Cause Of Osteomyelitis Research Articles

Suppurative Granulomatous Osteomyelitis with Microcystic Changes Due to Mycobacterium chelonae- abscessus Complex

Abstract Introduction/Objective Mycobacterium chelonae and Mycobacterium abscessus are rapidly growing non-tuberculous mycobacterium found in soil and water, and represent rare causes of skin and soft tissue infection. Treatment typically involves an extended course of antimicrobial therapy and occasionally surgical debridement. Previous reports have described a distinctive pattern of suppurative granulomatous inflammation with microcystic changes in skin biopsies; however, the morphologic changes of M. chelonae-abscessus complex as a cause of osteomyelitis have not been well-documented in the literature. Methods/Case Report We searched our database from 2013 to 2024 for bone samples diagnosed as granulomatous inflammation in which M. chelonae or M. abscessus were identified on concurrent microbiology studies. Patient demographics, risk factors for infection, and treatment data were collected. Results (if a Case Study enter NA) Three patients with culture- or PCR-confirmed M. chelonae (2) or M. abscessus (1) were identified. All infections involved bones of the distal extremities. Patients were 57 years and older with risk factors for infection that included: diabetes (1), intravenous drug use (1), and long-term immunosuppressive therapy (1). All patients presented with osteomyelitis refractory to antibiotic therapy for which bone biopsy, bone resection, or amputation was performed. All cases showed suppurative granulomatous inflammation with microcystic changes. Cystic spaces were markedly enriched for acid-fast bacilli on Fite and/or Ziehl-Neelsen stains. In two patients, the antimicrobial regimen was changed as a result of the pathologic findings and microbiologic testing that provided additional information about speciation and susceptibilities. Conclusion Suppurative granulomatous inflammation has a broad differential that includes blastomycosis, sporotrichosis, cat scratch disease, non-tuberculous mycobacterial infection, and granulomatosis with polyangiitis, for which there are substantial treatment differences. When this pattern of microcystic suppurative granulomatous inflammation is encountered, it is important to perform special stains for acid-fast bacilli, particularly when seen in distal extremity lesions from patients with infections that are refractory to empiric antibiotic therapy.

Chronic otorrhea and osteomyelitis of the external auditory canal by Achromobacter xylosoxidans: an uncommon diagnosis

PurposeAchromobacter xylosoxidans is an emerging pathogen mainly associated with resistant nosocomial infections. This bacteria had been isolated in the ear together with other pathogens in cultures from patients with chronic otitis media, but it had never been reported as a cause of osteomyelitis of the external auditory canal.Case presentationWe present a unique case of a healthy 81-year-old woman who presented with left chronic otorrhea refractory to topical and oral antibiotic treatment. Otomicroscopy revealed an erythematous and exudative external auditory canal (EAC) with scant otorrhea. The tympanic membrane was intact, but an area of bone remodeling with a small cavity anterior and inferior to the bony tympanic frame was observed. Otic culture isolated multi-drug-resistant A. xylosoxidans, only sensitive to meropenem and cotrimoxazole. Temporal bone computed tomography showed an excavation of the floor of the EAC compatible with osteomyelitis. Targeted antibiotherapy for 12 weeks was conducted, with subsequent resolution of symptoms and no progression of the bone erosion.ConclusionsAtypical pathogens such as A. xylosoxidans can be the cause of chronic otitis externa. Early diagnosis and specific antibiotherapy can prevent the development of further complications, such as osteomyelitis. In these cases, otic cultures play an essential role to identify the causal germ. This is the first case of EAC osteomyelitis due to A. xylosoxidans reported to date.

Culture-Negative Osteomyelitis: Is it Haemophilus haemolyticus?

