Stroke History and Time Elapsed are Predictors of Complications in Total Knee Arthroplasty

BACKGROUND

A consensus has not been reached regarding the optimal timing of elective total knee arthroplasty (TKA) following a stroke. The purpose of this study was to examine the optimal period between stroke and TKA to minimize complications. Specifically, we assessed: (1) medical and surgical complications; (2) timing of stroke and TKA; (3) associated risk factors.

METHODS

A national database identified 69,815 TKA patients that were separated into 6 exclusive cohorts using a stratum likelihood ratio: no stroke (n = 20,000), stroke within 6 (n = 17,764), 12 (n = 10,338), 18 (n = 8,370), 24 (n = 7,121), and 30 months (n = 6,222) prior to TKA. We analyzed 90-day, 1-year, and 2-year complications in each subgroup. Multivariate analyses were used to identify risk factors for periprosthetic joint infection (PJI).

RESULTS

The multivariate regression model identified that patients with a stroke within 6 months of TKA had increased risk of PJI at all time points (P < .001). Also, stroke 12 to 18 months before TKA elevated PJI risk at 1 and 2 years (all P < .021), while those over 18 months did not show a significant risk compared to controls (P > .067).

CONCLUSIONS

Stroke prior to TKA was associated with an increased risk of postoperative complications, specifically PJI. We recommend a minimum of 6 months between stroke and TKA, with 18 months offering the lowest risk.

Effect of Taiwan's Diabetes Shared Care Program on the risk of periprosthetic joint infection after total joint arthroplasty in patients with type 2 diabetes mellitus: an eight-year population-based study

BACKGROUND

Periprosthetic joint infection (PJI) is a significant post-arthroplasty complication for diabetic patients, with uncontrolled diabetes identified as a PJI risk factor. Taiwan's Diabetes Shared Care Program (DSCP) was established for holistic diabetes care.

AIM

To evaluate the DSCP's impact on PJI incidence and patients' medical costs.

METHODS

Data were analysed from Taiwan's National Health Insurance Research Database from 2010 to 2020, focusing on type 2 diabetes mellitus (DM) patients who had undergone arthroplasty. The study group involved DSCP participants, while a comparison group comprised non-participants with matched propensity scores for age, sex, and comorbidities. The primary outcome was the PJI incidence difference between the groups; the secondary outcome was the medical expense difference.

FINDINGS

The study group consisted of 11,908 type 2 DM patients who had arthroplasty and joined the DSCP; PJI occurred in 128 patients. Among non-participants, 184 patients had PJI. The PJI incidence difference between the groups was statistically significant (1.07% vs 1.55%). The study group's medical costs were notably lower, regardless of PJI incidence. Multivariate regression showed higher PJI risk in patients in comparison group, aged >70 years, male, or who had obesity, anaemia.

CONCLUSION

The study indicates that DSCP involvement reduces PJI risks and decreases annual medical costs for diabetic patients after arthroplasty. Consequently, the DSCP is a recommendable option for such patients who are preparing for total joint arthroplasty.

Systemic Inflammatory Response Syndrome and Prosthetic Joint Infection

BACKGROUND

The development of systemic inflammatory response syndrome (SIRS) criteria leads to increased mortality. Little is known about development of SIRS in patients who have prosthetic joint infection (PJI). We aimed to determine the incidence, risk factors, clinical outcomes, and causative organisms in patients who develop SIRS with PJI.

METHODS

We retrospectively identified 655 patients (321 men, 334 women; 382 total hip, 273 total knee) who have hip or knee PJI at 1 institution between July 1, 2015 and December 31, 2020. We formed 2 groups: patients who have SIRS alert (PJI + SIRS) and patients who do not have SIRS alert (PJI). We analyzed clinical outcomes, comorbidities, and operating room culture results.

RESULTS

Of 655 patients, 63 developed SIRS with PJI (9.6%). Intensive care unit (ICU) admission rates (27.0 versus. 6.9%, P < .001) and length of stay (7.7 versus. 5.6 days, P = .003) were greater in PJI + SIRS. At 2 years, reoperation (36.5 versus. 22.3%, P = .01) and mortality rates (17.5 versus. 8.8%, P = .03) were greater in PJI + SIRS. Risk factors included deficiency anemia (P = .001), blood loss anemia (P = .013), uncomplicated diabetes (P = .006), diabetes with complication (P = .001), electrolyte disorder (P < .00001), neurological disorder (P = .0001), paralysis (P = .026), renal failure (P = .005), and peptic ulcer disease (P = .004). Staphylococcus aureus more commonly speciated on tissue cultures in PJI + SIRS (P = .002).

CONCLUSION

The incidence of SIRS is 10% among patients who have PJI. Development of PJI + SIRS is associated with increased lengths of stay, ICU admissions, and 2-year reoperation and mortality rates. Identifying certain comorbidities can stratify patients' risk of developing PJI + SIRS.

History of Diabetic Foot Ulcer is Associated With Increased Risk of Prosthetic Joint Infection and Sepsis After Total Joint Arthroplasty

BACKGROUND

Diabetic foot ulcers (DFUs) are common sequelae of diabetes mellitus. Currently, the effect of DFUs on total joint arthroplasty (TJA) outcomes is sparsely evaluated. This study investigated whether DFU patients undergoing TJA increases risk of (1) prosthetic joint infections (PJI), (2) surgical site infections (SSI), (3) sepsis, (4) readmissions, and (5) revisions.

METHODS

Using PearlDiver, a retrospective query from January 1, 2010 to October 31, 2020 was performed. DFU patients undergoing total knee arthroplasty (TKA) and total hip arthroplasty (THA) were included and 1:5 propensity score matched with controls using age, sex, body mass index, and various comorbidities (33,155 TKA patients [DFU = 5,529; control = 27,626]; 17,146 THA patients [DFU = 2,862; control = 14,284]). Outcomes included rates of PJI, SSI, sepsis, readmissions, and revisions. Multivariate logistical regressions calculated odds ratios (ORs), 95% confidence intervals, and P values (P < .001 as significance threshold).

RESULTS

DFU increased risk of sepsis within 90 days of TKA (OR 4.59; P < .001) and THA (OR 4.87; P < .001). DFU did not increase risk of PJI at 90 days for TKA (OR 0.8; P = .1) or THA (OR 0.85; P = .34) but did by 2 years post-TKA (OR 1.51; P < .001) and THA (OR 1.55; P < .001). Risk of SSI increased in DFU cohort following TKA and THA at 90 days and 2 years and at 90-day readmissions and 2-year revisions.

CONCLUSION

DFU patients undergoing TJA demonstrated increased risk of postoperative sepsis and PJI. Furthermore, DFU patients demonstrated an increased risk of SSI, readmissions, and revisions. Providers should counsel DFU patients about postoperative risks.

Diagnostic benefits of 18F-FDG PET/CT in cases of prosthetic infective endocarditis

Infective endocarditis (IE) is a difficult-to-diagnose provocative disease that causes significant morbidity and mortality. The first-line imaging test for the diagnosis of IE is echocardiography. However, in cases of prosthetic IE or IE associated with intracardiac devices, its sensitivity is limited. A new diagnostic tool, 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET/CT), improves diagnosis in these difficult cases. The most recent European guidelines for IE (2015) include this imaging modality as a primary diagnostic criterion. We present a case of culture-negative prosthetic IE diagnosed with 18F-FDG PET/CT.

