Disseminated Cryptococcus neoformans infection involving multiple bones and lung in an immunocompetent patient: a case report.

BACKGROUND: Cryptococcal osteomyelitis is a rare and potentially serious condition, typically encountered in individuals with compromised immune systems. This case underscores the unusual occurrence of disseminated Cryptococcosis in an immunocompetent person, involving multiple bones and lungs, with Cryptococcus neoformans identified as the causative agent. CASE PRESENTATION: An Indonesian man, previously in good health, presented with a chief complaint of successive multiple bone pain lasting for more one month, without any prior history of trauma. Additionally, he reported a recent onset of fever. On physical examination, tenderness was observed in the left lateral chest wall and right iliac crest. Laboratory findings indicated mildly elevated inflammatory markers. A computed tomography (CT) scan of the chest revealed an ovoid solid nodule in the right lower lung and multifocal osteolytic lesions in the sternum, ribs, and humeral head. A magnetic resonance imaging (MRI) study of the sacrum showed multiple lesions in the bilateral iliac bone and the lower L4 vertebral body. Confirmation of Cryptococcal osteomyelitis involved a fine-needle biopsy and culture, identifying Cryptococcus neoformans in the aspirate. The patient responded positively to targeted antifungal treatments, leading to a gradual improvement in his condition. CONCLUSIONS: This case emphasizes the need to consider Cryptococcus neoformans osteomyelitis in immunocompetent patients with bone pain. A definitive diagnosis involves a fine-needle biopsy for pathology and culture, and prompt initiation of appropriate antifungal treatment has proven effective in preventing mortality.

Identification of pathogen composition in a Chinese population with iatrogenic and native vertebral osteomyelitis by using mNGS.

BACKGROUND: Early antimicrobial therapy is crucial regarding the prognosis of vertebral osteomyelitis, but early pathogen diagnosis remains challenging. OBJECTIVE: In this study, we aimed to differentiate the types of pathogens in iatrogenic vertebral osteomyelitis (IVO) and native vertebral osteomyelitis (NVO) to guide early antibiotic treatment. METHODS: A total of 145 patients, who had confirmed spinal infection and underwent metagenomic next-generation sequencing (mNGS) testing, were included, with 114 in the NVO group and 31 in the IVO group. Using mNGS, we detected and classified 53 pathogens in the 31 patients in the IVO group and 169 pathogens in the 114 patients in the NVO group. To further distinguish IVO from NVO, we employed machine learning algorithms to select serum biomarkers and developed a nomogram model. RESULTS: The results revealed that the proportion of the Actinobacteria phylum in the NVO group was approximately 28.40%, which was significantly higher than the 15.09% in the IVO group. Conversely, the proportion of the Firmicutes phylum (39.62%) in the IVO group was markedly increased compared to the 21.30% in the NVO group. Further genus-level classification demonstrated that Staphylococcus was the most common pathogen in the IVO group, whereas Mycobacterium was predominant in the NVO group. Through LASSO regression and random forest algorithms, we identified 5 serum biomarkers including percentage of basophils (BASO%), percentage of monocytes (Mono%), platelet volume (PCT), globulin (G), activated partial thromboplastin time (APTT) for distinguishing IVO from NVO. Based on these biomarkers, we established a nomogram model capable of accurately discriminating between the two conditions. CONCLUSION: The results of this study hold promise in providing valuable guidance to clinical practitioners for the differential diagnosis and early antimicrobial treatment of vertebral osteomyelitis.

Management of Chronic Osteomyelitis and Antibiotic Stewardship; An Effort to Delay the Post-Antibiotic Era.

