Microbiology and management of joint and bone infections due to anaerobic bacteria

Osteomyelitis of a long bone due to Fusobacterium nucleatum and Actinomyces meyeri in an immunocompetent adult: a case report and literature review

Background

Fusobacterium species are uncommon causes of osteomyelitis. These organisms are normal flora of the oral cavity. Therefore, they mostly cause osteomyelitis of the head and neck. Hematogenous osteomyelitis at distant sites other than the head and neck has rarely been reported in pediatric or immunocompromised patients. Here, we report the first case of osteomyelitis of a long bone combined with a muscle abscess due to Fusobacterium nucleatum in an otherwise healthy adult.

Case presentation

A 59-year-old Korean man was admitted for pain and swelling of the right lower leg, which had been persistent for two weeks. Magnetic resonance imaging showed osteomyelitis of the right fibula with a surrounding muscle abscess of the right lower leg. Incision and drainage was performed, and repetitive tissue cultures grew F. nucleatum. In this patient, it was presumed that recurrent periodontitis caused hematogenous seeding of F. nucleatum to a distant site leading to osteomyelitis with a muscle abscess. The patient was successfully treated with intravenous ampicillin-sulbactam for three weeks and oral amoxicillin-clavulanate for eight weeks. He also underwent repeated surgical drainage. He has no evidence of recurrence after seven months of follow-up.

Conclusions

Clinicians should be aware that F. nucleatum could be the etiologic agent of hematogenous osteomyelitis of a long bone in an immunocompetent patient.

Microbiota associated with infections of the jaws

The microbial infections involving the craniofacial skeleton, particularly maxilla and mandible, have direct relationship with the dental biofilm, with predominance of obligate anaerobes. In some patients, these infections may spread to bone marrow or facial soft tissues, producing severe and life-threatening septic conditions. In such cases, local treatment associated with systemic antimicrobials should be used in order to eradicate the sources of contamination. This paper discuss the possibility of spread of these infections and their clinical implications for dentistry, as well as their etiology and aspects related to microbial virulence and pathogenesis.

Septic arthritis and osteomyelitis in a 10-year-old boy, caused by Fusobacterium nucleatum, diagnosed with PCR/16S ribosomal bacterial DNA amplification

A 10-year-old boy presented with an atypical non-febrile septic arthritis/osteomyelitis. He was unresponsive to routine antibiotic treatment with flucloxacillin/gentamicin as the pain and fluid collection increased. Synovial fluid cultures are negative and gram stain remained negative. Only after PCR/16S ribosomal bacterial DNA amplification a Fusobacterium nucleatum could be detected, and antibiotic therapy switched to clindamycin with rapid response. Septic osteomyelitis and arthritis are relatively rare but important infections in children needing prompt treatment, and should be considered when a child complaints about joint or bone pain without prior recent trauma. Skin bacteria are the most prevalent causative organisms, whereas Fusobacteria or other anaerobic, Gram-negative microorganisms are very seldom encountered. If cultures remain negative and the patients responds insufficiently to empiric treatment, PCR/16S ribosomal bacterial DNA amplification can be useful to detect the causative microorganisms.

Hot melt poly-ε-caprolactone/poloxamine implantable matrices for sustained delivery of ciprofloxacin

It has been suggested that prevention and treatment of osteomyelitis could be achieved through local drug delivery using implantable devices, which provide therapeutic levels at the infection site with minimum side-effects. Physical blends of polycaprolactone (PCL) and poloxamine (Tetronic®) were prepared by applying a solvent-free hot melting approach to obtain cytocompatible implants with a tunable bioerosion rate, ciprofloxacin release profile and osteoconductive features. Differential scanning calorimetry and X-ray analysis indicate that the hydrophilic poloxamine varieties T908, T1107, and T1307 are miscible with PCL, while the hydrophobic block copolymer T1301 is immiscible. Incorporation of the block copolymer at weight ratios ranging from 25 to 75 wt.% led to matrices with viscoelastic parameters in the range of those of fresh cortical bone. Once immersed in buffer the matrices underwent a similar weight loss in the first week to the content of poloxamine, followed by a slower erosion rate due to PCL. The initial rapid erosion and the increase in porosity partially explain the observed burst of ciprofloxacin release, which is more intense in the PCL:T1301 formulation due to drug/T1301 repulsion due to polarity. The matrices sustained ciprofloxacin release for several months (<50% released after 3 months) and showed in vitro efficacy against Staphylococcus aureus, eradicating the bacteria in less than 48 h. PCL:poloxamine was cytocompatible with osteoblasts and the matrices prepared with low proportions of T908 were also compatible with mesenchymal stem cell differentiation to osteoblasts. The influence of the nature and proportion of temperature-responsive poloxamine on the performance of PCL implantable systems was determined.

