Outcome, Incidence, and Timing of Infectious Complications in Small Bowel and Multivisceral Organ Transplantation Patients

Multidrug-resistant Klebsiella Pneumoniae Infection Led to Resection of the Graft in a Small Bowel Transplant Recipient: A Case Report and Review of the Literature

BACKGROUND

Infection due to multidrug-resistant Klebsiella pneumoniae is a common cause of graft resection after small bowel transplantation. We report a failed case in which the intestinal graft was resected 18 days after the operation due to postoperative infection with multidrug-resistant K pneumoniae and a literature review of other common causes of small bowel transplantation failure have been reported.

METHODS

A female, 29 years of age, underwent partial living small bowel transplantation for short bowel syndrome. After the operation, the patient was infected with multidrug-resistant K pneumoniae, even though various anti-infective regimens were employed. It further developed into sepsis and disseminated into intravascular coagulation, leading to exfoliation and necrosis of the intestinal mucosa. Finally, the intestinal graft had to be resected to save the patient's life.

RESULTS

Multidrug-resistant K pneumoniae infection often affects the biological function of intestinal grafts and can even lead to necrosis. Other common causes of failure, including postoperative infection, rejection, post-transplantation lymphoproliferative disorder, graft-vs-host disease, surgical complications, and other related diseases, were also discussed throughout the literature review.

CONCLUSIONS

Pathogenesis due to diverse and interrelated factors makes the survival of intestinal allografts a great challenge. Therefore, only by fully understanding and mastering the common causes of surgical failure can the success rate of small bowel transplantation be effectively improved.

Pediatric intestinal transplantation

Advancements in donor management, organ preservation and operative techniques, as well as immunosuppressive therapies, have provided children with intestinal failure and its complications a chance not only for enteral autonomy but also long-term survival through intestinal transplantation (ITx). First described in the 1960's, experience has grown in managing these complex patients both pre- and post-transplant. The goals of this review are to provide a brief history of intestinal transplantation and intestinal rehabilitation in pediatric patients, followed by focused discussions of the indications for ITx, induction and maintenance immunosuppression therapies, common post-operative complications, and outcomes/quality of life post-transplant.

Donor-derived vancomycin-resistant enterococci transmission and bloodstream infection after intestinal transplantation

BACKGROUND

Transplant recipients are at high risk for infections. However, donor-recipient transmission of multidrug-resistant organisms (MDROs) remains mostly unaddressed in the protocols of pre-transplant infection and colonization screening. Vancomycin-resistant enterococci (VRE) are MDROs that colonize the gastrointestinal tract and are associated with a significant burden of disease. Besides the high mortality of invasive VRE infections, chronic colonization leads to costly isolation measures in the hospital setting. Whereas most post-transplantation VRE infections are endogenous and thus preceded by colonization of the recipient, conclusive evidence of VRE transmission via allograft in the context of intestinal transplantation is lacking.

CASE PRESENTATION

We describe a donor-derived VRE infection after intestinal transplantation including small bowel and right hemicolon. The recipient, a 54-year old male with history of mesenteric ischemia and small bowel perforation due to generalized atherosclerosis and chronic stenosis of the celiac trunk and the superior mesenteric artery, developed an intra-abdominal infection and bloodstream infection after transplantation. VRE isolates recovered from the patient as well as from the allograft prior to transplantation were analyzed via whole genome sequencing. Isolates showed to be genetically identical, thus confirming the transmission from donor to recipient.

CONCLUSIONS

This case underlines the relevance of donor-recipient VRE transmission and invasive infection in the context of intestinal transplantation, highlighting the need for preoperative MDRO screening that facilitates the prompt and effective treatment of possible infections as well as the timely establishment of contact precautions to prevent further spread.

Perioperative antibiotics for preventing post-surgical site infections in solid organ transplant recipients

BACKGROUND

Solid organ transplant recipients are at high risk for infections due to the complexity of surgical procedures combined with the impact of immunosuppression. No consensus exists on the role of antibiotics for surgical site infections in solid organ transplant recipients.

OBJECTIVES

To assess the benefits and harms of prophylactic antimicrobial agents for preventing surgical site infections in solid organ transplant recipients.

SEARCH METHODS

The Cochrane Kidney and Transplant Register of Studies was searched up to 21 April 2020 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov.

SELECTION CRITERIA

All randomised controlled trials (RCTs) and quasi-RCTs in any language assessing prophylactic antibiotics in preventing surgical site infections in solid organ transplant recipients at any time point after transplantation.

DATA COLLECTION AND ANALYSIS

Two authors independently determined study eligibility, assessed quality, and extracted data. Primary outcomes were surgical site infections and antimicrobial resistance. Other outcomes included urinary tract infections, pneumonias and septicaemia, death (any cause), graft loss, graft rejection, graft function, adverse reactions to antimicrobial agents, and outcomes identified by the Standardised Outcomes of Nephrology Group (SONG), specifically graft health, cardiovascular disease, cancer and life participation. Summary effect estimates were obtained using a random-effects model and results were expressed as risk ratios (RR) and 95% confidence intervals (CI). The quality of the evidence was assessed using the risk of bias and the GRADE approach.