Case: A 50-year-old woman presented to our emergency department with severe intractable atraumatic right hip pain. She was admitted to the hospital, and an orthopaedic consult was requested. She does have a known history of right hip osteoarthritis, but does not actively follow with an orthopaedic surgeon. Advanced imaging was obtained followed by computed tomography–guided biopsy of the right hip to include cartilage and bone. The cultures were negative for growth. An incision and debridement were performed, and necrotic bone was found. Subsequently, an antibiotic spacer was placed secondary to osteomyelitis. Blood cultures and tissue polymerase chain reaction 16S ribosomal RNA were positive for Haemophilus haemolyticus. Discussion: Culture-negative osteomyelitis remains a treatment challenge. Several organisms have the potential to cause osteomyelitis. Unfortunately, a high percentage of patients have fallen into the category of culture-negative disease. This is a case report discussing an immunocompetent patient with a rarely reported cause of osteomyelitis and how to assist with definitive diagnosis of culture-negative cases.

Osteomyelitis of Jaw Bone due to Aspergillosis in Post-COVID-19 Patients: An Observational Study.

In the second wave of COVID-19 pandemic, there has been an increase in number of cases with Post-COVID-19 fungal osteomyelitis of jaws. Aspergillosis was found to be one of the causes of osteomyelitis of jaw bones in these patients. To evaluate the incidence and pattern of osteomyelitis of jaw due to aspergillosis in post-COVID-19 patients and to discuss the management protocol of the same. Data were obtained at our institution from the period of January 2021 to June 2021. Patients of all age groups with Post-COVID-19 osteomyelitis of jaw due to aspergillosis and those with combined aspergillosis and mucormycosis infection were included. Patients having rhino-orbito-cerebral fungal infection were excluded. A total of 47 patients reported to our center. Demographically the average age of the patients was 49.11years with 72% being males. All 47 patients (N = 100%) had received steroids. 21 of them (N = 44.7%) had diabetes mellitus and 14 (N = 29.8%) patients had other comorbidities. Out of 47 patients, 42 (N = 89.7%) patients were diagnosed with aspergillosis and the remaining 5 (N = 10.3%) cases had a mixed fungal infection of mucormycosis and aspergillosis. On fungal culture Aspergillus flavus was the most common species detected followed by Aspergillus niger and Aspergillus fumigatus. All patients were treated with oral Voriconazole and local surgical debridement. Prompt laboratory testing such as a timely KOH mount, galactomannan test, beta-D-glucan test, histopathology of tissue specimens could help to give an early and definitive diagnosis. The mortality rate we encountered in this study was nil. Early and definitive diagnosis and immediate initiation of antifungal drug therapy and surgical intervention will significantly reduce the rate of morbidity and mortality.

Isolated cervical Cutibacterium acnes osteomyelitis in a patient with no primary source of infection – A case report and review of the literature

Background: Cervical vertebral osteomyelitis (CVO) is a rare pathology that leads to progressive osseous degradation and eventual loss of bone putting the patient at risk of devastating neurological injury in the event of bony collapse or instability. Cutibacterium acnes formerly called Propionibacterium acnes is rare, but within the last two decades has been an increasingly reported cause of osteomyelitis. The majority of C. acnes vertebral osteomyelitis cases have been reported in patients with a history of prior invasive procedures where direct contamination at the time of procedure was suspected as the underlying etiology. Case Description: We report a unique case of an otherwise healthy 39-year-old male with no prior history of invasive procedures who presented with CVO secondary to C. acnes. He underwent surgical debridement and fusion in conjunction with antibiotic treatment. The patient recovered well and a 2-year follow-up with serial imaging showed no evidence of disease recurrence. Conclusion: C. acnes is an under-recognized and under-reported etiology of spine infections. Clinicians should be aware of the pathological potential and atypical presentation of C. acnes vertebral osteomyelitis.

