Intraoperative Cultures Research Articles

Foot Abscesses With No Accompanying Wound: Clinical Presentation and Pathogens

Introduction. Acute bacterial infections of the skin and soft tissue are common and often pose serious complications, most commonly caused by Streptococcus species and Staphylococcus aureus. Objective. The authors report clinical presentation and pathogens in patients with a foot abscess and no wound. Methods. The authors retrospectively evaluated the demographics, clinical presentation, and microbiology from 20 patient records. Results. Twenty patients were identified. Fifteen were male (75%), and 10 patients (50%) had DM. Patients presented to the hospital 7.8 ± 4.8 days after onset of symptoms and underwent surgery 2.0 ± 0.9 days from admission. Patients underwent 2.4 ± 1.0 surgeries while admitted. Patients with DM presented with significantly higher erythrocyte sedimentation rate than patients without DM (66.6 ± 46.1 vs 43.3 ± 26.2; P = .02). There were no polymicrobial infections based on deep intraoperative tissue cultures. Seven patients had methicillin-sensitive S aureus (35%), 4 had Streptococcus agalactiae (20%), 3 had methicillin-resistant S aureus (15%), 1 had Streptococcus pyogenes (5%), 1 had Escherichia coli (5%), 1 had Streptococcus dysgalactiae (5%), 1 had an unidentified Streptococcus species (5%), and 2 had no growth (10%). Conclusion. Patients with foot abscess and no wounds had single-pathogen infections, predominantly Staphylococcus and Streptococcus.

SJLA_2024_A16: Unusual Complications of Open Preperitoneal Tension-Free Inguinal Hernia Repair

Background: The purpose of this study is to report two patients referred to our hospital after developing unusual complications attributed to prior open preperitoneal tension-free inguinal hernia repair. Methods: Case # 1 A 75-year-old male developed a left proximal thigh abscess requiring incision and drainage 5 years after open prosthetic, preperitoneal inguinal hernia repair with single-layer mesh. A pelvic computed tomography (CT) scan demonstrated an abscess in the left inguinal preperitoneal space as well as diverticulosis but no diverticulitis. A colonoscopy was negative for any additional findings. The patient underwent groin exploration, debridement of the inguinal canal and sinus tract, and mesh resection followed by JP drain placement. The inguinal defect was repaired utilizing the should ice technique. Intraoperative cultures revealed penicillin-resistant Staphylococcus aureus. The drain was removed on postoperative day nine, and his recovery remains uneventful without hernia recurrence or infectious complications at 11-month follow-up. Case # 2 An 82-year-old man developed progressive left lower extremity edema and disabling claudication 1 month after open prosthetic inguinal hernia repair with a bilayer disc mesh. Venous duplex imaging revealed compression of the left common femoral and external iliac veins. A CT angiogram demonstrated left external iliac and common femoral artery thrombosis and a 5.2 cm fluid collection consistent with hematoma. An inferior vena cava filter was placed. The common femoral artery was controlled after initial exploration revealed a common femoral artery pseudoaneurysm. The mesh was densely adherent to the external iliac vein and was thus not resected. The common femoral artery pseudoaneurysm was repaired and the profunda femoris artery over sewn. An external iliac to superficial femoral artery 8 mm Polytetrafluoroethylene bypass graft was placed. The patient was discharged on systemic anticoagulation without claudication on postoperative day thirteen. Results: Laparoscopic inguinal hernia repair and novel, open techniques and mesh devices have popularized the placement of mesh in the preperitoneal space. Acute, severe vascular complications and latent infectious complications can occur after open, preperitoneal tension-free inguinal hernia repair and may require remedial surgery. CT scans and angiogram pictures are available. Discussion: Laparoscopic inguinal hernia repair and novel, open techniques and mesh devices have popularized the placement of mesh in the preperitoneal space. Acute, severe vascular complications and latent infectious complications can occur after open, preperitoneal tension-free inguinal hernia repair and may require remedial surgery. CT scans and angiogram pictures are available. Conclusion: Laparoscopic inguinal hernia repair and novel, open techniques and mesh devices have popularized the placement of mesh in the preperitoneal space. Acute, severe vascular complications and latent infectious complications can occur after open, preperitoneal tension-free inguinal hernia repair and may require remedial surgery. CT scans and angiogram pictures are available.

