Renal artery aneurysm secondary to Candida albicans in four kidney allograft recipients

Diagnosing and Managing Urinary Tract Infections in Kidney Transplant Recipients

In the article, the authors review antibiotic treatment options for both acute uncomplicated UTI and complicated UTI. In addition, they review alternative regimens which are needed in the setting of drug-resistant pathogens including vancomycin-resistant Enterococcus, -extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-E), carbapenem-resistant Enterobacterales, and carbapenem-resistant Pseudomonas, which are encountered with more frequency.

Clinical impact of preservation fluid contamination on kidney transplant patients

BACKGROUND

Kidney transplantation is associated with a high risk of infectious complications due to immunosuppressive therapy. Although infections may be transmitted from donor to transplant recipient through contaminated preservation solution (PS), the clinical impact of this is not well-understood.

METHODS

We retrospectively evaluated PS contamination rates in a series of 339 patients who underwent cadaveric renal transplant at our centre. All patients with a positive culture received targeted preemptive therapy (PET).

RESULTS

Of the 339 PS samples, 136 (40.1%) were positive for a microorganism, mainly coagulase-negative staphylococci (CoNS; n = 89;60.5%), gram-negative bacilli (n = 31;21.1%), non-CoNS gram-positive cocci (n = 18;12.2%), and Candida spp (n = 2;1.4%). Of the 136 positive cases, 42 (30.9%) received PET (12.4% of the cohort). No cases of urinary tract infection, surgical site infection, or graft loss were observed. Overall, our findings indicate that PS contamination, mainly by saprophytic skin flora (CoNS) is common. Only 8% of patients required antibiotic or antifungal therapy.

CONCLUSION

The infection transmission rate from donors to recipients was negligible (0%), perhaps due to the early initiation of a targeted PET after isolation of a recognized pathogen. More data from large, prospective studies are needed to confirm these findings.

The impact of preservation fluid culture on graft site arteritis: A systematic review and meta-analysis

BACKGROUND

The role of culturing the graft preservation fluid (PF) is controversial and its impact on graft arteritis development remains unclear.

METHODS

Systematic literature search retrieving observational studies comparing solid organ transplant (SOT) recipients with culture-positive PF versus culture-negative PF. The quality of included studies was independently assessed according to the ROBINS-I tool for observational studies. Meta-analysis was performed using Mantel-Haenszel random-effect models. Graft site arteritis within 180 days from transplant was selected as the primary outcome.

RESULTS

Twenty-one observational studies (N = 2208 positive PF vs. 4458 negative) were included. Among positive PF, 857 (38.8%) were classified as high-risk group pathogens and 1351 (61.2%) as low-risk pathogens. Low-risk and negative PF showed similar odds ratios. A significant higher risk of graft arteritis was found in SOT recipients with a PF yielding a high-risk pathogen (odds ratio [OR] 18.43, 95% confidence interval [CI] 7.83-43.40) compared to low-risk and negative PF, with low heterogeneity (I² = 2.24%). Similar results were found considering separately high-risk bacteria (OR 12.02, 95%CI 4.88-29.60) and fungi (OR 71.00, 95%CI 28.07-179.56), with no heterogeneity (I² = 0%), and in the subgroup analyses of the liver (OR 16.78, 95%CI 2.95-95.47) and kidney (OR 19.90, 95%CI 4.78-82.79) recipients. However, data about diagnostic features of graft arteritis were very limited, indeed for only 11 of the 93 events histological or microbiological results were reported.

CONCLUSIONS

Our results may support the performance of PF culturing and a preemptive diagnostic or therapeutic management upon isolation of high-risk pathogens. Further studies based on a reliable diagnosis of graft arteritis are needed.

Infective Artery Rupture of Renal Allografts: A Single-Center Retrospective Study in China

OBJECTIVE

This study investigated the composition of pathogenic microorganisms, clinical features, and therapeutic strategies of infective artery rupture of renal allografts in recipients receiving deceased donor (DD) kidneys.

METHODS

We retrospectively studied the clinical data of the DD kidney transplant recipients with donor-associated infection at Tongji Hospital, Wuhan, China from January 1, 2015 to December 31, 2018, related recipients and corresponding donors. We collected the entire results of pathogenic microorganisms cultured from these related ruptured kidneys and then analyzed their distribution and differences.

RESULTS

A total of 1440 kidney transplants from DD were performed in our center. The total incidence of infective artery rupture in kidney transplants was about 0.76% (11/1440), and the annual incidence ranged from 0.25% to 1.03%. The microbial culture results revealed that 11 recipients suffered from infective artery rupture and 3 recipients who accepted the kidney from same donor had the donor-associated pathogens, including 9 fungal strains (28.1%) and 23 bacterial strains (71.9%). There were 4 recipients infected with multi-drug-resistant Staphylococcus and Klebsiella pneumoniae from the above 11 recipients, of which, 10 recipients underwent graft loss, and one died of septic shock. The microbial cultures of the remaining 3 recipients who received appropriate anti-infective regimens turned negative eventually, and the patients were discharged successfully without significant complications.