Visceral Fat as a Risk Factor for Periprosthetic Joint Infection After Total Hip and Knee Arthroplasty

BACKGROUND

Visceral obesity, a strong indicator of chronic inflammation and impaired metabolic health, has been shown to be associated with poor postoperative outcomes and complications. This study aimed to evaluate the relationship between visceral fat area (VFA) and periprosthetic joint infection (PJI) in total joint arthroplasty (TJA) patients.

METHODS

A retrospective study of 484 patients who had undergone a total hip or knee arthroplasty was performed. All patients had a computed tomography scan of the abdomen/pelvis within two years of their TJA. Body composition data (ie, VFA, subcutaneous fat area, and skeletal muscle area) were calculated at the Lumbar-3 vertebral level via two fully automated and externally validated machine learning algorithms. A multivariable logistic model was created to determine the relationship between VFA and PJI, while accounting for other PJI risk factors. Of the 484 patients, 31 (6.4%) had a PJI complication.

RESULTS

The rate of PJI among patients with VFA in the top quartile (> 264.1 cm2) versus bottom quartile (< 82.6 cm2) was 5.6% versus 10.6% and 18.8% versus 2.7% in the total hip arthroplasty and total knee arthroplasty cohorts, respectively. In the multivariate model, total knee arthroplasty patients with a VFA in the top quartile had a 30.5 times greater risk of PJI than those in the bottom quartile of VFA (P = .0154).

CONCLUSION

VFA may have a strong association with PJI in TJA patients. Using a standardized imaging modality like computed tomography scans to calculate VFA can be a valuable tool for surgeons when assessing risk of PJI.

Super-obese patients are associated with significant infection burden after total hip arthroplasty

INTRODUCTION

Over ⅓ of the population in the United State is obese (body mass index [BMI] >30 kg/m2), with an increasing proportion being morbidly obese (BMI >40 kg/m2). As the obesity rate climbs, an increasing number have entered the super-obese category (BMI >50 kg/m2), theoretically increasing risk for complications after total hip arthroplasty (THA). This study compared complications in non-obese, obese, morbidly obese, and super-obese patients undergoing THA. We specifically assessed: (1) 1- and 2-year peri-prosthetic joint infection (PJI) rates; (2) complication rates; as well as (3) 1- and 2-year revision rates.

METHODS

A database review identified patients undergoing primary THA from 01 January 2010 to 31 December 2019. Patients were stratified based on the presence of International Classification of Diseases, 9th and 10th revision diagnosis codes of non-obese (BMI <30 kg/m2) (n = 8680), obese (BMI <40 kg/m2) (n = 12,443), morbidly obese (BMI <50 kg/m2) (n = 5250), and super-obese (BMI >50 kg/m2) (n = 814) prior to THA. Complication rates at 90 days, 1 year, and 2 years were compared across groups.

RESULTS

At all time points, super-obese patients were associated with higher rates of PJI, even when compared to morbidly obese patients. Complications such as sepsis, venous thrombo-embolism, and revision surgeries were found in higher numbers in super-obese as well as morbidly obese patients, compared to obese and non-obese patients.

CONCLUSIONS

This study provides large-scale analyses demonstrating the association between super-obese and morbidly obese patients and higher infection rates, as well as complications, following THA. Importantly, the association of PJI is highest among super-obese patients, even when compared to morbidly obese patients. Attaining a BMI <40 kg/m2 prior to surgery may be an important goal discussed with patients to lower the chance of postoperative infections.

Does Prednisone Dose Affect Rates of Periprosthetic Joint Infection Following Primary Total Hip and Total Knee Arthroplasty?

BACKGROUND

Prednisone use is associated with higher rates of periprosthetic joint infection (PJI) following total joint arthroplasty (TJA). However, the relationship between prednisone dosage and infection risk is ill-defined. Therefore, this study aimed to assess the relationship between prednisone dosage and rates of PJI following TJA.

METHODS

A national database was queried for all elective total hip (THA) and total knee arthroplasty (TKA) patients between 2015 and 2020. Patients who received oral prednisone following TJA were matched in a 1:2 ratio based on age and sex to patients who did not. Univariate and multivariate regression analyses were performed to assess the 90-day risk of infectious complications based on prednisone dosage as follows: 0 to 5, 6 to 10, 11 to 20, 21 to 30, and >30 milligrams. Overall, 1,322,043 patients underwent elective TJA (35.9% THA, 64.1% TKA). Of these, 14,585 (1.1%) received prednisone and were matched to 29,170 patients who did not.

RESULTS

After controlling for confounders, TKA patients taking prednisone were at increased risk for sepsis (adjusted odds ratio [aOR] 2.76, P < .001), PJI (aOR 2.67, P < .001), and surgical site infection (aOR: 2.56, P = .035). THA patients taking prednisone were at increased risk for sepsis (aOR: 3.21, P < .001) and PJI (aOR: 1.73, P = .001). No dose-dependent relationship between prednisone and infectious complications was identified when TJA was assessed in aggregate.

CONCLUSION

Patients receiving prednisone following TJA were at increased risk of PJI and sepsis. A dose-dependent relationship between prednisone and infectious complications was not identified. Arthroplasty surgeons should be aware of these risks and counsel TJA patients who receive prednisone therapy.

Rates and Outcomes of Periprosthetic Joint Infection in Persons Who Inject Drugs

BACKGROUND

The risk of periprosthetic joint infection (PJI) is higher in persons who inject drugs (PWID) after total joint arthroplasty (TJA), though reported rates vary widely. This study was designed to assess outcomes of TJA in PWID and to describe factors associated with improved PJI outcomes among PWID.

METHODS

A retrospective matched cohort study was performed using a 1:4 match among those with and those without a history of injection drug use (IDU) undergoing TJA. Demographic, surgical, and outcome variables were compared in multivariate logistic regressions to determine PJI predictors. Kaplan-Meier analyses were constructed to characterize the difference in survival of patients who did not have PJI or undergo joint explantation between PWID and the matching cohort.

RESULTS

PWID had a 9-fold increased risk of PJI compared to the matched cohort (odds ratio 9.605, 95% CI 2.781-33.175, P < .001). Ten of 17 PWID whose last use was within 6 months (active use) of primary TJA had a PJI, while 7 of 41 PWID who did not have active use developed a PJI. Of PWID with PJI, treatment failure was seen in 15 of 17, while in patients who did not have an IDU history, 5 of 8 with PJI had treatment failure.

CONCLUSION

IDU is a significant risk factor for PJI following TJA. Future work investigating the effect of a multidisciplinary support team to assist in cessation of IDU and to provide social support may improve outcomes and reduce morbidity in this vulnerable population.