OBJECTIVE: To develop an effective antimicrobial strategy for the management of chronic osteomyelitis. STUDY DESIGN: Observational study. Place and Duration of the Study: Departments of Microbiology and Orthopaedics, Combined Military Hospital Malir, Karachi, Pakistan, from January 2021 to February 2022. METHODOLOGY: Bone biopsies of 45 enrolled participants were taken for microbiological evaluation. Intravenous antibiotic therapy was begun as per empirical therapy based on the local antibiogram and antibiotic policy. Once the susceptibility pattern was available, targeted therapy started and continued for 28 to 42 days. Patients were evaluated based on inflammatory markers and clinical conditions for a minimum of six months to a maximum of one year. RESULTS:  Out of the 45 patients, the majority 29% were soldiers, 40% belonging to the age group of 31-60 years. The common predisposing factor was trauma/fractures followed by diabetes and implants leading to chronic sinus discharge and decubitus ulcers. The most commonly isolated organism was Staphylococcus aureus (38%) followed by Methicillin-resistant Staphylococcus aureus (MRSA) (31%). Cotrimoxazole and Rifampicin turned out to be good treatment options. Only 4.4% showed unsatisfactory prognosis, nonetheless, no mortality was observed during the course of treatment. CONCLUSION: In this study, highly resistant strains were observed with limited treatment options for chronic osteomyelitis, however, effective stewardship programmes with accurate diagnostic reporting and judicious use of antimicrobials can prevent overuse of the valuable resources. KEY WORDS: Antimicrobial stewardship, Osteomyelitis, Methicillin-resistant Staphylococcus aureus, Empirical therapy, Antimicrobial resistance.

Non-vertebral Mycobacterium avium complex osteomyelitis in an immunocompetent patient.

Mycobacterium avium complex (MAC) is a ubiquitous soil pathogen that is an uncommon cause of diseases in immunocompetent patients. In this case, we describe the presentation of an otherwise healthy man in his 50s presenting with months of malaise and severe hip pain, with aspiration initially yielding no bacteria and presumed fastidious infection. He was treated with irrigation and debridement, surgical stabilisation of the femoral neck and conventional broad-spectrum antibiotics with final cultures diagnostic of MAC osteomyelitis. This case serves to demonstrate the importance of clinical suspicion and appropriate workup of this unusual case of MAC hip osteomyelitis in an otherwise immunocompetent patient.

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

PURPOSE: Achromobacter 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 PRESENTATION: We 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. CONCLUSIONS: Atypical 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.

Pediatric Multidrug-Resistant Disseminated Tuberculosis Presenting as Small Finger Tuberculous Osteomyelitis: A Case Report.

CASE: We report a case in the United States of a 12-year-old girl with multidrug-resistant tuberculous (MDR-TB) osteomyelitis of the hand managed with surgical debridement and second-line anti-TB therapy. The disease course was complicated by dissemination and multifocal progression. CONCLUSION: Despite early intervention, multidrug resistance makes TB treatment challenging and facilitated progression to disseminated disease in this case. We review the difficulties in diagnosis and treatment of pediatric MDR-TB.

Spatiotemporal Synergism in Osteomyelitis Treatment with Photoactivated Core-Shell Zinc Oxide/Silver Sulfide Heterogeneous Nanoparticles.

Osteomyelitis is primarily caused by bacterial infections, and treatment requires precise sequential therapy, including antibacterial therapy in the early stages and bone defect reconstruction in later stages. We aimed to synthesize core-shell-structured zinc oxide/silver sulfide heterogeneous nanoparticles (ZnO/Ag2S NPs) using wet chemical methods. Using density functional theory and ultraviolet photoelectron spectroscopy, we showed that the optimized band structure endowed ZnO/Ag2S NPs with photodynamic properties under near-infrared (NIR) irradiation. Moreover, ZnO/Ag2S NPs exhibited a distinguished and stable photothermal performance within the same wavelength range. With single-wavelength irradiation, ZnO/Ag2S NPs achieved a bifunctional antibacterial effect during the acute stage of osteomyelitis. Antibacterial action was confirmed through colony-forming unit (CFU) counting assays, scanning electronic microscopy (SEM) observations, live-dead staining, growth curves, and quantitative real-time polymerase chain reaction (qPCR) assays. The Ag2S coating on the NPs realized the sustained release of zinc ions, thereby controlling the zinc ion concentration. Alkaline phosphatase (ALP) staining, alizarin red S (ARS) staining, and qPCR assays confirmed that the ZnO/Ag2S NPs exhibited good osteogenic effects in vitro. These effects were verified in an in vivo mouse femur model during chronic stages using micro-computed tomography (micro-CT) and histological analysis. This study provides a novel biocompatible core-shell nanomaterial for the two-phase treatment of osteomyelitis, contributing to versatile nanotherapies for infections and inflammation.

