Actinomycotic osteomyelitis of the maxilla in a female patient: A rare case report with the review of the literature

Actinomycotic osteomyelitis is a rare chronic suppurative, granulomatous, fibrosing saprophytic infection. It is an endogenous infection caused by the Actinomyces species, which are part of the normal oral microflora. There is a male predilection for this type of infection, with the male to female ratio of 4:1. Though the etiopathogenesis of the infection is unclear, it is mostly attributed to the disruption of the normal oral microflora and the invasion of the microorganism into deeper tissues through a break in the mucosal barrier due to damage from trauma, extraction or previous injury. The portal of entry can be through the pulpal, periodontal or mucosal route, causing the purulent and necrotic infection of soft tissue, bone, or both. The diagnosis is usually considered when there is a persistent infection without the presence of regional lymphadenopathy and is usually confirmed through the histopathological depiction of the bacterial colonies - 'ray fungus' - as obtaining the positive culture of the causative microorganisms is difficult and is reported to be effective in less than 50%. Patients with such infections are managed with surgical debridement, followed by antibiotic therapy for a longer time period. Recent advances have been emphasized for an early diagnosis and a better prognosis of the therapy. Therefore, this paper aimed to present a rare case of actinomycotic osteomyelitis of the maxilla in a 45-year-old female patient, and also to review the literature on this rare infection.

Persistent Multispecies Actinomyces Mastitis Treated With Repeated Aspiration and Long-Term Oral Antibiotics

Actinomycosis is an infection characterized by abscess formation, draining sinuses, and tissue fibrosis. The causative bacterium is a Gram-positive facultative anaerobe from the genus Actinomyces. Infections classically affect the cervicofacial, thoracic, or pelvic region and often require prolonged antibiotic therapy. Actinomycosis of the breast is a rare condition that may present as a recurrent breast abscess. We present a 33-year-old female with a recurrent breast abscess which grew A. radingae and A. israeli on aspirated fluid cultures. Treatment with surgical aspiration and a 6-week course of oral amoxicillin/clavulanic acid 875 mg twice daily resulted in clinical improvement. Our case demonstrates how recurrent breast abscesses caused by Actinomyces can be difficult to manage. Long-term antibiotic therapy with surgical aspiration and regular follow-up offer the best chance of clinical resolution.

Elevated dietary carbohydrate and glycemic intake associate with an altered oral microbial ecosystem in two large U.S. cohorts

The human oral microbiome is associated with chronic diseases including cancer. However, our understanding of its relationship with diet is limited. We assessed the associations between carbohydrate and glycemic index (GI) with oral microbiome composition in 834 non-diabetic subjects from the NCI-PLCO and ACS-CPSII cohorts. The oral microbiome was characterized using 16Sv3-4 rRNA-sequencing from oral mouthwash samples. Daily carbohydrate and GI were assessed from food frequency questionnaires. We used linear regression, permutational MANOVA, and negative binomial Generalized Linear Models (GLM) to test associations of diet with α- and β-diversity and taxon abundance (adjusting for age, sex, cohort, BMI, smoking, caloric intake, and alcohol). A q-value (FDR-adjusted P-value) of <0.05 was considered significant. Oral bacterial α-diversity trended higher in participants in the highest quintiles of carbohydrate intake, with marginally increased richness and Shannon diversity (p-trend=0.06 and 0.07). Greater carbohydrate intake was associated with greater abundance of class Fusobacteriia (q=0.02) and genus Leptotrichia (q=0.01) and with lesser abundance of an Actinomyces OTU (q=4.7E-04). Higher GI was significantly related to greater abundance of genus Gemella (q=0.001). This large, nationwide study provides evidence that diets high in carbohydrates and GI may influence the oral microbiome.

Actinomyces in Forensic Practice

ABSTRACT

A 19-year-old woman in septic shock with recent computed tomography findings of a loculated hepatic abscess was transferred to an intensive care unit where she went into asystolic cardiac arrest. After resuscitation, surgical exploration revealed a purulent pericardial effusion with tamponade and a liver abscess. Microbiological analyses from both sites were negative. Shortly after surgical exploration, she developed multiorgan failure and died. At autopsy, pus was observed both within the pericardial cavity and around the left lobe of the liver. Green "sulfur granules" suggestive of infection with Actinomyces spp. were able to be extruded from the liver during the postmortem examination and cultures returned positive for Actinomyces israelii. This case is a rare example of primary hepatic actinomycosis infection that resulted in the death of a young woman. Nonspecific clinical manifestations may delay diagnosis; however, the finding of "sulfur granules" in areas of abscess formation at autopsy should be taken as an indication of possible underlying Actinomyces infection.

Vaginal estrogen therapy is associated with increased Lactobacillus in the urine of postmenopausal women with overactive bladder symptoms

BACKGROUND

Previous work has shown that the vaginal microbiome decreases in Lactobacillus predominance and becomes more diverse after menopause. It has also been shown that estrogen therapy restores Lactobacillus dominance in the vagina and that topical estrogen is associated with overactive bladder symptom improvement. We now know that the bladder contains a unique microbiome and that increased bladder microbiome diversity is associated with overactive bladder. However, there is no understanding of how quickly each pelvic floor microbiome responds to estrogen or if those changes are associated with symptom improvement.

OBJECTIVE

This study aimed to determine if estrogen treatment of postmenopausal women with overactive bladder decreases urobiome diversity.