MAIN RESULTS

We identified eight eligible studies (718 randomised participants). Overall, five studies (248 randomised participants) compared antibiotics versus no antibiotics, and three studies (470 randomised participants) compared extended duration versus short duration antibiotics. Risk of bias was assessed as high for performance bias (eight studies), detection bias (eight studies) and attrition bias (two studies). It is uncertain whether antibiotics reduce the incidence of surgical site infections as the certainty of the evidence has been assessed as very low (RR 0.42, 95% CI 0.21 to 0.85; 5 studies, 226 participants; I² = 25%). The certainty of the evidence was very low for all other reported outcomes (death, graft loss, and other infections). It is uncertain whether extended duration antibiotics reduces the incidence of surgical site infections in either solid organ transplant recipients (RR 1.19, 95% CI 0.58 to 2.48; 2 studies, 302 participants; I² = 0%) or kidney-only transplant recipients (RR 0.50, 95% CI 0.05 to 5.48; 1 study, 205 participants) as the certainty of the evidence has been assessed as very low. The certainty of the evidence was very low for all other reported outcomes (death, graft loss, and other infections). None of the eight included studies evaluated antimicrobial agent adverse reactions, graft health, cardiovascular disease, cancer, life participation, biochemical and haematological parameters, intervention cost, hospitalisation length, or overall hospitalisation costs.

AUTHORS' CONCLUSIONS

Due to methodological limitations, risk of bias and significant heterogeneity, the current evidence for the use of prophylactic perioperative antibiotics in transplantation is of very low quality. Further high quality, adequately powered RCTs would help better inform clinical practice.

Clostridium difficile infection mimics intestinal acute cellular rejection in pediatric multivisceral transplant-A case series

Clostridium difficile infection (CDI) is the most common health care-associated infection in the United States. Thirty-nine percent of intestinal transplant recipients may develop CDI. Induction of rejection has been reported as a rare event. To our knowledge, this will be the second report of an association between CDI and rejection in the literature. We describe our experience with four pediatric MVT recipients, three of whom on treatment of their CDI alone had resolution of biopsy findings of intestinal ACR. Our patients were males aged 2-5 years old who had their first CDI post-MVT occurring from 2 months to 15 months post-transplant. All first episodes of CDI were treated with a 10-14 day course of metronidazole with one additionally receiving vancomycin. All four recipients had recurrent CDI, and two recipients had septic shock as a manifestation of their CDI. Three recipients had biopsies showing mild rejection during episodes of CDI, and treatment of the CDI resulted in resolution of biopsy findings of rejection. Our case series suggests CDI may mimic ACR on intestinal biopsy. Treatment of rejection during active CDI carries the risk of over-suppression and worsening of CDI. Our experience has taught us that surveillance endoscopy for rejection may be deceiving during an active CDI, and if mild acute rejection is noted during active CDI, treatment of rejection can be safely delayed and potentially avoided.

Intra-abdominal infections among adult intestinal and multivisceral transplant recipients in the 2-year post-operative period

BACKGROUND

Intestinal and multivisceral transplantations are treatment options for patients with intestinal failure. Transplantation is often complicated by abdominal and/or bloodstream infections in the post-operative period.

METHODS

A retrospective chart review of all adults who underwent intestinal or multivisceral transplantation at our institution from 2003 to 2015 was performed. Data were collected for 2 years post transplant.

RESULTS

A total of 106 intestinal or multivisceral transplants were performed in 103 patients. The median age at the time of transplant was 44 (IQR: 34-52) with 55% (n = 58) male and 45% (n = 48) female. There were 46 (43%) intra-abdominal infections post transplant among the 103 patients, and six transplant recipients (13%) developed concurrent bloodstream infections. The median time to first intra-abdominal infection was 23 days (IQR: 10-48). For those with organisms isolated in culture, forty-seven percent of the isolates were gram negative, 39% gram positive, 7% anaerobes, and 7% yeast. The most common isolates were enterococci at 28%, E. coli at 14%, and Klebsiella spp at 13%. Sixty-three percent of the enterococci were vancomycin-resistant enterococci (VRE), and 22% of the gram-negative isolates were extended spectrum beta-lactamases (ESBLs). Patients with intra-abdominal infections had longer hospital post-transplant length of stays at a median of 35 days (IQR: 25-48) vs 23 days (IQR: 17-33) for those without infections, P = .0012. There was no difference in all-cause mortality in patients with or without intra-abdominal infections, P = .654.

CONCLUSIONS

Intra-abdominal infections are common in intestinal or multivisceral transplant recipients, but despite this complication, we found no increased risk of mortality. These transplant recipients are also at risk for infection with drug-resistant organisms.

Candida infections in solid organ transplantation: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These updated guidelines from the American Society of Transplantation Infectious Diseases Community of Practice provide recommendations for the diagnosis and management of Candida infections in solid organ transplant recipients. Candida infections manifest primarily as candidemia and invasive candidiasis and cause considerable morbidity and mortality. Early diagnosis and initiation of treatment are necessary to reduce mortality. For both candidemia and invasive candidiasis, an echinocandin is recommended for initial therapy. However, early transition to oral therapy is encouraged when patients are stable and the organism is susceptible. Candida prophylaxis should be targeted for high-risk patients in liver, small bowel, and pancreas transplant recipients. Future research should address which patient groups may benefit most from preventative antifungal therapy strategies.

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.

Intestinal re-transplantation: indications, techniques and outcomes

PURPOSE OF REVIEW

The field of intestinal transplantation has shown significant growth and has become the gold standard therapy for patients that suffer from the complications of total parenteral nutrition due to irreversible intestinal failure. In the early years of intestinal transplant, retransplantation was associated with extremely high morbidity and mortality. The purpose of this review is to summarize recent encouraging reports, showing significant improvement in outcomes after intestinal retransplantation.

RECENT FINDINGS

Recent studies at large volume centers have reported significant progress in patient and graft survival after intestinal retransplantation. Recent literature described the most common indications for retransplantation, surgical techniques, timing of graft enterectomy, immunologic monitoring, and complications. Improvement in outcomes due to advances in immunosuppression management and the importance of liver-containing grafts are also described.

