Risk factors for surgical site infection in kidney transplant recipients

Surgical site infections after kidney transplantation are independently associated with graft loss

Surgical site infections (SSIs) are common health care-associated infections. SSIs after kidney transplantation (K-Tx) can endanger patient and allograft survival. Multicenter studies on this early posttransplant complication are scarce. We analyzed consecutive adult K-Tx recipients enrolled in the Swiss Transplant Cohort Study who received a K-Tx between May 2008 and September 2020. All data were prospectively collected with the exception of the categorization of SSI which was performed retrospectively according to the Centers for Disease Control and Prevention criteria. A total of 58 out of 3059 (1.9%) K-Tx recipients were affected by SSIs. Deep incisional (15, 25.9%) and organ/space infections (34, 58.6%) predominated. In the majority of SSIs (52, 89.6%), bacteria were detected, most frequently Escherichia coli (15, 28.9%), Enterococcus spp. (14, 26.9%), and coagulase-negative staphylococci (13, 25.0%). A BMI ≥25 kg/m2 (multivariable OR 2.16, 95% CI 1.07-4.34, P = .023) and delayed graft function (multivariable OR 2.88, 95% CI 1.56-5.34, P = .001) were independent risk factors for SSI. In Cox proportional hazard models, SSI was independently associated with graft loss (multivariable HR 3.75, 95% CI 1.35-10.38, P = .011). In conclusion, SSI was a rare complication after K-Tx. BMI ≥25 kg/m2 and delayed graft function were independent risk factors. SSIs were independently associated with graft loss.

Prospective evaluation of a closed-incision negative pressure wound therapy system in kidney transplantation and its association with wound complications

Introduction

Wound complications can cause considerable morbidity in kidney transplantation. Closed-incision negative pressure wound therapy (ciNPWT) systems have been efficacious in reducing wound complications across surgical specialties. The aims of this study were to evaluate the use of ciNPWT, Prevena™, in kidney transplant recipients and to determine any association with wound complications.

Material and methods

A single-center, prospective observational cohort study was performed in 2018. A total of 30 consecutive kidney transplant recipients deemed at high risk for wound complications received ciNPWT, and the results were compared to those of a historical cohort of subjects who received conventional dressings. Analysis for recipients with obesity and propensity score matching were performed.

Results

In total, 127 subjects were included in the analysis. Of these, 30 received a ciNPWT dressing and were compared with 97 subjects from a non-study historical control group who had conventional dressing. The overall wound complication rate was 21.3% (27/127). There was no reduction in the rate of wound complications with ciNPWT when compared with conventional dressing [23.3% (7/30) and 20.6% (20/97), respectively, p = 0.75]. In the obese subset (BMI ≥30 kg/m2), there was no significant reduction in wound complications [31.1% (5/16) and 36.8% (7/19), respectively, p = 0.73]. Propensity score matching yielded 26 matched pairs with equivalent rates of wound complications (23.1%, 6/26).

Conclusion

This is the first reported cohort study evaluating the use of ciNPWT in kidney transplantation. While ciNPWT is safe and well tolerated, it is not associated with a statistically significant reduction in wound complications when compared to conventional dressing. The findings from this study will be used to inform future studies associated with ciNPWT in kidney transplantation.

Single-center experience with perioperative antibiotic prophylaxis and surgical site infections in kidney transplant recipients

BACKGROUND

Infections in kidney transplant recipients are particularly challenging owing to the immunosuppressive treatment, usually long history of chronic illness, comorbidities and prior exposures to antibiotics. Among the most common complications early after surgery are surgical site infections. The aim of this study was to identify risk factors and evaluate epidemiological data regarding surgical site infections. Moreover, we were able to compare the current results with historical data from our institution when different perioperative antibiotic prophylaxis was practiced.

METHODS

We conducted a retrospective case-control study in a group of 254 deceased donor renal graft recipients transplanted in a single Central European institution. We evaluated epidemiological findings and resistance patterns of pathogens causing surgical site infections. We used multivariable logistic regression to determine risk factors for surgical site infections.