STUDY DESIGN

We analyzed data from postmenopausal participants in 2 trials (NCT02524769 and NCT02835846) who chose vaginal estrogen as the primary overactive bladder treatment and used 0.5 g of conjugated estrogen (Premarin cream; Pfizer, New York City, NY) twice weekly for 12 weeks. Baseline and 12-week follow-up data included the Overactive Bladder questionnaire, and participants provided urine samples via catheter, vaginal swabs, perineal swabs, and voided urine samples. Microbes were detected by an enhanced culture protocol. Linear mixed models were used to estimate microbiome changes over time. Urinary antimicrobial peptide activity was assessed by a bacterial growth inhibition assay and correlated with relative abundance of members of the urobiome.

RESULTS

In this study, 12 weeks of estrogen treatment resulted in decreased microbial diversity within the vagina (Shannon, P=.047; Richness, P=.043) but not in the other niches. A significant increase in Lactobacillus was detected in the bladder (P=.037) but not in the vagina (P=.33), perineum (P=.56), or voided urine (P=.28). The change in Lactobacillus levels in the bladder was associated with modest changes in urgency incontinence symptoms (P=.02). The relative abundance of the genus Corynebacterium correlated positively with urinary antimicrobial peptide activity after estrogen treatment.

CONCLUSION

Estrogen therapy may change the microbiome of different pelvic floor niches. The vagina begins to decrease in diversity, and the bladder experiences a significant increase in Lactobacillus levels; the latter is correlated with a modest improvement in the symptom severity subscale of the Overactive Bladder questionnaire.

Pulmonary actinomycosis diagnosed by radial endobronchial ultrasound coupled with metagenomic next-generation sequencing: A case report and brief literature review

Pulmonary actinomycosis (PA) is an uncommon pulmonary infectious disease that often is misdiagnosed. Metagenomic next-generation sequencing (mNGS) is a highly sensitive and culture-independent new molecular technology for precise infectious disease diagnosis. Here we report a PA case diagnosed by the combination of a radial endobronchial-ultrasonography guide sheath (R-EBUS-GS) and mNGS, along with a brief review of the literature.

[Our experiences with Actinomyces urogenitalis in human clinical samples]

Actinomyces urogenitalis is most commonly associated with the human genitourinary system, often only as the resident flora. Outside the genitourinary tract, A. urogenitalis is isolated rather sporadically. Presented are two brief case reports of human infections outside the genitourinary tract as well as experiences with microbiological identification of this actinomycete. Antibiotic susceptibility testing of actinomycetes is focused especially on their resistance to lincosamides and fluoroquinolones. The etiological relationship with the patients' clinical problems was not investigated. Previously reported cases of infections outside the genitourinary tract are also mentioned in the article. The article may aid in expanding the knowledge of the occurrence, diagnosis and susceptibility of A. urogenitalis to antibiotics, particularly in rarely reported extra-genitourinary infections caused by this species. Accurate species identification in routine laboratory practice is important both for determination of the etiological role of the microorganism and for more precise selection of empirical antibiotic therapy.

[Thoracal actinomycosis - a diagnostic challenge]

Actinomycotic infection of the chest structures is rare but can be serious. Diagnosis is difficult, since both culture of the bacterium and pathological investigation require special methods. Investigations therefore usually take many months before the correct treatment can be started. The most common differential diagnosis is a chest malignancy. Treatment is long-term antibiotics. We here present three cases which illustrate the clinical and radiological findings and the diagnostic difficulties.

Lung abscess by Actinomyces odontolyticus and Parvimonas micra co-infection presenting as acute respiratory failure: A case report

RATIONALE

Actinomyces odontolyticus and Parvimonas micra are very rare causative organisms of lung abscess and acute respiratory failure.

PATIENT CONCERNS

A 49-year-old male patient visited the emergency room with a complaint of sudden onset of shortness of breath, and he developed acute respiratory failure rapidly.

DIAGNOSIS

An abscess in the left lower lung field was diagnosed on the computed tomography scan of chest.

INTERVENTIONS

Immediate treatment with intravenous antibiotics was initiated along with a pigtail catheter insertion for pus drainage.

OUTCOMES

A odontolyticus was cultured on the drained pus and P micra was identified by a blood culture. The patient was successfully weaned from the mechanical ventilator and the lung abscess was completely resolved.

LESSONS

To the best of our knowledge, this is the first case report of mixed infection with A odontolyticus and P micra, which caused acute respiratory failure in an immune-competent patient. Therefore, physicians should consider the possibility of these organisms as causative pathogens of a fulminant pulmonary infection even in an immune-competent patient.

Rapid evolution of decreased host susceptibility drives a stable relationship between ultrasmall parasite TM7x and its bacterial host

Around one-quarter of bacterial diversity comprises a single radiation with reduced genomes, known collectively as the Candidate Phyla Radiation. Recently, we coisolated TM7x, an ultrasmall strain of the Candidate Phyla Radiation phylum Saccharibacteria, with its bacterial host Actinomyces odontolyticus strain XH001 from human oral cavity and stably maintained as a coculture. Our current work demonstrates that within the coculture, TM7x cells establish a long-term parasitic association with host cells by infecting only a subset of the population, which stay viable yet exhibit severely inhibited cell division. In contrast, exposure of a naïve A. odontolyticus isolate, XH001n, to TM7x cells leads to high numbers of TM7x cells binding to each host cell, massive host cell death, and a host population crash. However, further passaging reveals that XH001n becomes less susceptible to TM7x over time and enters a long-term stable relationship similar to that of XH001. We show that this reduced susceptibility is driven by rapid host evolution that, in contrast to many forms of phage resistance, offers only partial protection. The result is a stalemate where infected hosts cannot shed their parasites; nevertheless, parasite load is sufficiently low that the host population persists. Finally, we show that TM7x can infect and form stable long-term relationships with other species in a single clade of Actinomyces, displaying a narrow host range. This system serves as a model to understand how parasitic bacteria with reduced genomes such as those of the Candidate Phyla Radiation have persisted with their hosts and ultimately expanded in their diversity.