Bacteriological Etiologic Diagnosis, Mode of Infection and Management of Chronic Osteomyelitis: A Prospective Hospital-Based Study in Bangladesh

Background: There are different factors responsible for chronic osteomyelitis. Objective: The purpose of the present study was to find out the bacteriological aetiology of chronic osteomyelitis patients. Methodology: This prospective hospital-based study was conducted in the Department of Orthopaedic and Traumatology at Cox’s Bazar Medical College Hospital, Cox’s bazar, Bangladesh from January 2019 to June 2022 for a period of three and half years. Eligible patients for enrolment in the present study had to sustain an osseous infectious process confirmed by radiological findings lasting more than 2 weeks without acute symptomatology or few contributory laboratory results. The bacteriological aetiology were recorded and the antimicrobial sensitivity testing were performed by dis diffusion test. Results: A total number of 89 cases of osteomyelitis patients were recruited for this study. The mean age with the SD of study population was 11.5±7.89 years with the range of 1 to 42 years. Infected scabies was the most common cause osteomyelitis among the study population which was 42.0% cases in children group; however, there was no cases in adult group. Otitis media, rhinitis dental caries were also found among the children which were 25.0% cases, 5.0% cases, 18.0% cases respectively. Among adult group implant surgery was the most common cause of osteomyelitis which was 65.0% cases. Most common bacterial isolate was Staphylococcus aureus which was 29(32.6%) cases. Coagulase Negative Staphylococcus (CoNS) and Proteus species were the second most common isolated bacteria which was 17(19.1%) cases in each. Gram negative bacteria like Escherichia coli and Pseudomonas species were the most common isolated bacteria which were 11(12.4%) cases and 9(10.1%) cases respectively. Conclusion: In conclusion implant surgery is the most common cause of osteomyelitis and Staphylococcus aureus is the most common isolated bacteria. Bangladesh Journal of Medical Microbiology, January 2022;16(1):8-13

A Very Rare Pathogen of Osteomyelitis: Alcaligenes faecalis.

To the Editors: Alcaligenes faecalis is a Gram-negative, rod-shaped, oxidase-positive, catalase-positive, obligate aerobic, motile and nonfermenting bacteria.1 It is commonly found in the environment (soil or water) and in the human gut.2A. faecalis has been associated with various infections such as bacteremia, meningitis, endophthalmitis, endocarditis, skin and soft tissue infections, urinary tract infections, peritonitis, otitis media and pneumonia.3 Here, we present 2 patients with osteomyelitis due to A. faecalis, a rarely reported clinical condition in the literature. Patient 1: An 18-year-old female with a medical history of operated for meningomyelocele and pes cavus was admitted with worsening pain in her right lower extremity. On admission, she was afebrile with normal vital signs there was a chronic ulcerated wound with seropurulent discharge on the right foot. On the laboratory evaluation, there was no leukocytosis, C-reactive protein, and procalcitonin were negative, erythrocyte sedimentation rate was 35 mm/h. Clindamycin 30 mg/kg/d and cefotaxime 200 mg/kg/d intravenously (IV) were administered empirically. The contrast-enhanced magnetic resonance imaging showed cellulitis in soft tissue and osteomyelitis in the bone at the level of the 5th finger metatarsal base and proximal shaft (Fig. 1). Wound debridement was performed by orthopedics. She developed emesis and rash on day 4 and the antibiotic was changed to IV ciprofloxacin (30 mg/kg/d). Intraoperative wound culture grew A. faecalis which was sensitive to ampicillin, cefotaxime and gentamicin. Due to clinical improvement, treatment with ciprofloxacin continued and she was discharged after 15 days of IV therapy. The total treatment is planned to be completed in 8 weeks.FIGURE 1.: MRI (T2 weighted) showing osteomyelitis of the right foot. MRI indicates magnetic resonance imaging.Patient 2: A 15-year-old girl presented with a chronic ulcerated wound on her right foot. She had been operated twice for meningomyelocele and had pes planovalgus. She was afebrile and there was a chronic wound without any discharge on her right foot on admission. Laboratory evaluation revealed negative acute phase reactants and erythrocyte sedimentation rate was 24 mm/h. The empirical treatment was administered as IV cefotaxime and clindamycin. The contrast-enhanced magnetic resonance imaging showed findings suggestive of active osteomyelitis on the right calcaneus (Fig. 1). Orthopedics performed wound debridement and inserted vacuum-assisted closure therapy system. A. faecalis growth was detected in the tissue culture which was sensitive to ceftazidime and meropenem but resistant to amikacin. Her treatment was changed to IV ceftazidime (150 mg/kg/d). After vacuum-assisted closure treatment, it was planned to perform tissue repair by plastic surgery and to continue antibiotherapy IV due to the resistance pattern of the microorganism. Opportunistic infections and antimicrobial resistance associated with A. faecalis have been reported but osteomyelitis due to A. faecalis was documented in a few patients with diabetic foot ulcers in the literature.4 It is usually sensitive to beta-lactam antibiotics and trimethoprim/sulfamethoxazole and resistant to aminoglycosides and tetracyclines.5 Most of the previously documented cases have been successfully treated with amoxicillin/clavulanic acid but antibiotic resistance is an emerging problem. In summary, we present 2 patients with osteomyelitis due to A. faecalis, a rare cause of osteomyelitis. In addition to surgery, medical treatment should be arranged based on the antibiotic susceptibility results for successful and appropriate treatment.