SUMMARY

Improving early to midterm patient and graft survival has made consideration for intestinal retransplantation even more necessary. Current clinical evidence supports the benefit of intestinal retransplantation in well selected recipients. Initial immunosuppression protocols, technical modifications, proper timing of enterectomy, and improved infectious disease monitoring have contributed to improved outcomes.

Pneumonia in solid organ transplantation: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These guidelines from the AST Infectious Diseases Community of Practice review the diagnosis and management of pneumonia in the post-transplant period. Clinical presentations and differential diagnosis for pneumonia in the solid organ transplant recipient are reviewed. A two-tier approach is proposed based on the net state of immunosuppression and the severity of presentation. With a lower risk of opportunistic, hospital-acquired, or exposure-specific pathogens and a non-severe presentation, empirical therapy may be initiated under close clinical observation. In all other patients, or those not responding to the initial therapy, a more aggressive diagnostic approach including sampling of tissue for microbiological and pathological testing is warranted. Given the broad range of potential pathogens, a microbiological diagnosis is often key for optimal care. Given the limited literature comparatively evaluating diagnostic approaches to pneumonia in the solid organ transplant recipient, much of the proposed diagnostic algorithm reflects clinical experience rather than evidence-based data. It should serve as a template which may be modified according to local needs. The same holds true for the suggested empiric therapies, which need to be adapted to the local resistance patterns. Further study is needed to comparatively evaluate diagnostic and empiric treatment strategies in SOT recipients.

Comparison in outcome with tailored antibiotic prophylaxis postoperatively in pediatric intestinal transplant population

BIs are ubiquitous among the pediatric intestinal transplant patient population. Personalizing postoperative prophylaxis antibiotic regimens may improve outcomes in this population. A retrospective analysis of all pediatric patients who underwent intestinal transplantation was evaluated to compare standardized and tailored regimens of antibiotics provided as prophylaxis postoperatively. Patients in the standard group have both shorter time to and higher rate of BIs, which was statistically significant (P < 0.001). Of the children who developed a BI, there was no statistical difference in average times to the development of a second BI (293 vs 119 days, P = 0.211). The tailored group had prolonged times until the development of a MDRO (52.6 vs 63.9 days, P = 0.677). Although not statistically significant, the tailored group had a propensity to present with gram-negative pathogens after transplant as compared to the standard regimen group, which presented with gram-positive pathogens (P = 0.103). Children with a history of an MDRO held a 7.3 (P < 0.01) times more likelihood of death within a year of transplant. A tailored prophylactic antibiotic regimen in the post-transplant period appears to prolong the time to the first BI. Although the data do not show differences in mortality, further study may prove the impact of a tailored antibiotic regimen on morbidity and mortality rates.

Cochlear Implantation in Organ Transplant Recipients

OBJECTIVE

Immunosuppressed individuals who have undergone organ transplants, especially children, pose particular challenges in terms of treatment. The aim of this study was to analyze the postoperative complication rate of organ transplant recipients who have also received a cochlear implant (CI).

STUDY DESIGN

Retrospective case series.

SETTING

Tertiary referral center.

INTERVENTION

The case series includes 13 kidney, liver, lung, and heart transplant patients. Age at treatment ranged from 2 to 71 years, with a total of 17 CIs.

MAIN OUTCOME MEASURES

Postoperative complications were classified into major and minor, early (within 3 mo postoperatively) and late (>3 mo postoperatively). The results were compared with those for 13 1:1 matched pairs obtained and from our database and a healthy patient collective from our department.

RESULTS

The global postoperative complication rate was 29.4%. The proportion of patients suffering major complications was 17.6%, with 17.6% having minor complications. Complications that occurred early accounted for 13.3%, and late for 26.7%. No adults, and 33.0% of children, showed any complications after cochlear implantation. The global complication rate (29.4%) was significantly increased compared with the matched pairs (0%, p = 0.013) and department data (13.8%, p = 0.006; Cramers v = 0.102).

CONCLUSION

This study demonstrates that organ transplant recipients, and especially children, are at increased risk of postoperative complications after cochlear implantation in comparison with healthy CI recipients.

Pediatric Intestinal Transplantation

Pediatric intestinal transplantation has moved from the theoretic to an actual therapy for children with irreversible intestinal failure who are suffering from complications of total parenteral nutrition. Owing to significant advancement in the management of intestinal failure and prevention of parenteral nutrition-related complications that have led to reduction in incidence of parenteral nutrition-associated liver disease and have improved intestinal adaptation, the indications for intestinal transplantation are evolving. Long-term outcomes have improved, but challenges in long-term graft function owing to chronic rejection and immunosuppressant-related complications remain the major opportunities for improvement.

Gut microbiota and its implications in small bowel transplantation

The gut microbiota is mainly composed of a diverse population of commensal bacterial species and plays a pivotal role in the maintenance of intestinal homeostasis, immune modulation and metabolism. The influence of the gut microbiota on solid organ transplantation has recently been recognized. In fact, several studies indicated that acute and chronic allograft rejection in small bowel transplantation (SBT) is closely associated with the alterations in microbial patterns in the gut. In this review, we focused on the recent findings regarding alterations in the microbiota following SBTand the potential roles of these alterations in the development of acute and chronic allograft rejection. We also reviewed important advances with respect to the interplays between the microbiota and host immune systems in SBT. Furthermore, we explored the potential of the gut microbiota as a microbial marker and/or therapeutic target for the predication and intervention of allograft rejection and chronic dysfunction. Given that current research on the gut microbiota has become increasingly sophisticated and comprehensive, large cohort studies employing metagenomic analysis and multivariate linkage should be designed for the characterization of host-microbe interaction and causality between microbiota alterations and clinical outcomes in SBT. The findings are expected to provide valuable insights into the role of gut microbiota in the development of allograft rejection and other transplant-related complications and introduce novel therapeutic targets and treatment approaches in clinical practice.