CONCLUSION

Renal recipients with infections derived from DDs were at high risk of artery rupture, graft loss, or even death. Appropriate anti-infective treatment is essential to reduce the incidence of artery rupture and mortality.

Renal artery infectious (mycotic) pseudoaneurysms in renal transplantation recipients

INTRODUCTION

Infection of the artery at or around the anastomotic site is an ominous complication commonly presenting as a leak and/or local dissolution of the arterial wall.

MATERIAL AND METHODS

Narrative review based on relevant PubMed, EMBASE, and Scielo indexed English or Spanish-written articles for the period January 2000-December 2019. A pooled analysis regarding etiology was performed. Based on the results obtained with this approach, a diagnostic/therapeutic algorithm is suggested in order to optimize its clinical management.

FINDINGS

Arterial pseudoaneurysms are pseudocapsuled contained hematomas generated as the result of an arterial leaking. They are infrequent (<1% of cases), mostly related with infection (contamination of preservation fluid or sepsis) and located at the arterial anastomotic site in renal transplantation recipients. Although they are frequently diagnosed in symptomatic patients days/weeks after transplantation, they may remain unnoticed for long periods being diagnosed incidentally. Color coded-Doppler ultrasound confirms the clinical suspicion. Angio CT-scan and angiography are used for surgical planning or endovascular treatment, respectively. The etiological diagnosis is made on a basis of excised tissue culture. The decision-making process regarding the treatment approach, mostly relies on clinical presentation and anatomical location. Therapeutic options include ultrasound-guided percutaneous thrombin injection, endovascular treatment, and surgery.

CONCLUSIONS

Mycotic pseudoaneurysms in renal transplantation recipients may pose a significant challenge in cases of spontaneous rupture, given the risk for massive bleeding and death. Adequate management requires accurate diagnosis. Early endovascular stenting remains the treatment of choice in hemodynamically unstable patients. Percutaneous injection and vascular reconstruction present variable success rates in preserving graft function.

Renal artery infectious (mycotic) pseudoaneurysms in renal transplantation recipients

INTRODUCTION

Infection of the artery at or around the anastomotic site is an ominous complication commonly presenting as a leak and/or local dissolution of the arterial wall.

MATERIAL AND METHODS

Narrative review based on relevant PubMed, EMBASE, and Scielo indexed English or Spanish-written articles for the period January 2000-December 2019. A pooled analysis regarding etiology was performed. Based on the results obtained with this approach, a diagnostic/therapeutic algorithm is suggested in order to optimize its clinical management.

FINDINGS

Arterial pseudoaneurysms are pseudocapsuled contained hematomas generated as the result of an arterial leaking. They are infrequent(<1% of cases),mostly related with infection(contamination of preservation fluid or sepsis) and located at the arterial anastomotic site in renal transplantation recipients. Although they are frequently diagnosed in symptomatic patients days/weeks after transplantation, they may remain unnoticed for long periods being diagnosed incidentally. Color coded-Doppler ultrasound confirms the clinical suspicion. Angio CT-scan and angiography are used for surgical planning or endovascular treatment, respectively. The etiological diagnosis is made on a basis of excised tissue culture. The decision-making process regarding the treatment approach, mostly relies on clinical presentation and anatomical location. Therapeutic options include ultrasound-guided percutaneous thrombin injection, endovascular treatment, and surgery.

CONCLUSIONS

Mycotic pseudoaneurysms in renal transplantation recipients may pose a significant challenge in cases of spontaneous rupture, given the risk for massive bleeding and death. Adequate management requires accurate diagnosis. Early endovascular stenting remains the treatment of choice in hemodynamically unstable patients. Percutaneous injection and vascular reconstruction present variable success rates in preserving graft function.

Endocarditis in kidney transplant recipients: a systematic review

Infective Endocarditis (IE) carries significant mortality. Bacteremia, which is a predisposing factor for IE, occurs more frequently in immunocompromised individuals. Interestingly, IE in kidney transplant recipients has not been adequately described. The aim of this study was to systematically review all published cases of IE in kidney transplant recipients and describe their epidemiology, microbiology, clinical characteristics, treatment and outcomes. A systematic review of PubMed (through 13^th December 2019) for studies providing epidemiological, clinical, microbiological as well as treatment data and outcomes of IE in kidney transplant recipients was performed. A total of 60 studies, containing data of 117 patients, were included in the analysis. The most common causative pathogens were gram-positive microorganisms in 57.4%, gram-negative microorganisms in 14.8%, fungi in 20%, while in 18.9% of cases, IE was culture-negative. Aortic valve was the most commonly infected valve followed by mitral, tricuspid and the pulmonary valve. Diagnosis was set with a transthoracic ultrasound in half the cases, followed by transesophageal ultrasound and autopsy. Fever was present in most cases, while embolic phenomena were noted in two out of five cases. Aminoglycosides, cephalosporins and aminopenicillins were the most commonly used antimicrobials, and surgical management was performed in one out of three cases. Clinical cure was noted in 60.9%, while overall mortality was 45.3%. To conclude, this systematic review thoroughly describes IE in kidney transplant recipients and provides information on epidemiology, clinical presentation, treatment and outcomes. Moreover, it identifies the emerging role of Enterococci, gram-negatives and fungi in IE in this population.

