Candida in solid organ transplant recipients

Natural history and prognostic factors of candidemia in kidney transplant recipients: A retrospective, multinational study

BACKGROUND

The natural history of candidemia in kidney transplant recipients (KTR) remains poorly understood. This study aimed to evaluate mortality, prognostic factors and overall graft loss after candidemia in KTRs.

METHODS

This is a retrospective multicentre study enrolling all KTRs ≥15 years old with candidemia diagnosed at hospitals in Brazil, Spain and Italy from 2010 to 2020. Primary endpoints were mortality rates at 14 and 30 days. Secondary endpoints were prognostic factors of 14-day mortality and overall graft loss.

RESULTS

We enrolled 93 KTRs of which 75 were from Brazil. The mean time interval from transplantation to the onset of candidemia was 45.2 ± 61.5 months. 42% of all patients were on haemodialysis, 31.3% had an episode of sepsis and 39% underwent surgery within 30 days before fungemia. European patients were more likely to receive echinocandin (32 vs. 72%, p < .001). 22.7% of Brazilian patients did not receive any antifungal before death. All-cause mortality at 14 days was higher in Brazil (41.3 vs. 11.1%, p = .016). Candida colonisation (OR 6.91 [95% CI: 1.08-44.3], p = .042) and hypotension (OR 4.87 [95% CI: 1.62-14.66], p = .005) were associated with 14-day mortality. Echinocandin treatment had a protective effect (OR 0.19 [95% CI: 0.05-0.73], p = .015). Graft loss at 90 days occurred in 48% of patients (70.7 in Brazil vs. 22.2% in Europe, p < .01).

CONCLUSIONS

Candidemia in KTR is usually documented late after engraftment in patients requiring HD, surgical procedures and dysbiosis secondary to antibiotic use. Mortality was higher in Brazil. Echinocandin therapy was associated with improved survival.

Infections after organ transplantation and immune response

Organ transplantation has provided another chance of survival for end-stage organ failure patients. Yet, transplant rejection is still a main challenging factor. Immunosuppressive drugs have been used to avoid rejection and suppress the immune response against allografts. Thus, immunosuppressants increase the risk of infection in immunocompromised organ transplant recipients. The infection risk reflects the relationship between the nature and severity of immunosuppression and infectious diseases. Furthermore, immunosuppressants show an immunological impact on the genetics of innate and adaptive immune responses. This effect usually reactivates the post-transplant infection in the donor and recipient tissues since T-cell activation has a substantial role in allograft rejection. Meanwhile, different infections have been found to activate the T-cells into CD₄⁺ helper T-cell subset and CD₈⁺ cytotoxic T-lymphocyte that affect the infection and the allograft. Therefore, the best management and preventive strategies of immunosuppression, antimicrobial prophylaxis, and intensive medical care are required for successful organ transplantation. This review addresses the activation of immune responses against different infections in immunocompromised individuals after organ transplantation.

Invasive Fungal Breakthrough Infections under Targeted Echinocandin Prophylaxis in High-Risk Liver Transplant Recipients

Invasive fungal infections (IFIs) are frequent and outcome-relevant complications in the early postoperative period after orthotopic liver transplantation (OLT). Recent guidelines recommend targeted antimycotic prophylaxis (TAP) for high-risk liver transplant recipients (HR-LTRs). However, the choice of antimycotic agent is still a subject of discussion. Echinocandins are increasingly being used due to their advantageous safety profile and the increasing number of non-albicans Candida infections. However, the evidence justifying their use remains rather sparse. Recently published data on breakthrough IFI (b-IFI) raise concerns about echinocandin efficacy, especially in the case of intra-abdominal candidiasis (IAC), which is the most common infection site after OLT. In this retrospective study, we analyzed 100 adult HR-LTRs undergoing first-time OLT and receiving echinocandin prophylaxis between 2017 and 2020 in a tertiary university hospital. We found a breakthrough incidence of 16%, having a significant impact on postoperative complications, graft survival, and mortality. The reasons for this may be multifactorial. Among the pathogen-related factors, we identified the breakthrough of Candida parapsilosis in 11% of patients and one case of persistent IFI due to the development of a secondary echinocandin resistance of an IAC caused by Candida glabrata. Consequently, the efficacy of echinocandin prophylaxis in liver transplantation should be questioned. Further studies are necessary to clarify the matter of breakthrough infections under echinocandin prophylaxis.