Liver-inclusive intestinal transplantation results in decreased alloimmune-mediated rejection but increased infection

Background and aims

A co-transplanted liver allograft has been thought to protect other organs from rejection-mediated injury; however, detailed analyses of co-transplanted liver on intestinal allograft outcomes have not been conducted to date. The aim of the study was to compare immune-mediated injury, causes of graft failure and clinical outcomes between recipients who underwent either a liver-inclusive intestinal transplant (LITx) or liver-exclusive intestinal transplant (LETx).

Methods

Between May 2000 and May 2010, 212 adult patients undergoing LITx (n =76) and LETx (n =136) were included. LITx underwent either liver combined intestinal or full multivisceral transplantation. LETx underwent either isolated intestinal or modified multivisceral transplantation.

Results

During 44.9 ± 31.4 months of follow-up, death-censored intestinal graft survival was significantly higher for LITx than LETx (96.9%, 93.2% and 89.9% vs 91.4%, 69.3% and 60.0% at 1, 3 and 5 years; p =0.0001). Incidence of graft loss due to rejection was higher in LETx than in LITx (30.9% vs 6.6%; p <0.0001), while infection was the leading cause of graft loss due to patient death in LITx (25.0% vs 5.1%; p <0.0001). Despite similar immunosuppression, the average number (0.87 vs 1.42, p =0.02) and severity of acute cellular rejection episode (severe grade: 7.9% vs 21.3%; p =0.01) were lower in LITx than in LETx. Incidence of acute antibody-mediated rejection was also significantly lower in LITx than in LETx (3.6% vs 15.2%; p =0.03). Incidence of chronic rejection was reduced in LITx (3.9% vs 24.3%; p =0.0002).

Conclusions

Intestinal allografts with a liver component appear to decrease risk of rejection but increase risk of infection. Our findings emphasize that LITx has characteristic immunologic and clinical features. Lower immunosuppression may need to be considered for patients who undergo LITx to attenuate increased risk of infection.

Pediatric intestinal transplantation

The field of intestinal transplantation has experienced dramatic growth since the first reported cases 3 decades ago. Improvements in operative technique, donor assessment and immunosuppressive protocols have afforded children who suffer from life-threatening complications of intestinal failure a chance at long-term survival. As experience has grown, newer diseases, with more systemic manifestations have arisen as potential indications for transplant. After discussing the historical developments of intestinal transplant as a backdrop, this review focuses on the specific pre-operative indications for transplant as well as the great success that intestinal rehabilitation has witnessed over the past decade. A detailed discussion of evolution of immunosuppressive strategies is followed a general review of the common infectious complications experienced by children after intestinal transplant as well as the current long- and short-term results, including a section on new research on the quality of life in this challenging population of patients.

Current status of intestinal and multivisceral transplantation

Clinical-nutritional autonomy is the ultimate goal of patients with intestinal failure (IF). Traditionally, patients with IF have been relegated to lifelong parenteral nutrition (PN) once surgical and medical rehabilitation attempts at intestinal adaptation have failed. Over the past two decades, however, outcome improvements in intestinal transplantation have added another dimension to the therapeutic armamentarium in the field of gut rehabilitation. This has become possible through relentless efforts in the standardization of surgical techniques, advancements in immunosuppressive therapies and induction protocols and improvement in postoperative patient care. Four types of intestinal transplants include isolated small bowel transplant, liver-small bowel transplant, multivisceral transplant and modified multivisceral transplant. Current guidelines restrict intestinal transplantation to patients who have had significant complications from PN including liver failure and repeated infections. From an experimental stage to the currently established therapeutic modality for patients with advanced IF, outcome improvements have also been possible due to the introduction of tacrolimus in the early 1990s. Studies have shown that intestinal transplant is cost-effective within 1-3 years of graft survival compared with PN. Improved survival and quality of life as well as resumption of an oral diet should enable intestinal transplantation to be an important option for patients with IF in addition to continued rehabilitation. Future research should focus on detecting biomarkers of early rejection, enhanced immunosuppression protocols, improved postoperative care and early referral to transplant centers.

Allograft biopsy findings in patients with small bowel transplantation

In this study, we sought to determine the incidence of post-transplant complications including acute cellular rejection (ACR), infection, and post-transplant lymphoproliferative disease (PTLD) in mucosal allograft biopsies in patients with small bowel transplant at our institution. We retrospectively reviewed pathology reports from 5675 small bowel allograft biopsies from 99 patients and analyzed the following: indications for biopsy, frequency and grade of ACR, the presence of infectious agents, results of workup for potential PTLD, results of C4d immunohistochemistry (IHC), features of chronic mucosal injury, and findings in concurrent native bowel biopsies. Findings from 42 allograft resection specimens were also correlated with prior biopsy findings. Indeterminate, mild, moderate, and severe ACR were seen in 276 (4.9%), 409 (7.2%), 100 (1.8%), and 207 (3.6%) of biopsies, respectively. Although ACR may show histologic overlap with mycophenolate mofetil toxicity, we found the analysis of concurrent native bowel biopsies to be helpful in this distinction. Adenovirus was the most common infectious agent seen (11%), and we routinely performed adenovirus IHC on biopsies. Eighteen patients (18%) developed PTLD, 83% of which were EBV associated, but only 28% of PTLD cases were diagnosed on mucosal allograft biopsies. C4d IHC did not correlate with the presence of donor-specific antibodies in limited cases.

