Parvimonas micra: A rare cause of native joint septic arthritis

Fog caused distinct diversity of airborne bacterial communities enriched with pathogens over central Indo-Gangetic plain in India

Fog causes enhancement of bacterial loading in the atmosphere. Current study represents the impact of occurrences of fog on the alteration of diversity of airborne bacteria and their network computed from metagenomic data of airborne samples collected at Arthauli (25.95°N, 85.10°E) situated at central Indo-Gangetic Plain (IGP) during 1-14 January 2021. A distinct bacterial diversity with a complex network is identified in foggy condition due to the enrichment of unique types of bacteria. Present investigation highlights a statistically significant enrichment of airborne pathogenic bacteria found in a unique ecosystem within air evolved due to the occurrences of fog over central IGP. In the foggy network, Cutibacterium, an opportunistic pathogen, is identified to be interacting maximum (21 edges) with other bacteria with statistically significant copresence relation, which are responsible for various infections for human beings. A 40-60% increase (p < 0.01) in the abundance of pathogenic bacteria for respiratory and skin diseases is noticed in fog period. Among the fog-enriched bacteria, Cutibacterium, Herbaspirillum, Paenibacillus, and Tsukamurella are examples of opportunistic bacteria causing various respiratory diseases, while Paenibacillus can even cause skin cancer and acute lymphoblastic leukemia.

Severe pneumonia with empyema caused by Parvimonas micra and Streptococcus constellatus co-infection: a case report

Empyema is a common complication of pneumonia, caused by the accumulation of purulent exudate due to pathogenic bacteria invading the pleural cavity. Parvimonas micra and Streptococcus constellatus are pathogens that rarely cause pneumonia with empyema. Herein, a case of severe empyema caused by these two pathogens, confirmed by metagenomic next-generation sequencing (mNGS) of pleural effusion cultures, is reported. A male Chinese patient in his late sixties presented with wheezing, cough, sputum expectoration, and fever. Blood and sputum cultures were negative for pathogens, but the pleural effusion culture was positive for S. constellatus, and was also found to contain P. micra, confirmed by mNGS. The patient's symptoms improved after treatment with cefoperazone/sulbactam and moxifloxacin. Pneumonia caused by P. micra and S. constellatus is rare; however, coinfection with these pathogens may cause severe pneumonia, with or without empyema.

Case Report and Literature Review of Parvimonas micra: Difficult-to-Treat Arthritis in Hiding

Septic arthritis is a life-threatening rheumatological syndrome that is highly related to a patient's immune status and comorbidities, and although the most common clinical presentation is rapid-onset monoarthritis, it can also appear as subacute or chronic joint swelling. In these cases, differential diagnosis is more challenging, but early diagnosis and treatment is no less urgent to ensure a good global prognosis and the best outcome of the affected joint. Anaerobic microorganisms, such as Parvimonas micra, are an uncommon cause of septic arthritis (less than 5% of cases) but may be the cause of subacute arthritis. Knowledge about Parvimonas micra is important, as it is difficult to culture in the laboratory and generates a synovial fluid with atypical characteristics for septic arthritis so that, if not suspected, its diagnosis can be easily overlooked and underdiagnosed. We present the case of a 76-year-old woman with subacute arthritis of the left knee, describe the difficult diagnosis and treatment of its unexpected cause (Parvimonas micra), and review previously described cases, identifying the possible common comorbidities that may help clinicians easily find and treat this cause of subacute septic arthritis.

A rare anaerobic cause of vertebral osteomyelitis and psoas abscess: A case study

Parvimonas micra is an obligate anaerobe that forms part of the normal gastrointestinal flora. The advent of matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF) and 16s ribosomal RNA gene sequencing has led to increased detection of many rare anaerobic isolates, including Parvimonas micra. Typical risk factors for Parvimonas micra bacteremia include dental procedures or spinal instrumentation. Here, we report a case of Parvimonas micra spondylodiscitis and psoas abscess in a patient with no obvious antecedent risk factors and explore the challenges in isolation of the organism from tissue samples.

Bacteria and macrophages in the tumor microenvironment

Cancer and microbial infections are significant worldwide health challenges. Numerous studies have demonstrated that bacteria may contribute to the emergence of cancer. In this review, we assemble bacterial species discovered in various cancers to describe their variety and specificity. The relationship between bacteria and macrophages in cancer is also highlighted, and we look for ample proof to establish a biological basis for bacterial-induced macrophage polarization. Finally, we quickly go over the potential roles of metabolites, cytokines, and microRNAs in the regulation of the tumor microenvironment by bacterially activated macrophages. The complexity of bacteria and macrophages in cancer will be revealed as we gain a better understanding of their pathogenic mechanisms, which will lead to new therapeutic approaches for both inflammatory illnesses and cancer.