Fungal endocarditis in transplant recipients: A systematic review

BACKGROUND

Invasive fungal infections remain a major cause of morbidity and mortality in transplant recipients. Moreover, Fungal Infective Endocarditis (FIE) is a rare infection that carries a higher mortality than bacterial IE in normal host, while in transplant recipients may be even higher. The purpose of this study was to systemically review all published cases of FIE in solid organ and allogeneic bone marrow transplant recipients, describe the epidemiology, microbiology, clinical characteristics, treatment and outcomes of these infections, and to identify risk factors for mortality by FIE.

METHODS

A systematic review of PubMed, Scopus and Cochrane Library (through 20 May 2020) for studies providing epidemiological, clinical, microbiological and treatment data and outcomes of FIE in transplant recipients was performed.

RESULTS

A total of 60 studies, containing data of 72 patients, were included. The most common transplants were those of the kidney and the liver, while the commonest causative pathogen was Aspergillus. Mitral valve was the commonest infected intracardiac site, followed by mural endocardium. Diagnosis was made with transthoracic echocardiography in 44.3%, while the diagnosis was made at autopsy in 37.3%. Embolic phenomena were the commonest clinical presentation, followed by fever, heart failure and endophthalmitis. Amphotericin B, voriconazole and caspofungin were the commonest antifungals used for treatment of FIE. Clinical cure was noted in 26.9%, while overall mortality was 78.6%. Amphotericin B or caspofungin use was negatively associated with overall mortality.

CONCLUSIONS

This systematic review thoroughly describes IE in transplant recipients and provides information on epidemiology, clinical presentation, treatment and outcomes.

Allograft artery mycotic aneurysm after kidney transplantation: A case report and review of literature

BACKGROUND

Allograft artery mycotic aneurysm (MA) represents a rare but life-threatening complication of kidney transplantation. Graftectomy is widely considered the safest option. Due to the rarity of the disease and the substantial risk of fatal consequences, experience with conservative strategies is limited. To date, only a few reports on surgical repair have been published. We describe a case of true MA successfully managed by aneurysm resection and arterial re-anastomosis.

CASE SUMMARY

An 18-year-old gentleman, on post-operative day 70 after deceased donor kidney transplantation, presented with malaise, low urinary output, and worsening renal function. Screening organ preservation fluid cultures, collected at the time of surgery, were positive for Candida albicans. Doppler ultrasound and contrast-enhanced computer tomography showed a 4-cm-sized, saccular aneurysm of the iuxta-anastomotic segment of the allograft artery, suspicious for MA. The lesion was wide-necked and extended to the distal bifurcation of the main arterial branch, thus preventing endovascular stenting and embolization. After multidisciplinary discussion, the patient underwent surgical exploration, aneurysm excision, and re-anastomosis between the stump of the allograft artery and the internal iliac artery. The procedure was uneventful. Histology and microbiology evaluation of the surgical specimen confirmed the diagnosis of MA caused by Candida infection. Three years after the operation, the patient is doing very well with excellent allograft function and no signs of recurrent disease.

CONCLUSION

Surgical repair represents a feasible option in carefully selected patients with allograft artery MA. Anti-fungal prophylaxis is advised when preservation fluid cultures are positive.

Urinary tract infections in solid organ transplant recipients: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These updated guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of urinary tract infections (UTI) in solid organ transplantation, focusing on kidney transplant (KT) recipients. KT recipients have unique risk factors for UTI, including indwelling stents and surgical manipulation of the genitourinary tract. KT recipients experience multi-drug antibiotic-resistant infections-UTI prevention and management strategies must consider risks of antimicrobial resistance. Non-antimicrobial prevention strategies for UTI in KT recipients are reviewed. It is important to recognize that some renal transplant recipients with UTI may primarily present with fever, malaise, leukocytosis, or a non-specific sepsis syndrome without symptoms localized to the urinary tract. However, asymptomatic bacteriuria (AB) must be distinguished from UTI because AB is not necessarily a disease state. Accumulating data indicate that there are no benefits of antibiotics for treatment of AB in KT recipients more than 2 months after post-transplant. Further research is needed on management of AB in the early (<2 months) post-transplant period, prophylaxis for UTI in this era of antibiotic resistance, recurrent UTI, non-antimicrobial prevention of UTI, and uropathogens identified in donor urine and/or preservative fluid cultures.

Successful repair of kidney graft artery rupture secondary to infection using a preprocessed homologous "Y"-shaped iliac artery

Objectives

This retrospective study aims to describe novel ways of repair kidney allograft artery rupture secondary to infection using a preprocessed homologous “Y”‐shaped iliac artery.

Methods

Five patients' whose course was complicated by graft arterial rupture were included in the rupture group, and patients who received the kidney from the same donor were included in the control group. In the rupture group, the iliac artery used for revascularization was harvested from a DCD donor, pre‐treated with absolute diethyl ether, followed by absolute alcohol, and then preserved in 75% alcohol. A biopsy of the arterial graft was obtained and stained using hematoxylin and eosin (H&E). Once a patient was diagnosed with kidney allograft arterial rupture by ultrasound, emergency surgery was conducted and the preprocessed “Y”‐shaped iliac artery was used for bridging.