Application of G-quadruplex aptamer conjugated MSNs to deliver ampicillin for suppressing S. aureus biofilm on mice bone

Staphylococcus aureus is a common bacterial agent of biofilm formation in medical environments. The formed biofilm of this bacterium in bone tissue is one of the main causes of osteomyelitis, which is a serious health issue. Due to the importance of this infection after traumatic injuries or surgical intervention, it is necessary to develop a system that could release the antibiotics at the site of injury, specifically and gradually. The current study aimed to develop a nanosystem composed of single-stranded G-quadreplex DNA aptamer as the bio-recognition element, mesoporous silica nanoparticles (MSNs) as the carrier for gradual drug release, and Ampicillin as the cargo to be delivered to the site of infection. In silico methods were used to select an optimum binding aptamer against protein A of S. aureus . The binding of aptamer was confirmed via gel retardation assay, DLS, and Zeta potential analyses. The loading of the drug was confirmed by the FTIR method, and the drug release investigation showed almost 30 % of drug release via 48 h dialysis assay. The acquired results from the biofilm suppression assay indicated that this system provides a significant inhibitory effect against the S. aureus biofilm and has a high potential for the desired drug release to prevent the formation of biofilm, and could destroy the biofilm on the mice bone. The results of the MTT assay proved that this system does not pose a significant toxicity thread for MCF-7 cell viability, as a model for eukaryotic cells. In vivo studies are required to further confirm the efficacy of this system against S. aureus biofilm on bone.

Bacteriological profile of osteomyelitis patients in government hospital, Ambikapur

Osteomyelitis is an infection and inflammation of the bone. Bacteria are the primary cause of osteomyelitis. Infections with fungi and viruses can also cause it.It usually affects children and others who are immunocompromised. Although bacteria cannot colonise bone ordinarily, events such as trauma, ischemia, surgery, the presence of foreign particles, or the insertion of prostheses can disrupt bone integration, eventually leading to infection.AIM : To study Bacteriological profile of osteomyelitis patients in Government Hospital, Ambikapur. Material And Material: During the study period of April2021 to Oct 2021 for this study 30 patients who were diagnosed clinically and radiologically as a case of Chronic Osteomyelitis are participating in this study. The risk factors for Chronic Osteomyelitis were obtained from patient case sheets with the help of orthopedic surgeons in the department of orthopedic RSDKSGMC and Hospital.In this study, the total number of cases Chronic Osteomyelitis considered was 30.with age group of 1-60 years and both the sexs. Conclusion: Chronic osteomyelitis is a chronic disease that affects the long bones, particularly the femur and tibia, and is most common in adults. Haematogenous Osteomyelitis is becoming less common as antibiotics become more widely available and children's growing bones have a higher vascular metaphysis.