Successful salvage therapy with Daptomycin for osteomyelitis caused by methicillin-resistant Staphylococcus aureus in a renal transplant recipient with Fabry-Anderson disease

Daptomycin is licensed in adults for the management of Staphylococcus aureus methicillin-resistant infections, including bone and skin complicated infections. We describe for the first time its use in a renal transplant recipient for Fabry-Anderson Disease with right heel osteomyelitis. The patient was unresponsive to first-line Teicoplanin and second-line Tigecycline, whereas he was successfully treated with third-line Daptomycin monotherapy at 4 mg/Kg/qd for 4 weeks. Local debridement was performed in advance of each line of treatment.

Investigation of Propionibacterium acnes in progressive macular hypomelanosis using real-time PCR and culture

BACKGROUND

Progressive macular hypomelanosis (PMH) is a dermatosis of unknown etiology. It has been concluded that it involves the presence of Propionibacterium acnes, a saprophyte of the pilosebaceous follicles. In our study, we investigated the presence of P. acnes in lesional and non-lesional skin of patients with PMH through quantitative real-time polymerase chain reaction (PCR) and bacterial culture from a skin fragment.

MATERIALS AND METHODS

An observational, exploratory study, with laboratory comparison of lesional (study group) and non-lesional skin (comparison group), in patients with PMH, was carried out with 36 patients, seen in the dermatology outpatient setting at the Oswaldo Cruz University Hospital (OCUH), Recife, Pernambuco, Brazil, between March and May 2008. All patients were submitted to a Wood's lamp examination, mycological research, and biopsies of lesional and non-lesional skin from the back. Skin fragments were submitted to a histopathology test, bacterial culture, and a quantitative real-time PCR test. The program Statistical Package for Social Sciences, version 12.0, was employed for relationship analysis with the Wilcoxon and McNemar tests.

RESULTS

There was a significant predominance of P. acnes on lesional skin, in comparison to non-lesional skin (P<0.001), as demonstrated by culture and quantitative real-time PCR.

CONCLUSION

Although P. acnes is a saprophyte, the hypothesis may be raised that this microorganism participates in the development of PMH.

Extensive, non-healing scalp ulcer associated with trauma-induced chronic osteomyelitis

A 77-year-old woman presented with a trauma to the scalp caused from the blade of a windmill. The condition was persistent from the past 50 years. At the initial examination, a deep, foul-smelling and well-circumscribed ulcer was apparent on the head region, involving the majority of the cranium. Skin biopsy specimens of the lesion were nonspecific. The bone biopsy showed extensive necrotic areas of bone and soft tissues, with lymphocytic exudate foci. A computed tomography scan of the head revealed bone destruction principally involving both the parietal bones, and parts of the frontal and occipital bones. Streptococcus parasanguis was isolated from the skin culture, and Proteus mirabilis and Peptostreptococcus sp. were identified in the cultures from the bone. A long-term treatment with amoxicillin-clavulanic acid (1 g/12 h) and levofloxacin (500 mg/day) was prescribed, but even after 6 months, the lesion remained unchanged. The frequency of occurrence of scalp ulcers in dermatological patients is less, principally because of the rich blood supply to this area. We have not found any similar case report of a scalp ulcer secondary to chronic osteomyelitis discovered more than 50 years after the causal trauma. We want to highlight the importance of complete cutaneous evaluation including skin and bone biopsies, when scalp osteomyelitis is suspected.