Actinomyces tangfeifanii sp. nov., isolated from the vulture Aegypius monachus

A novel, Gram-stain-positive, catalase-positive, non-spore-forming, short rod-shaped strain (VUL4_3^T) was isolated from rectal swabs of Old World vultures (Aegypius monachus) from the Tibet-Qinghai Plateau, China. Based on the results of biochemical tests and 16S rRNA gene sequence comparison, strain VUL4_3^T was determined to be a member of the genus Actinomyces that is closely related to the type strains of Actinomyces liubingyangii (97.7 % 16S rRNA gene sequence similarity) and Actinomyces marimammalium (96.5 %). Optimal growth occurred at 37 °C, pH 6-7 and with 1 % (w/v) NaCl. The typical major cellular fatty acids of strain VUL4_3^T were C18 : 1ω9c, C16 : 0 and C18 : 0. The VUL4_3^T genome contained 2 207 832 bp with an average G+C content of 51.9 mol%. DNA-DNA hybridization values between strain VUL4_3^T and the above two species of the genus Actinomyces showed less than 32 % DNA-DNA relatedness, supporting a novel species status of strain VUL4_3^T. Based on the phenotypic data and phylogenetic inference, the novel species Actinomycestangfeifanii sp. nov. is proposed. The type strain is VUL4_3^T (=CGMCC 4.7369^T=DSM 103436^T).

[Primary intestinal actinomycosis in ilium and colon. A case report and review of the literature]

Actinomycosis is a chronic, suppurative, inflammatory granulomatous disease caused by gram positive anaerobic filamentous bacteria of the genus Actinomyces, most frequently Actinomyces israelii. We report a case of a 42-year-old male presenting with abdominal pain, a 10kg weight loss and a fixed mass in the epigastrium. Tomography revealed dilatation of the intestinal loops and thickening of the colon walls; the coexistence of these two findings suggested a lymphoproliferative process. The tumour, ileum fragment and colon were surgically removed; these were adherent to the serosal fibro-adipose tissue. Microscopically, abundant polymorphonuclear infiltrate and grains of bacteria compatible with Actinomyces spp.were seen.

Pott's puffy tumor by Actinomyces after minor head trauma

Pott's puffy tumour (PPT) is a rare entity that involves scalp swelling associated with subperiosteal abscess and cranial osteomyelitis, occasionally accompanied by intracranial infection. It is usually affiliated with frontal sinusitis, which is a typical but infrequent complication. On the contrary, Osteomyelitis by Actinomyces is rare and usually occurs at the mandibular level, with very few cases of cranial osteomyelitis caused by this bacterial specie, especially after traumatic brain injury. We report an exceptionally unusual case of a PPT frontal tumor after blunt trauma (closed head injury), with an intracranial lesion whereby Actinomyces was isolated after surgery, as a co-participant of the mentioned infection besides Fusobacterium and Propionibacterium.

Recurrent Pilonidal Sinus Cyst on Penis

Pilonidal sinus, including one or more sinus canals and hairs, is a disease with a chronic course showing acute attacks which is often encountered in the general population, usually affecting young adults, at a rate in males twice that of females. Pilonidal sinus on the penis is so rare that very few cases have been reported in literature. A 20-year-old male presented to the urology outpatient clinic with the complaint of a suppurative lesion with discharge on the skin of the penis which had been ongoing for approximately three months. Clinical examination revealed an indurated, erythematous, ulcerative lesion, 3 cm x 2 cm in size, in the middle of the ventral aspect of the penile shaft. We present the first case in literature of recurrent pilonidal sinus related to Actinomyces israelii, located on the penis.

Pelvic actinomycosis and IUD

OBJECTIVE

To summarize knowledge about the mana-gement in women with proven actinomyces in uterine cervix and inserted intrauterine device (IUD).

DESIGN

An overall review.

RESULTS

Actinomycosis is an uncommon but important subacute or chronic infection caused by anaerobic or microaerophilic bacteria, mainly within the Actinomyces genus. Actinomycosis can affect various organs and tissues in the human body, often manifesting draining sinuses, abscess formation and fibrosis. The pelvic form in women is the most common in the developed countries. Long-duration treatment with antibiotics can be completely effective even in cases of heavy disease. Although pelvic actinomycosis is predominantly associated with the longstanding use of intrauterine device, the risk of future symptomatic infection is extremly low even in women with a cervical Pap smear positive for actinomyces-like organisms (ALO). Therefore the identification of actinomycetes by cytology after cervical Pap smears is not diagnostic nor predictive of any disease because the actinomycetes normally reside in the female genital tract. In the absence of symptoms, patients with ALO on a Pap test do not need antimicrobial treatment or IUD removal. Nevertheless, women choosing an IUD for contraception should know that there is very low risk of developing the infection in later years after insertion.

CONCLUSION

The sources of literature conclude that removal of the intrauterine device in a patients with a positive ALO in the uterine cervix is not necessary and antibiotics treatment is not required. However, IUD must be changed at least every five years in order to limit the risk of the development of pelvic actinomycosis.

