Lower abdominal cyst complicated with suspected infection following INFIX internal fixation for pelvic fracture: a report of two rare cases.

BACKGROUND: The Internal Fixator (INFIX) is a popular method, known for its minimal invasiveness and short operation time, for treating anterior pelvic ring fractures. Studies have shown that postoperative complications may occur, including anterolateral femoral cutaneous nerve injury, the femoral nerve paralysis, and delayed fracture healing. These complications are believed to be related to surgical stimulation, an excessively long lateral end of the connecting rod, a small distance between the screw and bone surface, insufficient pre-bending of the connecting rod, and difficulties in fracture reduction. CASE PRESENTATION: We report two unique cases of lower abdominal pseudocyst complicated with suspected infection after INFIX treatment of pelvic fractures at our trauma center. Following surgical removal of the internal fixation, resolution of the cysts was observed in both patients, and subsequent postoperative follow-up revealed the absence of any residual sequelae. These cases have not been reported in previous literature reviews. DISCUSSION: The lower abdominal cysts, potentially arising from the dead space created during intraoperative placement of the INFIX rod, may increase infection risk. The etiology remains uncertain, despite the presence of abnormal inflammation markers in both cases, and staphylococcus aureus found in one. These cysts were confined to the lower abdomen, not involving the internal fixation, and hence, only the INFIX was removed. Postoperative oral cefazolin treatment was successful, with resolved pseudocysts and no subsequent discomfort. CONCLUSION: We report two unprecedented cases of post-INFIX abdominal cysts, with a suspected link to intraoperative dead space. Despite uncertain etiology, successful management involved INFIX removal and oral cefixime therapy. These findings necessitate further exploration into the causes and management of such complications.

A case report of iliopsoas abscess and literature review.

RATIONALE: Iliopsoas abscess is a rare acute medical condition. It usually occurs because of the spread of infection from adjacent structures and hematogenous spread. Clinical features include fever, backache, radiating nerve root pain, and leg weakness. When sepsis occurs, prompt recognition is required to initiate appropriate antimicrobial therapy and surgical drainage. PATIENT CONCERNS: A 65-year-old male presented to the outpatient department with a 2-day history of lower back, hip, and leg pain, for which analgesics were administered. During hospitalization, he experienced deterioration, becoming febrile, hypoxic, hypotensive, tachycardiac, and delirious. INTERVENTIONS: The patient was then intubated and ventilated. His family reported an additional history of acupuncture for back pain, which sustained an inflamed wound on his right forearm. Abdominal computed tomography was performed, which confirmed bilateral iliopsoas abscess without involvement of intra-abdominal organs. A preliminary report of blood culture revealed Gram-positive cocci. Echocardiography showed vegetation on the aortic valve, and moderate aortic regurgitation was sustained. He was started on vancomycin along with piperacillin-tazobactam. Ultrasound-guided percutaneous drainage was inserted into the bilateral abscess. Pus and blood yielded methicillin-sensitive Staphylococcus aureus. He remained septic. The repeat computed tomography showed the right abscess enlarged. A repeated echocardiogram showed that the vegetation increased. Further incision and surgical drainage were performed with continuous wash-out. OUTCOME: His condition improved after management and he was discharged to a regional hospital for ongoing care. CONCLUSION: Prompt diagnosis and surgical treatment are essential to improve patient outcomes. The unique aspect of this case is the persistence of the methicillin-sensitive Staphylococcus aureus infection. Centralized surgical services are pivotal in conjunction with robust antimicrobial regimens. LESSON: This case reinforces the importance of high clinical suspicion of an unknown source of sepsis.

Recurrent skin and soft tissue infections (SSTIs) in three family members caused by methicillin-resistant Staphylococcus aureus (MRSA) with Panton-Valentine leukocidin (PVL) exotoxin.