Classification of salivary bacteriome in asymptomatic COVID-19 cases based on long-read nanopore sequencing

The coronavirus (COVID-19) global pandemic has impacted the health of almost everyone, including changes in their salivary microbiota. Since 2019, there has been an increase in the number of new COVID-19 cases in Thailand. Therefore, COVID-19 active case finding is important for early detection and epidemic control. Moreover, the dynamic changes of salivary bacteriome in asymptomatic COVID-19 cases are largely unknown. This research aimed to investigate and compare the salivary bacteriome and the co-infectious bacterial pathogens in the asymptomatic COVID-19 positive group to the negative group, based on novel nanopore sequencing. This cohort was a cross-sectional study including saliva samples collected from 82 asymptomatic participants (39 COVID-19 positive and 43 COVID-19 negative cases). All samples were sequenced for the full-length bacterial 16S rDNA. The alpha and beta diversity analyses were not significantly different between groups. The three major species in salivary bacteriome including Veillonella parvula, Streptococcus mitis, and Prevotella melaninogenica were observed in both groups. Interestingly, Lautropia mirabilis was a significantly enriched species in the saliva of the asymptomatic COVID-19-positive cases based on linear discriminant analysis effect size (LEfSe) analysis. The results suggested that L. mirabilis was a co-infectious agent in the asymptomatic COVID-19 group. However, the potential role of L. mirabilis should be validated in further experimental studies.

Parvimonas micra Causing Emphysematous Osteomyelitis: A Case Report

CASE

We present an interesting case of femoral emphysematous osteomyelitis (EO) in a 67-year-old patient with the offending pathogen to be Parvimonas micra. Two knee arthrotomies with lateral thigh exploration were performed to debride and irrigate the bone and compartments. Although the patient initially improved, definitive treatment with an antibiotic intramedullary rod was necessary and resulted in complete resolution.

CONCLUSION

We present the first case of EO secondary to P. micra described in the literature and recommend aggressive surgical management for complete resolution and preserved functional outcome.

Primary septic arthritis of the knee caused by Neisseria meningitidis serogroup B in an elderly patient. Case report and review of the literature

PURPOSE

Primary meningococcal arthritis (PMA) represents an uncommon clinical presentation of meningococcal infection, mainly reported among young people. Herein, a case of PMA of the knee in an elderly patient is described.

CASE PRESENTATION

On January 2022, an 87-year-old patient arrived at hospital with continuous fever persisting for three days and a picture of pain, swelling, redness, and warmth of her left knee. An arthrocentesis was promptly performed and the inoculated synovial fluid turned positive with numerous Gram-negative diplococci at the microscopic examination. The identification of bacteria was done in 48 h using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF) MS systems (VITEK^®MS-bioMérieux) and standard microbiological procedures (VITEK^®2 NH ID card-bioMérieux). Both methods identified the strain as N. meningitidis. The meningococcal isolate belonged to the serogroup B (MenB), Sequence type (ST)-162/clonal complex (cc)162. Two grams of ceftriaxone twice a day were administered for 21 days; than cefditoren pivoxil 400 mg twice a day for further 6 weeks after discharge. In Italy, from 2018 to January 2022, among 135 MenB, 31 MenB/cc162 were identified, of which only the case here reported was associated with an atypical clinical presentation.

REVIEW OF THE LITERATURE

A total of 41 cases of PMA caused by N. meningitidis was reported in the literature, but only four occurred in elderly. To our knowledgements, no cases of PMA caused by MenB were previously reported among patients of more than 65 years of age.

A Metatranscriptomics Survey of Microbial Diversity on Surfaces Post-Intervention of cleanSURFACES® Technology in an Intensive Care Unit

Hospital-acquired infections (HAIs) pose a serious threat to patients, and hospitals spend billions of dollars each year to reduce and treat these infections. Many HAIs are due to contamination from workers’ hands and contact with high-touch surfaces. Therefore, we set out to test the efficacy of a new preventative technology, AIONX^® Antimicrobial Technologies, Inc’s cleanSURFACES^®, which is designed to complement daily chemical cleaning events by continuously preventing re-colonization of surfaces. To that end, we swabbed surfaces before (Baseline) and after (Post) application of the cleanSURFACES^® at various time points (Day 1, Day 7, Day 14, and Day 28). To circumvent limitations associated with culture-based and 16S rRNA gene amplicon sequencing methodologies, these surface swabs were processed using metatranscriptomic (RNA) analysis to allow for comprehensive taxonomic resolution and the detection of active microorganisms. Overall, there was a significant (P < 0.05) global reduction of microbial diversity in Post-intervention samples. Additionally, Post sample microbial communities clustered together much more closely than Baseline samples based on pairwise distances calculated with the weighted Jaccard distance metric, suggesting a defined shift after product application. This shift was characterized by a general depletion of several microbes among Post samples, with multiple phyla also being reduced over the duration of the study. Notably, specific clinically relevant microbes, including Staphylococcus aureus, Clostridioides difficile and Streptococcus spp., were depleted Post-intervention. Taken together, these findings suggest that chemical cleaning events used jointly with cleanSURFACES^® have the potential to reduce colonization of surfaces by a wide variety of microbes, including many clinically relevant pathogens.