Evaluation of the bioactive extract of actinomyces isolated from the Egyptian environment against aflatoxin B1-induce cytotoxicity, genotoxicity and oxidative stress in the liver of rats

This study aimed to determine the bioactive compounds of actinomyces (ACT) isolated from the Egyptian environment (D-EGY) and to evaluate their protective activity against AFB₁ in female Sprague-Dawley rats. Six groups of animals were treated orally for 3 weeks included: C, the control group, T1, AFB₁-treated group (80 μg/kg b.w), T2 and T3, the groups received ACT extract at low (25 mg/kg b.w) or high (50 mg/kg b.w) doses, T4 and T5, the groups received AFB₁ plus the low or high dose of ACT extract. Blood, bone marrow and tissue samples were collected for different analyses and histological examination. The results revealed the identification of 40 components, representing 99.98%. Treatment with AFB₁ disturbs liver function parameters, oxidative stress markers, antioxidant gene expressions, DNA fragmentation and induced severe histological changes. ACT extract at the low or high doses did not induce significant changes in all the tested parameters or histological picture of the liver. Moreover, ACT extract succeeded to induce a significant protection against the toxicity of AFB₁. It could be concluded that the bioactive compounds in ACT are promise candidate for the development of food additive or drugs for the protection and treatment of liver disorders in the endemic area.

Betel nut chewing, oral premalignant lesions, and the oral microbiome

Oral cancers are attributed to a number of causal agents including tobacco, alcohol, human papillomavirus (HPV), and areca (betel) nut. Although betel nut chewing has been established as an independent cause of oral cancer, the mechanisms of carcinogenesis are poorly understood. An investigation was undertaken to evaluate the influence of betel nut chewing on the oral microbiome and oral premalignant lesions. Study participants were recruited from a dental clinic in Guam. Structured interviews and oral examinations were performed. Oral swabbing and saliva samples were evaluated by 454 pyrosequencing of the V3- V5 region of the 16S rRNA bacterial gene and genotyped for HPV. One hundred twenty-two adults were enrolled including 64 current betel nut chewers, 37 former chewers, and 21 with no history of betel nut use. Oral premalignant lesions, including leukoplakia and submucous fibrosis, were observed in 10 chewers. Within-sample bacterial diversity was significantly lower in long-term (≥10 years) chewers vs. never chewers and in current chewers with oral lesions vs. individuals without lesions. Between-sample bacterial diversity based on Unifrac distances significantly differed by chewing status and oral lesion status. Current chewers had significantly elevated levels of Streptococcus infantis and higher and lower levels of distinct taxa of the Actinomyces and Streptococcus genera. Long-term chewers had reduced levels of Parascardovia and Streptococcus. Chewers with oral lesions had significantly elevated levels of Oribacterium, Actinomyces, and Streptococcus, including Streptococcus anginosus. In multivariate analyses, controlling for smoking, oral HPV, S.anginosus, and S. infantis levels, current betel nut chewing remained the only predictor of oral premalignant lesions. Our study provides evidence that betel nut chewing alters the oral bacterial microbiome including that of chewers who develop oral premalignant lesions. Nonetheless, whether microbial changes are involved in betel nut-induced oral carcinogenesis is only speculative. Further research is needed to discern the clinical significance of an altered oral microbiome and the mechanisms of oral cancer development in betel nut chewers.

Salivary microbiota and caries occurrence in Mutans Streptococci-positive school children

AIM

To compare the composition of the salivary microbiota in caries-affected vs. caries-free mutans streptococci (MS)- positive children with mixed dentition.

MATERIALS AND METHODS

Twenty eight healthy, 11-12-year-old schoolchildren with high MS counts (>10⊃5 CFU/mL) were included in this study. The children were screened with the Dentocult SM Strip Mutans test (Orion Diagnostica, Espoo, Finland) and examined using the International Caries Detection and Assessment System (ICDAS). The microbial composition of the saliva was assessed using the Human Oral Microbe Identification Microarray (HOMIM). Microbial differences between caries-affected (n=18) and caries-free children (n=10) were compared by Mann-Whitney analysis.

RESULTS

The microbiota of the caries-affected vs. caries-free children was rather similar. Abiotrophia defectiva and Actinomyces meyeri/A. odontolyticus were significantly higher in caries-affected than in caries-free children (p=0.006, 0.046, respectively). Shuttleworthia satelles was significantly higher in caries-free compared to caries-affected children (p=0.031). A. defectiva and A. meyeri/A. odontolyticus correlated positively with caries severity measured by ICDAS Caries Index (p = 0.494, 0.454, 0.400 respectively) while S. satelles was negatively correlated with caries severity (p= -0.489).

CONCLUSIONS

Salivary A. defectiva and A. meyeri/A. odontolyticus and are associated with caries occurrence in MS-positive children with mixed dentition.

A Curious Case of Actinomyces Naeslundii Bacteremia in a Patient with Metastatic Pancreatic Cancer

Although considered a saprophyte, Actinomyces naeslundii can cause invasive infection leading to significant morbidity and mortality. Rarely encountered, bacteremia with this agent occurs in the setting of disrupted mucosal barriers. Previous studies suggest that actinomycosis may be a surrogate marker for poor prognosis in immunocompromised hosts. We report herein a case of a patient with metastatic pancreatic cancer who not only had a prompt resolution of Actinomyces bacteremia and a complete response to chemotherapy, but also remained disease free at 12 months after diagnosis. Our case may suggest that concomitant actinomycosis may not necessarily portend a poor prognosis in all immunocompromised patients.

A New Experimental Design for Bacterial Microleakage Investigation at the Implant-Abutment Interface: An In Vitro Study

PURPOSE

This study aimed to test bacterial microleakage at the implant-abutment interface (IAI) before and after dynamic loading using a new chewing simulation.