Incidence of Invasive Fungal Infections in Liver Transplant Recipients under Targeted Echinocandin Prophylaxis

Invasive fungal infections (IFIs) are one of the most important infectious complications after liver transplantation, determining morbidity and mortality. Antimycotic prophylaxis may impede IFI, but a consensus on indication, agent, or duration is still missing. Therefore, this study aimed to investigate the incidence of IFIs under targeted echinocandin antimycotic prophylaxis in adult high-risk liver transplant recipients. We retrospectively reviewed all patients undergoing a deceased donor liver transplantation at the Medical University of Innsbruck in the period from 2017 to 2020. Of 299 patients, 224 met the inclusion criteria. We defined patients as being at high risk for IFI if they had two or more prespecified risk factors and these patients received prophylaxis. In total, 85% (190/224) of the patients were correctly classified according to the developed algorithm, being able to predict an IFI with a sensitivity of 89%. Although 83% (90/109) so defined high-risk recipients received echinocandin prophylaxis, 21% (23/109) still developed an IFI. The multivariate analysis identified the age of the recipient (hazard ratio-HR = 0.97, p = 0.027), split liver transplantation (HR = 5.18, p = 0.014), massive intraoperative blood transfusion (HR = 24.08, p = 0.004), donor-derived infection (HR = 9.70, p < 0.001), and relaparotomy (HR = 4.62, p = 0.003) as variables with increased hazard ratios for an IFI within 90 days. The fungal colonization at baseline, high-urgency transplantation, posttransplant dialysis, bile leak, and early transplantation showed significance only in a univariate model. Notably, 57% (12/21) of the invasive Candida infections were caused by a non-albicans species, entailing a markedly reduced one-year survival. The attributable 90-day mortality rate of an IFI after a liver transplant was 53% (9/17). None of the patients with invasive aspergillosis survived. Despite targeted echinocandin prophylaxis, there is still a notable risk for IFI. Consequently, the prophylactic use of echinocandins must be critically questioned regarding the high rate of breakthrough infections, the increased occurrence of fluconazole-resistant pathogens, and the higher mortality rate in non-albicans Candida species. Adherence to the internal prophylaxis algorithms is of immense importance, bearing in mind the high IFI rates in case algorithms are not followed.

Fungal Tracheobronchitis in Lung Transplant Recipients: Incidence and Utility of Diagnostic Markers

Fungal tracheobronchitis caused by Aspergillus and Candida spp. is a recognized complication after lung transplantation, but knowledge of the incidence of Candida tracheobronchitis is lacking. The diagnosis relies on fungal cultures in bronchoalveolar lavage fluid (BALF), but cultures have low specificity. We aimed to evaluate the one-year incidence of fungal tracheobronchitis after lung transplantation and to assess the utility of diagnostic markers in serum and BALF to discriminate fungal tracheobronchitis from colonization. Ninety-seven consecutively included adult lung-transplant recipients were prospectively followed. BALF and serum samples were collected at 1, 3 and 12 months after transplantation and analyzed for betaglucan (serum and BALF), neutrophils (BALF) and galactomannan (BALF). Fungal tracheobronchitis was defined according to consensus criteria, modified to include Candida as a mycologic criterion. The cumulative one-year incidence of Candida and Aspergillus tracheobronchitis was 23% and 16%, respectively. Neutrophils of >75% of total leukocytes in BALF had 92% specificity for Candida tracheobronchitis. The area under the ROC curves for betaglucan and galactomannan in BALF to discriminate Aspergillus tracheobronchitis from colonization or no fungal infection were high (0.86 (p < 0.0001) and 0.93 (p < 0.0001), respectively). To conclude, the one-year incidence of fungal tracheobronchitis after lung transplantation was high and dominated by Candida spp. Diagnostic markers in BALF could be useful to discriminate fungal colonization from tracheobronchitis.

Emerging of Fatal Colitis with Multidrug-Resistant Candida glabrata after Small Bowel Transplantation

Background

Small bowel transplantation is a potential option for patients with intestinal-failure, and the incidences of infections caused by Candida species that are more resistant to antifungal drugs are increasing in these patients. In this manuscript, we reported a case of fatal colitis after small bowel transplantation induces by multidrug-resistant (MDR) Candida glabrata. Case Presentation. A 52-year-old man has undergone an extensive small bowel resection with the length of the remaining bowel which was less than 40 cm who became a candidate for transplantation. Four months after transplantation, the patient experienced severe bloody diarrhea with abdominal distension. Ileoscopy and colonoscopy did not show neither pathological change and rejection nor cytomegalovirus (CMV) infection posttransplantation. Abdomen computed tomography showed diffuse moderate small bowel wall thickening. After detection of budding yeast in the stool samples, stool culture was positive for Candida, DNA was extracted, and ITS1-5.8s-ITS2 region of the fungal agent was amplified. Sequencing analysis of PCR and antifungal susceptibility testing revealed that this isolate was multidrug-resistant C. glabrata. Besides, there was no evidence for other pathogens known to cause infection in various laboratory tests. Immediate antifungal treatments with caspofungin remained unsuccessful, and on the eighteenth day of admission, the patient expires with septic shock.