Results

Five patents were included in the rupture group. The “Y”‐shaped iliac artery grafts were successfully preprocessed, H&E staining and electron microscope observation revealed few visible nuclei, with karyorrhexis and karyolysis. There were no significant differences in the long‐term graft survival between two groups.

Conclusions

In conclusion, using preprocessed homologous “Y”‐shaped iliac artery provides a useful method to bridge the vascular defects from kidney graft artery rupture secondary to infection in renal allograft recipients.

Candida sp. Infections in Patients with Diabetes Mellitus

Candidiasis has increased substantially worldwide over recent decades and is a significant cause of morbidity and mortality, especially among critically ill patients. Diabetes mellitus (DM) is a metabolic disorder that predisposes individuals to fungal infections, including those related to Candida sp., due to a immunosuppressive effect on the patient. This review aims to discuss the latest studies regarding the occurrence of candidiasis on DM patients and the pathophysiology and etiology associated with these co-morbidities. A comprehensive review of the literature was undertaken. PubMed, Scopus, Elsevier’s ScienceDirect, and Springer’s SpringerLink databases were searched using well-defined search terms. Predefined inclusion and exclusion criteria were applied to classify relevant manuscripts. Results of the review show that DM patients have an increased susceptibility to Candida sp. infections which aggravates in the cases of uncontrolled hyperglycemia. The conclusion is that, for these patients, the hospitalization periods have increased and are commonly associated with the prolonged use of indwelling medical devices, which also increase the costs associated with disease management.

Early renal arterial rupture and arterial pseudoaneurysm in graft kidneys from the same deceased donor

Vascular complications are serious problems after kidney transplantation. An aneurysm or rupture in a graft artery is a rare but potentially devastating complication, which may lead to renal function impairment, graft loss, or even death. In this paper, we present two rare vascular complications in the early postoperative course after renal transplantation from the same deceased donor. In the first case, a 49-year-old woman who had spontaneous graft arterial rupture 13 days after kidney transplantation presented with sudden distension in the right lower abdomen. In the second case, a 56-year-old woman recipient with a graft renal arterial pseudoaneurysm presented with decreased urine output and deteriorating renal function 32 days after transplantation. Immediate surgical repair was performed, and fibrin sealant was applied to strengthen the fragile renal arterial wall. Although the function of both graft kidneys recovered well after surgery, the first graft kidney was removed 2 months later because of repeated fungal and bacterial infections. Aggressive surgical reconstruction may preserve graft kidneys in patients with vascular complications after kidney transplantation, but recovery of the graft condition remains a demanding challenge in renal transplantation.

A novel technique for en bloc kidney transplantation from infant donors with extremely low body weight by using the distal abdominal aorta as an outflow tract

Pediatric kidney donors remain underutilized due to the high risk of postoperative thrombosis. To address this problem, we developed a novel en bloc kidney transplantation technique using donor thoracic aorta and the distal abdominal aorta as inflow and outflow tracts, respectively. Briefly, eight kidneys from deceased infant donors under five months old and with low body weight (1.9-4.9 kg) were transplanted en bloc into four pediatric and four adult patients. The donor's common iliac artery or external iliac artery was anastomosed to the recipient's distal external iliac artery or inferior epigastric artery, respectively, as an outflow tract. Recipients received basiliximab or antithymocyte globulin as induction therapy followed by tacrolimus, mycophenolate mofetil, and prednisone but without prophylactic anticoagulation. Delayed graft function was observed in one patient but was reversed at 90 days posttransplant. Two patients had urine leakage, which was cured by conservative treatment. Two recipients developed lung infections that eventually cleared. No patients experienced posttransplant vascular thrombosis. After 1-1.5 years of follow-up, all patients are well and have normal serum creatinine levels. In conclusion, this novel en bloc kidney transplantation technique using a modified arterial inflow and outflow tract can prevent vascular thrombosis and provide adequate graft function.

Mycotic aneurysm of the hepatic artery in pediatric liver transplantation: A case series and literature review

Mycotic aneurysm of the hepatic artery (HA) is a rare, unpredictable, and potentially lethal complication of liver transplantation (LT). Pediatric LT is not exempt from it but the related literature is rather scanty. We present our experience with post-LT mycotic aneurysm of the HA in pediatric age, describing four cases occurred with a special focus on the possible risk factors for its development and a proposal for the management of high-risk recipients.

Mycotic Pseudoaneurysm After Kidney Transplantation: Two Case Reports

BACKGROUND

Vascular complications after kidney transplantation may cause allograft loss. Here, we describe 2 patients with extrarenal mycotic pseudoaneurysm after kidney transplantation.

PATIENTS

Patient 1 was a 54-year-old man who developed pseudoaneurysm 60 days after transplantation, and patient 2 was a 48-year-old woman who was diagnosed with a pseudoaneurysm 5 months after transplantation.