MATERIALS AND METHODS

Fourteen implant systems (n = 5 samples of each) were divided into two groups: (1) systems with conical implant-abutment connections (IACs), and (2) systems with flat IACs. For collecting samples without abutment disconnection, channels (Ø = 0.3 mm) were drilled into implants perpendicularly to their axes, and stainless-steel cannulas were adhesively glued inside these channels to allow a sterilized rinsing solution to enter the implant interior and to exit with potential contaminants for testing. Implants were embedded in epoxy resin matrices, which were supported by titanium cylinders with lateral openings for inward and outward cannulas. Abutments were tightened and then provided with vertically adjustable, threaded titanium balls, which were cemented using composite cement. Specimens were immersed in a bacterial liquid and after a contact time of 15 minutes, the implant interior was rinsed prior to chewing simulation (0 N ≘ static seal testing). Specimens were exposed to a Frankfurt chewing simulator. Two hundred twenty force cycles per power level (110 in ± X-axis) were applied to simulate a daily masticatory load of 660 chewing cycles (equivalent to 1,200,000 cycles/5 years). The applied load was gradually increased from 0 N to a maximum load of 200 N in 25-N increments. The implant interior was rinsed to obtain samples before each new power level. All samples were tested using fluorescence microscopy; invading microorganisms could be counted and evaluated.

RESULTS

No bacterial contamination was detected under static loading conditions in both groups. After loading, bacterial contamination was detected in one sample from one specimen in group 1 and in two samples from two specimens in group 2.

CONCLUSION

Controlled dynamic loading applied in this study simulated a clinical situation and enabled time-dependent analysis regarding the bacterial seal of different implant systems. Conical IACs offer a better bacterial seal compared with flat IACs, which showed increased microleakage after dynamic loading. IAC design plays a crucial role in terms of bacterial colonization. Taking samples of the implant interior without abutment disconnection eliminates an error source.

Clinical features of actinomycosis: A retrospective, multicenter study of 28 cases of miscellaneous presentations

Actinomycosis is a rare heterogeneous anaerobic infection with misleading clinical presentations that delay diagnosis. A significant number of misdiagnosed cases have been reported in specific localizations, but studies including various forms of actinomycosis have rarely been published.We performed a multicenter retrospective chart review of laboratory-confirmed actinomycosis cases from January 2000 until January 2014. We described clinical characteristics, diagnostic procedures, differential diagnosis, and management of actinomycosis of clinical significance.Twenty-eight patients were included from 6 hospitals in France. Disease was diagnosed predominately in the abdomen/pelvis (n = 9), orocervicofacial (n = 5), cardiothoracic (n = 5), skeletal (n = 3), hematogenous (n = 3), soft tissue (n = 2), and intracranially (n = 1). Four patients (14%) were immunocompromised. In most cases (92 %), the diagnosis of actinomycosis was not suspected on admission, as clinical features were not specific. Diagnosis was obtained from either microbiology (50%, n = 14) or histopathology (42%, n = 12), or from both methods (7%, n = 2). Surgical biopsy was needed for definite diagnosis in 71% of cases (n = 20). Coinfection was found in 13 patients (46%), among which 3 patients were diagnosed from histologic criteria only. Two-thirds of patients were treated with amoxicillin. Median duration of antibiotics was 120 days (interquartile range 60-180), whereas the median follow-up time was 12 months (interquartile range 5.25-18). Two patients died.This study highlights the distinct and miscellaneous patterns of actinomycosis to prompt accurate diagnosis and earlier treatments, thus improving the outcome. Surgical biopsy should be performed when possible while raising histologist's and microbiologist's awareness of possible actinomycosis to enhance the chance of diagnosis and use specific molecular methods.

High-throughput dental biofilm growth analysis for multiparametric microenvironmental biochemical conditions using microfluidics

Dental biofilm formation is not only a precursor to tooth decay, but also induces more serious systematic health problems such as cardiovascular disease and diabetes. Understanding the conditions promoting colonization and subsequent biofilm development involving complex bacteria coaggregation is particularly important. In this paper, we report a high-throughput microfluidic 'artificial teeth' device offering controls of multiple microenvironmental factors (e.g. nutrients, growth factors, dissolved gases, and seeded cell populations) for quantitative characteristics of long-term dental bacteria growth and biofilm development. This 'artificial teeth' device contains multiple (up to 128) incubation chambers to perform parallel cultivation and analyses (e.g. biofilm thickness, viable-dead cell ratio, and spatial distribution of multiple bacterial species) of bacteria samples under a matrix of different combinations of microenvironmental factors, further revealing possible developmental mechanisms of dental biofilms. Specifically, we applied the 'artificial teeth' to investigate the growth of two key dental bacteria, Streptococci species and Fusobacterium nucleatum, in the biofilm under different dissolved gas conditions and sucrose concentrations. Together, this high-throughput microfluidic platform can provide extended applications for general biofilm research, including screening of the biofilm properties developing under combinations of specified growth parameters such as seeding bacteria populations, growth medium compositions, medium flow rates and dissolved gas levels.

PELVIC ACTINOMYCOSIS MIMICKING A LOCALLY ADVANCED PELVIC MALIGNANCY--CASE REPORT

We present the case of a former user of an intrauterine contraceptive device (IUD) for 10 years, diagnosed with a bulky, fixed pelvic tumor involving the internal genital organs and the recto sigmoid, causing luminal narrowing of the rectum, interpreted as locally advanced pelvic malignancy, probably of genital origin. Intraoperatively, a high index of suspicion made us collect a sample from the fibrous wall of the tumor mass, large Actinomyces colonies were thus identified. Surgery consisted in debridement, removal of a small amount of pus and appendectomy, thus avoiding a mutilating and useless surgery. Specific antibiotic therapy was administered for 3 months, with favorable postoperative and long-term outcomes. Pelvic actinomycosis should always be considered in the differential diagnosis of pelvic tumors in women using an IUD. The association of long-term antibiotic treatment is essential to eradicate the infection and prevent relapses.

What is the cause of hypertrophia in asymmetric tonsils?

OBJECTIVES

Asymmetric tonsillar hypertrophy is a condition, confirmed by physical examination, that can be found in every age group. The aim of this study was to compare each tonsil through macroscopic and microscopic assessment of specimens and reveal the reasons that cause one tonsil to grow more than the other.