Moderate-to-Severe Malnutrition Identified by the Controlling Nutritional Status (CONUT) Score Is Significantly Associated with Treatment Failure of Periprosthetic Joint Infection

The prevalence and role of malnutrition in periprosthetic joint infection (PJI) remain unclear. This study aimed to use measurable nutritional screening tools to assess the prevalence of malnutrition in PJI patients during two-stage exchange arthroplasty and to explore the association between malnutrition and treatment failure. Our study retrospectively included 183 PJI cases who underwent 1st stage exchange arthroplasty and had available nutritional parameters, of which 167 proceeded with 2nd stage reimplantation. The recently proposed Musculoskeletal Infection Society (MSIS) Outcome Reporting Tool was used to determine clinical outcomes. The Controlling Nutritional Status (CONUT), Nutritional Risk Index (NRI), and Naples Prognostic Score (NPS) were used to identify malnutrition at 1st and 2nd stage exchange, respectively. Multivariate logistic regression analyses were performed to determine the association between malnutrition and treatment failure. Restricted cubic spline models were further used to explore the dose−response association. Additionally, risk factors for moderate-to-severe malnutrition were evaluated. Malnourished patients identified by CONUT, NPS, and NRI accounted for 48.1% (88/183), 98.9% (181/183), and 55.7% (102/183) of patients at 1st stage, and 9.0% (15/167), 41.9% (70/167), and 43.1% (72/167) at 2nd stage, indicating a significant improvement in nutritional status. We found that poorer nutritional status was a predictor of treatment failure, with CONUT performing best as a predictive tool. Moderate-to-severe malnutrition at 1st stage identified by CONUT was significantly related to treatment failure directly caused by PJI (odds ratio [OR] = 5.86), while the OR was raised to 12.15 at 2nd stage (OR = 12.15). The linear dose−response associations between them were also confirmed (P for nonlinearity at both 1st and 2nd stage > 0.05). As for total treatment failure, moderate-to-severe malnutrition as determined by CONUT was associated with a 1.96-fold and 8.99-fold elevated risk at the 1st and 2nd stages, respectively. Age ≥ 68 years (OR = 5.35) and an increased number of previous surgeries (OR = 2.04) may be risk factors for moderate-to-severe malnutrition. Overall, the prevalence of malnutrition in PJI patients is very high. Given the strong association between moderate-to-severe malnutrition identified by CONUT and PJI treatment failure, COUNT could be a promising tool to evaluate the nutritional status of PJI patients to optimize treatment outcomes.

Periprosthetic joint infection rates across primary total hip arthroplasty surgical approaches: a systematic review and meta-analysis of 653,633 procedures

INTRODUCTION

Evidence demonstrates comparable clinical outcomes across the various surgical approaches to primary total hip arthroplasty (THA). However, high-quality contemporary data regarding periprosthetic joint infection (PJI) risk between direct anterior approach (DAA) and other (THA) approaches is lacking. This systematic review and meta-analysis evaluated PJI rates reported in the literature between the DAA and other approaches.

MATERIALS AND METHODS

Five online databases were queried for all studies published from January 1st, 2000 through February 17th, 2021 that reported PJI rates between DAA and other surgical approaches. Studies reporting on primary THAs for osteoarthritis (OA) and that included PJI rates segregated by surgical approach were included. Articles reporting on revision THA, alternative THA etiologies, or minimally invasive techniques were excluded. Mantel-Haenszel (M-H) models were utilized to evaluate the pooled effect of surgical approach on infection rates. Validated risk of bias and methodological quality assessment tools were applied to each study. Multiple sensitivity analyses were conducted to evaluate the robustness of analyses.

RESULTS

28 articles reporting on 653,633 primary THAs were included. No differences were found between DAA cohorts and combined other approaches (OR: 0.95; 95% CI 0.74-1.21; p = 0.67) as well as segregated anterolateral approach cohorts (OR: 0.82, 95% CI 0.64-1.06; p = 0.13). However, DAA patients had a significantly reduced risk of infection compared to those undergoing posterior (OR: 0.66, 95% CI 0.58-0.74; p < 0.0001) and direct lateral (OR: 0.56, 95% CI 0.48-0.65; p < 0.00001) approaches.

CONCLUSION

The DAA to primary THA had comparable or lower PJI risk when compared to other contemporary approaches. The results of the most up-to-date evidence available serve to encourage adult reconstruction surgeons who have already adopted the DAA. Additionally, orthopaedic surgeons considering adoption or use of the direct anterior approach for other reasons should not be dissuaded over theoretical concern for a general increase in the risk of PJI.

LEVEL OF EVIDENCE

Level III.

Does Surgical Approach for Total Hip Arthroplasty Impact Infection Risk in the Obese Patient? A Systematic Review

This systematic review evaluated the combined effects of obesity and surgical approach on periprosthetic joint infection (PJI) rates after total hip arthroplasty (THA). Wound complication and PJI rates were elevated among patients with body mass index (BMI) of 30 kg/m2 or greater and 35 kg/m2 or greater, respectively, with the direct anterior approach (DAA). A BMI of 30 kg/m2 or greater also increased the risk of PJI with the posterior approach. Patients with BMI of 30 kg/m2 or greater undergoing anterolateral approach THA did not have increased risk of PJI. Patients with elevated BMI (≥30 kg/m2) are at risk for PJI, regardless of approach. Patients undergoing DAA THA who have BMI of 35 kg/m2 or greater may have an increased risk of PJI compared with those undergoing THA with other approaches. [Orthopedics. 2022;45(2):e67-e72.].

How to Handle Concomitant Asymptomatic Prosthetic Joints During an Episode of Hematogenous Periprosthetic Joint Infection, a Multicenter Analysis

BACKGROUND

Prosthetic joints are at risk of becoming infected during an episode of bacteremia, especially during Staphylocococcus aureus bacteremia. However, it is unclear how often asymptomatic periprosthetic joint infection (PJI) occurs, and whether additional diagnostics should be considered.

METHODS

In this multicenter study, we retrospectively analyzed a cohort of patients with a late acute (hematogenous) PJI between 2005-2015 who had concomitant prosthetic joints in situ. Patients without at least 1 year of follow-up were excluded.

RESULTS

We included 91 patients with a hematogenous PJI and 108 concomitant prosthetic joints. The incident PJI was most frequently caused by Staphylococcus aureus (43%), followed by streptococci (26%) and Gram-negative rods (18%). Of 108 concomitant prosthetic joints, 13 were symptomatic, of which 10 were subsequently diagnosed as a second PJI. Of the 95 asymptomatic prosthetic joints, 1 PJI developed during the follow-up period and was classified as a "missed" PJI at the time of bacteremia with S. aureus (1.1%). Infected prosthetic joints were younger than the noninfected ones in 67% of cases, and prosthetic knees were affected more often than prosthetic hips (78%).

CONCLUSIONS

During an episode of hematogenous PJI, concomitant asymptomatic prosthetic joints have a very low risk of being infected, and additional diagnostic work-up for these joints is not necessary.

Bias Does Not Exist in Treating Knee Periprosthetic Joint Infection Among Patients With Substance Use Disorder

Debridement, antibiotics with implant retention (DAIR), and 2-stage revision are standard surgical interventions for treating knee periprosthetic joint infection (PJI). Patients with substance use disorder (SUD), especially addictive drug use disorder (DUD), have been shown to receive inferior medical care in many specialties compared with nonusers. The authors identified patients with a diagnosis of PJI after knee arthroplasty who received either DAIR or 2-stage revision with the Nationwide Inpatient Sample (NIS) database from 2010 to 2014. Patients were stratified into 2 groups, patients with DUD and nonusers, based on Diagnostic and Statistical Manual of Mental Disorders, 5th Edition, criteria. Descriptive analysis was conducted to show the national trend for knee PJI treatment among the 2 patient groups. Multivariate logistic regression was used to compare the prevalence of DAIR and 2-stage revision between these 2 groups, adjusted for likely confounders, including age, sex, income, race, and comorbidities. Among the 11,331 patients with knee infection, 139 (1.23%) had DUD. Compared with nonusers, patients with DUD were significantly younger (P<.001), had more chronic conditions (P<.001), and were predominantly in lower income quartiles (P=.046). The 2 groups did not differ in sex and race (P=.072 and P=.091, respectively). The authors found that 30.22% of patients with DUD and 36.36% of nonusers received DAIR. The difference in these proportions was not statistically significant (P=.135). The results did not change after adjustment for confounding factors (P=.509). The findings suggested that bias does not exist among orthopedic surgeons who choose DAIR or 2-stage revision for knee PJI among patients with DUD. [Orthopedics. 2021;44(3):e385-e389.].