Conclusion

These findings highlight the challenging management of candidiasis in patients with small bowel transplantation. Infectious diseases due to MDR organisms have emerged as a vital clinical problem in this patient population.

Perioperative anidulafungin combined with triazole prophylaxis for the prevention of early invasive candidiasis in lung transplant recipients

BACKGROUND

Invasive candidiasis (IC) is a substantial cause of morbidity and mortality among lung transplant recipients (LTRs). Postoperative factors include prolonged hospital stay, central lines, delayed chest closure, and dehiscence increase IC risk. Correspondingly, current guidelines propose targeted IC coverage early posttransplant with fluconazole or an echinocandin.

METHODS

This retrospective analysis was performed on LTRs from January 2016 to January 2020 and evaluated effectiveness of a recent protocol utilizing perioperative anidulafungin for early IC prevention in addition to long-term triazole antifungal prophylaxis. Prior to this protocol, patients were primarily established on itraconazole prophylaxis alone. The primary endpoint was proven or probable IC within 90 days after transplant. Multivariable logistic regression modeling was used to assess risk factors for invasive fungal infection (IFI).

RESULTS

Among 144 LTRs, there was a numerically lower incidence of IC in the protocol group, although not statistically significant (6% vs. 13%, p = 0.16). Incidence of proven or probable IFI was 7.5% in the protocol cohort and 19.5% in the pre-protocol cohort (p = 0.038). In multivariable analysis, when controlling for lung allocation score (OR 1.04, 95% CI 1.01-1.08), donor perioperative culture with fungal growth (OR 2.92, 95% CI 1.02-8.92), and dehiscence (OR 3.54, 95% CI 1.14-10.85), protocol cohort was not significantly associated with IFI (OR 0.41, 95% CI 0.12-1.23).

CONCLUSIONS

To our knowledge, this is the first study investigating combination triazole/echinocandin use in the early post-lung transplant period. These findings demonstrate that in-hospital anidulafungin offers unclear benefit for early IC prevention when used in combination with triazole prophylaxis.

Early postoperative complications in lung transplant recipients

Lung transplantation has become an established therapy for end-stage lung diseases. Early postoperative complications can impact immediate, mid-term, and long-term outcomes. Appropriate management, prevention, and early detection of these early postoperative complications can improve the overall transplant course. In this review, we highlight the incidence, detection, and management of these early postoperative complications in lung transplant recipients.

Adherence to the guidelines for surgical antimicrobial prophylaxis in a Saudi tertiary care hospital

Objective

The study evaluated the adherence to the guidelines for surgical antimicrobial prophylaxis in a Saudi tertiary care hospital.

Methods

The medical records of 707 patients from the surgical units over a selected 3-month period were selected. The data were reviewed and statistically analysed.

Results

Of the 707 respondents, 51.2% were women and most were older than 50 years. The most common surgical procedures involved orthopaedics (28.3%), followed by vascular surgery (15.1%). One hundred and thirty-eight (19.5%) patients received antibiotics according to the guidelines for surgical prophylaxis. More than half of the patients (399/56.4%) received antibiotics for more than 24 h and 129 (18.2%) received antibiotics for less than 24 h. Single dose antibiotic therapy was used in 179 (25.3%) patients. Two hundred and ninety-seven (42%) patients underwent clean surgery, 284 (40%) clean-contaminated and 128 (18%) contaminated surgery. A significant difference was evident between the antibiotics administered according to the recommended guidelines and the duration of antibiotic therapy (p = 0.001), duration (p = 0.001) and the type of surgical procedure (p = 0.00).

Conclusion

The findings of this study suggest that healthcare professionals do not strictly adhere to the guidelines for surgical antibiotic prophylaxis. Physicians are therefore encouraged to follow the recommendations appropriately and to regularly implement surgical antimicrobial prophylaxis for patient safety.