A tale of two unusual anaerobic bacterial infections in an immunocompetent man: A case report and literature review

We report a case of an immunocompetent man who presented with Desulfovibrio fairfieldensis bacteremia, followed by an epidural abscess due to Parvimonas micra. Only few cases have described unique clinical features related to both organisms, and this report illustrates two distinct sequential, if not concurrent, syndromes due to these anaerobes.

Late onset prosthetic joint infection caused by Parvimonas micra

Parvimonas micra (P.micra) is a difficult to culture gram positive anaerobic microorganism, typically found in the human microbiota, specially in the oral cavity. There are limited cases in literature reporting prosthetic joint infection due to this bacteria, although its isolation has been reported in different settings in later years. We present the case of a late onset knee prosthetic joint infection caused by Parvimonas micra in an 87 year old woman treated with antibiotics and two-step surgery with prosthetic material removal, antibiotic-loaded cement spacer placement and new prosthetic material replacement after 2 weeks of intravenous antimicrobial therapy followed by 6 weeks of oral therapy.

Native joint infections caused by Parvimonas micra

Parvimonas micra is an anaerobic, fastidious, gram positive organism commonly found in the oral cavity and gastrointestinal tract. It has been increasingly reported as the cause of septic arthritis of native joints, often times with delayed diagnosis leading to increased morbidity. Risk factors include immunosuppression, inflammation of the joint, and recent dental procedures or infections. It has been a historically difficult organism to culture. However, the development of and increasing use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) has led to increased identification of P. micra. Common antibiotic susceptibilities, as well as data regarding susceptibilities in specific situations, have been reported, but susceptibility testing is required in all cases. Common treatments include clindamycin, penicillin, and metronidazole for six to ten weeks.

Parvimonas micra causing native hip joint septic arthritis

Parvimonas micra is a bacterium normal to oral and gastrointestinal flora that has been implicated in cases of discitis, osteomyelitis, and prosthetic joint infections, often involving dental procedures or periodontal disease. It is an extremely rare cause of infection outside of these circumstances. We describe a case of septic arthritis of the native hip joint due to P. micra.

Severe pneumonia caused by Parvimonas micra: a case report

BACKGROUND

Parvimonas micra (P. micra) is a gram-positive anaerobic coccus that is detected widely on the skin, in the oral mucosa and in the gastrointestinal tract. In certain circumstances, P. micra can cause abdominal abscesses, bacteraemia and other infections. To the best of our knowledge, there have been no case reports describing the biological characteristics of P. micra-related pneumonia. These bacteria do not always multiply in an aerobic organ, such as the lung, and they could be easily overlooked because of the clinical mindset.

CASE PRESENTATION

A 35-year-old pregnant woman was admitted to the emergency department 4 weeks prior to her due date who was exhibiting 5 points on the Glasgow coma scale. A computed tomography (CT) scan showed a massive haemorrhage in her left basal ganglia. She underwent a caesarean section and brain surgery before being admitted to the ICU. She soon developed severe pneumonia and hypoxemia. Given that multiple sputum cultures were negative, the patient's bronchoalveolar lavage fluid was submitted for next-generation sequencing (NGS) to determine the pathogen responsible for the pneumonia; as a result, P. micra was determined to be the causative pathogen. Accordingly the antibiotic therapy was altered and the pneumonia improved.

CONCLUSION

In this case, we demonstrated severe pneumonia caused by the anaerobic organism P. micra, and the patient benefited from receiving the correct antibiotic. NGS was used as a method of quick diagnosis when sputum culture failed to distinguish the pathogen.

An uncommon case of native joint septic arthritis by Parvimonas micra

Parvimonas micra is an anaerobic, Gram-positive coccus found in the oral cavity and gastrointestinal tract. We report a case of a 77-year-old male with right knee pain after a recent dental procedure and fall. Arthrocentesis was notable for Parvimonas micra which was successfully treated with metronidazole.

Gastric cancer: a comprehensive review of current and future treatment strategies

Gastric cancer remains a major unmet clinical problem with over 1 million new cases worldwide. It is the fourth most commonly occurring cancer in men and the seventh most commonly occurring cancer in women. A major fraction of gastric cancer has been linked to variety of pathogenic infections including but not limited to Helicobacter pylori (H. pylori) or Epstein Barr virus (EBV). Strategies are being pursued to prevent gastric cancer development such as H. pylori eradication, which has helped to prevent significant proportion of gastric cancer. Today, treatments have helped to manage this disease and the 5-year survival for stage IA and IB tumors treated with surgery are between 60 and 80%. However, patients with stage III tumors undergoing surgery have a dismal 5-year survival rate between 18 and 50% depending on the dataset. These figures indicate the need for more effective molecularly driven treatment strategies. This review discusses the molecular profile of gastric tumors, the success, and challenges with available therapeutic targets along with newer biomarkers and emerging targets.