Pyomyositis and septic hip arthritis due to bacteroides fragilis. A case report

Bacteroides fragilis is a rare cause of pyomyositis or septic arthritis. We present the case of a 74-year-old otherwise healthy male who presented with fever and right hip pain ten days after a course of intramuscular injections. Magnetic resonance imaging (MRI) showed septic arthritis of the right hip joint and pyomyositis of the right gluteus minimus muscle. Blood cultures and pus aspirated from the muscle grew Bacteroides fragilis. The patient was treated successfully with surgical debridement and metronidazole, administered for six weeks intravenously and five weeks orally. Simultaneous pyomyositis and hip septic arthritis due to Bacteroides fragilis is rare, but should be considered possible after intramuscular injections.

Fusobacterium nucleatum prosthetic hip infection in an adult with sickle cell-beta thalassemia

Fusobacterium nucleatum is an anaerobic Gram-negative bacillus commensal to the human oropharynx and gastrointestinal tract which causes an array of human infection, yet it has never been associated with infection of prosthetic joints. We report the first case of prosthetic hip infection caused by F. nucleatum in a man with sickle cell-beta thalassemia.

Emerging roles of pathogens in Alzheimer disease

Chronic spirochetal infection can cause slowly progressive dementia, cortical atrophy and amyloid deposition in the atrophic form of general paresis. There is a significant association between Alzheimer disease (AD) and various types of spirochete (including the periodontal pathogen Treponemas and Borrelia burgdorferi), and other pathogens such as Chlamydophyla pneumoniae and herpes simplex virus type-1 (HSV-1). Exposure of mammalian neuronal and glial cells and organotypic cultures to spirochetes reproduces the biological and pathological hallmarks of AD. Senile-plaque-like beta amyloid (Aβ) deposits are also observed in mice following inhalation of C. pneumoniae in vivo, and Aβ accumulation and phosphorylation of tau is induced in neurons by HSV-1 in vitro and in vivo. Specific bacterial ligands, and bacterial and viral DNA and RNA all increase the expression of proinflammatory molecules, which activates the innate and adaptive immune systems. Evasion of pathogens from destruction by the host immune reactions leads to persistent infection, chronic inflammation, neuronal destruction and Aβ deposition. Aβ has been shown to be a pore-forming antimicrobial peptide, indicating that Aβ accumulation might be a response to infection. Global attention and action is needed to support this emerging field of research because dementia might be prevented by combined antibiotic, antiviral and anti-inflammatory therapy.

Granulomatous Propionibacterium acnes infection after trauma surgery

We report here a rare case of infection caused by Propionibacterium acnes following trauma surgery: a 36-year-old male, accident victim was admitted to the hospital because of polytrauma. He underwent a long-drawn-out surgical intervention and after a free-muscle transfer using the rectus femoris muscle, signs of inflammation were detected in the affected area. Microbiological examination of the wound revealed the presence of P. acnes as the only etiological agent of this infection. Adequate antibiotic treatment with penicillin had been started right after the positive microbiological result. Our data confirm the pathogenic potential of P. acnes in late post-surgical infections, and suggest a proper therapeutic approach with intravenous antibiotics and surgical removal of the infected tissue.

Rapid label-free identification of mixed bacterial infections by surface plasmon resonance

Background

Early detection of mixed aerobic-anaerobic infection has been a challenge in clinical practice due to the phenotypic changes in complex environments. Surface plasmon resonance (SPR) biosensor is widely used to detect DNA-DNA interaction and offers a sensitive and label-free approach in DNA research.

Methods

In this study, we developed a single-stranded DNA (ssDNA) amplification technique and modified the traditional SPR detection system for rapid and simultaneous detection of mixed infections of four pathogenic microorganisms (Pseudomonas aeruginosa, Staphylococcus aureus, Clostridium tetani and Clostridium perfringens).