Regulatory mechanisms controlling morphology and pathogenesis in Candida albicans

Candida albicans, a major human fungal pathogen, can cause a wide variety of both mucosal and systemic infections, particularly in immunocompromised individuals. Multiple lines of evidence suggest a strong association between virulence and the ability of C. albicans to undergo a reversible morphological transition from yeast to filamentous cells in response to host environmental cues. Most previous studies on mechanisms important for controlling the C. albicans morphological transition have focused on signaling pathways and sequence-specific transcription factors. However, in recent years a variety of novel mechanisms have been reported, including those involving global transcriptional regulation and translational control. A large-scale functional genomics screen has also revealed new roles in filamentation for certain key biosynthesis pathways. This review article will highlight several of these exciting recent discoveries and discuss how they are relevant to the development of novel antifungal strategies. Ultimately, components of mechanisms that control C. albicans morphogenesis and pathogenicity could potentially serve as viable antifungal targets.

Risk index for early infections following living donor liver transplantation

INTRODUCTION

Post-operative infections in patients undergoing living donor liver transplantation (LDLT) are a major cause of morbidity and mortality. This study aims to develop a practical and efficient prognostic index for early identification and possible prediction of post-transplant infections using risk factors identified by multivariate analysis.

MATERIAL AND METHODS

One hundred patients with post-hepatitic cirrhosis, HCV positive, genotype 4, Child B/C or MELD score 13-25 undergoing LDLT were included. All potential predictors of infection were analyzed by backward logistic regression. Cut-off values were obtained from ROC curve analysis. Significant predictors were combined into a risk index, which was further tested and compared by ROC curve analysis.

RESULTS

Post-operative infection was associated with a significantly higher mortality (50.7% vs. 33.3%). Total leucocyte count, total bilirubin, early biliary complications, fever and C-reactive protein were found to be independent predictors of early infectious complications after LDLT. The risk index predicted infection with the highest sensitivity and specificity as compared with each predictor on its own (AUC = 0.91, 95% CI: 0.830-0.955, p < 0.0001).

CONCLUSIONS

The use of a combined risk index for early diagnosis of post-operative infections can efficiently identify high risk patients.

Dermatological Disorders following Liver Transplantation: An Update

Patients undergoing liver transplantation (LT) are at a high risk of dermatological complications compared to the general population as a result of long-term use of immunosuppressant. However, the risk is not as high as other solid organ transplantations (SOT), particularly for skin cancer. The liver is considered as an immune privileged organ since it has a low prevalence of humoral rejection in contrast to other SOT, and thus, LT requires a minimal amount of immunosuppressants compared to other SOT recipients. However, because of the large volume of the liver, patients with LT have higher donor lymphocytes that sometimes may trigger graft-versus-host-disease, yet it is rare. On the other hand, the vast majority of the nonspecific dermatological lesions linked with cirrhosis improve after removal of diseased liver or due to the immunosuppressant used after LT. Nevertheless, dermatological infections related to bacteria, viruses, and fungus after LT are not uncommon. Additionally, the incidence of IgE-mediated food allergies develops in 12.2% of LT patients and may present as life-threatening conditions such as urticaria and/or angioedema and hypersensitivity. Moreover, skin malignancies after LT are a matter of concern. Thus, posttransplant dermatological care should be provided to all LT patients for any suspicious dermatological lesions. Our goal is to give an outline of the dermatological manifestation associated with LT for the clinicians by collecting the published data from all archived case reports.

Use of echinocandin prophylaxis in solid organ transplantation

Invasive fungal infections (IFIs) are a major threat to patients undergoing solid organ transplantation (SOT). Owing to improvements in surgical techniques, immunosuppression therapy and antifungal prophylaxis, the incidence of IFIs has been decreasing in recent years. However, IFI-associated morbidity and mortality remain significant. Invasive candidiasis (IC) and aspergillosis (IA) are the main IFIs after SOT. Risk factors for IC and IA continue to evolve, and thus strategies for their prevention should be constantly updated and targeted to both individual patient risk factors and local epidemiology. In this review, we discuss the current epidemiology and risk factors for IFIs in SOT recipients in the context of actual approaches to antifungal prophylaxis, including experience with the use of echinocandins, after SOT.