Three family members attended their general practice and emergency department over a 3-month period with recurrent skin and soft tissue infections (SSTIs) such as paronychia, submandibular carbuncle and groin and gluteal abscess requiring surgical drainage. Only when two family members were concurrently admitted with abscesses requiring drainage under general anaesthetic was the definitive diagnosis reached. The wound swabs identified methicillin-resistant Staphylococcus aureus (MRSA) and subsequent identification of the exotoxin Panton-Valentine leukocidin (PVL). Following MRSA decolonisation therapy with mupirocin and octenidine, only one family member has had one recurrence of an SSTI with MRSA isolated from the wound. When patients present with a history of recurrent SSTIs or a family all have had similar presentations, the clinician should consider MRSA with PVL exotoxin infection. Then patients must be referred for confirmation to ensure management is effective for the SSTI and prescribe MRSA decolonisation therapy concurrently to reduce recurrence.

The Commando procedure for mechanical double valve prosthesis endocarditis with destruction of the aortomitral continuity.

Infective endocarditis, particularly after implanting valve prostheses, poses significant surgical challenges, often requiring complex interventions. We describe a case of a 37-year-old male with Staphylococcus aureus endocarditis, unsuccessfully treated with mechanical valve prostheses. Continued infection led to the destruction of the intervalvular fibrous body, necessitating a Commando procedure involving radical debridement and replacement of both aortic and mitral valves with complex patch reconstruction. Prosthesis selection remains contentious, considering recurrence risk and long-term prognosis. Our case underscores timely intervention and meticulous technique in managing such complex situations. It highlights successful strategies for treating infective endocarditis with destruction of aortomitral continuity, emphasizing the pivotal role of the Commando procedure.

Successful conservative management of advanced pyogenic sternoclavicular joint arthritis with osteomyelitis and pulmonary infiltration: a case report.

BACKGROUND: Sternoclavicular joint arthritis is a rare condition that poses considerable diagnostic and therapeutic challenges, leading to severe complications and a high mortality rate. Although surgical interventions are often considered necessary for advanced cases, some reports have suggested that conservative management with antibiotic therapy can be effective in certain cases. However, to our knowledge, there are no reports of successful conservative treatment in cases exhibiting aggressive spread. This report highlights a case of advanced sternoclavicular joint arthritis with bone destruction and pulmonary infiltration, successfully treated conservatively with outpatient antibiotic therapy. CASE PRESENTATION: A 58-year-old Japanese male presented with a 1-month history of left-sided shoulder pain. Contrast-enhanced computed tomography showed abscess formation and clavicular bone destruction, with infiltrative shadows suggesting lung involvement. The diagnosis of sternoclavicular joint arthritis was made, and outpatient oral antibiotic therapy was initiated. The patient exhibited a marked reduction in inflammatory marker levels and symptoms, and antibiotic therapy was discontinued after 3 weeks, with no recurrence observed at a 4-month follow-up. CONCLUSIONS: This case highlights that conservative management with antibiotics can be effective for treating advanced sternoclavicular joint arthritis, emphasizing the need for individualized management and further research into non-surgical treatment options.

Seizing the Hidden Assassin: Current Detection Strategies for Staphylococcus aureus and Methicillin-Resistant S. aureus.

Staphylococcus aureus (S. aureus) is a kind of pathogenic bacteria which can lead to food poisoning, hospital, and community infections. S. aureus and methicillin-resistant S. aureus (MRSA) have become headaches for public health worldwide. Therefore, strengthening the detection of S. aureus and MRSA is a critical step to prevent and control its spread and infection. This review summarized multiple detection methods (electrochemical, optical, and other biosensors) for sensitive and efficient detection of nonresistant and resistant S. aureus. First, we have introduced the principle and methods of detection platform for S. aureus and MRSA. We also contrasted various detection strategies. Finally, the current situation and prospect of S. aureus and MRSA detection in the future are explored in depth, and its development direction of detection methods is also predicted. In this review, we found that although biosensors have shown tremendous brilliance in the field of monitoring, they are currently in the experimental stage. It can be certain that we are very close to entering the commercialization stage. The point-of care testing available to nonprofessionals will become a new direction. We firmly believe that the monitoring system will be more perfect and stable and public life will be healthier and safer.