Osteomyelitis by Microsporum canis and Staphylococcus spp. in cat (Felis catus) - case report.

BACKGROUND: Staphylococcus spp and Microsporum canis are zoonotic microorganisms which can cause infections and systemic diseases. The bone infection is usually caused by invasion of pathogen through the hematologic route. Mixed osteomyelitis caused by bacteria and fungi is rare, and to date, there have been no reports of mixed osteomyelitis with Staphylococcus spp. and Microsporum canis. CASE PRESENTATION: This essay reports an atypical presentation of mixed osteomyelitis (Staphylococcus spp. and Microsporum canis) in a domestic cat. A 15-month-old female Persian cat was presented to a veterinary service; the main complaint was the appearance of a nodule in the mandibular ventral rostral region. A radiographic exam performed on the animal showed proliferative and osteolytic bone lesions. The patient was submitted to a biopsy for histopathological evaluation, along with bacterial and fungal cultures. Results showed mixed osteomyelitis by Staphylococcus spp. and Microsporum canis. Microbial Sensitivity Test was performed to choose a more suitable treatment. Two surgical procedures were executed to resect and curette the lesion, and treatments with anti-inflammatory, antibiotic, and antifungal drugs were established, showing a positive clinical evolution. After 8 months of treatment, the patient's owner moved to a different city, and the animal was seen by other veterinarians, who followed along with the same treatment. However, due to complications and a diminishing quality of life over 4 years of diagnosis, the patient was euthanized. CONCLUSION: Given the above, mixed osteomyelitis is difficult to treat and can cause losses of life quality resulting death, especially in infections where M. canis is the agent causing the disease. Bacterial osteomyelitis is more frequently reported. But the lack of investigation of microorganisms other than bacteria, such as fungal cases, may imply in underdiagnosed cases. Treatment of osteomyelitis can be difficult considering the difficulties in isolating the pathological agent, resistance to the drug used, prolonged treatment time, and cost.

Soft tissue infection and osteomyelitis caused by Mycobacterium farcinogenes after heart surgery: Case report and literature review of human cases.

Mycobacterium farcinogenes (M. farcinogenes) is rapidly growing mycobacterium, belonging to non-tuberculous mycobacterial (NTM). M. farcinogenes is an exceedingly rare causative agent of human infection. Only seven cases with M. farcinogenes infections in humans were reported. This is a case of soft tissue infection and osteomyelitis caused by M. farcinogenes after heart surgery. Microbial identification was achieved by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The clinical outcome was favorable after surgical debridement and 4-month antibiotics treatment. We also provide a comprehensive literature review on this disease.

Clinical outcomes and complications of S53P4 bioactive glass in chronic osteomyelitis and septic non-unions: a retrospective single-center study.

INTRODUCTION: Dead space management following debridement surgery in chronic osteomyelitis or septic non-unions is one of the most crucial and discussed steps for the success of the surgical treatment of these conditions. In this retrospective clinical study, we described the efficacy and safety profile of surgical debridement and local application of S53P4 bioactive glass (S53P4 BAG) in the treatment of bone infections. METHODS: A consecutive single-center series of 38 patients with chronic osteomyelitis (24) and septic non-unions (14), treated with bioactive glass S53P4 as dead space management following surgical debridement between May 2015 and November 2020, were identified and evaluated retrospectively. RESULTS: Infection eradication was reached in 22 out of 24 patients (91.7%) with chronic osteomyelitis. Eleven out of 14 patients (78.6%) with septic non-union achieved both fracture healing and infection healing in 9.1 ± 4.9 months. Three patients (7.9%) developed prolonged serous discharge with wound dehiscence but healed within 2 months with no further surgical intervention. Average patient follow-up time was 19.8 months ± 7.6 months. CONCLUSION: S53P4 bioactive glass is an effective and safe therapeutic option in the treatment of chronic osteomyelitis and septic non-unions because of its unique antibacterial properties, but also for its ability to generate a growth response in the remaining healthy bone at the bone-glass interface.