Atypical Presentation of Periprosthetic Joint Infection After Total Knee Arthroplasty due to Parvimonas micra

There is limited literature reporting the oral pathogen Parvimonas micra as the causative organism of periprosthetic joint infection. Previous reports demonstrate septic arthritis in native or prosthetic joints due to P. micra in elderly or immunocompromised patients associated with tooth abscess and periodontal disease. Our case report is unique because it describes a healthy individual with recurrent gingivitis developing periprosthetic joint infection after total knee arthroplasty as the result of isolated P. micra. Her clinical symptom presented early and manifested as progressive stiffness only. Timely aspiration resulted in early diagnosis, but the patient still underwent 2-stage revision with a more constrained implant. To prevent the risk of infection by oral pathogens such as P. micra, dental history should be thoroughly investigated, and any lingering periodontal infection should be addressed before any arthroplasty operation.

Osteomyelitis of the Distal Phalanx of the Thumb due to Parvimonas micra and Fusobacterium nucleatum: A Case Report

We herein report a case of osteomyelitis of the distal phalanx of the thumb of a 55-year-old man caused by Parvimonas micra and Fusobacterium nucleatum. Osteomyelitis often occurs in long bones and rarely occurs in the bones of the fingers. In addition, osteomyelitis of the finger frequently occurs after trauma or surgery, and blood-borne infection is very rare. P. micra and F. nucleatum, normal flora of the oral cavity, are very rare pathogenic bacteria of osteomyelitis except in periodontal disease, and there are no previous reports regarding the occurrence of osteomyelitis due to P. micra and F. nucleatum in the finger bones.

Alteration of the abundance of Parvimonas micra in the gut along the adenoma-carcinoma sequence

Parvimonas micra (P. micra) is reported to be associated with colorectal cancer (CRC). However, its association with colorectal adenoma (CRA) and its role in the initiation of colorectal tumors remain unknown. The present study aimed to clarify the relationship between P. micra and CRA and CRC by exploring the changes of P. micra abundance in an adenoma-carcinoma sequence in a new cohort and 4 public sequencing datasets. To investigate the alterations of P. micra abundance in the gut along the adenoma-carcinoma sequence, quantitative PCR (qPCR) was conducted to measure the relative abundance of P. micra in fecal samples from 277 subjects (128 patients with CRA, 66 patients with CRC and 83 healthy individuals, as controls) who underwent colonoscopy as outpatients. Then, the relative abundance of P. micra was analyzed in fecal samples from 596 subjects (185 healthy controls, 158 CRC, 253 CRA) in four public 16S rRNA sequencing datasets. The qPCR results demonstrated that the CRA group had an abundance of P. micra (P=0.2) similar to that of the healthy control group, while the CRC group had a significantly increased abundance (P=8.2×10⁻¹¹). The level of P. micra effectively discriminated patients with CRC from healthy controls, while it poorly discriminated patients with CRA from healthy controls; with an area under the receiver operating characteristic curve of 0.867 for patients with CRC and 0.554 for patients with CRA. The same pattern of the alteration of P. micra abundance, which was low in healthy controls and patients with CRA but elevated in patients with CRC, was found in all four public sequencing datasets. These results suggested that P. micra was closely associated with, and may serve as a diagnostic marker for, CRC but not CRA. Moreover, it was indicated that P. micra may be an opportunistic pathogen of CRC, which may promote CRC development but serve a limited role in tumorigenesis.

The Versatility of Opportunistic Infections Caused by Gemella Isolates Is Supported by the Carriage of Virulence Factors From Multiple Origins

The molecular basis of the pathogenesis of the opportunistic invasive infections caused by isolates of the Gemella genus remains largely unknown. Moreover, inconsistencies in the current species assignation were detected after genome-level comparison of 16 public Gemella isolates. A literature search detected that, between the two most pathogenic species, Gemella morbillorum causes about twice the number of cases compared to Gemella haemolysans. These two species shared their mean diseases - sepsis and endocarditis - but differed in causing other syndromes. A number of well-known virulence factors were harbored by all species, such as a manganese transport/adhesin sharing 83% identity from oral endocarditis-causing streptococci. Likewise, all Gemellae carried the genes required for incorporating phosphorylcholine into their cell walls and encoded some choline-binding proteins. In contrast, other proteins were species-specific, which may justify the known epidemiological differences. G. haemolysans, but not G. morbillorum, harbor a gene cluster potentially encoding a polysaccharidic capsule. Species-specific surface determinants also included Rib and MucBP repeats, hemoglobin-binding NEAT domains, peptidases of C5a complement factor and domains that recognize extracellular matrix molecules exposed in damaged heart valves, such as collagen and fibronectin. Surface virulence determinants were associated with several taxonomically dispersed opportunistic genera of the oral microbiota, such as Granulicatella, Parvimonas, and Streptococcus, suggesting the existence of a horizontally transferrable gene reservoir in the oral environment, likely facilitated by close proximity in biofilms and ultimately linked to endocarditis. The identification of the Gemella virulence pool should be implemented in whole genome-based protocols to rationally predict the pathogenic potential in ongoing clinical infections caused by these poorly known bacterial pathogens.