RESULTS

Patient 1 had a deceased-donor kidney transplant with end-to-side external iliac arterial anastomosis that was reconstructed 8 days after transplantation owing to rupture and major bleeding. At 60 days after transplantation, he had high serum creatinine level and Doppler ultrasonography showed a pseudoaneurysm of the arterial graft anastomosis and postanastomotic renal artery stenosis. Treatment included surgical excision of the pseudoaneurysm, vascular reconstruction, and fluconazole, with mycologic culture of the resected pseudoaneurysm showing Candida albicans. Patient 2 developed nondisabling intermittent claudication at 5 months after kidney transplantation, with a pseudoaneurysm subsequently observed on Doppler ultrasonography and computerized tomographic angiography. Treatment included renal artery thrombectomy and common iliac bypass to the hilar donor renal artery with inverted ipsilateral long saphenous vein. Operative samples showed C albicans, and she was treated with fluconazole. Both patients had satisfactory outcomes, and both kidney allografts were preserved.

CONCLUSIONS

Extrarenal mycotic pseudoaneurysms after kidney transplantation require a high index of suspicion for early diagnosis, and preservation of the kidney graft may be achieved with the use of surgical treatment and antifungal therapy.

Fifty-one cases of fungal arteritis after kidney transplantation: A case report and review of the literature

Fungal arteritis affecting graft arteries is a rare but life-threatening complication in kidney transplantation (KT). Here, we report the case of a patient with Aspergillus arteritis who experienced renal artery rupture 8 days after KT. We also reviewed 50 other reported cases of fungal arteritis after KT. We found that fungal contamination can occur during kidney graft harvest, preservation, and/or transplantation. Typically, early diagnosis, timely antifungal treatment, and emergency surgery seem crucial for avoiding life-threatening vascular complications.

Candida endocarditis: systematic literature review from 1997 to 2014 and analysis of 29 cases from the Italian Study of Endocarditis

INTRODUCTION

Candida Endocarditis (CE) is a deadly disease. It is of paramount importance to assess risk factors for acquisition of both Candida native (NVE) and prosthetic (PVE) valve endocarditis and relate clinical features and treatment strategies with the outcome of the disease. Areas covered: We searched the literature using the Pubmed database. Cases of CE from the Italian Study on Endocarditis (SEI) were also included. Overall, 140 cases of CE were analyzed. Patients with a history of abdominal surgery and antibiotic exposure had higher probability of developing NVE than PVE. In the PVE group, time to onset of CE was significantly lower for biological prosthesis compared to mechanical prosthesis. In the whole population, greater age and longer time to diagnosis were associated with increased likelihood of death. Patients with effective anti-biofilm treatment, patients who underwent cardiac surgery and patients who were administered chronic suppressive antifungal treatment showed increased survival. For PVE, moderate active anti-biofilm and highly active anti-biofilm treatment were associated with lower mortality. Expert commentary: Both NVE and PVE could be considered biofilm-related diseases, pathogenetically characterized by Candida intestinal translocation and initial transient candidemia. Cardiac surgery, EAB treatment and chronic suppressive therapy might be crucial in increasing patient survival.

Infectious anastomotic pseudoaneurysm complicating renal allograft: case report and review of literature

Infectious anastomotic pseudoaneurysm complicating renal transplant is rare, but probably under-reported with <30 cases worldwide. We report a 45-year-old man with hypertension, diabetes mellitus and end stage renal failure, who had a renal transplant anastomosed to the right external iliac artery and vein. Postoperatively, he made a slow recovery with malaise and persistent vague right iliac fossa discomfort. Ultrasound scan 1 month postoperatively showed perinephric collection, and fluid culture grew Enterococcus faecium and Pseudomonas aeruginosa. He was started on vancomycin, daptomycin and colistin. MAG-3 scan also showed suboptimal function in the renal allograft. His symptoms persisted with fever, and blood culture yielded P. aeruginosa. Repeated ultrasound scan, and subsequent computed tomography scan a few weeks later, showed perinephric collection and a large, 3.8×3.5 cm pseudoaneurysm posteromedial to the graft kidney. He underwent emergency graft excision, together with resection of the pseudoaneurysm with in situ reversed great saphenous vein interposition graft, and made a good recovery on hemodialysis. The aneurysm wall grew P. aeruginosa, and he was put on imipenem and cilastatin (tienam), colistin, ciprofloxacin and daptomycin. To our knowledge, this is one of very few cases in the world’s literature in which a P. aeruginosa infectious anastomotic pseudoaneurysm developed after a renal allograft.