N6 methyladenosine eraser FTO suppresses Staphylococcus aureus-induced ferroptosis of bone marrow mesenchymal stem cells to ameliorate osteomyelitis through regulating the MDM2/TLR4/SLC7A11 signaling pathway.

Osteomyelitis is a bone destructive inflammatory disease caused by infection. Ferroptosis is closely related to multiple inflammatory diseases, but the role of ferroptosis in Staphylococcus aureus (SA)-induced osteomyelitis remains unknown. In the present study, we found that SA treatment promoted the accumulation of iron, Fe2+ , lipid peroxide, and malondialdehyde, increased TFRC and reduced FTH1 and GPX4 to trigger ferroptosis in rat bone marrow mesenchymal stem cells (BMSCs). Interestingly, increased level of N6 methyl adenosine (m6A) modification along with decreased expression level of m6A eraser FTO were observed in SA-induced BMSCs, while upregulating FTO alleviated SA-triggered ferroptosis and protected cell viability in BMSCs. Mechanistically, MDM2 was identified as a target of FTO-mediated m6A demethylation, and FTO upregulation promoted MDM2 instability to downregulated TLR4 signal and elevate the expression of SLC7A11 and GPX4 in SA-induced BMSCs. Functional recovery experiments verified that overexpressing MDM2 or TLR4 reversed the inhibiting effect of FTO upregulation on ferroptosis in SA-treated BMSCs. Additionally, FTO upregulation restrained ferroptosis and pathological damage to bone tissue in SA-induced osteomyelitis model rats. Altogether, m6A eraser FTO alleviates SA-induced ferroptosis in osteomyelitis models partly through inhibiting the MDM2-TLR4 axis.

Acute Hematogenous Osteomyelitis of the Pelvis in Children.

BACKGROUND: Pelvic involvement has been reported in 3%-14% of acute hematogenous osteomyelitis (AHO) cases in children. One guideline suggests need for a longer antibiotic course in pelvic AHO, however, recent data are lacking. We describe the clinical course of children with pelvic AHO and compare it to nonpelvic AHO. METHODS: A retrospective review of patients with a diagnosis of AHO admitted to Texas Children's Hospital from January 2012 to December 2020 was conducted. Patients 6 months-<19 years old and with ≤14 days of symptoms at admission were eligible. Patients with sickle cell disease or immunocompromised were excluded. Wilcoxon rank-sum test assessed for differences between continuous variables and Fisher exact for categorical variables using STATA 17. RESULTS: We compared 104 cases of pelvic AHO to 314 cases of nonpelvic AHO. Patients had similar microbiology, length of stay and length of antibiotic therapy. Patients with pelvic AHO had pyomyositis identified by magnetic resonance imaging more often (28.8 vs. 9.4%, P < 0.001) and bone abscess less often (22.1 vs. 46.5%, P < 0.001). Rates of chronic complications were comparable between patients with pelvic AHO and nonpelvic AHO (8.4% vs. 15.1%, P = 0.1). Nineteen patients (18.3%) with pelvic AHO received ≤30 antibiotic days without complications, but they had less need for intensive care or bone abscesses than patients treated longer. CONCLUSIONS: Pelvic AHO in children may be more frequent than previously reported but is not associated with more complications. Four weeks of therapy may be sufficient in selected patients. Prospective studies to compare outcomes with different lengths of therapy are needed.

Injectable Nano-Micro Composites with Anti-bacterial and Osteogenic Capabilities for Minimally Invasive Treatment of Osteomyelitis.

The effective management of osteomyelitis remains extremely challenging due to the difficulty associated with treating bone defects, the high probability of recurrence, the requirement of secondary surgery or multiple surgeries, and the difficulty in eradicating infections caused by methicillin-resistant Staphylococcus aureus (MRSA). Hence, smart biodegradable biomaterials that provide effective and precise local anti-infection effects and can promote the repair of bone defects are actively being developed. Here, a novel nano-micro composite is fabricated by combining calcium phosphate (CaP) nanosheets with drug-loaded GelMA microspheres via microfluidic technology. The microspheres are covalently linked with vancomycin (Van) through an oligonucleotide (oligo) linker using an EDC/NHS carboxyl activator. Accordingly, a smart nano-micro composite called "CaP@MS-Oligo-Van" is synthesized. The porous CaP@MS-Oligo-Van composites can target and capture bacteria. They can also release Van in response to the presence of bacterial micrococcal nuclease and Ca2+, exerting additional antibacterial effects and inhibiting the inflammatory response. Finally, the released CaP nanosheets can promote bone tissue repair. Overall, the findings show that a rapid, targeted drug release system based on CaP@MS-Oligo-Van can effectively target bone tissue infections. Hence, this agent holds potential in the clinical treatment of osteomyelitis caused by MRSA.