RESULTS

We revealed no differences in baseline characteristics between patients with and without surgical site infections. Ten surgical site infections (3.9%) were diagnosed (six superficial incisional, two deep incisional, and two organ/space). Eight species (19 strains) were identified, most of which were multi-drug resistant (63%). The most common was extended-spectrum β-lactamase producing Klebsiella pneumoniae (26%). We showed that statistically significant differences were present between reoperated and non-reoperated patients (adjusted odds ratio: 6.963, 95% confidence interval 1.523-31.842, P = .012).

CONCLUSIONS

Reoperation is an individual risk factor for surgical site infection after kidney transplantation. According to our experience, cefazolin-based prophylaxis can be safe and is associated with relatively low prevalence of surgical site infections.

Surgical site infection prevention and management in immunocompromised patients: a systematic review of the literature

BACKGROUND

Immunocompromised patients are at higher risk of surgical site infection and wound complications. However, optimal management in the perioperative period is not well established. Present systematic review aims to analyse existing strategies and interventions to prevent and manage surgical site infections and other wound complications in immunocompromised patients.

METHODS

A systematic review of the literature was conducted.

RESULTS

Literature review shows that partial skin closure is effective to reduce SSI in this population. There is not sufficient evidence to definitively suggest in favour of prophylactic negative pressure wound therapy. The use of mammalian target of rapamycin (mTOR) and calcineurin inhibitors (CNI) in transplanted patient needing ad emergent or undeferrable abdominal surgical procedure must be carefully and multidisciplinary evaluated. The role of antibiotic prophylaxis in transplanted patients needs to be assessed.

CONCLUSION

Strict adherence to SSI infection preventing bundles must be implemented worldwide especially in immunocompromised patients. Lastly, it is necessary to elaborate a more widely approved definition of immunocompromised state. Without such shared definition, it will be hard to elaborate the needed methodologically correct studies for this fragile population.

Surgical Site Infections in Liver Transplant Patients: A Single-Center Experience

AIM

The aim of the study was a single-center assessment of occurrence of surgical site infections (SSI) in patients after liver transplantation and an attempt to determine factors that may contribute to this complication.

PATIENTS AND METHODS

Analysis of medical records of 60 adult patients, who underwent first transplantation in 2016 and 2017 was conducted. Selected pre-, intra-, and postoperative factors were assessed. Statistical analysis was performed with StatSoft Statistica 13.1 PL package.

RESULTS

SSI occurred in 25% of liver recipients, with average timing of diagnosis on the 14th day after surgery. Mean duration of hospitalization was significantly longer in patients who experienced SSI than in patients without this complication (35.8 ± 8.9 days vs 25.2 ± 6 days, P < .0001). SSI occurred a little more frequently in men and older recipients, as well as in overweight and underweight patients (not significant). An indication for transplantation did not have an impact on SSI occurrence. The complication was more likely in patients with diabetes and renal failure prior to transplantation (P > .05). Duration of the procedure, blood loss and prolonged drainage did not have any impact on SSIs. SSI was significantly more common in recipients with lower total protein value (P < .0002) and anemia (P < .0002) in early postoperative period.

CONCLUSION

Among the studied population, a high incidence of SSI was noted, and that some of the identified risk factors differ from those described in the literature.

Machine learning for the prediction of severe pneumonia during posttransplant hospitalization in recipients of a deceased-donor kidney transplant

Background

Pneumonia accounts for the majority of infection-related deaths after kidney transplantation. We aimed to build a predictive model based on machine learning for severe pneumonia in recipients of deceased-donor transplants within the perioperative period after surgery.

Methods

We collected the features of kidney transplant recipients and used a tree-based ensemble classification algorithm (Random Forest or AdaBoost) and a nonensemble classifier (support vector machine, Naïve Bayes, or logistic regression) to build the predictive models. We used the area under the precision-recall curve (AUPRC) and the area under the receiver operating characteristic curve (AUROC) to evaluate the predictive performance via ten-fold cross validation.