Intestinal Failure: Adaptation, Rehabilitation, and Transplantation

Intestinal failure (IF) is a state in which the nutritional demands are not met by the gastrointestinal absorptive surface. A majority of IF cases are associated with short-bowel syndrome, which is a result of malabsorption after significant intestinal resection for numerous reasons, some of which include Crohn's disease, vascular thrombosis, and radiation enteritis. IF can also be caused by obstruction, dysmotility, and congenital defects. Recognition and management of IF can be challenging, given the complex nature of this condition. This review discusses the management of IF with a focus on intestinal rehabilitation, parenteral nutrition, and transplantation.

Infectious Complications Following Small Bowel Transplantation

Microbiological spectrum and outcome of infectious complications following small bowel transplantation (SBT) have not been thoroughly characterized. We performed a retrospective analysis of all patients undergoing SBT from 2004 to 2013 in Spain. Sixty-nine patients underwent a total of 87 SBT procedures (65 pediatric, 22 adult). The median follow-up was 867 days. Overall, 81 transplant patients (93.1%) developed 263 episodes of infection (incidence rate: 2.81 episodes per 1000 transplant-days), with no significant differences between adult and pediatric populations. Most infections were bacterial (47.5%). Despite universal prophylaxis, 22 transplant patients (25.3%) developed cytomegalovirus disease, mainly in the form of enteritis. Specifically, 54 episodes of opportunistic infection (OI) occurred in 35 transplant patients. Infection was the major cause of mortality (17 of 24 deaths). Multivariate analysis identified retransplantation (hazard ratio [HR]: 2.21; 95% confidence interval [CI]: 1.02-4.80; p = 0.046) and posttransplant renal replacement therapy (RRT; HR: 4.19; 95% CI: 1.40-12.60; p = 0.011) as risk factors for OI. RRT was also a risk factor for invasive fungal disease (IFD; HR: 24.90; 95% CI: 5.35-115.91; p < 0.001). In conclusion, infection is the most frequent complication and the leading cause of death following SBT. Posttransplant RRT and retransplantation identify those recipients at high risk for developing OI and IFD.

Risks and Epidemiology of Infections After Intestinal Transplantation

Intestinal transplantation has become a well-accepted and successful procedure to save the lives of patients suffering from intestinal failure and who have developed life-threatening complications of parenteral nutrition. Advances in all aspects of care, from the role of multidisciplinary intestinal rehabilitation services prior to transplant to the development strategies for early recognition of infectious sequelae and even the increasing availability of preventive strategies, have led to improved outcomes and a dramatic decline in infection-associated morbidity and mortality in children undergoing intestinal transplantation. Improvements in surgical techniques and immunosuppressive regimens have been essential components in these improvements, reducing risk of infection through reduction of technical complications and more optimal immunosuppression regimens. In addition, the development of molecular tools for early recognition of viral pathogens and an understanding of the timing and risks for infection have allowed for earlier and more successful treatments. Despite these improvements, infectious sequelae remain an important problem in this population, and additional efforts are needed to further minimize the risk of infectious sequelae in those children requiring this procedure.

Incidence of bloodstream infections in small bowel transplant recipients receiving selective decontamination of the digestive tract: A single-center experience

Pediatric patients undergoing small bowel transplantation are susceptible to postoperative CLABSI. SDD directed against enteric microbes is a strategy for reducing CLABSI. We hypothesized that SDD reduces the frequency of CLABSI, infections outside the bloodstream, and allograft rejection during the first 30 days following transplant. A retrospective chart review of 38 pediatric small bowel transplant recipients at CCHMC from 2003 to 2011 was conducted. SDD antimicrobials were oral colistin, tobramycin, and amphotericin B. The incidence of CLABSI, infections outside the bloodstream, and rejection episodes were compared between study periods. The incidence of CLABSI did not differ between study periods (6.9 CLABSI vs. 4.6 CLABSI per 1000 catheter days; p = 0.727), but gram positives and Candida predominated in the first 30 days. Incidence of bacterial infections outside the bloodstream did not differ (p = 0.227). Rejection occurred more frequently during the first month following transplant (p = 0.302). SDD does not alter the incidence of CLABSI, bacterial infections outside the bloodstream, or allograft rejection in the immediate 30 days post-transplantation. However, SDD does influence CLABSI organism types (favoring gram positives and Candida) and Candidal infections outside the bloodstream.

Bacterial translocation in adult small bowel transplantation

The application of intestinal transplantation is limited by the high rate of infectious complications that can occur; the migration of enteric microorganisms to extraintestinal sites (bacterial translocation) has been suggested to be responsible for this event. We reviewed 95 intestinal biopsies performed on 28 transplanted patients to identify histologic features predictive of isolation of enteric microorganisms in extraintestinal sites within the first month after transplantation. At least 1 isolation of enteric microorganisms in the peritoneal cavity and/or in blood samples was obtained in 13 patients (46.4%); this event led to higher 1-year mortality (38.5% vs. 6.7%; P = .041). Of the 95 biopsies, 38 were followed by positive cultures (40.0%), showing higher degrees of mucosal vascular alterations (Ruiz grade) and ischemia/reperfusion injuries (Park/Chiu grade) compared with the negative cases (P < .05). We also observed an higher prevalence of positive cultures in relation to acute cellular rejection episodes (P = .091). Neither clinical or surgical factors nor immunosuppressive therapy were observed to be significantly related to positive cultures. Histologic alterations of the small bowel allograft are related to isolation of enteric microorganisms in extraintestinal sites. The degree of these histologic features can identify patients at high risk of potentially life-threatening infectious complications and death.

Small bowel transplantation

BACKGROUND

Small bowel transplantation evolution, because of its complexity, was slower than other solid organs. Several advances have enabled its clinical application.

AIM

To review intestinal transplantation evolution and its current status.