Evaluating the efficacy of combined flap coverage, antibiotic-loaded bone cement and negative pressure irrigation in traumatic osteomyelitis management.

Traumatic osteomyelitis with accompanying soft tissue defects presents a significant therapeutic challenge. This prospective, randomised controlled trial aims to evaluate the efficacy of antibiotic-impregnated bone cement, flap coverage and negative pressure sealed irrigation in the management of traumatic osteomyelitis complicated by soft tissue defects. A total of 46 patients with clinically diagnosed traumatic osteomyelitis and soft tissue defects were randomised into a control group (n = 23) and an observation group (n = 23). The control group underwent standard flap coverage and negative-pressure lavage, while the observation group received an additional treatment with antibiotic-loaded bone cement. Efficacy was measured based on clinical criteria, surgical metrics and morphometric assessment of bone and soft tissue defects. Statistical analyses were performed using SPSS version 27.0. The observation group, treated with an integrated approach of flap coverage, negative pressure wound therapy (NPWT) and antibiotic-impregnated bone cement, demonstrated significantly higher overall treatment efficacy (91.3%) compared to the control group, which received only flap coverage and NPWT (65.2%) (p < 0.01). This enhanced efficacy was evidenced through various outcomes: the observation group experienced reduced surgical times, shorter hospital stays, fewer dressing changes and accelerated wound healing, all statistically significant (p < 0.001). Additionally, a quantitative analysis at 6-month post-treatment revealed that the observation group showed more substantial reductions in both bone and soft tissue defect sizes compared to the control group (p < 0.001). The multi-modal treatment strategy, combining skin flap coverage, antibiotic bone cement and negative-pressure irrigation, showed marked efficacy in treating traumatic osteomyelitis and associated soft tissue defects. This approach accelerated postoperative recovery and lowered costs.

Hospital at Home Program for the Treatment of Pediatric Osteoarticular Infections.

OBJECTIVES: Hospital at home (HAH) replaces acute inpatient hospital care for selected patients by providing care in their homes. We sought to describe the characteristics, management, and complications of patients with osteoarticular infections (OAIs) treated in an HAH program and its economic impact. METHODS: We conducted a retrospective observational study evaluating an HAH program in a pediatric hospital in Spain, describing the characteristics of patients with confirmed OAIs requiring intravenous antibiotic therapy admitted to this program between January 2019 and December 2022. The program operates as a virtual ward with possible daily visits by physicians and nurses and 24/7 telephone contact. RESULTS: A total of 88 patients (median age, 4.1 years; interquartile range [IQR], 1.7-10.6) with OIAs were admitted to the HAH program. Osteomyelitis (57%) and septic arthritis (29%) were the most frequent infections. Cefuroxime (42%) and cefazolin (39%) were the most frequently prescribed antibiotics. Caregiver self-administration was performed in 99%, allowing multiple daily doses of antimicrobial therapy, 80% by peripheral line. Thirteen patients (15%) had drug-related adverse events, only 3 requiring drug modification. Two patients (2%) were readmitted during HAH, and 1 was readmitted within 30 days of HAH discharge. The median HAH stay was 7 days (IQR, 4-8.75). For osteomyelitis, hospital days lowered from 8.5 days (IQR, 4.5-12) to 4 days (IQR, 3-7) after HAH implementation (P = .005) with 68% per-patient estimated cost savings. CONCLUSIONS: HAH treatment of OAIs is effective and cost-efficient. Patient support by medical and nursing staff, adequate family training, and regular communication are essential to ensure safe home admission.