Results

Five hundred nineteen patients who underwent transplantation from January 2015 to December 2018 were included. Forty-three severe pneumonia episodes (8.3%) occurred during hospitalization after surgery. Significant differences in the recipients' age, diabetes status, HBsAg level, operation time, reoperation, usage of anti-fungal drugs, preoperative albumin and immunoglobulin levels, preoperative pulmonary lesions, and delayed graft function, as well as donor age, were observed between patients with and without severe pneumonia (P<0.05). We screened eight important features correlated with severe pneumonia using the recursive feature elimination method and then constructed a predictive model based on these features. The top three features were preoperative pulmonary lesions, reoperation and recipient age (with importance scores of 0.194, 0.124 and 0.078, respectively). Among the machine learning algorithms described above, the Random Forest algorithm displayed better predictive performance, with a sensitivity of 0.67, specificity of 0.97, positive likelihood ratio of 22.33, negative likelihood ratio of 0.34, AUROC of 0.91, and AUPRC of 0.72.

Conclusions

The Random Forest model is potentially useful for predicting severe pneumonia in kidney transplant recipients. Recipients with a potential preoperative potential pulmonary infection, who are of older age and who require reoperation should be monitored carefully to prevent the occurrence of severe pneumonia.

Evaluation of the Renal Transplant Recipient in the Emergency Department

Renal transplants are becoming more and more frequent in the United States and worldwide. Studies demonstrate that these patients inevitably end up visiting an emergency department. In addition to typical medical and surgical problems encountered in the general population, this group of patients has unique problems arising from their immunocompromised state and also due to side effects of the medications required. This article discusses these risks and management decisions that the emergency department physician should be aware of in order to prevent adverse outcomes for the patient and transplanted kidney.

Reoperation in Early Kidney Post-transplant Period as a Strong Risk Factor of Surgical Site Infection Occurrence

BACKGROUND

One of the most common infective complications after kidney transplant (KTx) is surgical site infection (SSI). Providing indications of improvement of perioperative antibiotic prophylaxis (PAP) and allowing the characterization of risk factors are critical to reduce SSI. The purpose of this study was to evaluate the SSI risk factors and impact of reoperation in the early post-transplant period on SSI occurrence and assess if standard PAP in those cases is a best consideration.

METHODS

Between April 2014 and October 2015, a total of 236 KTxs were performed in our center. Deceased donor data, recipient data, and data related to surgical procedures were collected.

RESULTS

Surgical site infections were reported in 5.6% (12/214) of patients. Seven patients were diagnosed as having superficial SSI (7/12; 58.3%), 2 with deep SSI (2/12; 16.6%), and 4 with organ-specific SSI (4/12; 33.3%). Extended criteria donor-related transplant, cold ischemia time > 22 hours, dialysis period > 30 months, recipient age older than 45 years, recipient body mass index > 27, induction therapy prior to transplant, diabetes prior to transplant, and ≥ 1 reoperation during 30 days of observation were independent risk factors of SSI occurrence. A total of 19 reoperations were performed in 17 patients. In 8 of all 12 patients with SSI diagnosis, the reoperation was performed (66.7%). In 202 patients of non-SSI patients, only 9 reoperations were performed (4.5%).

CONCLUSIONS

Early reoperation after Ktx is a strong risk factor of SSI occurrence. There is a probability that > 4 SSI risk factors and reoperation in the early post-transplant period could require different and more aggressive proceeding, as standard PAP in those cases is insufficient.

Surgical site infections: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of post-operative surgical site infections (SSIs) in solid organ transplantation. SSIs are a significant cause of morbidity and mortality in SOT recipients. Depending on the organ transplanted, SSIs occur in 3%-53% of patients, with the highest rates observed in small bowel/multivisceral, liver, and pancreas transplant recipients. These infections are classified by increasing invasiveness as superficial incisional, deep incisional, or organ/space SSIs. The spectrum of organisms implicated in SSIs in SOT recipients is more diverse than the general population due to other important factors such as the underlying end-stage organ failure, immunosuppression, prolonged hospitalizations, organ transportation/preservation, and previous exposures to antibiotics in donors and recipients that could predispose to infections with multidrug-resistant organisms. In this guideline, we describe the epidemiology, clinical presentation, differential diagnosis, potential pathogens, and management. We also provide recommendations for the selection, dosing, and duration of peri-operative antibiotic prophylaxis to minimize post-operative SSIs.