Portable SERS biosensor based on aptamer-assisted catalytic hairpin assembly signal amplification for ultrasensitive detection of Staphylococcus aureus.

Bacteria infections pose a serious threat to public health, and it is urgent to develop facile and accurate detection methods. To meet the important need, a potable and high-sensitive surface enhanced Raman scattering (SERS) biosensor based on aptamer recognition and catalytic hairpin assembly (CHA) signal amplification was proposed for point-of-care detection of Staphylococcus aureus (S. aureus). The SERS biosensor contains three parts: recognition probes, SERS sensing chip, and SERS tags. The feasibility of the strategy was verified by gel electrophoresis, and the one-step test route was optimized. The bacteria SERS biosensor has a good linear relationship ranging from 10 to 107 CFU mL-1 with high sensitivity low to 5 CFU mL-1, and shows excellent specificity, uniformity, and repeatability on S. aureus identification and enumeration, which can distinguish S. aureus from other bacteria. The SERS biosensor shows a good recovery rate (95.73 %-109.65 %) for testing S. aureus spiked in milk, and has good practicability for detecting S. aureus infected mouse wound, which provides a facile and reliable approach for detection of trace bacteria in the real samples.

Bilateral Facet Joint Septic Arthritis Induced by Acupuncture: A Case Report Highlighting Diagnostic Challenges and the Importance of Early Intervention.

BACKGROUND Facet joint septic arthritis (SAFJ) is a rare clinical entity that is extremely challenging to diagnose, often presenting unilaterally and with nonspecific clinical symptoms. However, SAFJ has significant morbidity and mortality, especially with delayed diagnosis. It becomes all the more important for the clinician to recognize that SAFJ can present bilaterally and be associated with direct inoculation, such as in acupuncture. CASE REPORT A 53-year-old woman with chronic alcoholism and well-controlled type 2 diabetes mellitus was initially admitted for progressively worsening atraumatic lower back pain. Initial non-contrast magnetic resonance imaging (MRI) of the lumbar spine revealed bilateral L4-L5 and L5-S1 nonspecific facet joint effusions. Clinical examination was unremarkable. Biochemically, the patient had mildly elevated inflammatory markers. She was treated conservatively with close outpatient follow-up. However, her back pain progressively worsened, with new-onset lower limb weakness and numbness. Repeat MRI showed L4-L5 bilateral facet joint fluid collection with adjacent bony destruction, as well as posterior paraspinal and epidural fluid collections compatible with L4-L5 bilateral SAFJ with paraspinal and epidural abscesses. Urgent surgical drainage and bilateral lateral facet decompression was performed. Intraoperative cultures revealed methicillin-sensitive Staphylococcus aureus as the causative organism. Postoperatively, 6 weeks of intravenous and oral antibiotics were given with good recovery. CONCLUSIONS We describe a case of bilateral SAFJ following acupuncture that was initially missed. With the increasing prevalence of acupuncture treatment for lower back pain, bilateral SAFJ should be a diagnostic consideration. Detailed clinical history is key; this, as well as a high index of suspicion, early evaluation and treatment, are essential to obtain a favorable outcome.

Case Report: Non-ischemic Papillary Muscle Rupture due to MRSA Myocarditis with Concurrent Thromboembolic Myocardial Infarction Secondary to Infective Endocarditis.

Non-ischemic papillary muscle rupture (PMR) is rare. PMR caused by myocarditis in the presence of concurrent infective endocarditis (IE) and myocardial infarction (MI) has not been described. We report a 46-year-old male with recurrent MRSA bacteremia who presented in septic shock and suffered cardiac arrest. Echocardiography revealed acute mitral valve regurgitation resulting from posteromedial PMR. An intra-aortic balloon pump was implanted. Angiography revealed thrombotic occlusion of a small distal left circumflex artery. Emergent mitral valve replacement surgery was performed. MRSA myocarditis and IE were diagnosed by tissue cultures. Coexistence of myocarditis, IE, and MI poses a challenge in determining etiology.