Hydroxyapatite: An antibiotic recruiting moiety for local treatment and prevention of bone infections.

Treatment of chronic osteomyelitis by radical debridement and filling of the dead space with antibiotic containing calcium sulfate/hydroxyapatite (CaS/HA) bone substitute has shown excellent long-term outcomes. However, in extensive infections, sessile bacteria may remain in bone cells or soft tissues protected by biofilm leading to recurrences. The primary aim of this study was to evaluate if systemically administrated tetracycline (TET) could bind to pre-implanted HA particles and impart an antibacterial effect locally. In vitro studies indicated that the binding of TET to nano- and micro-sized HA particles was rapid and plateaued already at 1 h. Since protein passivation of HA after in-vivo implantation could affect HA-TET interaction, we investigated the effect of serum exposure on HA-TET binding in an antibacterial assay. Although, serum exposure reduced the zone of inhibition (ZOI) of Staphylococcus aureus, a significant ZOI could still be observed after pre-incubation of HA with serum. We could in addition show that zoledronic acid (ZA) competes for the same binding sites as TET and that exposure to high doses of ZA led to reduced TET-HA binding. In an in-vivo setting, we then confirmed that systemically administered TET seeks HA particles that were pre-implanted in muscle and subcutaneous pouches in rats and mice respectively, preventing HA particles from being colonized by S. aureus. Clinical Significance: This study describes a new drug delivery method that could prevent bacterial colonization of a HA biomaterial and reduce recurrences in bone infection.

Rifampin Based Therapy for Patients With Staphylococcus aureus Native Vertebral Osteomyelitis: A Systematic Review and Meta-analysis.

BACKGROUND: Native vertebral osteomyelitis (NVO) caused by Staphylococcus aureus is associated with high risk of treatment failure and increased morbidity. The role of rifampin-based therapy for the treatment of this condition is controversial. The goal of this systematic review and meta-analysis is to explore the efficacy and safety of rifampin-based therapy for the treatment of S. aureus NVO. METHODS: We searched Cochrane, Embase, Medline, Scopus, and Web of Science databases for studies published up to May 2023, focusing on adults with NVO treated with or without rifampin-containing regimens. A random-effects model meta-analysis estimated relative risks and risk difference with 95% confidence intervals (CI). RESULTS: Thirteen studies (2 randomized controlled trials and 11 comparative cohort studies), comprising 244 patients with S. aureus NVO who received rifampin and 435 who did not, were analyzed. Meta-analysis showed that rifampin-based regimens were associated with lower risk of clinical failure (risk difference, -14%; 95% CI, -19% to -8%; P < .001; I2 = 0%; relative risk, 0.58; 95% CI, .37-.92, P = .02, I2 = 21%). Only 1 study reported on adverse events. All studies had a high or uncertain risk of bias, and the certainty of evidence was rated as very low. CONCLUSIONS: Adjunctive rifampin therapy might be associated with lower risk of S. aureus NVO treatment failure; however, the low certainty of evidence precludes drawing definitive conclusions that would alter clinical practice. A randomized trial is necessary to corroborate these findings.

Quantitative light-induced fluorescence-guided surgery for medication-related osteomyelitis of the jaw.

BACKGROUND: Medication-related osteonecrosis of the jaw (MRONJ) is a challenging condition with increasing incidence, and the lack of clear surgical guidelines poses difficulties in its treatment. METHODS: Quantitative light-induced fluorescence (QLF), which can distinguish between vital and necrotic bone tissue without the need for additional markers, was used to guide minimally invasive surgery in a 75-year-old patient with MRONJ. RESULTS: This study demonstrated that QLF allows the real-time identification of infected and necrotic bone tissue during surgery, enabling precise and minimally invasive resection. We observed spontaneous bone recovery and remodeling in sclerotic bone areas that exhibited autofluorescence using a QLF device, suggesting its potential for preserving the bone tissue. CONCLUSION: This study highlights the promising application of QLF as a valuable photodiagnostic tool in MRONJ surgery, offering a noninvasive and intraoperative device for differentiating pathological bone tissue. This approach can potentially improve the precision of surgical interventions and contribute to improved patient outcomes in MRONJ management.