The Clinical Outcome of Early Periprosthetic Joint Infections Caused by Staphylococcus epidermidis and Managed by Surgical Debridement in an Era of Increasing Resistance.

A risk factor for the failure of surgical debridement in patients with early periprosthetic joint infections (PJI) is the presence of multidrug-resistant microorganisms. Staphylococcus epidermidis is one of the most isolated microorganisms in PJI and is associated with emerging resistance patterns. We aimed to assess the antibiotic resistance patterns of S. epidermidis in early PJIs treated with surgical debridement and correlate them to clinical outcomes. A retrospective multicentre observational study was conducted to evaluate patients with an early PJI (within 3 months after the index arthroplasty) by S. epidermidis with at least two positive intraoperative cultures. Clinical failure was defined as the need for additional surgical intervention or antibiotic suppressive therapy to control the infection. A total of 157 patients were included. The highest rate of resistance was observed for methicillin in 82% and ciprofloxacin in 65% of the cases. Both were associated with a higher rate of clinical failure (41.2% vs. 12.5% (p 0.048) and 47.3% vs. 14.3% (p 0.015)), respectively. Furthermore, 70% of the cases had reduced susceptibility to vancomycin (MIC ≥ 2), which showed a trend towards a higher failure rate (39.6% vs. 19.0%, NS). Only 7% of the cases were rifampin-resistant. Only the resistance to fluoroquinolones was an independent risk factor for clinical failure in the multivariate analysis (OR 5.45, 95% CI 1.67-17.83). S. epidermidis PJIs show a high rate of resistance. Resistance to fluoroquinolones is associated with clinical failure. Alternative prophylactic antibiotic regimens and optimising treatment strategies are needed to improve clinical outcomes.

Allogenic bone grafts and postoperative surgical site infection: are positive intraoperative swab cultures predictive for a higher infectious risk?

In spine surgery, allogenic bone grafts are often required to ensure bone fusion, however, the main concern regarding their use is the infection risk: therefore, an intraoperative swab for culture test is performed. The cost-effectiveness of these swabs and their influence on the patients' postoperative course have often been questioned. This study aims at determining whether positive spine allograft culture results are predictive of an increased risk of surgical site infection and whether they influence the surgeon's choices in postoperative management.The records of 340 patients who received allogenic bone graft during spinal fusion surgery in our institution were reviewed, for a total of 677 allografts. Each graft was swabbed intraoperatively. All patients were followed clinically for postoperative complications. Infection was diagnosed based on clinical data, blood tests and radiographic images, all assessed by an infectious disease specialist.Only 4 of the 677 allografts used (0.6%) resulted positive at the intraoperative swab culture. Three cultures were positive for Staphylococcus epidermidis and one culture for S. warneri. No clinical infection occurred in any of these patients. Twenty-eight of the 340 patients (8.2%) developed an infection, but none of them had a positive intraoperative swab culture. The most common microbiologic pathogen isolated from this cohort was S. aureus.According to our series, intraoperative swab culture results were not predictive for higher risk of infection and did not affect the clinical behavior of the surgeons in postoperative management.

The concordance between preoperative synovial fluid culture and intraoperative tissue cultures in periprosthetic joint infection: a systematic review.

Background: this systematic review aims to evaluate the concordance between preoperative synovial fluid culture and intraoperative tissue cultures in patients with periprosthetic joint infection (PJI) undergoing total hip (THA) or knee arthroplasty (TKA) revision surgery. Methods: this review was conducted in accordance with the preferred reporting items for a systematic review and meta-analysis of diagnostic test accuracy studies (PRISMA-DTA) statement. Cochrane, Embase, PubMed, and Web of Science databases were searched to identify studies involving patients who had THA or TKA revision surgery for PJI and for whom preoperative synovial fluid culture and intraoperative tissue cultures were performed. Studies were only included if the diagnosis of PJI was based on the EBJIS (the European Bone and Joint Infection Society) or MSIS (Musculoskeletal Infection Society) criteria. Risk of bias was assessed using an amended version of Joanna Briggs Institute's (JBI) critical appraisal checklist for case series. Results: seven studies were included in this review comprising 1677 patients. All studies had a retrospective study design and five studies explored patients undergoing revision surgery of THA or TKA. Concordance rates varied between 52 % and 79 %, but different authors defined and calculated concordance differently. Six studies were judged as having an unclear to high risk of bias and one study as having a low risk of bias. Conclusions: the included studies showed a wide range of concordance rates between preoperative synovial fluid culture and intraoperative tissue cultures and the majority of studies had a high risk of bias. Higher-quality studies are warranted to obtain a more accurate estimate of this concordance rate. We recommend continuing the use of a system such as the EBJIS definition or MSIS criteria when diagnosing PJI.