Candida arteritis in kidney transplant recipients: case report and review of the literature

Multi-organ procurement is a risk factor for contamination of preservation fluid with intestinal flora including fungi (e.g., Candida). Transmission of fungal species to the graft vessel can cause mycotic arteritis. This is a very rare but life-threatening complication of renal transplantation. We present 2 cases of renal transplant recipients from the same multi-organ donor. Both recipients suffered from severe hemorrhages from renal graft anastomosis and renal artery pseudoaneurysm due to Candida albicans arteritis (CAA). The culture of the preservation fluid revealed growth of Escherichia coli, but neither preservation fluid nor multiple routine blood cultures performed before hemorrhagic complications revealed fungal growth (media non-selective for fungal growth were applied). The first recipient suffered from sudden severe hemorrhage in the area of graft anastomosis on day 10 post surgery (without any preceding clinical or radiological symptoms). This led to urgent surgery and graftectomy, which was complicated by cardio-respiratory arrest with resuscitation in the operating room; despite resuscitation, irreversible brain damage, and subsequent death occurred in the intensive care unit (ICU) 2 weeks later (on day 24 after transplantation). The second patient underwent urgent vascular surgery on day 22 (after transplantation), because of hemorrhage from a pseudoaneurysm of the graft artery. She required repeated vascular operations, extended antimicrobial and antifungal therapy, and ICU monitoring and, despite these interventions, she died on day 80 after transplantation as a result of Pseudomonas aeruginosa sepsis. Arteritis of the renal artery in both patients was caused by C. albicans. This was confirmed by histopathology: infiltration of renal artery with budding yeast forming pseudohyphae (Case 1), and the presence of C. albicans in the culture of the renal artery and surrounding tissue (Case 2). We conclude that organ preservation solution should be cultured with use of media selective for fungal growth. As soon as the positive culture is detected, appropriate measures protecting patients against CAA should be undertaken.

Presentation and management of mycotic pseudoaneurysm after kidney transplantation

Pseudoaneurysms (PAs) developing at the site of vascular anastomosis after organ transplantation are a rare but serious complication. We report a series of 3 cases of PA observed in a single center over a period of 18 years. The mode of presentation was acute bleeding in 2 cases. In the third patient, who underwent combined kidney and pancreas transplantation, the PA on the renal graft was discovered by chance. Graft removal associated with iliac artery ligation and extra-anatomic femoro-femoral bypass represents the standard treatment. However, interposition of a venous homograft may allow preservation of inferior limb perfusion and possibly graft salvage.

Selecting suitable solid organ transplant donors: Reducing the risk of donor-transmitted infections

Selection of the appropriate donor is essential to a successful allograft recipient outcome for solid organ transplantation. Multiple infectious diseases have been transmitted from the donor to the recipient via transplantation. Donor-transmitted infections cause increased morbidity and mortality to the recipient. In recent years, a series of high-profile transmissions of infections have occurred in organ recipients prompting increased attention on the process of improving the selection of an appropriate donor that balances the shortage of needed allografts with an approach that mitigates the risk of donor-transmitted infection to the recipient. Important advances focused on improving donor screening diagnostics, using previously excluded high-risk donors, and individualizing the selection of allografts to recipients based on their prior infection history are serving to increase the donor pool and improve outcomes after transplant. This article serves to review the relevant literature surrounding this topic and to provide a suggested approach to the selection of an appropriate solid organ transplant donor.

Candida species contamination of preservation fluid-outcome of renal transplantation in 6 patients

BACKGROUND

Fungal infections are a rare but important cause of morbidity and mortality in kidney transplantation. Fungal contamination of the kidney preservation fluid may, sometimes, be the cause of these infections. However, the clinical consequences of fungal contamination of this fluid are not completely understood and literature on this topic is controversial. The purpose of this study was to determine the incidence of preservation fluid contamination by fungi and its clinical consequences.

METHODS

From June 2010 to September 2011, a prospective cohort analysis was conducted at our center, enrolling all patients who received a renal allograft and whose perfusion fluid was analyzed for microbiology sterility. Patients with perfusion fluids positive for fungi were further studied: the patients' status was assessed during regular visits and data were recorded, including clinical characteristics, infections, graft function, immunosuppressive regimen and outcomes.

RESULTS

Microbiologic, cultures of 70 kidney perfusion fluids using specific mycologic media, obtained from 74 cadaveric renal transplants (4 fluids were unsuitable for analysis), were evaluated. Six samples were positive for yeasts (8.6%), with 4 isolates of Candida albicans and 2 isolates of Candida glabrata. Four patients had no evidence of fungal infection during the follow-up period (median 321 days); conversely, 2 patients developed severe mycotic vascular complications leading to transplantectomy.

CONCLUSIONS

Perfusion fluid contamination by fungi is an elusive situation that can lead either to an unremarkable clinical course or to graft loss life-threatening situations. Routine culture of kidney perfusion fluid is critical for prompt diagnosis and early implementation of appropriate treatment.

"True" mycotic aneurysm of the anastomotic site of the renal allograft artery

The incidence of vascular complications after renal transplant as reported varies from 3.5% to 14%. Pseudoaneurysm formation at the site of the anastomosis is a rare complication, and only a few cases have been reported. There also were only a few reports of "true" mycotic aneurysms of the renal allograft artery. We present 2 patients with true mycotic aneurysmal formation of the renal allograft artery after a renal transplant. Both patients presented with fever and increasing serum creatinine levels. Cultures from aneurysm tissue samples have grown Aspergillus flavus. Both patients were subjected to an allograft nephrectomy, and amphotericin was given.

Successful repair of post-transplant mycotic aneurysm of iliac artery with renal graft preservation: a case report

OBJECTIVE

To describe the successful repair of a post-transplant iliac artery aneurysm with renal graft preservation.