Микроабсцессы как возможная причина рецидива хронического остеомиелита

Introduction It is known that the density of the cortical plate of long bones in patients with chronic osteomyelitis changes throughout its extension. However, the nature of structural disorders in the cortical layer outside the inflammation zone has not been studied well. Purpose To study the structural features of the cortical plate of the femur and tibia outside the focus of inflammation to identify microcavities and microabscesses. Material and methods The study is retrospective conducted at one center. Evidence level IV. In 92 patients with chronic osteomyelitis of long bones of the lower extremities, using polypositional radiography and multislice computed tomography (MSCT), the features of radiological morphology of the femur and tibia were studied in order to reveal structural features of the cortical plate and identify microcavities. Results The cause of osteomyelitis in 5 cases was a consequence of hematogenous osteomyelitis, and in 87 cases it developed due to trauma or surgery. The most common location of chronic osteomyelitis was the distal femur and tibia. Anatomical changes in the femur and tibia in all patients had individual differences. Radiological morphological manifestations such as local and general osteoporosis, foci of osteosclerosis, architectonic disorders occurred in all patients. However, the severity of changes in the bone structure was extremely diverse, including the changes in bone density. Conclusion The data obtained indicate that radiological morphological changes in the cortical plate outside the zone of destruction are manifested by formation of microcavities and microabscesses in 15.6 % of patients, what plays an important role in possible recurrence of osteomyelitis.

МСКТ-семиотика мышц при хроническом остеомиелите бедра и голени

Introduction It is known that the function and structure of the muscles of the thigh and lower leg are closely related to the function of the lower limb, which is impaired to one degree or another in all patients with chronic osteomyelitis. However, the nature of structural changes in the muscles, which, in turn, affect the condition of the bones, has not been well studied. Purpose of the work To study the features of changes in the muscles of the thigh and lower leg in patients with chronic osteomyelitis according to MSCT data. Material and methods The study is retrospective conducted at a single centre of Evidence level IV. Multislice computed tomography (MSCT) was used in 112 patients with chronic osteomyelitis of long bones of the lower extremities to study the radiological morphology of the muscles of the thigh and lower leg, including density, muscle belly area, and anatomical features. Twenty patients had chronic osteomyelitis in the area of transosseous elements (pins). The mean age of the patients was 48.5 ± 9.8 years. Males prevailed among the patients (87.5 %). The cause of osteomyelitis in 107 cases was trauma or surgery, five patients had consequences of hematogenous osteomyelitis. Results The results of the study showed that the muscles of the thigh and lower leg in patients with chronic osteomyelitis have pronounced dystrophic changes. In 89.4 % of patients, they were manifested by an increase in the density of the anterior tibial muscle, long extensor of the toes (84.7 %), peroneal muscles (78.5 %) and a decrease in the density of the head of the gastrocnemius muscle (91.3 %). In 10.6 % of the patients, there was a decrease in the density of the anterior tibial muscle, the long extensor of the fingers. In all patients with chronic osteomyelitis of the femur, the density of the muscles of the anterior and posterior groups was reduced, except for the musculus vastus intermedius of the thigh that was characterized by fibrotic changes with an increase in density. Conclusion The data obtained indicate that radiological morphological changes in muscles occur in all patients with chronic osteomyelitis of the femur and lower leg. The most pronounced alterations in the architectonics were in the anterior tibial and gastrocnemius muscles, and the intermediate broad muscle of the thigh.

Antimicrobial Photodynamic Therapy Involving a Novel Photosensitizer Combined With an Antibiotic in the Treatment of Rabbit Tibial Osteomyelitis Caused by Drug-Resistant Bacteria.