Staphylococcus-induced glomerulonephritis: potential role for corticosteroids

Staphylococcus aureus is a troublesome pathogen, responsible for a broad range of clinical manifestations, ranging from benign skin infections to life-threatening conditions such as endocarditis and osteomyelitis. The kidney can be affected through a rapidly progressive glomerulonephritis mediated by an inflammatory reaction against a superantigen deposited in the glomerulus during the infection's course. This glomerulopathy has a poor prognosis, often leading to chronically impaired kidney function, eventually progressing to end-stage renal disease. Treatment rests on antibiotherapy. Despite the inflammatory role in this disease's pathophysiology, most authors discourage a simultaneous immunosuppressive approach given the concomitant infection. However, there are some reports of success after administration of systemic corticosteroids in these patients. We present a 66-year-old man with a staphylococcus-induced glomerulonephritis brought on by a vascular graft infection, with rapidly deteriorating kidney function despite extraction of the infected graft and 3 weeks of antibiotherapy with achievement of infection control. Kidney function improved after the introduction of corticosteroids. This case highlights the potential role of corticosteroids in selected cases of staphylococcus-induced glomerulonephritis, particularly those in which the infection is under control.

Long-Term Impact of Suppressive Antibiotic Therapy on Intestinal Microbiota

The aim was to describe the safety of indefinite administration of antibiotics, the so-called suppressive antibiotic therapy (SAT) and to provide insight into their impact on gut microbiota. 17 patients with SAT were recruited, providing a fecal sample. Bacterial composition was determined by 16S rDNA massive sequencing, and their viability was explored by PCR-DGGE with and without propidium monoazide. Presence of antibiotic multirresistant bacteria was explored through the culture of feces in selective media. High intra-individual variability in the genera distribution regardless of the antibiotic or antibiotic administration ingestion period, with few statistically significant differences detected by Bray-Curtis distance-based principle component analysis, permutational multivariate analysis of variance and linear discriminant analysis effect size analysis. However, the microbiota composition of patients treated with both beta-lactams and sulfonamides clustered by a heat map. Curiously, the detection of antibiotic resistant bacteria was almost anecdotic and CTX-M-15-producing E. coli were detected in two subjects. Our work demonstrates the overall clinical safety of SAT and the low rate of the selection of multidrug-resistant bacteria triggered by this therapy. We also describe the composition of intestinal microbiota under the indefinite use of antibiotics for the first time.

Fungal endocarditis with heart valve replacement and atrial fibrillation posing a treatment challenge: A case report

RATIONALE

Fungal endocarditis (FE) is a rare disease, in which antifungal treatment is necessary. When FE is complicated with prosthetic heart valve and/or atrial fibrillation, the coadministration of antifungal agents and warfarin is inevitable. We report a case of rheumatic heart disease with atrial fibrillation who developed FE following prosthetic heart valve replacement. The international normalized ratio (INR) increased significantly during the antifungal treatment with fluconazole. A discussion of the antifungal strategy in FE patients with prosthetic heart valves and/or atrial fibrillation and the interaction between antifungal agents and warfarin was performed.

PATIENT CONCERNS

A 54-year-old Chinese woman experienced intermittent fevers, aphemia, and weakness in her right extremities. Her temperature was 38.7°C, and there was atrial fibrillation with heart rate 110 times/min. Neurological examination revealed that she had drowsiness, Broca aphasia, right central facial paralysis, and hemiplegia (Medical Research Council scale, upper limb grade 0, lower limb grade II).

DIAGNOSES

Multiple infarction on magnetic resonance imaging and the occlusion of left middle cerebral artery suggested the occurrence of cerebral embolism. The presence of Candida parapsilosis in the results of 4 blood cultures and the existence of valve vegetation in the reexamination of echocardiogram supported the diagnosis of FE.

INTERVENTIONS

The patient was given antifungal therapy with fluconazol. The INR increased dramatically on the 9th day of antifungal treatment, and subcutaneous bruising occurred at the intravenous infusion site. The antagonist of vitamin K1 was used and warfarin was reduced to a smaller dosage. The antifungal agent was replaced with caspofungin.

OUTCOMES

Her speech improved significantly, and the muscle strength of her paralyzed side reached the Medical Research Council scale of grade IV. She continued to receive caspofungin for antifungal treatment with relatively stable INR and waited for heart valve surgery.

LESSONS

The choice of antifungal agents is often a big challenge for FE patients, especially when they need warfarin for anticoagulation. It is better to administer a low dose of warfarin while carefully monitoring the INR or choose the antifungal drugs with little or no effect on warfarin.

Mycobacterium chimaera After Aortic Valve Replacement Causing Aortic Rupture and Prosthetic Valve Endocarditis

A 20-year-old man with severe aortic insufficiency received a mechanical aortic valve replacement. Afterward he subsequently presented with an aortic root dissection, pseudoaneurysm, and prosthetic valve endocarditis requiring surgical reinterventions twice with a positive Mycobacterium chimaera tissue culture despite prolonged antimycobacterial therapy. This is the first reported clinical case of M chimaera in Western Canada and the first with M chimaera-associated aortic dissection and pseudoaneurysm.

Surgical Treatment of Acute Periprosthetic Knee Infection with Concurrent Presumed COVID-19: A Case Report

CASE

We report the case of a 64-year-old man who presented with a late onset of acute periprosthetic joint infection after total knee arthroplasty and a positive severe acute respiratory syndrome coronavirus 2 polymerase chain reaction test. We describe our perioperative protocol and challenges for ensuring the safety of healthcare providers while operating on a coronavirus disease 2019 (COVID-19)-positive patient.

CONCLUSIONS

Given the incredible spread of COVID-19 globally, hospitals should anticipate perioperative protocols for the surgical management of COVID-19-positive patients with concurrent pathology to ensure safety to healthcare providers.

Coronary Drug-Eluting Stent Infection Complicated by Coronary Artery Aneurysm and Purulent Pericarditis: Complete Resolution Without Surgery

Coronary stent infection is considered to be a rare but catastrophic complication of percutaneous coronary intervention. In this report, we present a 72-year-old man who developed a coronary stent infection complicated by coronary aneurysm and purulent pericarditis. Coronary artery aneurysm resolved over a period of 8 months following the successful management of infection with intensive antibiotic therapy alone. This case suggests that conservative therapy can be a therapeutic option in patients with high operative risks.

Incidence and risk factors for heterotopic ossification following periprosthetic joint infection of the hip

INTRODUCTION

Heterotopic ossifications (HOs) commonly occur following total hip arthroplasty. Data regarding the appearance of HO after periprosthetic joint infection (PJI) of the hip are rare. Therefore, the aim of this study was to analyze the incidence and potential risk factors for the development of HO in patients with PJI of the hip.