Alpha-defensin as a diagnostic tool in revision total knee arthroplasties with unexpected positive intraoperative cultures and unexpected culture negative intraoperative cultures.

Unexpected-positive-intraoperative-cultures (UPIC) are common in presumed aseptic revision-total-knee-arthroplasties (rTKA). However, the clinical significance is not entirely clear. In contrast, in some presumably septic rTKA, identification of an underlying pathogen was not possible, so-called unexpected-negative-intraoperative-cultures (UNIC). The purpose of this study was to evaluate the potential use of synovial alpha-defensin (AD) levels in these patients. Synovial AD levels from 143 rTKAs were evaluated retrospectively from our prospectively maintained institutional periprostetic joint infection (PJI) biobank and database. The 2018-International Consensus Meeting (ICM) criteria was used to define the study groups. Samples from UPICs with a minimum of one positive intraoperative culture (ICM 2- ≥ 6) (n = 20) and UNIC's (ICM ≥ 6) (n = 14) were compared to 34 septic culture-positive samples (ICM ≥ 6) and 75 aseptic culture-negative (ICM 0-1). Moreover, AD-lateral-flow-assay (ADLF) and an enzyme-linked-immunosorbent-assay (ELISA) in detecting the presence of AD in native and centrifuged synovial fluid specimens was performed. Concentration of AD determined by ELISA and ADLF methods, as well as microbiological, and histopathological results, serum and synovial parameters along with demographic factors were analysed. AD was positive in 31/34 (91.2%) samples from the septic culture-positive group and in 14/14 (100%) samples in the UNIC group. All UPIC samples showed a negative AD result. Positive AD samples were highly associated with culture positive and histopathological results (p < 0.001). No high-virulent microorganisms (0/20) were present in the UPIC group, compared to infected-group (19/34; 55.9%). High virulent microorganisms showed a positive AD result in 89.5% (17/19) of the cases. Methicillin resistant Staphylococcus epidermis (MRSE) infections had significantly higher AD levels than with methicillin susceptible S. epidermdis (MSSE) (p = 0.003). ELISA and ADLF tests were positive with centrifuged (8/8) and native (8/8) synovial fluid. AD showed a solid diagnostic performance in infected and non-infected revisions, and it provided an additional value in the diagnosis of UPIC and UNIC associated to rTKAs. Pathogen virulence as well as antibiotic resistance pattern may have an effect on AD levels. Centrifugation of synovial fluid had no influence on ADLF results.

Devascularized Bone Surface Culture: A Novel Strategy for Identifying Osteomyelitis-Related Pathogens.

The gold standard for identifying pathogens causing osteomyelitis (OM) is intraoperative tissue sampling culture (TSC). However, its positive rate remains inadequate. Here, we evaluated the efficiency of a novel strategy, known as devitalized bone surface culture (BSC), for detecting OM-related microorganisms and compared it to TSC. Between December 2021 and July 2022, patients diagnosed with OM and received both methods for bacterial identification were screened for analysis. In total, 51 cases were finally recruited for analysis. The mean age was 43.6 years, with the tibia as the top infection site. The positive rate of BSC was relatively higher than that of TSC (74.5% vs. 58.8%, p = 0.093), though no statistical difference was achieved. Both BSC and TSC detected definite pathogens in 29 patients, and their results were in accordance with each other. The most frequent microorganism identified by the BSC method was Staphylococcus aureus. Moreover, BSC took a significantly shorter median culture time than TSC (1.0 days vs. 3.0 days, p &lt; 0.001). In summary, BSC may be superior to TSC for identifying OM-associated pathogens, with a higher detectable rate and a shorter culture time.