METHOD

Search in MEDLINE and ScIELO literature. The terms used as descriptors were: intestinal failure, intestinal transplantation, small bowel transplantation, multivisceral transplantation. Were analyzed data on historical evolution, centers experience, indications, types of grafts, selection and organ procurement, postoperative management, complications and results.

CONCLUSION

Despite a slower evolution, intestinal transplantation is currently the standard therapy for patients with intestinal failure and life-threatening parenteral nutrition complications. It involves some modalities: small bowel transplantation, liver-intestinal transplantation, multivisceral transplantation and modified multivisceral transplantation. Currently, survival rate is similar to other solid organs. Most of the patients become free of parenteral nutrition.

Cochlear implantation in a patient with combined renal and liver transplantation

OBJECTIVE AND IMPORTANCE

Patients who have undergone solid organ transplantation and continuing immunosuppressant medication are at a higher risk of wound problems and infections following cochlear implantation. This risk is theoretically even further increased in multi-organ transplant recipients due to the increased doses of immunosuppressive medications that these patients are administered.

CLINICAL PRESENTATION AND INTERVENTION

Here, we present the first reported case of successful cochlear implantation in a patient who had previously undergone successful combined liver and kidney transplant. She had no significant complications from the surgery and had good audiological outcomes 3 months post-operatively.

CONCLUSION

As we continue our advances in the use of cochlear implant technology, our report adds to the growing evidence of its benefits in transplant recipients. However, there are important pre- and peri-operative considerations in this group of patients which can improve safety and outcome.

Neurologic aspects of multiple organ transplantation

Complex multiorgan failure may require simultaneous transplantation of several organs, including heart-lung, kidney-pancreas, or multivisceral transplantation. Solid organ transplantation can also be combined with hematopoietic stem cell transplantation to modulate immunologic response to a solid organ allograft. Combined multiorgan transplantation may offer a lower rate of allograft rejection and lower immunosuppression needs. In recent years, intestinal and multivisceral transplantations became viable as a rescue treatment for patients with irreversible intestinal failure who can no longer tolerate total parenteral nutrition with 70% survival after 5 years which is comparable to other types of solid organ allografts. Post-transplant neurologic complications were reported in up to 86% of allograft recipients and greatly overlap in intestinal and multivisceral allograft recipients, without a significant effect on the outcome of transplantation. Other common organ combinations in multiorgan transplantation include kidney-pancreas, which is mostly used for patients with renal failure and uncontrolled diabetes, and heart-lung for patients with congenital heart disease and idiopathic pulmonary arterial hypertension. Kidney-pancreas transplantation frequently results in an improvement of diabetic complications, including diabetic neuropathy. Heart-lung allograft recipients have very similar clinical course and spectrum of neurologic complications to lung transplant recipients. At this time there are no reports of an increased risk of graft-versus-host disease with combined transplantation of solid organ allograft and hematopoietic stem cells. Chronic immunosuppression and complex toxic-metabolic disturbances after multiorgan transplantation create a permissive environment for development of a wide spectrum of neurologic complications which largely resemble complications after transplantations of individual components of complex multiorgan allografts.

Infection among adult small bowel and multivisceral transplant recipients in the 30-day postoperative period

BACKGROUND

Intestinal transplantation is a potential option for patients with short gut syndrome (SGS), and infection is common in the postoperative period. The aim of our study was to identify the incidence and characteristics of bacterial and fungal infections of adult small bowel or multivisceral (SB/MV) transplantation recipients in the 30-day postoperative period.

METHODS

This retrospective chart review assessed the incidence and characteristics of bacterial and fungal infections in patients who underwent SB/MV transplant at our center between April 2004 and November 2008. Patient data were retrieved from computerized databases, flow-charts, and medical records.

RESULTS

A total of 40 adult patients with a mean age of 38.7 ± 13.4 years received transplants during this period: 27 patients received isolated SB, 12 received MV, and 1 received SB and kidney. Our immunosuppressive regimen included basiliximab for induction, and tacrolimus, sirolimus, and methylprednisolone for maintenance therapy. The most common indications for transplant were SGS, intestinal ischemia, Crohn's disease, trauma, motility disorders, and Gardner's syndrome. We report a 30-day postoperative infection rate of 57.5% and mean time to first infection of 10.78 ± 8.99 days. A total of 36 infections were documented in 23 patients. Of patients who developed infections, 56.5% developed 1 infection, 30.4% developed 2 infections, and 13% developed 3 infections. The most common site of infection was the abdomen, followed by blood, urine, lung, and wound infection. The isolates were gram-negative bacteria in 49.3%, gram-positive bacteria in 39.4%, and 11.3% were fungi. The most common organisms were Pseudomonas (19%), Enterococcus (15%), and Escherichia coli (13%). Overall, 47% of infections were due to drug-resistant pathogens; 31% of E. coli and Klebsiella species were extended-spectrum beta-lactamase-producing organisms, 36% of Pseudomonas was multidrug resistant (MDR), 75% of Enterococcus was vancomycin resistant, and 100% of Staphylococcus aureus was methicillin resistant.

CONCLUSION

These findings demonstrate that bacterial and fungal infections remain an important complication in SB/MV transplant recipients within the early postoperative period. Infections due to MDR organisms have emerged as an important clinical problem in this patient population.

Invasive fungal infections in solid organ transplant recipients

Invasive fungal infections are a major problem in solid organ transplant (SOT) recipients. Overall, the most common fungal infection in SOT is candidiasis, followed by aspergillosis and cryptococcosis, except in lung transplant recipients, where aspergillosis is most common. Development of invasive disease hinges on the interplay between host factors (e.g., integrity of anatomical barriers, innate and acquired immunity) and fungal factors (e.g., exposure, virulence and resistance to prophylaxis). In this article, we describe the epidemiology and clinical features of the most common fungal infections in organ transplantation. Within this context, we review recent advances in diagnostic modalities and antifungal chemotherapy, and their impact on evolving prophylaxis and treatment paradigms.