MATERIALS AND METHODS

We performed a single-center, retrospective study including patients treated with a two- or multistage operation and patients undergoing salvage procedure in cases of PJI of the hip with a minimum follow-up of 6 months. A total of 150 patients were included in the analysis. The Brooker-scale was used to classify HO. Patients were divided in three groups: (1) No HO, (2) HO Brooker type 1-4, and (3) high-grade HO (HO Brooker type 3 and 4). In each group, we checked possible risk factors for the development of HO for statistical significance.

RESULTS

Patients included in our study had a mean age of 70.4 ± 12.1 years. Of all patients, 75 were women (50%). HOs could be found in 70 patients (46.7%). Twenty-seven patients showed HO Brooker type 1, 23 type 2, 15 type 3 and 5 type 4. Male gender [odds ratio (OR) 2.14; p = 0.022], smoking (OR 5.75; p = 0.025) were significant risk factors for HO. A chronic infection (OR 3.54; p = 0.029) and a higher number of procedures (p = 0.009) were significant risk factors for the development of high-grade HO.

CONCLUSIONS

HOs often occur following surgical care of PJI. Male gender, smoking, a chronic infection and high number of operations are risk factors for developing HO after PJI.

Obese patients have higher rates of polymicrobial and Gram-negative early periprosthetic joint infections of the hip than non-obese patients

Background

Obese patients are more likely to develop periprosthetic joint infection (PJI) after primary total joint arthroplasty. This study compared the clinical and microbiological characteristics of non-obese, obese and severely obese patients with early PJI, in order to ultimately optimize antibiotic prophylaxis and other prevention measures for this specific patient category.

Methods

We retrospectively evaluated patients with early PJI of the hip and knee treated with debridement, antibiotics and implant retention (DAIR) between 2006 and 2016 in three Dutch hospitals. Only patients with primary arthroplasties indicated for osteoarthritis were included. Early PJI was defined as an infection that developed within 90 days after index surgery. Obesity was defined as a BMI ≥30kg/m² and severe obesity as a BMI ≥35kg/m².

Results

A total of 237 patients were analyzed, including 64 obese patients (27.0%) and 62 severely obese patients (26.2%). Compared with non-obese patients, obese patients had higher rates of polymicrobial infections (60.3% vs 33.3%, p<0.001) with more often involvement of Enterococcus species (27.0% vs 11.7%, p = 0.003). Moreover, severely obese patients had more Gram-negative infections, especially with Proteus species (12.9% vs 2.3%, p = 0.001). These results were only found in periprosthetic hip infections, comprising Gram-negative PJIs in 34.2% of severely obese patients compared with 24.7% in obese patients and 12.7% in non-obese patients (p = 0.018).

Conclusions

Our results demonstrate that obese patients with early periprosthetic hip infections have higher rates of polymicrobial infections with enterococci and Gram-negative rods, which stresses the importance of improving preventive strategies in this specific patient category, by adjusting antibiotic prophylaxis regimens, improving disinfection strategies and optimizing postoperative wound care.

Implant-related sepsis in lower limb fractures following gunshot injuries in the civilian population: A systematic review

INTRODUCTION

The management of long bone lower limb fractures secondary to gunshot wounds (GSWs) in the civilian setting are complex and there is currently no consensus regarding the optimal approach to managing such fractures. This study aims to address the relationship of implant related sepsis in fractures secondary to GSWs.

METHODS

A systematic review of the literature was performed on both Pubmed and Scopus databases that look at fractures caused by GSWs in the lower limb. A total of 14 studies met the inclusion criteria set in this study.

RESULTS

Current literature suggests that low and high velocity injuries managed with internal fixation, such as intramedullary nails, may carry a low risk of superficial and deep infection, with no obvious risk of osteomyelitis. However, infection was poorly defined across all studies and no study used a validated scoring system for infection making it difficult to draw any valid conclusion on the rate of infection following internal fixation of lower limb fractures following both high and low velocity GSWs.

CONCLUSION

There is no clear evidence to confirm or refute that internal fixation is the ideal method of management in these complex injuries and guidance is needed due to the high and increasing proportion of patients presenting with these complex injuries worldwide.

Pseudomonas stutzeri prosthetic valve endocarditis: A case report and review of the literature

We report a case of Pseudomonas stutzeri endocarditis in Lebanon. The patient had a recent history of prosthetic aortic valve replacement and presented to the emergency department with fever and chills. Transesophageal echocardiography confirmed the presence of a vegetation on the prosthetic valve and blood cultures yielded P. stutzeri. The patient was treated with surgery and antibiotics but deteriorated and passed away four days after admission. To our knowledge, this is the fifth case of P. stutzeri endocarditis reported in the literature, and the first case with early presentation and mortality.

Pseudoaneurysm rupture with hemorrhagic shock in a patient with periprosthetic hip joint infection: A case report

RATIONALE

Although pseudoaneurysm (PA) formation following primary and revision total hip arthroplasty (THA) is rare, PA rupture may lead to severe complications that can result in a threat to life and limb.

PATIENT CONCERNS

A 65-year-old man presented with acute hemorrhagic discharge for one day from the chronic hip sinus secondary to revision THA that had been performed 6 years ago, for which he had received multiple courses of debridement, antibiotics, and implant retention procedures owing to periprosthetic joint infection (PJI).

DIAGNOSES

Radiographs showed septic loosening of both the femoral and acetabular components, with medial migration of the component beyond Kohler's line. Contrast-enhanced computed tomography angiogram of the abdomen and pelvis of the patient demonstrated a large PA of the right external iliac artery (EIA), measuring 6.1 cm × 7.7 cm in diameter and 9.1 cm in length.

INTERVENTIONS

A ball-shaped antibiotic-loaded cement spacer (ALCS) was used to tamponade a bleeding PA, treat the coexisting PJI, and thus facilitate endovascular stent-graft repair (ESGR) later on.

OUTCOMES

The ESGR resulted in complete exclusion of the PA and successfully controlled the bleeding. The patient underwent a successful revision THA 6 months after stent insertion. Neither stent-graft infection nor recurrent PJI were detected at 18 months.

LESSONS

Given the potential of a PA for causing significant morbidity and mortality, the surgeon should have an elevated index of suspicion in the presence of intrapelvic migration of the acetabular component. While facing a PA rupture with/without hemorrhagic shock in patients with coexisting hip PJI, ALCS ball implantation and subsequent ESGR might be an effective method to save the patient's life and limb.

Preoperative Anemia Is Associated With Failure of Open Debridement Polyethylene Exchange in Acute and Acute Hematogenous Prosthetic Joint Infection

BACKGROUND

Acute and acute hematogenous prosthetic joint infections (PJIs) are often treated with open debridement and polyethylene exchange (ODPE) in an effort to save the prosthesis, decrease morbidity, and reduce costs. However, failure of ODPE may compromise a subsequent 2-stage treatment. The purpose of this study is to identify patient factors that impact the success of ODPE for acute and acute hematogenous PJIs.

METHODS

A retrospective review examined comorbidities, preoperative laboratory values, and patient history for patients with successful and failed ODPE treatment for acute perioperative or acute hematogenous periprosthetic hip or knee joint infections. Successful treatment was defined as retaining a well-fixed implant without the need for additional surgery for a minimum of 6-month follow-up with or without lifelong oral maintenance antibiotics.