Osteomyelitis is deep tissue inflammation caused by bacterial infection. If such an infection persists, it can lead to dissolution and necrosis of the bone tissue. As a result of the extensive use of antibiotics, drug-resistant bacteria are an increasingly common cause of osteomyelitis, limiting the treatment options available to surgeons. Photodynamic antibacterial chemotherapy has attracted increasing attention as a potential alternative treatment. Its advantages are a broad antibacterial spectrum, lack of drug resistance, and lack of toxic side effects. In this study, we explored the impact of the new photosensitizer LD4 in photodynamic antimicrobial chemotherapy (PACT), both alone and in combination with an antibiotic, on osteomyelitis. A rabbit tibial osteomyelitis model was employed and microbiological, histological, and radiological studies were performed. New Zealand white rabbits (n = 36) were randomly divided into a control group, antibiotic group, PACT group and PACT + antibiotic group for treatment. In microbiological analysis, a reduction in bacterial numbers of more than 99.9% was recorded in the PACT group and the PACT + antibiotic group 5 weeks after treatment (p < 0.01). In histological analysis, repair of the damaged bone tissue was observed in the PACT group, and bone repair in the PACT + antibiotic group was even more significant. In radiological analysis, the X-ray Norden score showed that the severity of bone tissue defects or destruction followed the pattern: PACT + antibiotic group < PACT group < antibiotic group < control group.

Hand Swelling in an Adolescent.

Hand Swelling in an Adolescent.

Reactivation of Dormant Tbial Methicillin-Resistant &lt;em&gt;Staphylococcus Aureus&lt;/em&gt; Osteomyelitis after 17 Years: a Case Report

<em>Staphylococcus aureus</em> is the most common cause of osteomyelitis with significant morbidity and mortality outcomes. Methicillin-susceptible <em>Staphylococcus aureus</em> osteomyelitis reactivation years after the primary episode is a well-known phenomenon. However, there are few case reports documenting dormant Methicillin-Resistant <em>Staphylococcus aureus</em> osteomyelitis recurrence years later.

Reactivation of Dormant Tibial Methicillin- Resistant Staphylococcus aureus Osteomyelitis after 17 Years: A Case Report and Literature Review

Introduction: Staphylococcus aureus is the most common cause of osteomyelitis with significant morbidity and mortality outcomes. Methicillin-susceptible Staphylococcus aureus (MRSA) osteomyelitis reactivation years after the primary episode are a well-known phenomenon. However, there are few case reports documenting dormant MRSA osteomyelitis recurrence years later. Our case report of dormant MRSA tibial osteomyelitis reactivation after 17-years, represents one of the longest documented recurrence intervals from initial bout of MRSA, as well as, the diagnostic and therapeutic challenges involved. Case report: A 55-year-old male reports suffering a Gustilo &amp; Anderson grade 1 open left tibial plafond fracture in 2004 that was managed with wound debridement and Taylor Spatial Frame. Initial management was with debridement and primary closure of the wound and application of a Taylor spatial frame (TSF) as definitive management of the fracture. One month following application of the frame, the patient reports he suffered a pin site infection. This was developed into MRSA osteomyelitis. The wound underwent surgical debridement and once the fracture was consolidated enough at three months, removal of external frame and intramedullary reaming and irrigation was performed. No further soft tissue coverage was required. The patient was treated with a prolonged course of intravenous vancomycin, followed by oral clindamycin. Since this episode, the patient has been asymptomatic and denied any further hospitalisations with return to full function without limitations. The patient does not report any recurrent wounds, discharge, sinus or pain. Seventeen years later, after a closed to the knee, the patient present febrile with knee pain. He was found to have MRSA tibial osteomyelitis, predominantly within the proximal tibia. This was treated with targeted surgical debridement, local antibiotics via an antibiotic impregnated cement nail and prolonged antibiotics. The patient has remained asymptomatic with apparent resolution of infection 6-months post treatment. Conclusion: Our case report represents one of the longest document recurrence intervals of MRSA. Patients with MRSA osteomyelitis should have appropriate treatment and follow-up with orthopaedic surgeons and infectious disease physicians to monitor disease progression and to ensure resolution of the infection.