METHODOLOGY

The study was carried out with 93 patients who wereindicated for tonsillectomy in the authors' Clinic. Of these 93 patients, seven cases who had clinically asymmetric but pathologically symmetric tonsils were excluded from the study. The presence of microscopicintraepithelial abscess, Helicobacter pylori with Giemsa stain, Coccobacillus, fungus, Actinomyces with Pas-Grocott stain, dysplasia or hyperplasia, malignancy and reactive changes in the epithelium were evaluated.

RESULTS

The study was conducted with 86 patients aged between two and 35, of whom 32 were women (37.2%) and 54 were men (62.8%). The mean age of cases was 8.37 ± 5.95. The mean difference between two tonsils ranged from 1 to 12 mm, mean 3.67 ± 2.56 mm. When the findings were examined, the presence of H. pylori, Coccobacillus, fungus and Actinomyces, reactive changes in the epithelium, pattern of hyperplasia, intraepithelial abscess and macroscopic presence of pus did not reveal any statistically significant changes.

CONCLUSION

The reasons behind asymmetric tonsil hypertrophies and how they are related to malignancies have not yet been clarified. There is no statistically significant difference between the evaluated parameters in the present study. This study has brought a new point of view to the subject by comparing different-sized tonsils in the same person, thus paving the way for future studies with a broader scope.

Phenotypic and Physiological Characterization of the Epibiotic Interaction Between TM7x and Its Basibiont Actinomyces

Despite many examples of obligate epibiotic symbiosis (one organism living on the surface of another) in nature, such an interaction has rarely been observed between two bacteria. Here, we further characterize a newly reported interaction between a human oral obligate parasitic bacterium TM7x (cultivated member of Candidatus Saccharimonas formerly Candidate Phylum TM7), and its basibiont Actinomyces odontolyticus species (XH001), providing a model system to study epiparasitic symbiosis in the domain Bacteria. Detailed microscopic studies indicate that both partners display extensive morphological changes during symbiotic growth. XH001 cells manifested as short rods in monoculture, but displayed elongated and hyphal morphology when physically associated with TM7x. Interestingly, these dramatic morphological changes in XH001 were also induced in oxygen-depleted conditions, even in the absence of TM7x. Targeted quantitative real-time PCR (qRT-PCR) analyses revealed that both the physical association with TM7x as well as oxygen depletion triggered up-regulation of key stress response genes in XH001, and in combination, these conditions act in an additive manner. TM7x and XH001 co-exist with relatively uniform cell morphologies under nutrient-replete conditions. However, upon nutrient depletion, TM7x-associated XH001 displayed a variety of cell morphologies, including swollen cell body, clubbed-ends, and even cell lysis, and a large portion of TM7x cells transformed from ultrasmall cocci into elongated cells. Our study demonstrates a highly dynamic interaction between epibiont TM7x and its basibiont XH001 in response to physical association or environmental cues such as oxygen level and nutritional status, as reflected by their morphological and physiological changes during symbiotic growth.

[Isolation and identification of aerobic and facultative anaerobic bacteria in the oral cavity]

OBJECTIVE

To establish a systematic method for isolation and identification of aerobic and facultative anaerobic bacteria in the oral cavity.

METHODS

Samples of the saliva, dental plaque and periapical granulation tissue were collected from 20 subjects with healthy oral condition and from 8 patients with different oral diseases. The bacteria in the samples were identified by morphological identification, VITEK automatic microorganism identification and 16s rRNA gene sequencing.

RESULTS

VITEK automatic microorganism identification and 16s rRNA gene sequencing showed an agreement rate of 22.39% in identifying the bacteria in the samples. We identified altogether 63 bacterial genus (175 species), among which Streptococcus, Actinomyces and Staphylococcus were the most common bacterial genus, and Streptococcus anginosus, Actinomyces oris, Streptococcus mutans and Streptococcus mitis were the most common species. Streptococcus anginosus was commonly found in patients with chronic periapical periodontitis. Streptococcus intermedius and Staphylococcus aureus were common in patients with radiation caries, and in patients with rampant caries, Streptococcus mutans was found at considerably higher rate than other species.

CONCLUSION

Aerobic and facultative anaerobic bacteria are commonly found in the oral cavity, and most of them are gram-positive. 16s rRNA gene sequencing is more accurate than VITEK automatic microorganism identification in identifying the bacteria.

Analysis of the Microbiota of Black Stain in the Primary Dentition

Black tooth stain is a characteristic extrinsic discoloration commonly seen on the cervical enamel following the contour of the gingiva. To investigate the relationship between black tooth stain and the oral microbiota, we used 16S rRNA gene sequencing to compare the microbial composition of dental plaque and saliva among caries-free children with and without black stain. Dental plaque and saliva, as well as black stain, were sampled from 10 children with and 15 children without black stain. Data were analyzed using the pipeline tool MOTHUR. Student’s t-test was used to compare alpha diversities and the Mann-Whitney U test to compare the relative abundances of the microbial taxa. A total of 10 phyla, 19 classes, 32 orders, 61 families and 102 genera were detected in these samples. Shannon and Simpson diversity were found to be significantly lower in saliva samples of children with black stain. Microbial diversity was reduced in the black stain compared to the plaque samples. Actinomyces, Cardiobacterium, Haemophilus, Corynebacterium, Tannerella and Treponema were more abundant and Campylobacter less abundant in plaque samples of children with black stain. Principal component analysis demonstrated clustering among the dental plaque samples from the control group, while the plaque samples from the black stain group were not and appeared to cluster into two subgroups. Alterations in oral microbiota may be associated with the formation of black stain.