RESULTS

Fifty-three of 72 patients (73.6%) underwent successful ODPE. Of the 19 failures, 14 completed 2-stage revision with one subsequent known failure for recurrent infection. Patients with a Staphylococcus aureus infection were more likely to fail ODPE (48.3% vs 11.6%, P = .0012, odds ratio 7.1, 95% confidence interval 2.3-25.3). Patients with a preoperative hematocrit ≤32.1 were also more likely to fail ODPE (55% vs 16%, P = .0013, odds ratio 6.7, 95% confidence interval 2.2-22.4). When neither risk factor was present, 97.1% of PJIs were successfully treated with ODPE.

CONCLUSION

S aureus infection and preoperative hematocrit ≤32.1 are independent risk factors for ODPE failure. ODPE is a safe alternative to 2-stage revision in patients without preoperative anemia and without S aureus infection. Two-thirds of patients with a failed ODPE were successfully treated with a 2-stage reimplantation.

Panophthalmitis caused by Streptococcus dysgalactiae subsp. equisimilis: A case report and literature review

Lancefield group G β-hemolytic Streptococcus dysgalactiae subspecies equisimilis (SDSE) has become a leading causative pathogen of invasive streptococcal infection. In this report, we describe a case of disseminated SDSE infection complicated by endogenous endophthalmitis, resulting in panophthalmitis and blindness. A 65-year-old man who underwent mitral valve replacement surgery two months previously was hospitalized due to high fever and right visual loss. A systemic investigation revealed endophthalmitis complicated by mediastinal abscess, prosthetic infective endocarditis, cerebral emboli and hemorrhage, and multiple arthritis. The patient underwent various surgeries, including vitrectomy, mediastinal lavage, mitral valve replacements, joint lavages, as well as an intensive antibiotic treatment. His general condition gradually improved, but the ocular infection developed to panophthalmitis, which ultimately required ophthalmectomy. A literature review regarding Group G-associated endogenous endophthalmitis suggested that the disease occurs in elderly people, is frequently complicated with endocarditis, and yields poor visual prognosis regardless of appropriate antibiotic treatment and surgical therapies. In this aging society, invasive infections with SDSE should be much more recognized among medical practitioners in order to improve patient prognosis.

[Lead-related infective endocarditis with massive vegetation causing severe functionnal tricuspid stenosis]

Lead-related infective endocarditis with negative hemocultures constitutes a severe condition potentially associated with a pejorative prognosis. It may induce a functional tricuspid stenosis caused by an important obstructive vegetation. We report the case of an 82 year-old woman in whom the lead-related endocarditis produced massive vegetation causing a severe functional tricuspid stenosis. We describe the medical history, diagnosis and treatment.

Is There a Threshold Value of Hemoglobin A1c That Predicts Risk of Infection Following Primary Total Hip Arthroplasty?

BACKGROUND

There remains little evidence to support a perioperative hemoglobin A1c (HbA_1c) level that could serve as a threshold for a significantly increased risk of deep postoperative infection in patients with diabetes mellitus (DM) following total hip arthroplasty (THA).

METHODS

A national administrative database was queried for patients who underwent primary THA with DM. Patients with an HbA_1c level within 3 months of surgery were identified and were stratified based on HbA_1c level in 0.5 mg/dL increments. The incidence of deep infection requiring operative intervention within 1 year for each group was identified and a receiver operating characteristic (ROC) and area under the curve (AUC) analysis was performed to determine a threshold value of the HbA_1c.

RESULTS

A total of 7736 patients who underwent THA with a perioperative HbA_1c level were included. The rate of infection ranged from 0.7% to 5.9%. The inflection point of the ROC curve corresponded to an HbA_1c level between 7.0 and 7.5 mg/dL (P = .001, specificity = 69%, sensitivity = 47%). The AUC for the ROC was 0.68. Patients with an HbA_1c level of 7.5 mg/dL or greater had a significantly higher risk of deep infection compared to patients below this threshold (odds ratio, 2.6; 95% CI, 1.9-3.4; P < .0001).

CONCLUSION

The risk of infection in patients with DM increases as the perioperative HbA_1c increases. However, in the present study, the HbA_1c threshold level calculated demonstrated low discrimination based on our AUC value, suggesting the HbA_1c test is poorly predictive of periprosthetic joint infection following THA in patients with DM.

Use of Articulating Spacer Technique in Revision Total Knee Arthroplasty Complicated by Sepsis: A Systematic Meta-Analysis

Periprosthetic infection after total knee arthroplasty is a devastating complication, and 2-stage exchange is the standard of care in North America. Articulating spacers are effective in treating periprosthetic joint infections, but the optimal articulating spacer construct has yet to be identified. The authors performed a systematic review using MEDLINE, MEDLINE In-Process, EMBASE, BIOSIS, ClinicalTrials.gov, and Cochrane Database of Systematic Reviews. They identified 34 articles meeting inclusion criteria, producing 1016 spacers for comparison. Metal-on-polyethylene spacers had a statistically significant increased interim range of motion compared with other spacers (P<.003). No statistical differences regarding reinfection rates existed among the 4 types of articulating spacers (P<.68). Difficulty of reimplantation was similar between groups (P<.10). There were fewer spacer-specific complications with the metal on polyethylene compared with the other groups (P<.043) and no spacer fractures. This study answers several clinically relevant questions and provides useful information in guiding clinical decision making in treating periprosthetic infections after total knee arthroplasty. [Orthopedics. 2017; 40(4):212-220.].

Valve Dehiscence after Bentall Procedure: The Detrimental Traits of Propionibacterium

The present case exemplified the detrimental traits of prosthetic valve endocarditis caused by Propionibacterium acnes. As a baby, the patient had a congenital cardiac defect with truncus arteriosus type I with interrupted aortic arch and open ductus Botalli, and had undergone several operations. However, at 18 months after a Bentall procedure performed 29 years later he presented with major prosthetic dehiscence due to endocarditis. The patient underwent a high-risk reoperation for a re-do Bentall procedure and was treated postoperatively with intravenous antibiotics consisting of vancomycin for five weeks and penicillin and rifampicin each for six weeks. He was discharged from hospital in good clinical condition. In conclusion, P. acnes-mediated endocarditis of a prosthetic valve can be successfully treated with prompt surgery and antibiotic therapy.

Successful management of a giant unruptured mycotic coronary artery aneurysm after coronary angioplasty

Coronary artery stent infection has been reported with both bare metal stent and drug eluting stent and can present as mycotic coronary artery aneurysm, pseudoaneurysm, myocardial abscess, pericarditis or exudative effusion. Infection at the site of coronary stent implantation is rare and is believed to result typically from either direct stent contamination at the time of delivery or transient bacteraemia from access site. Introduction of drug-eluting stent (DES) has led to a marked reduction in the problem of in-stent restenosis across all patient subsets and lesions complexities. Recently, several case reports of pseudoaneurysm formation after DES implantation have been reported in the literature. We describe the successful surgical management of giant mycotic pseudoaneurysm of left anterior descending artery (LAD) presenting as fever of unknown origin. This report illustrates the importance of early detection and prompt management of these rare coronary pseudoaneurysms, which is a highly lethal condition.