S41 Unusual Case of Tongue Deviation

Case: Background: Anti-tumor necrosis factor-α (TNFα) therapy is the mainstay of treatment for inflammatory bowel disease such as Crohn’s Disease (CD) and ulcerative colitis (UC). Despite its widespread use, anti-TNFα leads to significantly altered inflammatory response and increased risk of severe skin and soft tissue infections. Here, we highlight an uncommon presentation of severe soft tissue infection in a patient with ileal CD maintained on anti-TNFα therapy. Case Presentation: A 50-year-old female with a 25-year history of Crohn's ileitis maintained on certolizumab for 3 years presented to the emergency department (ED) with an expanding left, lateral neck mass resulting in decreased cervical range of motion. This was accompanied by a left-sided tongue deviation. She first presented to our ED 8 weeks earlier with severe throbbing headaches without focal neurologic symptoms. A head MRI only showed non-specific T2/FLAIR hyperintensities. Her vital signs and labs were normal, and these headaches were presumed to be complex migraines. Three weeks after her first presentation, she came back to the ED with worsening headaches, neck pain and a new left-sided tongue deviation. Again, her vital signs and laboratory evaluation were normal apart from an ESR of 68 mm/hr (nl: 0-30 mm/hr) and CRP of 10.34 mg/dL (nl<0.5 mg/dL). Her repeat imaging studies did not show any evidence of stroke; however, opacification of the paranasal sinuses and left mastoid air cells were observed. Nonetheless, given her lack of systemic inflammatory symptoms, she was discharged home with close outpatient otolaryngology (ENT) referral. As an outpatient, she was diagnosed with bacterial sinusitis which was treated with a 15-day course of cefdinir and dexamethasone. Her symptoms initially improved; however, she eventually experienced dysphagia with pus drainage from her sinuses. Another antibiotic and steroid course was prescribed. Despite this, approximately 8 weeks after her initial presentation, she developed a rapidly expanding neck mass which prompted her return to the ED. Physical examination revealed a tender neck mass limiting her cervical range of motion and a more pronounced tongue deviation. She was afebrile, non-tachycardiac, and normotensive. Laboratory testing again revealed elevated inflammatory markers (ESR 83 mm/hr, CRP 8.59 mg/dL) but otherwise her WBC was normal (8310 cells/ µL, nl: 10400 cells/µL) with no evidence of sepsis-related end-organ dysfunction (Cr 0.89 mg/dL, AST 20, ALT 55 mg/dL, T-bili 0.3 mg/dL, platelets 348000 platelets/µL). Neck imaging showed multifocal ring-enhancing collections within the left paravertebral soft tissue with left hypoglossal nerve involvement. Intravenous vancomycin, cefepime, and metronidazole were started. Surgical debridement of the left posterior paraspinal abscess was performed. Intraoperative cultures were positive for Streptococcus anginosus. She completed a 6-week course of ceftriaxone but follow up imaging 2 weeks later showed recurrence of her neck abscesses. This again required surgical debridement. Her infections finally cleared with 24 weeks of piperacillin/tazobactam. Her certolizumab remains permanently discontinued. Conclusions: Hallmark symptoms of severe infection may not be present in patients on anti-TNF therapy. A high index of suspicion for an underlying infectious etiology must be maintained when treating this population.

Management and Outcome of Non-Aneurysmal Primary Aortic Infection.