Minimally Invasive, Laparoscopic, and Robotic-assisted Techniques Versus Open Techniques for Kidney Transplant Recipients: A Systematic Review

CONTEXT

Literature on conventional and minimally invasive operative techniques has not been systematically reviewed for kidney transplant recipients.

OBJECTIVE

To systematically evaluate, summarize, and review evidence supporting operating technique and postoperative outcome for kidney transplant recipients.

EVIDENCE ACQUISITION

A systematic review was conducted in PubMed-Medline, Embase, and Cochrane Library between 1966 up to September 1, 2016, according to Preferred Reporting Items for Systematic Review and Meta-analysis guidelines. Articles were included and scored by two independent reviewers using Group Reading Assessment and Diagnostic Evaluation (GRADE), Newcastle-Ottawa Quality Assessment Scale (NOS), and Oxford guidelines for level of evidence. Main outcomes were graft survival, surgical site infection, incisional hernia, and cosmetic result. In total, 18 out of 1954 identified publications were included in this analysis.

EVIDENCE SYNTHESIS

Included reports described conventional open, minimally invasive open, laparoscopic, and robotic-assisted techniques. General level of evidence of included studies was low (GRADE: 1-3; NOS: 0-4; and Oxford level of evidence: 4-2). No differences in graft or patient survival were found. For open techniques, Gibson incision showed better results than the hockey-stick incision for incisional hernia (4% vs 16%), abdominal wall relaxation (8% vs 24%), and cosmesis. Minimally invasive operative recipient techniques showed lowest surgical site infection (range 0-8%) and incisional hernia rates (range 0-6%) with improved cosmetic result and postoperative recovery. Disadvantages included prolonged cold ischemia time, warm ischemia time, and total operation time.

CONCLUSIONS

Although the level of evidence was generally low, minimally invasive techniques showed promising results with regard to complications and recovery, and could be considered for use. For open surgery, the smallest possible Gibson incision appeared to yield favorable results.

PATIENT SUMMARY

In this paper, the available evidence for minimally invasive operation techniques for kidney transplantation was reviewed. The quality of the reviewed research was generally low but suggested possible advantages for minimally invasive, laparoscopic, and robot-assisted techniques.

Improving Risk Adjustment Above Current Centers for Disease Control and Prevention Methodology Using Electronically Available Comorbid Conditions

OBJECTIVE To identify comorbid conditions associated with surgical site infection (SSI) among patients undergoing renal transplantation and improve existing risk adjustment methodology used by the Centers for Disease Control and Prevention National Healthcare Safety Network (NHSN). PATIENTS Patients (≥18 years) who underwent renal transplantation at University of Maryland Medical Center January 1, 2010-December 31, 2011. METHODS Trained infection preventionists reviewed medical records to identify surgical site infections that developed within 30 days after transplantation, using NHSN criteria. Patient demographic characteristics and risk factors for surgical site infections were identified through a central data repository. International Statistical Classification of Disease, Ninth Revision, Clinical Modification codes were used to analyze individual component comorbid conditions and calculate the Charlson and Elixhauser comorbidity indices. These indices were compared with the current NHSN risk adjustment methodology. RESULTS A total of 441 patients were included in the final cohort. In bivariate analysis, the Charlson components of cerebrovascular disease, peripheral vascular disease, and rheumatologic disorders and Elixhauser components of obesity, rheumatoid arthritis, and weight loss were significantly associated with the outcome. A model utilizing the variables from the NHSN methodology had a c-statistic of 0.56 (95% CI, 0.48-0.63), whereas a model that also included comorbidities from the Charlson and Elixhauser indices had a c-statistic of 0.65 (95% CI, 0.58-0.73). The model with all 3 risk adjustment scores performed best and was statistically different from the NHSN model alone, demonstrated by improvement in the c statistic (0.65 vs 0.56). CONCLUSION Risk adjustment models should incorporate electronically available comorbid conditions. Infect Control Hosp Epidemiol 2016;1-6.