Brain abscess in a patient with psoriatic arthritis treated with adalimumab: A case report

RATIONALE

In patients receiving biological therapies, serious infections are a major concern. Infections associated with anti-tumor necrosis factor antibody therapy include tuberculosis, viral, fungal, and bacterial infections. Likewise, severe infections of the upper and lower respiratory tract, lung, skin and soft tissue, urinary tract, gastrointestinal tract, joint, and bone have also been reported previously. However, infections involving the central nervous system are rare, especially an intracranial infection caused by odontogenic infection. To date, only few cases have been reported of this infection. This is the first case of a patient with psoriatic arthritis receiving adalimumab and developing brain abscess of odontogenic origin.

PATIENT CONCERNS

A 39-year-old male with psoriatic arthritis receiving adalimumab treatment came to the emergency department with initial presentation of sudden onset convulsions. He had been receiving adalimumab treatment for 1 month. Two days after the third injection, the patient had an episode of sudden-onset general convulsion for nearly 5 min with the upgazing and general tonic presentation. Magnetic resonance imaging (MRI) showed left frontal lobe brain abscess. Pus culture from the brain abscess detected Streptococcus sanguinis (S. sanguinis), Fusobacterium nucleatum (F. nucleatum), and Parvimonas micra (P. micra).

DIAGNOSIS

Brain abscess with odontogenic infection.

INTERVENTIONS

The patient received left frontal craniotomy, abscess drainage and systemic empiric antibiotics treatment with vancomycin, cefepime, and metronidazole. Due to drug rash with eosinophilia and systemic symptoms during the treatment, vancomycin and metronidazole were discontinued, and systemic antibiotics were switched to teicoplanin and ceftriaxone.

OUTCOMES

A brain MRI follow-up performed after 1 month of initial treatment revealed the reduced size of the abscess lesion and minimal oedema. The patient was discharged with stable condition.

LESSONS

To the best of our knowledge, this is the first case of a patient with psoriatic arthritis receiving adalimumab and developing brain abscess of odontogenic origin. Such a rare diagnosis must be kept in mind when patients treated with adalimumab present with sudden-onset convulsions. Careful dental examination should be performed before administration of adalimumab.

Electrospun PLA Fibers Containing Metronidazole for Periodontal Disease

Purpose

Electrospun PLA fiber devices were investigated in the form of fiber mats and disks. Metronidazole was used as an active agent; its concentration was 12.2 and 25.7 wt% in the devices.

Methods

The structure was studied by X-ray diffraction and scanning electron microscopy, drug release by dissolution measurements, while the antimicrobial efficiency was tested on five bacterial strains.

Results

The XRD study showed that the polymer was partially crystalline in both devices, but a part of metronidazole precipitated and was in the form of crystals among and within the fibers. Liquid penetration and dissolution were different in the two devices, they were faster in disks and slower in fiber mats, due to the morphology of the device and the action of capillary forces. Disks released the drug much faster than fiber mats. Although the release study indicated fast drug dissolution, the concentration achieved a plateau value in 24 hrs for the disks; the inhibition effect lasted much longer, 13 days for bacteria sensitive to metronidazole. The longer inhibition period could be explained by the slower diffusion of metronidazole located inside the fibers of the device.

Conclusion

The results suggest that the devices may be effective in the treatment of periodontitis.

MicroPro: using metagenomic unmapped reads to provide insights into human microbiota and disease associations

We develop a metagenomic data analysis pipeline, MicroPro, that takes into account all reads from known and unknown microbial organisms and associates viruses with complex diseases. We utilize MicroPro to analyze four metagenomic datasets relating to colorectal cancer, type 2 diabetes, and liver cirrhosis and show that including reads from unknown organisms significantly increases the prediction accuracy of the disease status for three of the four datasets. We identify new microbial organisms associated with these diseases and show viruses play important prediction roles in colorectal cancer and liver cirrhosis, but not in type 2 diabetes. MicroPro is freely available at https://github.com/zifanzhu/MicroPro .

[Periprosthetic hip-TEP infections after dental procedures : Maybe an indication for antibiotic treatment after all?]

Periprosthetic infections are hazardous complications. After dental procedures, an antibiotic prophylaxis or treatment is actually not recommended according to the current guidelines. In the present work, a case of a hematogenous late infection after primary total hip arthroplasty due to a prior dental procedure is presented. Hereby, the question evolves as to whether in selected cases an antibiotic prophylaxis or treatment might be indicated at the site of dental procedures.

Early Hip Arthroscopy for Femoroacetabular Impingement Syndrome Provides Superior Outcomes When Compared With Delaying Surgical Treatment Beyond 6 Months

BACKGROUND

There is literature on the association between chronic preoperative pain and worse outcomes among patients undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS). However, there are few data on whether there is an optimum window that provides the best midterm surgical outcomes.