Infection in Kidney Transplant Recipients

In organ transplant recipients, impaired inflammatory responses suppress the clinical and radiologic findings of infection. The possible etiologies of infection are diverse, ranging from common bacterial and viral pathogens that affect the entire community to opportunistic pathogens that cause invasive disease only in immunocompromised hosts. Antimicrobial therapies required to treat established infection are often complex, with accompanying risks for drug toxicities and drug interactions with the immunosuppressive agents used to maintain graft function. Rapid and specific diagnosis is essential for successful therapy. The risk of serious infections in the organ transplant patient is largely determined by the interaction between two factors: the patient’s epidemiologic exposures and the patient’s net state of immunosuppression. The epidemiology of infection includes environmental exposures and nosocomial infections, organisms derived from donor tissues, and latent infections from the recipient activated with immunosuppression. The net state of immune suppression is a conceptual framework that measures those factors contributing to risk for infection: the dose, duration, and temporal sequence of immunosuppressive drugs; the presence of foreign bodies or injuries to mucocutaneous barriers; neutropenia; metabolic abnormalities including diabetes; devitalized tissues, hematomas, or effusions postsurgery; and infection with immunomodulating viruses. Multiple factors are present in each host. A timeline exists to aid in the development of a differential diagnosis for infection. The timeline for each patient is altered by changes in prophylaxis and immunosuppressive drugs. For common infections, new microbiologic assays, often nucleic acid based, are useful in the diagnosis and management of opportunistic infections.

Synergistic and antagonistic effects of immunomodulatory drugs on the action of antifungals against Candida glabrata and Saccharomyces cerevisiae

Candidemia and other forms of invasive fungal infections caused by Candida glabrata and to a lesser extent Saccharomyces cerevisiae are a serious health problem, especially if their steadily rising resistance to the limited range of antifungal drugs is taken into consideration. Various drug combinations are an attractive solution to the resistance problem, and some drug combinations are already common in the clinical environment due to the nature of diseases or therapies. We tested a few of the common antifungal-immunomodulatory drug combinations and evaluated their effect on selected strains of C. glabrata and S. cerevisiae. The combinations were performed using the checkerboard microdilution assay and interpreted using the Loewe additivity model and a model based on the Bliss independence criterion. A synergistic interaction was confirmed between calcineurin inhibitors (Fk506 and cyclosporine A) and antifungals (fluconazole, itraconazole, and amphotericin B). A new antagonistic interaction between mycophenolic acid (MPA) and azole antifungals was discovered in non-resistant strains. A possible mechanism that explains this is induction of the Cdr1 efflux pump by MPA in C. glabrata ATCC 2001. The Pdr1 regulatory cascade plays a role in overall resistance to fluconazole, but it is not essential for the antagonistic interaction. This was confirmed by the Cgpdr1Δ mutant still displaying the antagonistic interaction between the drugs, although at lower concentrations of fluconazole. This antagonism calls into question the use of simultaneous therapy with MPA and azoles in the clinical environment.

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.

Infection in Organ Transplantation

The prevention, diagnosis, and management of infectious disease in transplantation are major contributors to improved outcomes in organ transplantation. The risk of serious infections in organ recipients is determined by interactions between the patient's epidemiological exposures and net state of immune suppression. In organ recipients, there is a significant incidence of drug toxicity and a propensity for drug interactions with immunosuppressive agents used to maintain graft function. Thus, every effort must be made to establish specific microbiologic diagnoses to optimize therapy. A timeline can be created to develop a differential diagnosis of infection in transplantation based on common patterns of infectious exposures, immunosuppressive management, and antimicrobial prophylaxis. Application of quantitative molecular microbial assays and advanced antimicrobial therapies have advanced care. Pathogen-specific immunity, genetic polymorphisms in immune responses, and dynamic interactions between the microbiome and the risk of infection are beginning to be explored. The role of infection in the stimulation of alloimmune responses awaits further definition. Major hurdles include the shifting worldwide epidemiology of infections, increasing antimicrobial resistance, suboptimal assays for the microbiologic screening of organ donors, and virus-associated malignancies. Transplant infectious disease remains a key to the clinical and scientific investigation of organ transplantation.

Metabolic adaptation via regulated enzyme degradation in the pathogenic yeast Candida albicans