Surgical site infection after renal transplantation

OBJECTIVE

To identify factors associated with the development of surgical site infection (SSI) among adult patients undergoing renal transplantation

DESIGN

A retrospective cohort study.

SETTING

An urban tertiary care center in Baltimore, Maryland, with a well-established renal transplantation program that performs ~200-250 renal transplant procedures annually.

RESULTS

At total of 441 adult patients underwent renal transplantation between January 1, 2010, and December 31, 2011. Of these 441 patients, 66 (15%) developed an SSI; of these 66, 31 (47%) were superficial incisional infections and 35 (53%) were deep-incisional or organ-space infections. The average body mass index (BMI) among this patient cohort was 29.7; 84 (42%) were obese (BMI >30). Patients who developed an SSI had a greater mean BMI (31.7 vs 29.4; P=.004) and were more likely to have a history of peripheral vascular disease, rheumatologic disease, and narcotic abuse. History of cerebral vascular disease was protective. Multivariate analysis showed BMI (odds ratio [OR] 1.06; 95% confidence interval [CI], 1.02-1.11) and past history of narcotic use/abuse (OR, 4.86; 95% CI, 1.24-19.12) to be significantly associated with development of SSI after controlling for National Healthcare Surveillance Network (NHSN) score and presence of cerebrovascular, peripheral vascular, and rheumatologic disease.

CONCLUSIONS

We identified higher BMI as a risk factor for the development of SSI following renal transplantation. Notably, neither aggregate comorbidity scores nor NHSN risk index were associated with SSI in this population. Additional risk adjustment measures and research in this area are needed to compare SSIs across transplant centers.

Wound morbidity after kidney transplant

CONTEXT

Wound morbidity is an important surgical complication after kidney transplant.

OBJECTIVE

To assess risk factors for postoperative wound complications and the impact of such complications on outcomes of kidney transplant.

DESIGN AND PATIENTS

Retrospectively, 108 consecutive kidney transplant patients between January 2010 and December 2010 were included in the analysis. Wound morbidity was defined as a surgical site infection or symptomatic lymphocele requiring intervention. Patient, donor, and surgical characteristics were reviewed.

RESULTS

Eight lymphoceles and 5 surgical site infections occurred in 12 patients. Risk factors for wound complications were recipient's age (P<.01), body mass index (P=.01), urinary tract infection (P=.01), and prolonged postoperative wound drainage (P=.047). Wound morbidity did not increase the incidence of delayed graft function, acute rejection, graft failure, or mortality. Obesity, recipient's age, urinary tract infection, and prolonged wound drainage are risk factors for wound-related complications. Graft and patient survival rates are comparable between patients with and without wound-related complications.

Surgical site and early urinary tract infections in 1000 kidney transplants with antimicrobial perioperative prophylaxis

Surgical site infections (SSIs) and early urinary tract infections (UTIs) are well recognized postoperative kidney transplant complications. These complications seldom lead to graft loss, although they may result in significant morbidity with prolonged hospitalization. Thus, perioperative antibiotic prophylaxis (PAP) has traditionally been used in this setting. Between April 1988 and December 2012, we identified 1000 kidney transplant recipients (33 from living donors) who underwent prophylaxis with ceftriaxone before the surgical procedure. A retrospective analysis was conducted to evaluate both the incidence rate and outcome of SSIs and UTIs. Recipients who developed SSIs were also assessed to identify risk factors and potential correlations with different immunosuppressive regimens. A total of 20 SSIs (2%) and 93 UTIs (9.3%) were observed. The most significant risk factor for SSIs was urine leak (15.38%; odds ratio [OR], 12.3; P < .0001) followed by sirolimus-based maintenance immunosuppression therapy (5%; OR, 2.97; P = .04) and induction therapy with either antithymocyte globulin or basiliximab (3.18%; OR, 3.45; P = .01). Sex was identified as the only risk factor for UTI (female vs male, 17.1% vs 4.6%; P < .0001). We believe universal ceftriaxone-based prophylaxis is useful for preventing SSIs and UTIs, considering its effectiveness and safety profile.