PURPOSE

To assess the outcomes of hip arthroscopy for FAIS according to timing of surgical intervention.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients undergoing arthroscopic intervention for FAIS with a minimum 2-year follow-up were included. All patients completed the Hip Outcome Score-Activities of Daily Living (HOS-ADL), Hip Outcome Score-Sport Specific (HOS-SS), modified Harris Hip Score (mHHS), International Hip Outcome Tool-12 (iHOT-12), and visual analog scales for pain and satisfaction. Patients were stratified by preoperative symptom duration. We compared 3 to 6 months of symptoms with other subsequent time frames (>6-12, >12-24, and >24 months). Clinically significant outcome was determined with the minimal clinically important difference and patient acceptable symptomatic state.

RESULTS

A total of 1049 patients were included (mean ± SD: age, 32.3 ± 12.4 years; follow-up, 30.8 ± 6.7 months). Patients undergoing surgery at 3 to 6 months of symptoms had no significant differences in outcome when compared with those in the >6- to 12-month group except for the iHOT-12 (P = .028). Patients with symptom duration of >12 to 24 months and >24 months had worse outcomes across all measures (P < .001). Surgery within 3 to 6 months of symptoms was predictive for achieving the minimal clinically important difference on the HOS-ADL (odds ratio [OR], 1.81; 95% CI, 1.20-2.73) and HOS-SS (OR, 1.90; 95% CI, 1.11-3.17), as well as the patient acceptable symptomatic state on the HOS-ADL (OR, 1.85; 95% CI, 1.34-2.56) and HOS-SS (OR, 1.58; 95% CI, 1.14-2.18), when compared with the other groups. In multivariate regression analysis, symptom duration was predictive of visual analog scale for pain (β = 3.10; 95% CI, 1.56-4.63; P < .001) and satisfaction (β = -4.16; 95% CI, -6.14 to -2.18; P < .001).

CONCLUSION

Among patients with FAIS, surgical intervention early after the onset of symptoms (3-6 months) was associated with superior postoperative outcomes when compared with patients who underwent surgical intervention beyond this time frame. This information may help guide preoperative decision making regarding delay of surgery. These findings should be confirmed in a prospective study.

Evaluation of Predation Capability of Periodontopathogens Bacteria by Bdellovibrio Bacteriovorus HD100. An in Vitro Study

Treatment options against periodontitis attempt to completely remove oral microbiota even if several species in dental plaque demonstrate protective features. Predatory bacteria that selectively predate solely on Gram-negative bacteria might be a viable therapeutic alternative. Therefore, the aim of this study is to in vitro evaluate the susceptibility of some oral pathogens to predation by B. bacteriovorus HD100 in liquid suspension. Cultures of prey cell were prepared in brain heart infusion broth (BHI) broth incubating overnight at the appropriate conditions for each organism to reach log phase of growth. Predatory activity was assessed by measuring optical density at 600 nm after 12, 24, 48 and 72 hours. Statistical analysis was performed using the Mann-Whitney U test and p values less than 0.05 were considered statistically significant. The study demonstrated that B. bacteriovorus is able to predate on aerobic species and on microaerophilic ones (p < 0.05) but also that its predatory capacity is strongly compromised by the conditions of anaerobiosis. B. bacteriovorus, in fact, was unable to predate the anaerobic species involved in the present study (F. nucleatum and P. gingivalis). The findings of the study suggest that B. bacteriovorus is able to tolerate microaerophilic conditions and that in anaerobiosis it cannot exert its predatory capacity. Such evidence could lead to its use as an agent to prevent recolonization of the periodontal pocket following therapy. Further studies are needed to investigate the activity of B. bacteriovorus against recently recognized periodontopathogens, alone or organized in biofilms of multi-species communities.

Relationship between Gut Microbiota and Phosphorus Metabolism in Hemodialysis Patients: A Preliminary Exploration

Background

Hyperphosphatemia is a risk factor associated with mortality in patients on maintenance hemodialysis. Gut absorption of phosphate is the major source. Recent studies indicated that the intestinal flora of uremic patients changed a lot compared with the healthy population, and phosphorus is an essential element of bacterial survival and reproduction. The purpose of this study was to explore the role of intestinal microbiota in phosphorus metabolism.

Methods

A prospective self-control study was performed from October 2015 to January 2016. Microbial DNA was isolated from the stools of 20 healthy controls and 21 maintenance hemodialysis patients. Fourteen out of the 21 patients were treated with lanthanum carbonate for 12 weeks. Thus, stools were also collected before and after the treatment. The bacterial composition was analyzed based on 16S ribosomal RNA pyrosequencing. Bioinformatics tools, including sequence alignment, abundance profiling, and taxonomic diversity, were used in microbiome data analyses. Correlations between genera and the serum phosphorus were detected with Pearson's correlation. For visualization of the internal interactions and further measurement of the microbial community, SparCC was used to calculate the Spearman correlation coefficient with the corresponding P value between each two genera.