Aortic infection without prior intervention or aneurysm is exceedingly rare. We report the presentation, diagnosis, management, and outcome of patients with this unusual entity. Retrospective chart and imaging review of patients with primary aortic infection. 5 patients (3 male, mean age 71.2years) presented between 2014 and 2022. All had abdominal, back, or flank pain. Four had constitutional symptoms. All were evaluated with a complete blood count; 3 had leukocytosis. Both serum C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were elevated in the 4 patients evaluated with these tests. All were studied with peripheral blood culture on the first hospital day prior to any antibiotic administration. Blood culture was positive in only 1 patient. Computed tomography (CT) scan showed periaortic inflammation without aneurysm in all. Fluorodeoxyglucose positron emission tomography (PET) was obtained in 3 and a radiolabeled leukocyte single-photon emission CT (SPECT) scan was performed in 2. All demonstrated periaortic concentration of the radioisotope consistent with inflammation or infection. Intraoperative cultures were positive in 3. One patient who had a negative intraoperative culture was examined with broad range polymerase chain reaction (PCR) and DNA sequencing which identified a causative bacterium. The other patient with a negative intraoperative culture had periaortic abscess but was on antibiotics preoperatively, potentially confounding the culture. All patients underwent in-situ repair with rifampin impregnated polyester (N = 2), cryopreserved aortic allograft (N = 2), or autogenous femoral vein (N = 1). No patient developed recurrent infection or aortic related complications following surgery with an average follow up of 31.8months (range 8-88months). Patients with primary aortic infection present similarly with the triad of abdominal or back pain, laboratory markers of infection, and imaging demonstrating periaortic inflammation. Patients were treated successfully with in-situ repair. Preoperative identification of a causative organism was difficult, and PCR may be useful to help identify an organism.

Postoperative Infection after Anterior Cruciate Ligament Reconstruction: Prevention and Management.

Infection following anterior cruciate ligament (ACL) reconstruction can be one of the most debilitating complications following ACL reconstruction. Its reported incidence is around 1%. Utilization of vancomycin for presoaking the graft is considered an established method for infection prevention. The role of other agents, such as gentamycin needs further investigation. Staphylococci are the predominant causative pathogens, while particular attention should be paid to fungal infections due to their long-standing, occult process. Recent data demonstrate that hamstrings autograft may be at an elevated risk of being contaminated leading to subsequent septic arthritis. Diagnosis is set by clinical and laboratory findings and is usually confirmed by intraoperative cultures. Treatment varies, mainly depending on the intraoperative assessment. Satisfactory outcomes have been reported with both graft retaining and removal, and the decision is made upon the arthroscopic appearance of the graft and the characteristics of the infection. Of note, early management seems to lead to superior results, while persistent infection should be managed with graft removal in an attempt to protect the articular cartilage and the knee function.

Peripherally Inserted Central Line Catheters following Hand and Wrist Infections.

The PearlDiver Patients Records Database was queried to identify patients who underwent treatment for infection of the hand, wrist, and forearm between 2010 and 2018. Logistic regression analysis was utilized to evaluate the association of patient-related risk factors with PICC utilization, complications, readmissions, and length of stay (LOS). A total of 24,665 patients with an upper extremity infection were included in the study. Ultimately, 416 patients required a PICC placement (1.69%). Patients with older age, male gender, certain medical comorbidities, and infection involving deeper structures were more likely to require a PICC. Ninety-day all-cause medical complication rates were significantly higher for the PICC group (19.7% versus 6.7%) compared to those without. Any hospital readmission rates were significantly higher for PICC group at 90 days (28.4% versus 6.3%) and 1 year (35.8% versus 10.9%). Readmission rates remained slightly higher at 1 year for both groups. The PICC group demonstrated significantly longer LOS by 2 days (7.72 days versus 5.14 days). While not required for the majority of hand, wrist, and forearm infections, PICC placement is associated with increased medical complications, more frequent hospital readmissions, and longer LOS.

What's New in Adult Reconstructive Knee Surgery.

What's New in Adult Reconstructive Knee Surgery.

Abstract 14460: Aortic Valve Infective Endocarditis Complicated by Complete Heart Block and Gerbode’s Defect