[Risk factors for cytomegalovirus in solid organ transplant recipients]

Cytomegalovirus (CMV) is the most important opportunistic pathogen in patients undergoing solid organ transplantation and increases mortality due to both direct and indirect effects. The most important risk factor for the development of CMV disease is discordant donor-recipient CMV serology (positive donor and negative recipient), which confers more than 50% risk of developing CMV disease if no prophylaxis is given. The use of highly potent antiviral agents for CMV prophylaxis in high-risk patients has changed the characteristics of CMV disease in this population. Other classical risk factors for CMV disease include acute graft rejection, the type of organ transplanted, coinfection with other herpesviruses and the type of immunosuppressive agents employed. New risk factors for this complication have recently been described, including variations in the CMV genotype between donor and recipient and genetic alterations in the recipient's innate immunity. The present review discusses classical risk factors and the latest findings reported on the development of CMV in organ transplant recipients.

Small-Bowel Allograft Biopsies in the Management of Small-Intestinal and Multivisceral Transplant Recipients: Histopathologic Review and Clinical Correlations

Context.—Intestinal transplant has become a standard treatment option in the management of patients with irreversible intestinal failure. The histologic evaluation of small-bowel allograft biopsy specimens plays a central role in assessing the integrity of the graft. It is essential for the management of acute cellular and chronic rejection; detection of infections, particularly with respect to specific viruses (cytomegalovirus, adenovirus, Epstein-Barr virus); and immunosuppression-related lymphoproliferative disease.

Objective.—To provide a comprehensive review of the literature and illustrate key histologic findings in small-bowel biopsy specimen evaluation of patients with small-bowel or multivisceral transplants.

Data Sources.—Literature review using PubMed (US National Library of Medicine) and data obtained from national and international transplant registries in addition to case material at Columbia University, Presbyterian Hospital, and Mount Sinai Medical Center, New York, New York.

Conclusions.—Key to the success of small-bowel transplantation and multivisceral transplantation are the close monitoring and appropriate clinical management of patients in the posttransplant period, requiring coordinated input from all members of the transplant team with the integration of clinical, laboratory, and histopathologic parameters.

Disseminated candidiasis developing during prophylaxis with fluconazole in a small-intestine transplant recipient

A 31-year-old man underwent immunosuppressive treatment and was treated with 150 mg per day of prophylactic oral fluconazole after receiving a small-intestine transplant. The patient had acute rejection by the end of the first week after the transplant. Endoscopic examination showed white plaques. In blood and urine cultures, growth of Candida albicans was detected. Biopsy specimens showed high levels of conidia and hyphae in all regions. Intravenous treatment with caspofungin was started for the patient. Candidal findings had regressed on follow-up endoscopy. However, the patient died 3 months after transplant because of the effects of immunosuppression on his bone marrow and the development of disseminated intravascular coagulation. Candida species are the most common cause of invasive fungal infections that develop after solid-organ transplant. Following transplant, candidemia may develop during systemic antifungal treatment with a high level of mortality.

Risk factors and outcomes of Staphylococcus aureus infections after small bowel and multivisceral transplantation

BACKGROUND

No studies have evaluated the risk factors and outcomes of Staphylococcus aureus (SA) infections in small bowel (SBT) and multivisceral (including small bowel) transplantation (MVT).

METHODS

SBT and MVT recipients with SA infections (22 cases) were retrospectively identified and compared with matched non-SA-infected recipient controls (44). The characteristics were compared with Friedman and Cochran-Mantel-Haenszel tests. Conditional logistic regression analysis was performed to identify risk factors, and Kaplan-Meier curve and Cox proportional hazard model were performed for survival analysis.

RESULTS

The median age was 2.07 years (range, 0.76-54.04). Forty-three percent of the first SA infections were bloodstream infections, 30% lung infections, and 26% surgical site infections; 36% of these isolates were methicillin-resistant SA. Median time (days) to surgical site infections (41.0; range, 0-89) was significantly shorter than that to lung infections (266; range, 130-378) (P = 0.01). By univariate analysis, it was found that cases were more likely to have cytomegalovirus (CMV) sero-mismatch (odds ratio [OR] = 3.03 [95% confidence interval, 0.88-10.43]; P = 0.08), and controls were more likely to receive mycophenolate mofetil (MMF) treatment (0.09 [0.001-0.82]; P = 0.03). By multivariable analysis, patients with CMV sero-mismatch were found to have higher odds of developing SA infection (OR, 2.92; P = 0.085), whereas MMF had a protective effect (OR, 0.08; P = 0.031), adjusting for matched criteria. SA cases had shorter survival than controls (mean survival, 28.5 vs. 45.8 months [P = 0.04]) and were 2.18 times more likely to die (1.02-4.67, P = 0.04).

CONCLUSIONS

SA infections were associated with a significant shorter survival time and higher risk of death. The presence of CMV sero-mismatch and the absence of MMF treatment were found to be the risk factors for SA infections after SBT and MVT.

Six-month incidence of bloodstream infections in intestinal transplant patients

BACKGROUND

Intestinal transplantation has emerged as an established treatment for life-threatening intestinal failure. The most common complication and cause of death is infection. Risk of infection is highest during the first 6 months, as a consequence of maximal immunosuppression, greater than that required for any other organ allograft.

METHODS

We performed a retrospective chart review of all (56) adult and pediatric (<18 years) small bowel transplant patients at our institution between November 2003 and July 2007, and analyzed the 6-month post-transplant incidence of bloodstream infections (BSIs). We evaluated multiple risk factors, including inclusion of a colon or liver, total bilirubin >5, surgical complications, and acute rejection.