Results

Thirteen genera closely correlated with serum phosphorus and the correlation coefficient was above 0.4 (P < 0.05). We also found that 58 bacterial operational taxonomic units (OTUs) were significantly different and more decreased OTUs were identified and seven genera (P < 0.05) were obviously reduced after using the phosphate binder. Meanwhile, the microbial richness and diversity presented downward trend in hemodialysis patients compared with healthy controls and more downward trend after phosphorus reduction. The co-occurrence network of genera revealed that the network complexity of hemodialysis patients was significantly higher than that of controls, whereas treatment with lanthanum carbonate reduced the network complexity.

Conclusions

Gut flora related to phosphorus metabolism in hemodialysis patients, and improving intestinal microbiota may regulate the absorption of phosphate in the intestine. The use of phosphate binder lanthanum carbonate leads to a tendency of decreasing microbial diversity and lower network complexity.

Combination of Zinc Hyaluronate and Metronidazole in a Lipid-Based Drug Delivery System for the Treatment of Periodontitis

BACKGROUND

Despite being a highly prevalent disease and a possible contributor to adult tooth loss, periodontitis possesses no well-established therapy. The aim of the recent study was the development and evaluation of a mucoadhesive monophase lipid formulation for the sustained local delivery of amoxicillin, metronidazole, and/or zinc hyaluronate or gluconate.

METHODS

To investigate our formulations, differential scanning calorimetry, X-ray diffraction, swelling, erosion, mucoadhesivity, drug release, and antimicrobial measurements were performed.

RESULTS

Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) results show that the loaded drugs are in a suspended form, the softening of the formulations starts at body temperature, but a part remains solid, providing sustained release. Swelling of the lipid compositions is affected by the hydrophilic components, their concentration, and the strength of the coherent lipid structure, while their erosion is impacted by the emulsification of melted lipid components.

CONCLUSIONS

Results of drug release and antimicrobial effectiveness measurements show that a sustained release may be obtained. Amoxicillin had higher effectiveness against oral pathogens than metronidazole or zinc hyaluronate alone, but the combination of the two latter could provide similar effectiveness to amoxicillin. The applied mucoadhesive polymer may affect adhesivity, drug release through the swelling mechanism, and antimicrobial effect as well.

Parvimonas micra bacteremia following endoscopic retrograde cholangiopancreatography: A new route of infection

Parvimonas micra is an anaerobic, Gram-positive coccus belonging to oral, gastrointestinal and genital flora, rarely causing infections in humans. It was mainly deemed to cause bacteremia, septic bone and cerebral infections in patients which have undergone dental procedures or with suboptimal dental hygiene. We report the first case of Parvimonas micra bacteremia following endoscopic retrograde colangiopancreatography performed due to choledocholithiasis in a patient with good oral health. Identification of P. micra was finally performed by Matrix-assisted laser desorption ionization-time of flight mass spectrometry (VITEK MS system, bioMérieux, Marcy l'Étoile, France). All cases reported in english language of Parvimonas micra infections after medical procedure are reviewed in order to alert clinicians about new possible routes of infection of this emerging pathogen.

Gut Microbiome Analysis Identifies Potential Etiological Factors in Acute Gastroenteritis

The morbidity and mortality resulting from acute gastroenteritis and associated chronic sequelae represent a substantial burden on health care systems worldwide. Few studies have investigated changes in the gut microbiome following an episode of acute gastroenteritis. By using nondirected 16S rRNA gene amplicon sequencing, the fecal microbiota of 475 patients with acute gastroenteritis was examined. Patient age was correlated with the overall microbial composition, with a decrease in the abundance of Faecalibacterium being observed in older patients. We observed the emergence of a potential Escherichia-Shigella-dominated enterotype in a subset of patients, and this enterotype was predicted to be more proinflammatory than the other common enterotypes, with the latter being dominated by Bacteroides or Faecalibacterium The increased abundance of Escherichia-Shigella did not appear to be associated with infection with an agent of a similar sequence similarity. Stool color and consistency were associated with the diversity and composition of the microbiome, with deviations from the norm (not brown and solid) showing increases in the abundances of bacteria such as Escherichia-Shigella and Veillonella Analysis of enriched outliers within the data identified a range of genera previously associated with gastrointestinal diseases, including Treponema, Proteus, Capnocytophaga, Arcobacter, Campylobacter, Haemophilus, Aeromonas, and Pseudomonas Our data represent the first in-depth analysis of gut microbiota in acute gastroenteritis. Phenotypic changes in stool color and consistency were associated with specific changes in the microbiota. Enriched bacterial taxa were detected in cases where no causative agent was identified by using routine diagnostic tests, suggesting that in the future, microbiome analyses may be utilized to improve diagnostics.