The virulence of Candida albicans is dependent upon fitness attributes as well as virulence factors. These attributes include robust stress responses and metabolic flexibility. The assimilation of carbon sources is important for growth and essential for the establishment of infections by C. albicans. Previous studies showed that the C. albicans ICL1 genes, which encode the glyoxylate cycle enzymes isocitratelyase are required for growth on non-fermentable carbon sources such as lactate and oleic acid and were repressed by 2% glucose. In contrast to S. cerevsiae, the enzyme CaIcl1 was not destabilised by glucose, resulting with its metabolite remaining at high levels. Further glucose addition has caused CaIcl1 to lose its signal and mechanisms that trigger destabilization in response to glucose. Another purpose of this study was to test the stability of the Icl1 enzyme in response to the dietary sugars, fructose, and galactose. In the present study, the ICL1 mRNAs expression was quantified using Quantitative Real Time PCR, whereby the stability of protein was measured and quantified using Western blot and phosphoimager, and the replacing and cloning of ICL1 ORF by gene recombination and ubiquitin binding was conducted via co-immuno-precipitation. Following an analogous experimental approach, the analysis was repeated using S. cerevisiaeas a control. Both galactose and fructose were found to trigger the degradation of the ICL1 transcript in C. albicans. The Icl1 enzyme was stable following galactose addition but was degraded in response to fructose. C. albicans Icl1 (CaIcl1) was also subjected to fructose-accelerated degradation when expressed in S. cerevisiae, indicating that, although it lacks a ubiquitination site, CaIcl1 is sensitive to fructose-accelerated protein degradation. The addition of an ubiquitination site to CaIcl1 resulted in this enzyme becoming sensitive to galactose-accelerated degradation and increases its rate of degradation in the presence of fructose. It can be concluded that ubiquitin-independent pathways of fructose-accelerated enzyme degradation exist in C. albicans.

Infectious agents after liver transplant: etiology, timeline and patients' cell-mediated immunity responses

Infections continue to be one of the leading causes of morbidity and mortality in liver transplant recipients. We retrospectively reviewed the symptomatic infectious episodes that occurred during the first year post-transplant to determine time of onset, causative pathogens and cell-mediated immunity response patterns. Ninety-eight of the 202 (48.5%) recipients enrolled developed at least one infectious episode. The total number of infectious episodes was 135: 77 (57.1%) bacterial, 45 (33.3%) viral and 13 (9.6%) fungal. The most frequently isolated bacteria were Escherichia coli (21 isolates) and Klebsiella pneumoniae (19 isolates). Overall, extended-spectrum beta lactamase-producing and methicillin-resistant organisms were responsible for 29 (29/77; 37.7%) infectious episodes. Members of the herpes virus group, in particular cytomegalovirus (34/45 viral infections, 75.5%), were detected. Candida species (9 isolates) followed by Aspergillus species (4 isolates) were isolated. The majority of infections (63%) occurred during the early post-transplant phase (<1 month), whereas only 8/135 episodes (5.9%) were detected after the sixth month (late phase). Significantly lower median ImmuKnow^® intracellular ATP values in patients who developed bacterial and fungal infections compared to infection-free patients were observed (P < 0.0001 and P = 0.0016, respectively), whereas patients who developed a viral infection had a median intracellular ATP level not statistically different compared to uninfected patients (P = 0.4). Our findings confirm that bacteria are responsible for the majority of symptomatic infections and occur more frequently during the first month post-transplant. The ImmuKnow^® measurements can be a useful tool for identifying patients at high risk of developing infection, particularly of fungal and bacterial etiology.

Effect of Prophylactic Antifungal Protocols on the Prognosis of Liver Transplantation: A Propensity Score Matching and Multistate Model Approach

Background. Whether routine antifungal prophylaxis decreases posttransplantation fungal infections in patients receiving orthotopic liver transplantation (OLT) remains unclear. This study aimed to determine the effectiveness of antifungal prophylaxis for patients receiving OLT. Patients and Methods. This is a retrospective analysis of a database at Chang Gung Memorial Hospital. We have been administering routine antibiotic and prophylactic antifungal regimens to recipients with high model for end-stage liver disease scores (>20) since 2009. After propensity score matching, 402 patients were enrolled. We conducted a multistate model to analyze the cumulative hazards, probability of fungal infections, and risk factors. Results. The cumulative hazards and transition probability of “transplantation to fungal infection” were lower in the prophylaxis group. The incidence rate of fungal infection after OLT decreased from 18.9% to 11.4% (p = 0.052); overall mortality improved from 40.8% to 23.4% (p < 0.001). In the “transplantation to fungal infection” transition, prophylaxis was significantly associated with reduced hazards for fungal infection (hazard ratio: 0.57, 95% confidence interval: 0.34–0.96, p = 0.033). Massive ascites, cadaver transplantation, and older age were significantly associated with higher risks for mortality. Conclusion. Prophylactic antifungal regimens in high-risk recipients might decrease the incidence of posttransplant fungal infections.