233. Osteomyelitis of the jaw: A retrospective analysis of clinical, microbiologic characteristics and antimicrobial treatment at a Tertiary Care Medical Center

BackgroundOsteomyelitis of the jaw is a relatively rare entity in the post antibiotic era. The aim of this study is to describe clinical characteristics, microbiology and antibiotics use (oral vs intravenous) for treatment. We review 5 years of experience at Banner University Medical Center-Phoenix (BUMC-P) of proven cases of OM jaw by clinical, pathological, radiological criteria.MethodsRetrospective study of cases. From January 2011 to November 2015 ,157 cases of osteomyelitis of the jaw, we excluded cases of radiation therapy or neoplasia to the head and neck region, a history of antiresorptive medication use. A total of 34 patients with diagnosis of osteomyelitis of the jaw were reviewed. All patients met criteria for diagnosis of osteomyelitis and underwent surgical debridement and received antibiotics that included parenteral, orals and combined. We reviewed clinical, microbiology, antibiotic use. A successful outcome was defined as elimination of clinical symptoms, restoration of function and if available radiographic evidence of arrest and resolution of bony necrosis. ResultsThis retrospective study involved 34 patients. Most common organisms were oropharyngeal flora 22 samples (65%): streptococcus anginosus group. 4 samples grew unusual gram negative bacteria. 10 (29%) samples grew fungal species. Antimicrobial regimen was divided in: intravenous (n=14) (41.2%), oral (n=7) (20.6%) and combination intravenous followed by orals as follows: 13 (38.2 %).The average antibiotic duration was 8.1 + 4.7 weeks. We were able to follow up 30 patients, average follow up was 32.1-44.7 weeks. The overall success rate was (n=24) 80% with uneventful healing and. (n=6) (20%) treatment failure. There was more failure in the oral antibiotics group (n=3). ConclusionThis study is limited by small numbers. Surgery and cultures should guide treatment of osteomyelitis of the jaw. The use of oral antimicrobial therapy was associated to a higher likelihood of treatment failure. Although rarely linked as a cause of osteomyelitis, the authors think that the cultivation of candida spp should prompt appropriate coverage. More study is required to understand the efficacy of oral antimicrobial therapy in treating osteomyelitis of the jaw.Disclosures All Authors: No reported disclosures

Medicated Hydroxyapatite/Collagen Hybrid Scaffolds for Bone Regeneration and Local Antimicrobial Therapy to Prevent Bone Infections.

Microbial infections occurring during bone surgical treatment, the cause of osteomyelitis and implant failures, are still an open challenge in orthopedics. Conventional therapies are often ineffective and associated with serious side effects due to the amount of drugs administered by systemic routes. In this study, a medicated osteoinductive and bioresorbable bone graft was designed and investigated for its ability to control antibiotic drug release in situ. This represents an ideal solution for the eradication or prevention of infection, while simultaneously repairing bone defects. Vancomycin hydrochloride and gentamicin sulfate, here considered for testing, were loaded into a previously developed and largely investigated hybrid bone-mimetic scaffold made of collagen fibers biomineralized with magnesium doped-hydroxyapatite (MgHA/Coll), which in the last ten years has widely demonstrated its effective potential in bone tissue regeneration. Here, we have explored whether it can be used as a controlled local delivery system for antibiotic drugs. An easy loading method was selected in order to be reproducible, quickly, in the operating room. The maintenance of the antibacterial efficiency of the released drugs and the biosafety of medicated scaffolds were assessed with microbiological and in vitro tests, which demonstrated that the MgHA/Coll scaffolds were safe and effective as a local delivery system for an extended duration therapy—promising results for the prevention of bone defect-related infections in orthopedic surgeries.

Ataxic Gait and Back Pain in an Immunocompetent 5-Year-Old Boy

<em>Bartonella henselae</em> is a Gram-negative bacterium and the causative agent of Cat Scratch Disease (CSD). Atypical presentations of <em>B. henselae</em> that involve musculoskeletal, hepatosplenic, or neurologic systems are rare. In this case report, we describe a case of <em>B. henselae</em> osteomyelitis involving the thoracic spine at the level of T2, complicated by both hepatic and splenic granulomas in a 5-year-old generally healthy male patient. Although <em>B. henselae</em> is a rare cause of osteomyelitis, it should be considered in patients with a possible cat exposure, who present with fever, pain, and lymphadenopathy.