Diagnosing Infection in the Setting of Periprosthetic Fractures

BACKGROUND

The diagnosis of periprosthetic joint infection is particularly challenging in patients with periprosthetic fractures. The purpose of this study was to investigate the utility of commonly used diagnostic tests for periprosthetic joint infection in patients with a periprosthetic fracture.

METHODS

Of 121 patients treated with a periprosthetic fracture (97 hips, 24 knees, mean age: 72.9), 14 (11.6%) met Musculoskeletal Infection Society criteria for infection. Diagnostic variables were evaluated using logistic regression models for the prediction of infection and receiver operating characteristics curves.

RESULTS

The synovial white blood cell (WBC) count and differential were the best diagnostic tests, with good test performance (area under the curve, 84%) and optimal cutoffs of 2707 WBC/uL and 77% polymorphonuclear cells. The erythrocyte sedimentation rate and C-reactive protein were found to have overall lower test performance but remained relatively sensitive at standard cutoff values of 30 mm/h and 10 mg/L, respectively.

CONCLUSION

The synovial fluid WBC count and differential are the best tests with optimal cutoff values that are similar to those used for patients without a periprosthetic fracture.

CT-Guided aspiration biopsy of infected aortic graft in a patient with hypertrophic osteoarthropathy: Saline injection to improve diagnostic yield - A case report

Unilateral hypertrophic osteoarthropathy can be a diagnostic clue to chronic infection of an aortic graft and aorto-enteric fistula. In a 62-year-old woman, non-invasive diagnostic procedures failed to prove the infection. CT-guided fine needle biopsy revealed the pathogens prompting re-intervention. The biopsy result was markedly improved by injecting physiologic saline into the perigraft tissue.

Analysis of Recurrent Mitral Regurgitation after Mitral Valve Repair

Mitral valve repair was performed in 437 patients with mitral regurgitation from January 1994 to January 2002. The causes of mitral regurgitation were degenerative in 238 (54%), rheumatic in 134 (31%), and others in 65 (15%). The most frequently employed surgical techniques were ring annuloplasty in 417 (95%) cases, new chordae formation in 216 (50%), and quadrangular resection in 117 (27%). The mean follow-up was 29.04 ± 22.81 months. There were 5 (1.2%) early and 5 (1.2%) late deaths. The reoperation rate was 1.6% with 41 (9%) cases of recurrent mitral regurgitation. Of these 22 were procedure-related: incomplete repair in 13, discordant new chordal length in 7, suture dehiscence and leaflet perforation in 1 case each. There were 19 cases of valve related failures: progression of rheumatic disease in 18 and subacute infective endocarditis in 1. Valve-related failure strongly correlated with progression of rheumatic disease. As initial operative success was the prime determinant of repair durability, intraoperative repair assessment with transesophageal echocardiography was essential.

False Anastomotic Aneurysms

This retrospective study covers the period from 1991 to 2002, during which 3,623 patients were operated on because of aneurysmal or occlusive disease of aortoiliac and femoropopliteal segments. Among them, 87 patients (2.4%) developed a false anastomotic aneurysm in the 12-year follow-up period and were treated operatively.

Most frequently, in 53 patients (6.9%), a false anastomotic aneurysm developed after aortobifemoral bypass performed owing to aortoiliac occlusive disease. The cause of false anastomotic aneurysm was infection in 21 cases (24.7%); resection and revascularization were performed with a Dacron graft in 46 cases (52.9%), with a polytetrafluoroethylene graft in 10 cases (11.5%), and with the great saphenous vein in 16 cases (18.4%). Homograft implantation in 4 patients (4.6%) or extra-anatomic bypasses in 11 cases (12.6%) were performed when graft infection was suspected. Of 87 patients who underwent surgery, 74 (85.5%) had good early results without infection, reintervention, limb loss, and mortality.

The presence of infection as a cause of false anastomotic aneurysm and comorbidity increased the mortality rate significantly after the reoperation, whereas the type of graft used in treatment had no influence on early results.

[EFFECT OF INFECTION ON CAPSULE FORMATION AFTER BREAST IMPLANTS]

OBJECTIVE

To investigate the correlation between infection and capsular contracture by observing the effect of infection on the formation of the surrounding capsule after breast implants.

METHODS

Three healthy adult female Diannan small-ear pigs underwent augmentation mammaplasty using miniature implants, which were randomly divided into group A (12 nipples), group B (10 nipples), and group C (12 nipples). Staphylococcus epidermidis (SE ATCC12228 and SE RP62A, 1.2 x 10⁵ CFU/mL) was inoculated into the periprosthetics of groups B and C, and sterile PBS in group A before breast implants. Then the silica gel prosthesis was put, total 34 implants in 3 groups. After 13 weeks, the capsule was harvested to measure the capsular tension and weight. HE staining was used to observe the structure characteristics of the capsule and to measure the capsule thickness, Van-Gieson (VG) staining to observe the capsule collagen characteristics, and α-smooth muscle actin (α-SMA) immunocytochemistry staining to observe myofibroblasts in capsule.

RESULTS

Primary healing of incision was obtained, and 3 small-ear pigs showed stable life indication. The complete fibrous capsule was observed after 13 weeks in 3 groups. Capsule tension showed no significant difference among 3 groups (P > 0.05). Capsule weight was significantly greater in group C than in groups A and B (P < 0.05). HE staining showed that capsule structure of the 3 groups was similar with obvious dense layer and loose layer, and the capsule thickness was also significantly greater in group C than in groups A and B (P < 0.05), but no significant difference was found between groups A and B (P > 0.05). VG staining showed that collagenous fiber in the capsule were more compact in group C than in groups A and B. The α-SMA immunocytochemistry staining indicated the myofibroblasts in capsule were the most in group C.

CONCLUSION

Infection after breast implants has obvious impacts on the formation of the capsule, and there was a causal link between infection and capsular contracture.

Acute Onset of Vancomycin Anaphylaxis With Disseminated Intravascular Coagulation in an Orthopedic Patient Despite Prior Repeated Exposure

Vancomycin is a glycopeptide antibiotic that exhibits bactericidal activity against gram-positive cocci. It is commonly recommended for surgical prophylaxis in cases of suspected bacterial resistance or penicillin allergy. There are 2 main types of hypersensitivity reactions associated with vancomycin. Red man syndrome is an anaphylactoid reaction caused by direct release of histamine. The second is an anaphylactic reaction, which is an immunoglobulin E-mediated response. We present the case of a 55-year-old woman with a history of metastatic giant cell tumor of the right proximal tibia. She had undergone multiple surgeries for this and other nonorthopedic conditions. The patient received vancomycin for the majority of these procedures and extended courses of vancomycin on 2 separate occasions. In the present case, the patient was taken to the operating room for a prosthetic infection, and vancomycin was given after cultures were taken. The patient immediately developed signs consistent with anaphylaxis and disseminated intravascular coagulation. This was treated acutely with hemodynamic resuscitation, replacement of blood components, steroids, and repeated boluses of epinephrine. She recovered and was taken back to the operating room during that same admission without incident. The patient has since been treated with systemic daptomycin and a tobramycin cement spacer without further incident.