Antifungal prophylaxis with liposomal amphotericin B and caspofungin in high-risk patients after liver transplantation: impact on fungal infections and immune system

Antifungal prophylaxis may be required in high-risk patients undergoing liver transplantation and for that reason we aimed to verify its role and its related impact on the graft. From January 2006 throughout 2012, 250 liver transplants were evaluated and 54 patients identified as being at higher risk were randomly selected to undergo the following schedule: 28 patients received liposomal amphotericin B and 26 received caspofungin. We evaluated, throughout 12 months, renal and liver function tests, bacterial and fungal infection episodes, and intensive care unit (ICU) stay, as well as the Th1 and Th2 cytokine network. Differences were analyzed according to non-parametric tests (two-tailed p values). Neither of the groups showed episodes of invasive fungal infection during the 12 months follow-up; however, patients receiving prophylaxis with liposomal amphotericin B had reduced episodes of bacterial infections coupled with an improved immune system response compared with those receiving caspofungin. Finally, a reduced stay in the ICU was also observed. In conclusion, even if the results of liposomal amphotericin B and caspofungin prophylaxis strategies did not differ in terms of invasive fungal infection rate, patients receiving prophylaxis with liposomal amphotericin B had a reduced ICU stay and an improved Th2 status, as well as a reduced number of post-transplant bacterial infections. Further studies are required to better address and evaluate these findings.

[Invasive yeast diseases in solid organ transplant recipients]

Invasive yeast diseases are uncommon nowadays in solid organ transplant recipients. Invasive candidiasis (2%) usually presents during the first month after transplantation in patients with risk factors. Both common and transplant-specific risk factors have been identified, allowing very efficacious targeted prophylaxis strategies. The most common clinical presentations are fungaemia and local infections near the transplantation area. Cryptococcosis is usually a late infection. Its incidence remains stable and the specific risk factors have not been identified. When cryptococcosis is detected very early, transmission with the allograft should be considered. The most common clinical presentations include meningitis, pneumonia, and disseminated infection. Intracranial hypertension and immune reconstitution syndrome have to be considered. No therapeutic clinical trials have been conducted in solid organ transplant recipients, thus treatment recommendations are derived from data obtained from the general population. It is particularly important to consider the possibility of drug-drug interactions, mainly between azoles and calcineurin inhibitors. Both invasive candidiasis and cryptococcosis increase the mortality significantly in solid organ transplant recipients.

Emerging pan-resistance in Trichosporon species: a case report

Background

Trichosporon species are ubiquitously spread and known to be part of the normal human flora of the skin and gastrointestinal tract. Trichosporon spp. normally cause superficial infections. However, in the past decade Trichosporon spp. are emerging as opportunistic agents of invasive fungal infections, particularly in severely immunocompromised patients. Clinical isolates are usually sensitive to triazoles, but strains resistant to multiple triazoles have been reported.

Case presentation

We report a high-level pan-azole resistant Trichosporon dermatis isolate causing an invasive cholangitis in a patient after liver re-transplantation. This infection occurred despite of fluconazole and low dose amphotericin B prophylaxis, and treatment with combined liposomal amphotericin B and voriconazole failed.

Conclusion

This case and recent reports in literature show that not only bacteria are evolving towards pan-resistance, but also pathogenic yeasts. Prudent use of antifungals is important to withstand emerging antifungal resistance.

Caspofungin versus fluconazole as prophylaxis of invasive fungal infection in high-risk liver transplantation recipients: A propensity score analysis

Targeted prophylaxis has proven to be an efficient strategy in liver transplantation recipients (LTRs). The aim of this study was to compare the effectiveness and safety of caspofungin with that of fluconazole in high-risk (HR) LTRs. Caspofungin and fluconazole were compared in a multicenter, retrospective, cohort study in HR-LTRs in Spain. Outcomes were assessed at 180 days after transplantation. A propensity score approach was applied. During the study period (2005-2012), we analyzed 195 HR-LTRs from 9 hospitals. By type of prophylaxis, 97 patients received caspofungin and 98 received fluconazole. Of a total of 17 (8.7%) global invasive fungal infections (IFIs), breakthrough IFIs accounted for 11 (5.6%) and invasive aspergillosis (IA) accounted for 6 (3.1%). By univariate analysis, no differences were observed in the prevention of global IFIs. However, caspofungin was associated with a significant reduction in the rate of breakthrough IFIs (2.1% versus 9.2%, P = 0.04). In patients requiring dialysis (n = 62), caspofungin significantly reduced the frequency of breakthrough IFIs (P = 0.03). The propensity score analysis confirmed a significant reduction in the frequency of IA in patients receiving caspofungin (absolute risk reduction, 0.06; 95% confidence interval [CI], 0.001-0.11; P = 0.044). Linear regression analysis revealed a significant decrease in blood alanine aminotransferase levels and a significant increase in bilirubin levels after administration of caspofungin. Caspofungin and fluconazole have similar efficacy for the prevention of global IFIs in HR-LTRs in this observational, multicenter cohort study. However, caspofungin was associated with a significant reduction of breakthrough IFIs and, after adjusting for confounders, caspofungin was associated with a lower rate of IA. This benefit is probably more favorable in patients on dialysis. Caspofungin is safe in HR-LTRs, although bilirubin levels may be increased.