Acute septic arthritis of the knee: A rare case report of infection with Parvimonas micra after an intra-articular corticosteroid injection for osteoarthritis

Acute bacterial mono-articular septic arthritis affects most commonly the lower extremity joints in adult population and most commonly caused by Staphylococcus aureus. Various risk factors determine susceptibility to infection including host immunity, medical co-morbidity and joint structural abnormality and other organisms may be involved. Parvimonas micra (P. micra) is among the rare organisms that may be associated with atypical septic arthritis and primarily affects the native knee joint. Only 3 case reports in the literature have reported on pyogenic pyogenic joint infection caused by this organism. We hereby present our experience with a case of knee septic arthritis caused by P. micra in a patient with knee osteoarthritis following a recent intra-articular injection with corticosteroids. In susceptible patients, Intra-articular corticosteroid injection and crystal induced arthritis may propose a potential risk of contracting infection with P. micra.

Septic arthritis of knee joint due to Parvimonas micra

Parvimonas species are anaerobic, Gram-positive cocci that are a constituent of normal oral and gastrointestinal flora. We present a case of right knee joint septic arthritis due to Parvimonas micra in an immunocompromised patient. A 61-year-old male renal and pancreatic transplant recipient on immunosuppressive therapy was admitted to our hospital due to intense pain, joint swelling and inability to move his right knee over the past 9 months. After synovial fluid was drawn, cultures were positive for P. micra, an anaerobic pathogen that is part of the flora of the oral cavity. We report a rare causative pathogen for septic arthritis in an immunocompromised patient.

The combined and individual impact of diabetes and smoking on key subgingival periodontal pathogens in patients with chronic periodontitis

BACKGROUND AND OBJECTIVE

Comprehension of the similarities and differences in the composition of the subgingival microbiota of patients with diabetes mellitus (DM), smokers or smokers with DM is an important step in developing therapies specific for these groups at risk for periodontitis. Therefore, the aim of this study was to compare the combined and individual effects of DM and smoking on the levels and prevalence of key subgingival periodontal pathogens in patients with chronic periodontitis.

MATERIAL AND METHODS

One hundred patients with generalized chronic periodontitis were allocated into one of the following groups: DM (n = 25, non-smokers with type 2 DM); S (n = 25, non-diabetic smokers); SDM (n = 25, smokers with type 2 DM); and control (n = 25, non-diabetic non-smokers). Two subgingival biofilm samples from healthy sites (probing depth and clinical attachment level ≤3 mm and no bleeding) and 2 from diseased sites (probing depth and clinical attachment level ≥5 mm and bleeding on probing) were analyzed by quantitative polymerase chain reaction for Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Eubacterium nodatum, Parvimonas micra, Fusobacterium nucleatum ssp. and Prevotella intermedia.

RESULTS

There were no differences among groups in the mean counts of the bacterial species studied, considering all sampled sites (healthy plus diseased sites). There were also no differences among groups regarding the prevalence of any bacteria species in healthy and diseased sites (P > .05). The mean P. micra count was significantly higher in the healthy sites of both smoking groups, than in those of the control group (P < .05).

CONCLUSION

The subgingival levels and prevalence of the bacterial species studied are not significantly different in subjects with chronic periodontitis presenting DM, smokers or smokers with DM. In addition, DM and smoking, jointly and individually, do not considerably affect the subgingival levels of target periodontal pathogens in patients with chronic periodontitis.

Cyclic Dinucleotides in Oral Bacteria and in Oral Biofilms

Oral cavity acts as a reservoir of bacterial pathogens for systemic infections and several oral microorganisms have been linked to systemic diseases. Quorum sensing and cyclic dinucleotides, two "decision-making" signaling systems, communicate to regulate physiological process in bacteria. Discovery of cyclic dinucleotides has a long history, but the progress in our understanding of how cyclic dinucleotides regulate bacterial lifestyle is relatively new. Oral microorganisms form some of the most intricate biofilms, yet c-di-GMP, and c-di-AMP signaling have been rarely studied in oral biofilms. Recent studies demonstrated that, with the aid of bacterial messenger molecules and their analogs, it is possible to activate host innate and adaptive immune responses and epithelial integrity with a dose that is relevant to inhibit bacterial virulence mechanisms, such as fimbriae and exopolysaccharide production, biofilm formation, and host cell invasion. The aim of this perspective article is to present available information on cyclic dinucleotides in oral bacteria and in oral biofilms. Moreover, technologies that can be used to detect cyclic dinucleotides in oral biofilms are described. Finally, directions for future research are highlighted.

Acute Mono-Arthritis of the Knee: A Case Report of Infection with Parvimonas Micra and Concomitant Pseudogout

Parvimonas micra is a rare pathogen for septic arthritis and is known for its subacute onset. We report a case of acute arthritis of the knee caused by P. micra and pseudogout. Initially, calcium pyrophosphate crystals were found in the knee, which were successfully treated with a steroid injection. Only anaerobic cultures became positive. A 16S rRNA PCR-analysis was necessary to identify P. micra as causative agent, a method which is never described before in similar cases. The infection was treated with clindamycin for 6 weeks. This is the third case report of a septic arthritis caused by P. micra and the second which also reports concomitant pseudogout.