Acne inversa complicated by Actinomyces neuii

INTRODUCTION

Acne inversa (AI) is a chronic and recurrent inflammatory skin disease. It occurs in intertriginous areas of the skin and causes pain, drainage, malodor and scar formation. While supposedly caused by an autoimmune reaction, bacterial superinfection is a secondary event in the disease process.

METHODS

A unique case of a 43-year-old male patient suffering from a recurring AI lesion in the left axilla was retrospectively analysed.

RESULTS

A swab revealed Actinomyces neuii as the only agent growing in the lesion. The patient was then treated with Amoxicillin/Clavulanic Acid 3 × 1 g until he was cleared for surgical excision. The intraoperative swab was negative for A. neuii. Antibiotics were prescribed for another 4 weeks and the patient has remained relapse free for more than 12 months now.

CONCLUSION

Primary cutaneous Actinomycosis is a rare entity and the combination of AI and Actinomycosis has never been reported before. Failure to detect superinfections of AI lesions with slow-growing pathogens like Actinomyces spp. might contribute to high recurrence rates after immunosuppressive therapy of AI. The present case underlines the potentially multifactorial pathogenesis of the disease and the importance of considering and treating potential infections before initiating immunosuppressive regimens for AI patients.

Periodontal Bacteria and Prediabetes Prevalence in ORIGINS: The Oral Infections, Glucose Intolerance, and Insulin Resistance Study

Periodontitis and type 2 diabetes mellitus are known to be associated. The relationship between periodontal microbiota and early diabetes risk has not been studied. We investigated the association between periodontal bacteria and prediabetes prevalence among diabetes-free adults. ORIGINS (the Oral Infections, Glucose Intolerance and Insulin Resistance Study) cross sectionally enrolled 300 diabetes-free adults aged 20 to 55 y (mean ± SD, 34 ± 10 y; 77% female). Prediabetes was defined as follows: 1) hemoglobin A1c values ranging from 5.7% to 6.4% or 2) fasting plasma glucose ranging from 100 to 125 mg/dL. In 1,188 subgingival plaque samples, 11 bacterial species were assessed at baseline, including Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Actinomyces naeslundii. Full-mouth clinical periodontal examinations were performed, and participants were defined as having no/mild periodontitis vs. moderate/severe periodontitis per the definition of the Centers for Disease Control and Prevention / American Academy of Periodontology. Modified Poisson regression evaluated prediabetes prevalence across bacterial tertiles. Prevalence ratios and 95% confidence intervals for third vs. first tertiles are presented. All analyses were adjusted for cardiometabolic risk factors. All results presented currently arise from the baseline cross section. Prediabetes prevalence was 18%, and 58% of participants had moderate/severe periodontitis. Prevalence ratios (95% confidence intervals) summarizing associations between bacterial levels and prediabetes were as follows: A. actinomycetemcomitans, 2.48 (1.34, 4.58), P = 0.004; P. gingivalis, 3.41 (1.78, 6.58), P = 0.0003; T. denticola, 1.99 (0.992, 4.00), P = 0.052; T. forsythia, 1.95 (1.0, 3.84), P = 0.05; A. naeslundii, 0.46 (0.25, 0.85), P = 0.01. The prevalence ratio for prediabetes among participants with moderate/severe vs. no/mild periodontitis was 1.47 (0.78, 2.74), P = 0.23. Higher colonization levels of specific periodontal microbiota are associated with higher prediabetes prevalence among diabetes-free adults.

Can oral anaerobic bacteria cause adverse pregnancy outcomes?

AIM

Maternal periodontal infection has been recognized as a risk factor for premature and low birthweight infants. It is suspected that pathogens causing periodontal disease may translocate to the amniotic cavity and so contribute to triggering an adverse pregnancy outcome. The aim of this study was to evaluate whether the presence of specific periodontal pathogens may influence the incidence of preterm labor and premature birth.

MATERIAL AND METHODS

This study was designed as a hospital-based case-control study. A total of 70 pregnant women, aged 18-40 with single live pregnancy were recruited from the Departement of Gynecolgy and Obstetrics at a General hospital in Sibenik, Croatia, between March 2013 to March 2014. The case group: 30 pregnant women who were hospitalised with signs of premature labor.

CONTROL GROUP

40 patients with normal pregnancy post-delivery up to 48 hrs, who had given birth at term, and the baby had a weight of more than 2500 gr. These women had undergone microbiological examination at the time of recruitment, microbial samples, paper point subgingival swabs were obtained in both groups and processed by anaerobic culturing. Standard procedures were used for culture and identification of bacteria. Information was collected on demographics, health behaviors, and obstetric and systemic diseases that may have influence the premature delivery.

RESULTS

The levels of periodontal pathogens tended to be higher in the premature (case group) labor compared to the term deliveries (control group). Levels of Porphyromonas gingivalis, Fuscobacterium nucleatum, Actinomyces actinomycetecomitans were statistically significantly higher in premature births as compared to term deliveries, adjusting for baseline levels. The joint effects of red and orange microbial clusters were significantly higher in the premature group compared to the term group.

CONCLUSIONS

The study shows a significant association betwen periodontal anaerobic infection and adverse pregnancy outcome. High levels of periodontal pathogens during pregnancy are associated with an increased risk for preterm delivery. Further studies elucidating the role of the microbial load and maternal immune response as related to pregnancy outcome seem merited.

Actinomyces turicensis Bacteremia Secondary to Pyometra

We herein present a rare case of Actinomyces turicensis bacteremia that was caused by pyometra. The patient was successfully treated with transvaginal drainage and antibiotic therapy. A literature review in MEDLINE showed that there have been only 8 previously reported cases of A. turicensis bacteremia. This infection frequently occurs in patients with visceral abscesses, and blood culture examinations usually reveal a polymicrobial pattern. However, the prognosis of such patients has been reported to generally be benign. Due to difficulties in performing bacterial identification and the wide-spectrum clinical pictures associated with this bacteremia, no comprehensive understanding of the clinical features of each Actinomyces species has yet been established.