Amikacin prophylaxis and risk factors for surgical site infection after kidney transplantation

BACKGROUND

Antibiotic prophylaxis plays a major role in preventing surgical site infections (SSIs). This study aimed to evaluate antibiotic prophylaxis in kidney transplantation and identify risk factors for SSIs.

METHODS

We evaluated all kidney transplantation recipients from January 2009 and December 2012. We excluded patients who died within the first 72 hr after transplantation, were undergoing simultaneous transplantation of another organ, or were below 12 years of age. The main outcome measure was SSI during the first 60 days after transplantation.

RESULTS

A total of 819 kidney transplants recipients were evaluated, 65% of whom received a deceased-donor kidney. The antibiotics used as prophylaxis included cephalosporin, in 576 (70%) cases, and amikacin, in 233 (28%). We identified SSIs in 106 cases (13%), the causative agent being identified in 72 (68%). Among the isolated bacteria, infections caused by extended-spectrum β-lactamase-producing Enterobacteriaceae predominated. Multivariate analysis revealed that the risk factors for post-kidney transplantation SSIs were deceased donor, thin ureters at kidney transplantation, antithymocyte globulin induction therapy, blood transfusion at the transplantation procedure, high body mass index, and diabetes mellitus. The only factor associated with a reduction in the incidence of SSIs was amikacin use as antibiotic prophylaxis. Factors associated with reduced graft survival were: intraoperative blood transfusions, reoperation, human leukocyte antigen mismatch, use of nonstandard immunosuppression therapy, deceased donor, post-kidney transplantation SSIs, and delayed graft function.

CONCLUSION

Amikacin prophylaxis is a useful strategy for preventing SSIs.

Nosocomial infections within the first month of solid organ transplantation

Infections remain a common complication of solid organ transplantation. Early postoperative infections remain a significant cause of morbidity and mortality in solid organ transplant (SOT) recipients. Although significant effort has been made to understand the epidemiology and risk factors for early nosocomial infections in other surgical populations, data in SOT recipients are limited. A literature review was performed to summarize the current understanding of pneumonia, urinary tract infection, surgical-site infection, bloodstream infection, and Clostridium difficult colitis, occurring within the first 30 days after transplantation.

Surgical site infections after kidney transplantation--where do we stand now?

BACKGROUND

Kidney transplantation (KTx) is a widely accepted method of renal function replacement therapy. Surgical site infections (SSIs), along with urinary tract infections, are among the most common infective complications after KTx. The purpose of this study was to assess the incidence of SSI in patients after KTx, identify risk factors for SSI, and classify patients in which standard antibiotic prophylaxis could be avoided.

METHODS

Between January 2010 and December 2011, 262 KTxs were performed in our center. Deceased donors', recipients' data, and data related to surgical procedures were collected. SSIs were diagnosed in accordance with the guidelines published by the U.S. Centers for Disease Control and Prevention.

RESULTS

SSIs were diagnosed in 7.25% (19/262) of patients. Of nineteen SSI patients, two (10.5%) were diagnosed with organ-specific SSIs, which eventually led to graft loss; six (31.5%) developed deep incisional SSIs; and eleven (58%) developed superficial incisional SSIs. Through analysis of this extensive data set, we determined the following risk factors for the development of SSI: kidney from extended criteria donors, a cold ischemia time of more than 30 hr, time of surgical procedure longer than 200 min, confirmed diabetes in the recipients, a recipient body mass index higher than 27 kg/m, and occurrence of delayed graft function.

CONCLUSIONS

It may be possible to reduce standard antibiotic prophylaxis to a single dose in patients without known risk factors for SSI. Any opportunity to reduce antibiotic use is crucial in preventing the development of multi-drug-resistant pathogens.