Introduction: Aortic root abscess with complete heart block is a rare complication of infective endocarditis (IE). Early diagnosis and prompt surgical management are necessary to prevent fatal outcomes. Case Presentation: A 45-year-old male with past medical history of uncontrolled diabetes mellitus was referred to our cardiac intensive care unit for management of complete heart block. His symptoms including exertional dyspnea, hiccups, and dry cough started two weeks prior to presentation. The patient was bradycardic, hypoxic, and hypotensive on examination. Labs were significant for marked leukocytosis 21,000/ul with a neutrophilic predominance. Blood cultures were obtained, and the patient was started on empiric antibiotics vancomycin and piperacillin-tazobactam. Electrocardiogram (ECG) showed evidence of complete heart block and a temporary transvenous pacemaker was placed. A transthoracic echocardiogram was obtained that showed evidence of severe aortic regurgitation and aortic valve vegetations. Due to high clinical suspicion, a transesophageal echocardiogram was immediately performed that revealed aortic root abscess. Patient underwent successful debridement of aortic valve vegetations and aortic valve replacement. Intraoperative findings also included a subaortic left ventricular to right atrial (LV-RA) shunt also known as Gerbode’s defect that was repaired with pericardial patch. Blood cultures and intraoperative tissue cultures confirmed a Staphylococcus lugdunensis infection. He received six weeks of intravenous antibiotics. At 2-month follow-up, the patient reported doing well. Conclusion: New complete heart block may be a manifestation of aortic root abscess. This case illustrates the need to maintain a high level of suspicion for complicated infective endocarditis in patients with sepsis and complete heart block. Timely diagnosis with imaging and early surgical repair results in favorable outcomes.

Long term assessment of antibiotic prophylaxis and biliary microbiome in pancreaticoduodenectomy.

Surgical site infections (SSI) can represent a major complication of pancreaticoduodenectomy (PD). We summarize the outcomes of process improvement efforts to reduce the SSI rates in PD that includes replacing Cefazolin with Ceftriaxone-Metronidazole as antibiotic prophylaxis. Additional efforts included current assessment of biliary microbiome and potential prophylactic failures based on bile cultures and suspected antibiotic allergies. A single-center review of PD patients from January-2012 to March-2021. Study groups were divided into Pre and Post May-2015 (Group 1 and 2, respectively) when Ceftriaxone-Metronidazole prophylaxis and routine intraoperative cultures were standardized. Univariate and multivariable analyses were conducted to assess groups' differences and association with SSI. Six hundred ninety patients identified [267(38.7%) and 423(61.3%) in Group 1 and Group2, respectively]. After antibiotic change, SSI rates decreased from 28.1% to 16.5% (incisional: 17.6%-7.5%, organ-space or abscess: 17.2%-13.0%), Group 1 and Group 2, respectively, P<0.001. Ceftriaxone-Metronidazole was used in 75.9% of patients Group 2. When adjusting for other covariates, an SSI-decrease was associated only with Ceftriaxone-Metronidazole (OR 0.34, P<0.001). Ongoing process improvement has resulted in decreased SSIs with Ceftriaxone-Metronidazole prophylaxis. The benefit of Ceftriaxone-Metronidazole is independent of the biliary microbiome. Improving prophylaxis for those with suspected penicillin allergy is warranted.

Effect of preoperative biliary stent on postoperative complications after pancreaticoduodenectomy for cancer: Neoadjuvant versus upfront treatment

BackgroundLimited data are available regarding the effect of preoperative biliary stent, during long-course neoadjuvant chemotherapy, on postoperative complications. The aim of the study is to analyze whether the association of neoadjuvant chemotherapy and biliary stent increases overall and infectious complications after pancreaticoduodenectomy. MethodsData for 538 consecutive pancreatic ductal adenocarcinoma patients who underwent pancreaticoduodenectomy between 2015 and 2020 were retrospectively analyzed. Four groups of patients were identified: neoadjuvant chemotherapy + biliary stent (171 patients), neoadjuvant chemotherapy–no biliary stent (65 patients), upfront surgery + biliary stent (184 patients), and upfront surgery–no biliary stent (118 patients). Median neoadjuvant chemotherapy duration was 6 months. The main outcome of the study was the occurrence of postoperative infections. ResultsNo differences among the 4 groups were observed for pancreaticoduodenectomy-specific complications (ie, POPF, DGE, PPH). Infectious complications, in particular surgical site infections, were more frequent in neoadjuvant chemotherapy + biliary stent group (P = 0.001). At multivariate analysis, biliary stent was significantly associated with postoperative infectious complications in the overall cohort (odds ratio 1.996, confidence interval 95% 1.29–3.09, P = .002) and in neoadjuvant chemotherapy patients (odds ratio 5.974, 95% confidence interval 2.52–14.13, P < .001). Biliary stent significantly increased the comprehensive complication index by 9.5% (95% confidence interval 0.04–0.64, P = 0.024) in the overall cohort and 18.9% (95% confidence interval 0.22–1.23, P = .005) in the neoadjuvant chemotherapy group. The presence of multidrug-resistant microorganisms in intraoperative bile culture was not influenced by long-course neoadjuvant chemotherapy. ConclusionIn neoadjuvant chemotherapy patients, biliary stent increased the occurrence of postoperative infectious complications and surgical site infections, while the incidence of multidrug-resistant bacteria in intraoperative bile culture was similar between groups.