Evaluation of Vitek-2 and MicroScan ASTs directly from positive blood culture: A cost-effective 24-h reduction for Enterobacterales and staphylococci.

The reduction of antimicrobial susceptibility testing (AST) time-to-result is a central need, especially in sepsis treatment. The current automated rapid ASTs are still too expensive for many laboratories. We aimed to evaluate three pre-treatment methods for a same-day inoculation on both automated AST platforms available in our laboratory. We tested 100 Enterobacterales or staphylococci positive bottles. We obtained good results with the different methods and instruments. In particular, Vitek-2 showed good performances with Enterobacterales AST when inoculated with bacterial pellet (96.6% categorical agreement - CA-, 93.3% essential agreement - EA). Also short-term incubation colonies for staphylococci AST had acceptable CA (94.2%), even if with 77.5% EA. MicroScan system for staphylococci AST with both short-term incubation and direct blood inoculation reached >95% CA, but 92.5% and 83.6% EA, respectively. On the other hand, Enterobacterales AST showed optimal performances only with bacterial pellet inoculation (97.6% CA). In fact, direct blood inoculation showed not acceptable parameters for several molecules. Both systems allow a 24-h reduction in time-to-result, by using the same instruments of routine activity after rapid and cheap pre-treatments.

Wireless implantable bioelectronics with a direct electron transfer lactate enzyme for detection of surgical site infection in orthopaedics.

Periprosthetic infection is one of the most devastating complications following orthopaedic surgery. Rapid detection of an infection can change the treatment pathway and improve outcomes for the patient. In here, we propose a miniaturized lactate biosensor developed on a flexible substrate and integrated on a small-form bone implant to detect infection. The methods for lactate biosensor fabrication and integration on a bone implant are fully described within this study. The system performance was comprehensively electrochemically characterised, including with L-lactate solutions prepared in phosphate-buffered saline and culture medium, and interferents such as acetaminophen and ascorbic acid. A proof-of-concept demonstration was then conducted with ex vivo ovine femoral heads incubated with and without exposure to Staphylococcus epidermidis. The sensitivity, current density and limit-of-detection levels achieved by the biosensor were 1.25 µA mM-1, 1.51 µA.M-1.mm-2 and 66 µM, respectively. The system was insensitive to acetaminophen, while sensitivity to ascorbic acid was half that of the sensitivity to L-lactate. In the ex vivo bone model, S. epidermidis infection was detected within 5 h of implantation, while the control sample led to no change in the sensor readings. This pioneering work demonstrates a pathway to improving orthopaedic outcomes by enabling early infection diagnosis.

Concomitant pyogenic spondylodiscitis and empyema following tongue cancer resection and wisdom tooth extraction: A case report and literature review.

RATIONALE: Pyogenic spondylodiscitis is an infectious spinal disease that causes significant motor dysfunctions. Its diagnosis can be challenging owing to its rapid onset and nonspecific symptoms. PATIENT CONCERNS: A 79-year-old Japanese man with a history of type 2 diabetes mellitus and polymyalgia rheumatica presented to our department with tongue pain. Following partial glossectomy and wisdom tooth extraction under general anesthesia, on 10 postoperative day (POD) the patient developed right-sided abdominal pain and difficulty in walking. On 12 POD, the patient was admitted to a municipal hospital due to respiratory distress and paraplegia. DIAGNOSES: The patient was diagnosed with pyogenic spondylodiscitis and empyema. Blood tests revealed elevated C-reactive protein levels (36.5), white blood cell count (19,570), and neutrophil count (17,867). INTERVENTIONS: The patient received meropenem hydrate 3 g/2 days as empiric antibiotic treatment for acute infection. Upon admission to the emergency department on 16 POD, the lung abscess was drained, hemilaminectomy was performed. OUTCOMES: Blood cultures, sputum tests, and cultures from the thoracic and spinal abscesses drained during surgery revealed methicillin-sensitive Staphylococcus aureus. The infection was successfully managed, and the respiratory disturbance and inflammatory response improved. However, the lower half of the patient body remained paralyzed. Subsequently, the patient was transferred to a rehabilitation facility on 45 POD. The patient continued to undergo functional restoration training, gradually regained function, and eventually achieved the ability to walk with grasping gait. LESSONS: This is the first case report of S aureus causing pyogenic spondylodiscitis and empyema due to blood stream infection from a post-oral surgical wound. Pyogenic spondylodiscitis arising from a secondary hematogenous infection is difficult to diagnose and can lead to severe functional impairment. Prompt and appropriate diagnosis and treatment based on detailed patient interviews, additional blood tests, and computed tomography are essential.

