been debated for at least a century. This review will discuss the historic aspects of the development of the focal infection theory, the reasons for its demise, its re-emergence and current status.

Cutaneous small vessel vasculitis accompanied by pustulosis palmaris et plantaris

We present the case of a 64-year-old woman who has suffered from pustulosis palmaris et plantaris for 10 years. At the first examination, many erythematous lesions with purpura, blood crusts, and blisters were present in the lower legs and dorsum of the feet. Painful swelling in the sternal region and dorsal pain were also noted. Elevation of the CRP and myogenic enzyme levels, and liver and renal dysfunctions were noted on blood testing. Histopathologically, leukocytoclastic vasculitis was noted in small blood vessels in the whole dermal layers, and deposition of IgM and C3 in the vascular wall was detected by the direct immunofluorescence techniques. Based on these findings, cutaneous small vessel vasculitis was diagnosed. Because the patient complained of a toothache during the clinical course, an X-ray examination was performed. On pantomography, a radicular cyst and apical periodontitis were noted. The tooth symptoms changed with exacerbation and remission of the skin symptoms. These findings indicate that odontogenic infection is very likely to be a cause of cutaneous small vessel vasculitis in a manner similar to pustulosis palmaris et plantaris.