Actinomycotic sinus of the buccal mucosa: a rare complication of cheek dimple creation

Even though actinomyces are common oral commensals, actinomycosis is an uncommon oral infection. Cheek dimple creation is a common surgical procedure with rare complications. Bacterial infection with abscess formation and foreign body reaction were reported. We report a rare example-and, to our knowledge, the first-of oral actinomycosis after cheek dimple creation. A young woman complained of a chronic tender nodule of the right buccal mucosa with pus discharge after surgery for cheek dimple creation. Histologic examination showed a sinus tract with actinomyces microorganisms. This complication can be mimicked by other oral or dental sinus-forming lesions, can be chronic and insidious, and could therefore clinically be missed or mistreated. This might delay the diagnosis and cause scarring and disfigurement. The treatment of choice is early recognition and complete surgical excision to avoid irreversible complications and prevent recurrence. Awareness of this potential complication by aesthetic surgeons, oral clinicians, and dentists is important. Patients' adherence to preventive measures and plastic surgeons' application of inclusion criteria and contraindications, as well as their choice of best technique per patient, should help minimize such a problem in a simple and safe aesthetic procedure. LEVEL OF EVIDENCE 5:

Paediatric ventriculoperitoneal shunt infection caused by Actinomyces neuii

We present the first reported case of ventriculoperitoneal shunt infection secondary to Actinomyces neuii in a paediatric patient. Our patient was managed with temporary shunt removal, intrathecal antibiotics and a prolonged course of intravenous and then oral antibiotics. She went on to make a complete recovery. Subsequent cerebrospinal fluid analysis at 5 months post-treatment demonstrated no evidence of residual infection.

Abdominal actinomycosis: a rare complication after cholecystectomy

We present a single case of abdominal actinomycosis occurring in a 74-year-old female with a history of cholecystectomy 42 months before presentation. In a review of the literature, we present risk factors, clinical characteristics, diagnosis, and treatment of this infection. Abdominal actinomycosis is a rare, chronic, granulomatous infection characterized by the release of 'sulphur granules'. Actinomyces species should always be part of the differential diagnosis of patients presenting with a history of surgical or invasive procedures, presenting with an abdominal mass. Computed tomography (CT)-guided aspiration with or without core biopsy of this mass is a useful investigation. Diagnosis is often difficult: In less than 10% of cases, the diagnosis is made pre-operatively. Definitive diagnosis is often based on histochemical, macroscopic, and microscopic examination of tissue specimens. The disease should be treated with high doses of intravenous penicillin for 2-6 weeks followed by oral therapy for at least 6-12 months.

Actinomyces meyeri meningitis: the need for anaerobic cerebrospinal fluid cultures

We herein present a rare case of Actinomyces meyeri-induced meningitis that occurred in a patient of advanced age with poor oral hygiene. Although Gram staining of the cerebrospinal fluid (CSF) revealed Gram-positive rods and a blood culture was positive for the organism, a bacterial culture of the CSF was negative. Anaerobic cultures of CSF specimens are not routinely performed; however, anaerobes are sometimes involved in central nervous system infection. We therefore believe that anaerobic cultures should be considered in high-risk cases, such as those involving necrotizing bowel lesions or poor oral hygiene. A negative result on a CSF culture can result in misdiagnosis and inappropriate treatment.

[Rare infection--prolonged A. naeslundii bacteremia caused by severe caries]

Actinomyces is an anaerobic, gram positive, rod shape bacteria that doesn't create spores. Actinomyces is part of the mouth, intestines, vagina and upper respiratory system flora. The infection appears mostly on the face, neck, abdomen and pelvis in cases of mucosa injury and most common in immunosuppressed patients. The spread of Actinomyces through the blood system is rare. In this article we present a 9 year old male patient with no history of diseases who was diagnosed with prolonged bacteremia of A. naeslundii without specific infection excluding severe caries. Characterization of bacteria from the blood culture was performed by molecular biology and the patient was treated with Ampicillin and tooth extraction that led to the disappearance of the bacteremia.

Identification of coryneform Actinomyces neuii by MALDI-TOF MS: 5 case reports and review of literature

OBJECTIVES

We describe five cases of Actinomyces neuii, isolated from different clinical specimens over a period of five months (from June to October 2011), followed by a review of literature on infections with this micro-organism.

METHODS

All Actinomyces neuii strains were cultured or subcultured on horse blood agar. Identification took place using matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS). Identification was confirmed by conventional biochemical tests and API Coryne test strips (BioMérieux SA). Susceptibility testing was performed on Mueller-Hinton agar supplemented with horse blood, using E-tests (BioMérieux SA). The minimal inhibitory concentrations were determined after 24 and 48 hours of incubation in a 5% CO2 environment.

RESULTS

Isolation of this micro-organism was associated with abscesses in two patients and chronic osteomyelitis in one patient. The remaining two patients had positive blood cultures which grew Actinomyces neuii, either as contamination or as catheter-related infection. All Actinomyces neuii identifications were obtained by MALDI-TOF MS and were confirmed by conventional biochemical and API Coryne tests. Identification of one isolate was also confirmed by 16S rRNA sequencing. All strains were susceptible to penicillin. One strain showed heteroresistance for macrolides and lincosamides. Minimal inhibitory concentrations were more reliable and easier to read after 48 hours of incubation, as compared to 24 hours.

CONCLUSION

MALDI-TOF MS analysis allows rapid and reliable identification of Actinomyces neuii, even at subspecies level.