RESULTS

A BSI developed in 34 of the 56 patients, with a total of 85 BSI episodes. Of these BSI episodes, 65.9% were due to gram-positive organisms, 34.1% gram-negative organisms, and 2.4% due to fungi. The most common isolates were Enterococcus species, Enterobacter species, Klebsiella species, and coagulase-negative staphylococci. Inclusion of the liver and/or a preoperative bilirubin >5 mg/dL appeared to increase the incidence of BSI (P = 0.0483 and 0.0005, respectively). Acute rejection and colonic inclusion did not appear to affect the incidence of BSI (P = 0.9419 and 0.8248, respectively). The BSI incidence was higher in children (P = 0.0058).

CONCLUSIONS

BSIs are a common complication of intestinal transplantation. Risk factors include age <18, inclusion of the liver, and pre-transplant bilirubin >5. Acute rejection and colon inclusion do not appear to be associated with increased BSI risk.

Histologic features of cytomegalovirus enteritis in small bowel allografts

BACKGROUND

Cytomegalovirus (CMV) is one of the most common viral infections to affect solid organ transplant patients, most frequently owing to reactivation of a latent infection as a result of immunosuppression. CMV enteritis (CE) may enter into the differential diagnosis of acute rejection in biopsies of small bowel (SB) allografts, where differentiation is important due to disparate therapies.

OBJECTIVE

The aim of this study was to identify histologic features in SB allografts that may suggest CE.

METHODS

The case files for a single institution were queried for all cases of SB mucosal biopsies with cells positive by CMV immunoperoxidase staining. Morphologic and clinical information was reviewed.

RESULTS

Six biopsies demonstrating immunoperoxidase-confirmed CE were identified in a retrospective review of the records of a single institution. A common predisposing factor was the administration of high-dose steroids within a month before CE diagnosis. Most cases (66%) displayed a demarcated area of villous/crypt loss with an abundance of plasma cells and lymphocytes and a paucity of eosinophils. One case showed an acute enteritis-like pattern of injury, corresponding with a higher number of CMV-positive cells. CMV inclusions were visible on hematoxylin-eosin stains in all but 1 case. In no case were histologic criteria for acute cellular rejection met.

CONCLUSIONS

The presence of circumscribed area of mucosal injury with few eosinophils or an acute enteritis pattern should prompt the identification of viral inclusions or the acquisition of a CMV immunostain.

Quality of surgical care in liver and small-bowel transplant: approach to risk assessment and antibiotic prophylaxis

In August 2002, The Centers for Medicare and Medicaid Services and the Centers for Disease Control and Prevention implemented the National Surgical Infection Prevention project. The goal of the project was to decrease the morbidity and mortality associated with postoperative surgical site infections through appropriate selection and timing of administration and discontinuation of prophylactic antimicrobials. The National Surgical Infection Prevention project, however, excluded transplant surgeries from its focus because of the lack of randomized clinical trials comparing antimicrobial agents. The goals of this article are to (1) provide a framework for risk factors associated with surgical site infections in liver, small-bowel, and multivisceral transplants; (2) review general principles of the appropriate antimicrobial prophylaxis; (3) provide a framework for developing a triage of liver, small-bowel, and multivisceral transplant candidates for appropriate antibiotic prophylaxis; and (4) develop an approach to further quality improvements in transplant surgical care. A multidisciplinary team produced recommendations for antibacterial prophylaxis and monitoring.

Quality of Surgical Care in Liver and Small-Bowel Transplant: Approach to Risk Assessment and Antibiotic Prophylaxis

In August 2002, The Centers for Medicare and Medicaid Services and the Centers for Disease Control and Prevention implemented the National Surgical Infection Prevention project. The goal of the project was to decrease the morbidity and mortality associated with postoperative surgical site infections through appropriate selection and timing of administration and discontinuation of prophylactic antimicrobials. The National Surgical Infection Prevention project, however, excluded transplant surgeries from its focus because of the lack of randomized clinical trials comparing antimicrobial agents. The goals of this article are to (1) provide a framework for risk factors associated with surgical site infections in liver, small-bowel, and multivisceral transplants; (2) review general principles of the appropriate antimicrobial prophylaxis; (3) provide a framework for developing a triage of liver, small-bowel, and multivisceral transplant candidates for appropriate antibiotic prophylaxis; and (4) develop an approach to further quality improvements in transplant surgical care. A multidisciplinary team produced recommendations for antibacterial prophylaxis and monitoring.

Infectious complications in pediatric liver transplantation candidates

We analyzed infections that occurred within one month prior to LT, identified factors associated with their occurrence and effect of infections on post-transplant mortality. The study group included 40 consecutive children who underwent LT. Sites and types of infection and culture results were recorded prospectively. IID was assessed. Risk factors for the infectious events were analyzed. Forty infection episodes were found in 24 patients (60%); 90% were bacterial, 7.5% fungal, and 2.5% viral. Overall, IID was 38.2 per 1000 patient days. Sites of bacterial infection were urinary tract in 13 events (36.1%) and blood stream in 11 events (30.5%). Bacteremia (culture positive infection episodes) was identified in 19 events (52.7%). Gram-negative isolates were twice as frequent as Gram-positive infections (63.1% vs. 36.9%). Risk factors for the infectious complications were young age, low body weight, prior abdominal surgery, chronic liver disease related to biliary problems, presence of ascites, portal hypertension and cirrhosis, and high PELD score (p < 0.05 for all). Infectious complications in pediatric LT candidates are common. Preventive measures are important not only to reduce the infectious complications but also to prevent the post-operative mortality.