#82: Osteomyelitis with Panton-Valentine Leukocidin Producing Staphylococcus aureus Strains, Experience in a Tertiary Pediatric Hospital in Mexico City

Abstract Background S. aureus is the most common cause of osteomyelitis in children. Panton-Valentine leucocidin (PVL) is an exotoxin produced by certain S. aureus strains, which can be detected in both methicillin-sensitive and -resistant strains of staphylococci. Pediatric osteomyelitis by PVL producing S. aureus constitute a rare, but highly critical event. They are characterized by a rapid course of marked inflammation, worsening under conservative therapy, and a high rate of recurrence. No information is available on osteomyelitis and Panton-Valentine leukocidin producing S. aureus in Mexico. Objective The aim of this study was to determine the molecular characterization of S. aureus strains isolated in pediatric patients with osteomyelitis and their clinical features in a tertiary hospital in Mexico City. Methods We conducted a prospective study of children admitted for osteomyelitis, between December 2018 and November 2019, at Instituto Nacional de Pediatría. We obtained an informed consent in children under 12 years of age and an informed assent in children over 12. The confirmation of the S. aureus isolates was performed by amplification and analysis of 16S rRNA and nuc genes. The mecA and pvl genes were detected by PCR, the clinical features were obtained at the admission. Results Fifty patients were included and 26 cases of osteomyelitis were diagnosed, 13 were due to staphylococcus aureus genus and 6 due to S. aureus; all of them were methicillin susceptible and two were PVL producers. Both patients had a severe initial presentation, with extensive local abscesses, and one required three surgical procedures and developed septic pulmonary embolism. The two patients received double antimicrobial treatment and required a long therapy interval. Conclusions Osteomyelitis with Panton-Valentine Leukocidin producing S. aureus seems to be more severe. In patients with severe osteomyelitis, it is essential to detect the PVL toxin because they require early surgical intervention and prolonged intravenous therapy. Our findings suggest that the severity of the osteomyelitis is linked with PVL production more than with methicillin resistance due to that all our isolates were methicillin susceptible.

Finger Rescue Using the Induced Membrane Technique for Osteomyelitis of the Hand.

Background: The induced membrane technique is now commonly used for large diaphyseal bone defects. Recently, several papers reported using the induced membrane technique for hand surgery. We applied this technique with some modifications to treat osteomyelitis of the phalanges. Methods: This study included six men and one woman with a mean age of 56 years. The causes of osteomyelitis included animal bite (n = 3), trauma (n = 3), and an indwelling needle (n = 1). Two-staged surgeries were performed, including an initial stage with radical debridement of the infected tissue and placement of a cement spacer into the bone defect. Four weeks after the first stage, a bone graft was performed. A bone block with cortex was harvested from the iliac crest or radius, and costal cartilage was used for proximal interphalangeal (PIP) joint arthroplasty in two cases. Grafted bones were fixed with a mini screw or an external fixator. Results: In all cases, the infection subsided, and bone union was obtained within two to three months. No absorption of the grafted bone was observed. In the two cases with PIP joint defect, joint motion without pain was preserved at 56° and 26°. Conclusions: A short interval between the two surgical stages of the induced membrane technique could be advantageous for patients in terms of time and financial burden and early rehabilitation of movement. Cortico-cancellous bone grafts were able to maintain bone length and stability with screw fixation. In the cases with PIP joint defects, instead of arthrodesis, we performed PIP arthroplasty using costal cartilage, eventually obtained some motion without pain. The induced membrane technique was useful and technically feasible for treating osteomyelitis in the hand, and secondary joint reconstruction was possible to obtain some motion.