Results

We constructed the circulation detection well to increase the sensitivity and the tandem probe arrays to reduce the non-specific hybridization. The use of 16S rDNA universal primers ensured the amplification of four target nucleic acid sequences simultaneously, and further electrophoresis and sequencing confirmed the high efficiency of this amplification method. No significant signals were detected during the single-base mismatch or non-specific probe hybridization (P < 0.05). The calibration curves of amplification products of four bacteria had good linearity from 0.1 nM to 100 nM, with all R² values of >0.99. The lowest detection limits were 0.03 nM for P. aeruginosa, 0.02 nM for S. aureus, 0.01 nM for C. tetani and 0.02 nM for C. perfringens. The SPR biosensor had the same detection rate as the traditional culture method (P < 0.05). In addition, the quantification of PCR products can be completed within 15 min, and excellent regeneration greatly reduces the cost for detection.

Conclusions

Our method can rapidly and accurately identify the mixed aerobic-anaerobic infection, providing a reliable alternative to bacterial culture for rapid bacteria detection.

Atypical osteomyelitis of the skull base and craniovertebral junction caused by Actinomyces infection--case report

A 44-year-old man presented with a very rare case of skull base osteomyelitis manifesting as persistent diplopia. He initially had the symptom with fever after dental extraction. Biopsy from the cervix and upper pharynx performed in a previous hospital had showed negative findings by histological and bacterial examinations. Magnetic resonance (MR) imaging disclosed enhanced lesions in the right cavernous sinus, clivus, and right cervical regions. Computed tomography revealed osteolysis, and fluorodeoxyglucose positron emission tomography (FDG-PET) showed areas of increased uptake. Bacteriological examination of the isolated clival lesion disclosed Actinomyces israelii, and he was treated with intravenous penicillin, 18 million units a day for 6 weeks. MR imaging revealed reduction of intensity in the enhanced areas, and FDG-PET showed disappearance of the increased uptake. After 6 months of oral antibiotics administration, MR imaging disclosed disappearance of the enhanced lesions, and the patient had no sign of neurological deficits. Skull base osteomyelitis resembles neoplasm or inflammatory disease of this region in neurological and radiographic findings. The biopsy specimen should be ideally obtained from an isolated region, and prepared to identify a wide range of organisms and to differentiate other diseases. The serum level of C-reactive protein and FDG-PET are useful to follow up the efficacy of antibiotic therapy.

New insights into Prevotella diversity and medical microbiology

In light of recent studies based on cultivation-independent methods, it appears that the diversity of Prevotella in human microbiota is greater than was previously assumed from cultivation-based studies, and that the implication of these bacteria in several human diseases was unrecognized. While some Prevotella taxa were found during opportunistic infections, changes in Prevotella abundance and diversity were discovered during dysbiosis-associated diseases. As member of the microbiota, Prevotella may also be considered as a reservoir for resistance genes. Greater knowledge on Prevotella diversity, as well as new insights into its pathogenic potential and implication in dysbiosis are expected from the use of human microbe identification microarrays, from whole-genome sequence analyse, and from the NIH Human Microbiome Project data. New approaches, including molecular-based methods, could contribute to improve the diagnosis of Prevotella infections.

Surgical treatment of osteomyelitis and formation of a sequestrum in the distal metaphysis of the humerus in an alpaca cria

CASE HISTORY

An 8-week-old, 16-kg alpaca cria was presented with a 2-week history of acute onset of left forelimb lameness.

CLINICAL FINDINGS

The cria was weight-bearing but lame at the walk in the left forelimb. There was swelling, heat and pain on palpation of the soft tissues, extending from the mid-shaft of the humerus to the elbow. There was no evidence of a traumatic injury. Radiologically, there was evidence of osteomyelitis and a sequestrum involving the distal metaphysis of the humerus. The sequestrum was removed surgically. No bacteria were cultured from samples taken during surgery. After an initial improvement, the cria became acutely lame, and developed an abscess at the surgical site, which was drained. A pure growth of a strictly anaerobic, Gram-negative, non-spore-forming, pleomorphic, filamentous rod was cultured from fluid from the abscess. Further radiographs suggested a second sequestrum was present, and this was removed surgically. Apart from partial dehiscence of the wound, the cria recovered well, and was sound and without complications 18 months after surgery.

DIAGNOSIS

Osteomyelitis and formation of sequestra in the distal metaphysic of the left humerus.