Reimplantation after Periprosthetic Joint Infection: The Role of Microbiology.

Periprosthetic joint infection (PJI) is among the most feared orthopedic complications. Critical questions are whether the infection is completely resolved before reimplantation and what the clinical significance of positive culture is at reimplantation. The aim of this study was to determine whether a correlation exits between culture results at reimplantation after spacer insertion for hip and knee PJI and treatment failure rate. The data of 84 patients who underwent two-stage exchange arthroplasty for hip or knee PJI were reviewed and the results of intraoperative culture at reimplantation were analyzed quantitatively and qualitatively. Correlations were sought between these patterns and treatment outcome. Our data indicate no evidence for a correlation between positive culture at reimplantation and greater risk of treatment failure. Nonetheless, we noted a higher, albeit statistically not significant rate of treatment failure in patients with at least two samples testing positive. The role of microbiology at reimplantation remains unclear, but a positive culture might signal increased risk for subsequent implant failure. Further studies are needed to elucidate the implications of this finding.

Infection Rate of a Prolonged Sacral Neuromodulation Test: A Large Retrospective Study

ObjectivesIt is estimated that 3.8% to 12.5% of patients develop a device infection during the two to four weeks of the sacral neuromodulation (SNM) test, leading to removal of the entire system. It is possible to prolong the test phase up to the clinician’s decision, particularly when benefits are unclear. The aim of our study is to assess the device infection rate in a prolonged SNM test. Materials and MethodsWe retrospectively enrolled patients who performed a prolonged SNM test (at least eight weeks) in the last five years (2017–2021). All procedures were performed using a standardized technique and the same prophylactic antibiotic protocol. In case of a clinical suspicion of infection, all components were explanted. Patient information (age at implantation, medical history of diabetes, metabolic syndrome, immunologic diseases, or chronic immunosuppressive therapy), surgical data (operative time, intraoperative complications), and infection data (timing of onset, symptoms reported, wound culture results) were recorded. ResultsWe enrolled 232 patients who underwent a prolonged SNM test (mean duration 65.5 days). A local infection that led to the removal of the entire system occurred in six patients (2.6%). The gluteal pocket was always involved, and in two cases, infection was also extended to the exit point of the extension wire. No significant correlations with clinical data were found. Infection occurred beyond four weeks in two cases, between three and four weeks in three cases, and within two weeks in one case. Intraoperative wound culture was performed in five of six patients, and Staphylococcus aureus (S aureus) was isolated in four cases. One culture test gave negative bacterial growth results. ConclusionsThe infection rate of a prolonged eight-week SNM test is low and does not differ from that reported in the literature for a two-to-four–week SNM test. S aureus remains the most frequent bacterium involved.

PROSTHETIC VALVE INFECTIVE ENDOCARDITIS CAUSED BY SERRATIA MARCESCENS IN A PATIENT WITH SURGICAL WOUND INFECTION

PROSTHETIC VALVE INFECTIVE ENDOCARDITIS CAUSED BY SERRATIA MARCESCENS IN A PATIENT WITH SURGICAL WOUND INFECTION

Reliability of Inflammatory Markers as a Diagnostic Tool for Non-Diabetic Foot and Ankle Infections: Case Series Study