Integrated transcriptomic analysis reveals immune signatures distinguishing persistent versus resolving outcomes in MRSA bacteremia.

Introduction: Staphylococcus aureus bacteremia (SAB) is a life-threatening infection particularly involving methicillin-resistant S. aureus (MRSA). In contrast to resolving MRSA bacteremia (RB), persistent MRSA bacteremia (PB) blood cultures remain positive despite appropriate antibiotic treatment. Host immune responses distinguishing PB vs. RB outcomes are poorly understood. Here, integrated transcriptomic, IL-10 cytokine levels, and genomic analyses sought to identify signatures differentiating PB vs. RB outcomes. Methods: Whole-blood transcriptomes of propensity-matched PB (n=28) versus RB (n=30) patients treated with vancomycin were compared in one independent training patient cohort. Gene expression (GE) modules were analyzed and prioritized relative to host IL-10 cytokine levels and DNA methyltransferase-3A (DNMT3A) genotype. Results: Differential expression of T and B lymphocyte gene expression early in MRSA bacteremia discriminated RB from PB outcomes. Significant increases in effector T and B cell signaling pathways correlated with RB, lower IL-10 cytokine levels and DNMT3A heterozygous A/C genotype. Importantly, a second PB and RB patient cohort analyzed in a masked manner demonstrated high predictive accuracy of differential signatures. Discussion: Collectively, the present findings indicate that human PB involves dysregulated immunity characterized by impaired T and B cell responses associated with excessive IL-10 expression in context of the DNMT3A A/A genotype. These findings reveal distinct immunologic programs in PB vs. RB outcomes, enable future studies to define mechanisms by which host and/or pathogen drive differential signatures and may accelerate prediction of PB outcomes. Such prognostic assessment of host risk could significantly enhance early anti-infective interventions to avert PB and improve patient outcomes.

Purulent lymphadenitis caused by ST59 community-associated Methicillin-resistant Staphylococcus aureus in an infant.

INTRODUCTION: Methicillin-resistant Staphylococcus aureus (CA-MRSA), which has the potential to produce serious infections, was a common cause of skin and soft tissue infections, acute purulent lymphadenitis was rare. CASE REPORT: The patient was a female infant with lumps, tenderness, and fever on the right side of the neck and groin. Laboratory tests suggested a bacterial infection. The diagnosis of acute purulent lymphadenitis was made based on the clinical signs and the results of a supporting exam. After three days, MRSA developed in the secretions of suppurative lymph nodes. Her mother's nasopharyngeal swab sample results revealed MRSA. The genotypes of two bacterial strains that underwent molecular analysis were identical. RESULTS: 17 days after admission, the patient showed signs of clinical recovery. CONCLUSIONS: The incident brought to light the possible spread of CA-MRSA in the Chinese population. Even without a definite path of infection, CA-MRSA should be taken into consideration when the standard treatment for children with acute purulent lymphadenitis is ineffective. Early infancy MRSA acquisition may be mostly caused by maternal-infant horizontal transmission.

Severe necrotizing tracheobronchitis caused by influenza B and methicillin-resistant Staphylococcus aureus co-infection in an immunocompetent patient.