CLINICAL RELEVANCE

There has only been one case of osteomyelitis and bone sequestration without evidence of trauma in alpaca crias reported in the literature. However, anecdotal reports by veterinary practitioners described similar cases of osteomyelitis and bone sequestration, usually affecting the long bones. Further investigation of osteomyelitis and bone sequestration in crias is needed, to define the incidence, determine the pathogenesis, and develop specific recommendations for prevention and treatment.

Microbiota associated with chronic osteomyelitis of the jaws

Chronic osteomyelitis of maxilla and mandible is rare in industrialized countries and its occurrence in developing countries is associated with trauma and surgery, and its microbial etiology has not been studied thoroughly. The aim of this investigation was to evaluate the microbiota associated with osteomyelitis of mandible or maxilla from some Brazilian patients. After clinical and radiographic evaluation, samples of bone sequestra, purulent secretion, and biopsies of granulomatous tissues from twenty-two patients with chronic osteomyelitis of mandible and maxilla were cultivated and submitted for pathogen detection by using a PCR method. Each patient harbored a single lesion. Bacterial isolation was performed on fastidious anaerobe agar supplemented with hemin, menadione and horse blood for anaerobes; and on tryptic soy agar supplemented with yeast extract and horse blood for facultative bacteria and aerobes. Plates were incubated in anaerobiosis and aerobiosis, at 37(o)C for 14 and 3 days, respectively. Bacteria were cultivated from twelve patient samples; and genera Actinomyces, Fusobacterium, Parvimonas, and Staphylococcus were the most frequent. By PCR, bacterial DNA was detected from sixteen patient samples. The results suggest that cases of chronic osteomyelitis of the jaws are usually mixed anaerobic infections, reinforcing the concept that osteomyelitis of the jaws are mainly related to microorganisms from the oral environment, and periapical and periodontal infections may act as predisposing factors.

Surgical treatment of osteomyelitis and sequestration of the ilium by a cranial partial hemipelvectomy in an alpaca cria

A 12-week-old female alpaca cria weighing 10 kg presented with a 2-month history of left hindlimb lameness associated with osteomyelitis and sequestration of the shaft and wing of the left ilium. The affected segment of the ilium was surgically removed. Bacteriological culture revealed a small number of mixed aerobic and anaerobic bacteria. The cria recovered well, was discharged from the hospital 8 days after surgery and was paddock sound without complications 8 months later. Osteomyelitis and sequestration of long bones has been reported in alpacas, but further investigation is necessary to define the prevalence and pathogenesis and to develop specific recommendations for prevention and treatment.

Quantitative detection of periodontopathic bacteria in atherosclerotic plaques from coronary arteries

Oral pathogens, including periodontopathic bacteria, are thought to be aetiological factors in the development of cardiovascular disease. In this study, the presence of Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum-periodonticum-simiae group, Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens and Tannerella forsythia in atheromatous plaques from coronary arteries was determined by real-time PCR. Forty-four patients displaying cardiovascular disease were submitted to periodontal examination and endarterectomy of coronary arteries. Approximately 60-100 mg atherosclerotic tissue was removed surgically and DNA was obtained. Quantitative detection of periodontopathic bacteria was performed using universal and species-specific TaqMan probe/primer sets. Total bacterial and periodontopathic bacterial DNA were found in 94.9 and 92.3 %, respectively, of the atheromatous plaques from periodontitis patients, and in 80.0 and 20.0 %, respectively, of atherosclerotic tissues from periodontally healthy subjects. All periodontal bacteria except for the F. nucleatum-periodonticum-simiae group were detected, and their DNA represented 47.3 % of the total bacterial DNA obtained from periodontitis patients. Porphyromonas gingivalis, A. actinomycetemcomitans and Prevotella intermedia were detected most often. The presence of two or more periodontal species could be observed in 64.1 % of the samples. In addition, even in samples in which a single periodontal species was detected, additional unidentified microbial DNA could be observed. The significant number of periodontopathic bacterial DNA species in atherosclerotic tissue samples from patients with periodontitis suggests that the presence of these micro-organisms in coronary lesions is not coincidental and that they may in fact contribute to the development of vascular diseases.