METHODS

An aneurysm was detected in an asymptomatic 47-year-old male recipient on routine Doppler ultrasonography that involved the right external iliac artery and the distal portion of the renal artery. Aneurysm resection was performed immediately after diagnosis 3 months after transplantation. A polytetrafluorethylene tube graft was used for reconstruction of the right external iliac artery. Reconstruction of the renal artery required interposition of a vena saphena graft between the proximal portion of the renal artery and the polytetrafluorethylene tube.

RESULTS

The total warm ischemia time used for aneurysm repair and renal transplant revascularization was 90 minutes. The postoperative Doppler ultrasound scan showed homogeneous graft perfusion. Pathologic and microbiologic examination of the resected aneurysm revealed Candida albicans arteritis. The center in which the contralateral donor kidney was transplanted had previously reported Candida albicans contamination of the preservation solution. The recipient of the contralateral kidney lost his graft owing to bleeding complications. Information on this incident was acquired by our center only after aneurysm repair. Postoperatively, our recipient was given systemic antifungal therapy. At 6 months, the serum creatinine level was 1.7 mg/dL.

CONCLUSION

Although a high-risk procedure, repair of a mycotic aneurysm with renal graft preservation is feasible. Routine microbiologic screening of the preservation solution might help to detect and treat donor-transmitted infections in renal transplant recipients.

Donor-derived fungal infections in organ transplant recipients: guidelines of the American Society of Transplantation, infectious diseases community of practice

Donor-derived fungal infections can be associated with serious complications in transplant recipients. Most cases of donor-derived candidiasis have occurred in kidney transplant recipients in whom contaminated preservation fluid is a commonly proposed source. Donors with cryptococcal disease, including those with unrecognized cryptococcal meningoencephalitis may transmit the infection with the allograft. Active histoplasmosis or undiagnosed and presumably asymptomatic infection in the donor that had not resolved by the time of death can result in donor-derived histoplasmosis in the recipient. Potential donors from an endemic area with either active or occult infection can also transmit coccidioidomycosis. Rare instances of aspergillosis and other mycoses, including agents of mucormycosis may also be transmitted from infected donors. Appropriate diagnostic evaluation and prompt initiation of appropriate antifungal therapy are warranted if donor-derived fungal infections are a consideration. This document discusses the characteristics, evaluation and approach to the management of donor-derived fungal infections in organ transplant recipients.

Invasive Candida infections in solid organ transplant recipient children

Solid organ transplantation (SOT) is now an accepted therapy for many end-stage organ disorders and fungal infections are the principal cause of infection-related mortality in SOT recipients. Among invasive fungal infections, Candida species are the most common pathogens identified, associated with high mortality rates. The epidemiology and clinical manifestations of Candida infections vary with the type of organ transplantation. This article reviews invasive Candida infections in pediatric SOT recipients.

Mycotic pseudoaneurysm following a kidney transplant: a case report and review of the literature

Vascular complications represent a significant cause of morbidity and mortality following a kidney transplant. Pseudoaneurysms are rare, occurring in approximately 1% of cases. We present a 15-yr-old patient who received a kidney transplant in the right iliac fossa. Thirty-six days following the transplant, the patient was admitted to the hospital because of a marked increase in serum creatinine levels, arterial hypertension, scrotal edema, and lower right limb pain. The patient did not present fever or raised inflammatory markers. A pseudoaneurysm was diagnosed by means of a Doppler echography and a CT. By a selective arteriography of the right iliac artery, we placed a 8 x 5 cm stent to isolate the pseudoaneurysm, due to the high risk of an extensive defect occurring in the arterial wall. Forty-eight h later the patient underwent transplant nephrectomy. Seven days following surgery, the patient experienced febrile syndrome and therefore another CT was carried out which showed a large abscess around the stent. So we decided to perform another intervention in order to drain this abscess. Due to the extensive loss of the arterial wall where the prosthesis was largely exposed, we ligated the common iliac and external iliac arteries, removed the prosthesis and performed a femoro-femoral bypass with the usual subcutaneous positioning of the prosthesis (separate from surgical site). The stent and mural thrombus were sent for culture analysis and Candida albicans was observed. The diagnosis of a pseudoaneurysm in these types of patients continues to be considered as a surgical emergency by the majority of authors. Transplantectomy is the most frequently used treatment technique. Positioning a stent prior to transplantectomy avoids ligature of the iliac artery in the majority of cases.

Anti-infectious activity of tryptophan metabolites in the L-tryptophan-L-kynurenine pathway

To study the anti-infectious effect of a vascular allograft, the antimicrobial activity of tryptophan metabolites mediated by indoleamine 2,3-dioxygenase was determined. The growth of methicillin-resistant Staphylococcus aureus (MRSA) over 10 h in extracts from post-transplantation vascular allograft was significantly slower than that of extracts from non-transplantation vascular allograft regardless of the presence of tryptophan (p<0.05). When the antimicrobial activity of the tryptophan metabolites in the L-tryptophan-L-kynurenine pathway was examined, 3-hydroxy-DL-kynurenine and alpha-picolinic acid had strong antibacterial activity against MRSA, S. epidermidis, Escherichia coli, and multidrug-resistant Pseudomonas aeruginosa, although antimicrobial activities of anthranilic acid, 3-hydroxyanthranilic acid, and quinolinic acid against them were low. The results showed that, of the tested tryptophan metabolites, 3-hydroxy-DL-kynurenine and alpha-picolinic acid contributed to the anti-infectious effects of the allograft by inhibiting of the growth of microorganisms.