Category: Other; Ankle; Basic Sciences/Biologics; Hindfoot; Midfoot/Forefoot; Trauma Introduction/Purpose: The distinction between foot and ankle wound healing complications as opposed to infection is crucial for the appropriate and efficacious allocation of antibiotic therapy. Multiple reports have focused on the diagnostic accuracy of different inflammatory markers, however, mainly in the diabetic population. Our aim was to evaluate the diagnostic accuracy of white cell count (WCC) and C-reactive protein (CRP) as diagnostic tools for this distinction in the non-diabetic cohort. Methods: Data were reviewed from a prospectively maintained Infectious Disease Unit database of 216 patients admitted at Leicester University Hospitals - the United Kingdom with musculoskeletal infections over the period between July 2014 and February 2020 (68 months). All patients with a confirmed diagnosis of diabetes were excluded while only those with a confirmed microbiological or clinical diagnosis of foot or ankle infection were included in our study. For the included patients, we retrospectively retrieved the inflammatory markers (WCCs and CRP) at the time of presentation and during the perioperative period for debridement. Values of CRP 0-10 mg/L and WCC 4.0-11.0 x109 /L were considered normal. Results: After the exclusion of patients with confirmed diabetes, 25 patients with confirmed foot or ankle infections were included. All infections were confirmed microbiologically with positive intra-operative culture results. 7 (28%) patients with osteomyelitis (OM) of the foot, 11 (44%) with OM of the ankle, 5 (20%) with ankle septic arthritis, and 2 (8%) patients with post- surgical wound infection were identified. Previous bony surgery was identified in 52% (n=13), either a corrective osteotomy or an open reduction and internal fixation (ORIF) for a foot or ankle fracture with the infection developing on top of the existing metalwork. 84% (n=21) did have raised inflammatory markers while 16% (n=4) failed to mount an inflammatory response even with subsequent debridement and removal of metalwork. CRP sensitivity was 84%, while WCC sensitivity was only 28%. Conclusion: CRP has relatively good sensitivity in the diagnosis of foot and ankle infections in non-diabetic patients, whereas WCC is a poor inflammatory marker in the detection of such cases. In presence of a clinically high level of suspicion of foot or ankle infection, a normal CRP should not rule out the diagnosis of OM.

An evidence-based approach to managing unexpected positive cultures in shoulder arthroplasty.

Unexpected positive cultures (UPCs) are very commonly found during shoulder arthroplasty when surgeons send intraoperative cultures to rule out periprosthetic joint infection (PJI) without clinical or radiographic signs of infection. Cutibacterium acnes is thought to be the most common bacteria cultured in this setting; however, the implications of an unexpected positive result are neither well defined nor agreed upon within the literature. The current review evaluates the incidence of UPCs and C acnes in reverse total arthroplasty; the clinical significance, if any, of these cultures; and various prognostic factors that may affect UPC incidence or recovery following PJI. A systematic review was performed with PRISMA guidelines using PubMed, CINAHL, and Scopus databases. Inclusion criteria included studies published from January 1, 2000, to May 20, 2021, that specifically reported on UPCs, native or revision shoulder surgery, and any study that directly addressed one of our 6 proposed clinical questions. Two independent investigators initially screened 267 articles for further evaluation. Data on study design, UPC rate/speciation, UPC risk factors, and UPC outcomes were analyzed and described. A total of 22 studies met the inclusion criteria for this study. There was a pooled rate of 27.5% (653/2373) deep UPC specimen positivity, and C acnes represented 76.4% (499/653) of these positive specimens. Inanimate specimen positivity was reported at a pooled rate of 20.1% (29/144) across 3 studies. Male patients were more likely to have a UPC; however, the significance of prior surgery, surgical approach, and type of surgery conflicted across multiple articles. Patient-reported outcomes and reoperation rates did not differ between positive-UPC and negative-UPC patients. The utilization of antibiotics and treatment regimen varied across studies; however, the reinfection rates following surgery did not statistically differ based on the inclusion of antibiotics. UPCs are a frequent finding during shoulder surgery and C acnes represents the highest percentage of cultured bacteria. Various preoperative risk factors, surgical techniques, and postoperative treatment regimens did not significantly affect the incidence of UPCs as well as the clinical outcomes for UPC vs. non-UPC patients. A standardized protocol for treatment and follow-up would decrease physician uncertainty when faced with a UPC from shoulder surgery. Given the results of this review, shoulder surgeons can consider not drastically altering the postoperative clinical course in the setting of UPC with no other evidence of PJI.