Use of a Cholestyramine Washout in a Patient With Septic Shock on Leflunomide Therapy: A Case Report and Review of the Literature

Patients presenting with infections while receiving disease-modifying antirheumatic agents (DMARD) may be predisposed to a higher degree illness due to immunosuppression. This can be particularly problematic in patients who are receiving DMARDs with prolonged pharmacokinetic profiles. Leflunomide is a DMARD that has a prolonged half-life due to enterohepatic recirculation. We report a case of a patient with severe septic shock secondary to a prosthetic joint infection in which therapeutic levels of leflunomide were discovered, despite the patient ceasing therapy several weeks prior to admission. An orogastric cholestyramine washout was given to the patient to expedite the removal of the drug. Serum levels rapidly declined over the next several days, corresponding with resolution of her sepsis. A review of the literature relevant to the incidence of DMARD-related infections was conducted as well as discussion regarding the role of leflunomide drug monitoring and cholestyramine-facilitated removal of the drug in episodes of acute infectious syndromes.

Riedel's lobe of the liver: a case report

Riedel lobe of the liver is a simple anatomical variation, a downward tongue-like projection of the anterior edge of the right lobe of the liver to the right of the gallbladder with its typical case to be rare.We report the case of a 71-year-old woman with typical feature of a nonpalpable Riedel's lobe of the liver, as an incidental finding who was referred for reported hypergammaglobulinemia (22.7% [9%-19%]). Both features were attributed to a chronic inflammation because of an abscess in the right iliopsoas caused by infection due to bilateral hip replacement which underwent revision surgery. This was confirmed by her medical history, the imaging findings combined with elevated C-reactive protein, and by cross-reaction weak positive autoantibodies.Generally, knowledge or suspicion of Riedel's lobe of the liver is important, as it does not always remain clinically latent, as in our case, and it can be complicated by its torsion or hepatic tumors.

Histoplasma capsulatum endocarditis: multicenter case series with review of current diagnostic techniques and treatment

Infective endocarditis is an uncommon manifestation of infection with Histoplasma capsulatum. The diagnosis is frequently missed, and outcomes historically have been poor. We present 14 cases of Histoplasma endocarditis seen in the last decade at medical centers throughout the United States. All patients were men, and 10 of the 14 had an infected prosthetic aortic valve. One patient had an infected left atrial myxoma. Symptoms were present a median of 7 weeks before the diagnosis was established. Blood cultures yielded H. capsulatum in only 6 (43%) patients. Histoplasma antigen was present in urine and/or serum in all but 3 of the patients and provided the first clue to the diagnosis of histoplasmosis for several patients. Antibody testing was positive for H. capsulatum in 6 of 8 patients in whom the test was performed. Eleven patients underwent surgery for valve replacement or myxoma removal. Large, friable vegetations were noted at surgery in most patients, confirming the preoperative transesophageal echocardiography findings. Histopathologic examination of valve tissue and the myxoma revealed granulomatous inflammation and large numbers of organisms in most specimens. Four of the excised valves and the atrial myxoma showed a mixture of both yeast and hyphal forms on histopathology. A lipid formulation of amphotericin B, administered for a median of 29 days, was the initial therapy in 11 of the 14 patients. This was followed by oral itraconazole therapy, in all but 2 patients. The length of itraconazole suppressive therapy ranged from 11 months to lifelong administration. Three patients (21%) died within 3 months of the date of diagnosis. All 3 deaths were in patients who had received either no or minimal (1 day and 1 week) amphotericin B.

Intraspinal canal rod migration causing late-onset paraparesis 8 years after scoliosis surgery

INTRODUCTION

Complete intraspinal canal rod migration with posterior bone reconstitution has never been described in the adolescent idiopathic scoliosis (AIS) population. We present an unusual but significant delayed neurological complication after spinal instrumentation surgery.

CASE REPORT

A 24-year-old woman presented with lower limb weakness (ASIA D) 8 years after posterior instrumentation from T2 to L4 for AIS. CT scan and MRI demonstrated intra-canal rod migration with complete laminar reconstitution. The C-reactive protein was slightly elevated (fluctuated between 10 and 20 mg/l). Radiographs showed the convex rod had entered the spinal canal. The patient was taken into the operating room for thoracic spinal decompression and removal of the convex rod. This Cotrel-Dubousset rod, which had been placed on the convexity of the thoracic curve had completely entered the canal from T5 to T10 and was totally covered by bone with the eroded laminae entirely healed and closed. There was no pseudarthrosis. Intra-operatively, the fusion mass was opened along the whole length of this rod and the rod carefully removed and the spinal cord decompressed. The bacteriological cultures returned positive for Propionibacterium acnes. The patient recovered fully within 2 months post-operatively.

CONCLUSION

We opine that the progressive laminar erosion with intra-canal rod migration resulted from mechanical and infectious-related factors. The very low virulence of the strain of Propionibacterium acnes is probably involved in this particular presentation where the rod was trapped in the canal, owing to the quite extensive laminar reconstitution.

Early infection of hip joint prosthesis by Clostridium difficile in an HIV-1 infected patient

Anaerobes are less frequently described as causative pathogen of prosthetic joint infection (PJI). We report the first case of early PJI after hip arthroplasty due to Clostridium difficile in a diabetic and HIV-1 infected patient with bacteremia. Our patient was successfully treated through surgical debridement and prosthesis retention combined with targeted antibiotic therapy.

Pulmonary homograft endocarditis and aortic autograft failure after Ross procedure: a double stentless bioprosthesis approach

The case is reported of a 38-year-old male patient with pulmonary homograft acute infective endocarditis and aortic root dilation that occurred 13 years after a Ross procedure for bicuspid aortic valve regurgitation. Aortic and pulmonary root replacements were performed, using a Freestyle stentless aortic root bioprosthesis in both cases, with excellent hemodynamics on postoperative echocardiography. In addition, preoperative systemic septic embolization had occurred despite an absence of left-sided endocarditis, presumably due to an intrapulmonary shunt. This case report demonstrates the feasibility of a double stentless bioprosthesis approach, and stresses the need to remain vigilant for septic embolization even in isolated right-sided endocarditis.

[Morbimortality of infective endocarditis associated with permanent cardiovascular implantable electronic devices]

Infective endocarditis (IE) associated with permanent cardiovascular implantable electronic devices (CIEDs) is a complication of low frequency, but high mortality without adequate treatment. Progress on the knowledge of this disease and the development of therapeutic strategies such as early diagnosis, antibiotic management and better extraction techniques, among others, have improved the prognosis of these patients. The objectives of this study were to evaluate the in-hospital and out-of-hospital morbidity, and analyze some factors that explain the differences among the published mortality data. Patients diagnosed with IE associated with CIEDs were studied, retrospectively, between March/2002 and March/2011. We analyzed baseline, diagnostic and therapeutic characteristics, and in-hospital and out-of-hospital courses of the disease. We included 26 cases treated in our hospital, 23 of whom were referred from other centers for diagnosis and treatment. The average age of the patients was 67.5 years. All patients received antibiotics for six weeks and underwent complete removal of the device system, in 95% of patients by percutaneous extraction and 2 patients required a median sternotomy, atriotomy and epicardial pacemaker placement. Mortality was 4% and the follow up mortality was zero. The in-hospital morbidity was 31%. In the follow-ups there were no reinfections or other complications. In conclusion, IE is a serious condition that has a high morbidity with prolonged hospital stays, but with a low mortality. The explanation may lie in the use percutaneous extraction techniques, experience, complete extraction of the device system, the time of reimplantation of the new device and early treatment, among other factors.