PURPOSE AND METHOD: Necrotizing tracheobronchitis is a rare clinical entity presented as a necrotic inflammation involving the mainstem trachea and distal bronchi. We reported a case of severe necrotizing tracheobronchitis caused by influenza B and methicillin-resistant Staphylococcus aureus (MRSA) co-infection in an immunocompetent patient. CASE PRESENTATION: We described a 36-year-old man with initial symptoms of cough, rigors, muscle soreness and fever. His status rapidly deteriorated two days later and he was intubated. Bronchoscopy demonstrated severe necrotizing tracheobronchitis, and CT imaging demonstrated multiple patchy and cavitation formation in both lungs. Next-generation sequencing (NGS) and bronchoalveolar lavage fluid (BALF) culture supported the co-infection of influenza B and MRSA. We also found T lymphocyte and NK lymphocyte functions were extremely suppressed during illness exacerbation. The patient was treated with antivirals and antibiotics including vancomycin. Subsequent bronchoscopy and CT scans revealed significant improvement of the airway and pulmonary lesions, and the lymphocyte functions were restored. Finally, this patient was discharged successfully. CONCLUSION: Necrotizing tracheobronchitis should be suspected in patients with rapid deterioration after influenza B infection. The timely diagnosis of co-infection and accurate antibiotics are important to effective treatment.

Evaluation of bacteriophage ϕ11 host recognition protein and its host-binding peptides for diagnosing/targeting Staphylococcus aureus infections.

BACKGROUND: Evaluating the potential of using both synthetic and biological products as targeting agents for the diagnosis, imaging, and treatment of infections due to particularly antibiotic-resistant pathogens is important for controlling infections. This study examined the interaction between Gp45, a receptor-binding protein of the ϕ11 lysogenic phage, and its host Staphylococcus aureus (S. aureus), a common cause of nosocomial infections. METHODS: Using molecular dynamics and docking simulations, this study identified the peptides that bind to S. aureus wall teichoic acids via Gp45. It compared the binding affinity of Gp45 and the two highest-scoring peptide sequences (P1 and P3) and their scrambled forms using microscopy, spectroscopy, and ELISA. RESULTS: It was found that rGp45 (recombinant Gp45) and chemically synthesised P1 had a higher binding affinity for S. aureus compared with all other peptides, except for Escherichia coli. Furthermore, rGp45 had a capture efficiency of > 86%; P1 had a capture efficiency of > 64%. CONCLUSION: These findings suggest that receptor-binding proteins such as rGp45, which provide a critical initiation of the phage life cycle for host adsorption, might play an important role in the diagnosis, imaging, and targeting of bacterial infections. Studying such proteins could accordingly enable the development of effective strategies for controlling infections.

Target Recognition Triggered Split DNAzyme based Colorimetric Assay for Direct and Sensitive Methicillin-Resistance Analysis of Staphylococcus aureus.

The accurate and rapid detection of methicillin-resistant Staphylococcus aureus (MRSA) holds significant clinical importance. This work presents a new method for detecting methicillin-resistant Staphylococcus aureus (S. aureus) in clinical samples. The method uses an aptamer-based colorimetric assay that combines a recognizing probe to identify the target and split DNAzyme to amplify the signal, resulting in a highly sensitive and direct analysis of methicillin-resistance. The identification of the PBP2a protein on the membrane of S. aureus in clinical samples leads to the allosterism of the recognizing probe, and thus provides a template for the proximity ligation of split DNAzyme. The proximity ligation of split DNAzyme forms an intact DNAzyme to identify the loop section in the L probe and generates a nicking site to release the loop sequence ("3" and "4" fragments). The "3" and "4" fragments forms an intact sequence to induce the catalytic hairpin assembly, exposing the G-rich section. The released the G-rich sequence of LR probe induces the formation of G-quadruplex-hemin DNAzyme as a colorimetric signal readout. The absorption intensity demonstrated a strong linear association with the logarithm of the S. aureus concentration across a wide range of 5 orders of magnitude dynamic range under the optimized experimental parameters. The limit of detection was calculated to be 23 CFU/ml and the method showed high selectivity for MRSA.