Evidence that graft-site candidiasis after kidney transplantation is acquired during organ recovery: a multicenter study in France

BACKGROUND

Infections of renal grafts with Candida species can induce life-threatening complications in the recipient.

METHODS

A 9-year retrospective study involving all of the transplant centers in France was designed to determine the incidence, origin, characteristics, and outcome of graft-site candidiasis that occurred after kidney transplantation. Yeasts cultured from preservation or drainage solutions and graft specimens were recorded.

RESULTS

Among 18,617 kidney grafts, 18 recipients corresponding to 12 donors developed culture-confirmed graft-site candidiasis (incidence, 1 case per 1000 grafts) a median of 25 days after the graft procedure. Clinical presentations included 14 cases of renal arteritis (13 were complicated by aneurysm), 1 urinoma, 2 graft site abscesses, and 1 surgical site infection. Candida albicans was involved in 13 cases. A unique C. albicans genotype or a single rare Candida species was involved in each episode. Together with the clinical history, these findings demonstrate that organ contamination followed by transmission to the recipient occurred during recovery. Therapeutic management varied from simple monitoring in 1 case to a combination of surgery (nephrectomy in 9 cases and arterial bypass in 9 cases) and antifungal therapy (14 cases). Overall, 3 of 18 kidney transplant recipients died, and 9 had their graft surgically removed.

CONCLUSION

Graft-transmitted candidiasis that ends most often in fungal arteritis is associated with high morbidity and mortality after kidney transplantation and is related to organ contamination during recovery in the donor.

[Mycotic aneurysm and renal transplant. A case report]

The arterial aneurysm secondary to Candida is a rare but frightening complication of renal transplant. We report the case of a 58-year-old patient who developed an arterial aneurysm secondary to a Candida infection in 3 weeks of a third renal transplant. Candida albicans was isolated from the preservation solution. The treatment consisted of a transplant nephrectomy, aneurysm excision and an iliac bypass with cryopreserved iliac homograft. All of bacteriologic culture was positive for Candida. The positive bacteriologic culture for Candida in preservation solution requires antifongic treatment. In case of arterial aneurysm, a surgical treatment is necessary but majority of kidney transplant had to be removed.

Outcome of renal transplantation in eight patients with Candida sp. contamination of preservation fluid

The complications of kidney graft preservation fluid infected by Candida sp. may range in severity from trivial infections to life-threatening complications, including graft arteritis and anastomotic rupture. Mandatory nephrectomy has recently been proposed as a means of preventing arterial wall rupture in such cases. We describe the clinical features and outcome of renal transplantation from a cadaveric donor in eight recipients with preservation fluid testing positive for Candida sp. Six patients were treated with antifungal drugs. After 1-2 years of follow-up, including regular imaging, none of the patients had developed arterial aneurysm, and all had a functional allograft and were alive. The contamination of renal graft preservation fluid with Candida sp. may be uneventful and should not systematically lead to removal of the graft. Until other risk factors for vascular complications have been determined, early antifungal treatment and repeated radiological monitoring are advisable for the prevention and/or early detection of such complications.

Long-term outcomes and late complications of laparoscopic nephrectomy with renal autotransplantation

PURPOSE

We report long-term outcomes and late complications after laparoscopic nephrectomy with autotransplantation.

MATERIALS AND METHODS

We retrospectively reviewed clinical data on all patients who underwent laparoscopic nephrectomy with autotransplantation between July 2000 and March 2007. Late complications, ie greater than 6 months, that required surgical intervention were analyzed. Clinical outcomes in patients with primary ureteral stricture disease and oncological outcomes in patients with renal tumors were examined.

RESULTS

Indications for autotransplantation included complex ureteral stricture disease in 15 patients and renal malignancy in 4. Median age at surgery was 48 years (range 25 to 68). Median followup was 29 months. Of the 17 patients with greater than 6 months of followup late complications requiring surgical intervention occurred in 4. Transplant nephrectomy was required in 2 patients in the stricture group. Indications for nephrectomy were nonfunction complicated by pseudoaneurysm in 1 case and chronic loin pain in 1. Another patient had recurrent nephrolithiasis requiring percutaneous nephrolithotomy and in 1 a pseudoaneurysm was managed successfully by endovascular techniques. Two patients in the tumor group had disease progression, which was managed medically.

CONCLUSIONS

Given the complexity and severity of disease that necessitates renal autotransplantation, it is not surprising that additional treatments are required. Patients with primary stricture disease may be at increased risk for vascular aneurysm due to infection and/or inflammation. Tumor progression is possible after ex vivo tumor excision and autotransplantation, especially in patients requiring heroic measures to avoid or delay dialysis. Thus, careful patient selection and vigilant followup are mandatory.