Fungal infections after liver transplantation: incidence and outcome

BACKGROUND

Fungal infections, although less frequent than bacterial infections, represent a severe comorbidity with an exponential increase in mortality rate in liver transplantation patients. The incidence of invasive fungal infections (IFIs) after solid organ transplantation ranges from 7% to 42%, with Candida spp. and Aspergillus spp. as the most common pathogens. Fungal infections in liver transplant recipients have been associated with poor outcome and mortality rates ranging from 65% to 90% for invasive aspergillosis and 30% to 50% for invasive candidiasis. The results largely depend on early diagnosis and early initiation of specific treatment for IFIs. Therefore, the diagnosis must be prompt, preferably based on microbiological data, both cultures and biomarkers, and/or based on clinical features and known risk factors.

MATERIALS AND METHODS

This study evaluated the incidence of fungal infections in patients after liver transplantation in our center between January 2003 and December 2012. The retrospective analysis of 215 consecutive liver transplantation patients was undertaken to estimate incidence, risk factors, and clinical courses of IFIs in the first 3 months after liver transplantation.

RESULTS

Candidemia and invasive candidiasis microbiologically proven were found in 26 patients (12%), whereas in 6 patients (2.8%) invasive fungal infections from other non-Candida fungi developed: Aspergillus (4 cases: 2 A fumigatus, 2 A terreus), Fusarium oxysporum (1 case), and Rhodotorula rubra (1 case). Two patients with Aspergillus and the patient with Fusarium died. The patient with Rhodotorula as well as 22 of the patients with candidemia (85%) survived. All of the episodes developed during the first 3 months posttransplantation. All cases have followed a previous polymicrobial bacterial infection (especially in the biliary tract) with large use of combined antibiotic therapies.

CONCLUSIONS

The rate of fungal infection was found to increase in parallel with the number of risk factors. Prophylactic strategies can decrease the risk of fungal infections. Early detection and treatment with adequate early empiric therapy is the key to obtaining a better outcome in liver transplantation patients.

Characteristics of vertebral osteomyelitis after liver transplantation

We performed a retrospective single-centre 1:3 case-control study to investigate the characteristics of vertebral osteomyelitis (VO) occurring in orthotopic liver transplant (OLT) recipients between 2000 and 2012. Nine cases were identified in 752 OLT recipients (1.2%), with a median time from OLT to VO of 12 weeks. In comparison with 27 VO not occurring in OLT patients (controls), VO occurring in OLT recipients was characterized by decreased levels of inflammation biomarkers (average C-reactive protein 65.1 mg·L(-1) vs. 167 mg·L(-1), p 0.02; average white blood cell count 4.8 × 10(9)·L(-1) vs. 12.9 × 10(9)·L(-1), p < 0.001), higher rate of fungal infections (3/9 vs. 0/27, p 0.01), lower rate of bacterial infections (3/9 vs. 25/27, p 0.001) and decreased proportion of positive blood cultures (1/9 vs. 16/27, p 0.02) despite a trend towards higher rate of multifocal infection. Microbiologic outcomes were similar between the two groups. Overall, VO in OLT patients was more difficult to diagnose as a result of altered inflammation response and specific microbial epidemiology of causal microorganisms.

Targeted versus universal antifungal prophylaxis among liver transplant recipients

Guidelines recommend targeted antifungal prophylaxis for liver transplant (LT) recipients based on tiers of risk, rather than universal prophylaxis. The feasibility and efficacy of tiered, targeted prophylaxis is not well established. We performed a retrospective study of LT recipients who received targeted prophylaxis (n = 145; voriconazole [VORI; 54%], fluconazole [8%], no antifungal [38%]) versus universal VORI prophylaxis (n = 237). Median durations of targeted and universal prophylaxis were 11 and 6 days, respectively (p < 0.0001). The incidence of invasive fungal infections (IFIs) in targeted and universal groups was 6.9% and 4.2% (p = 0.34). Overall, intra-abdominal candidiasis (73%) was the most common IFI. Posttransplant bile leaks (p = 0.001) and living donor transplants (p = 0.04) were independent risk factors for IFI. IFIs occurred in 6% of high-risk transplants who received prophylaxis and 4% of low-risk transplants who did not receive prophylaxis (p = 1.0). Mortality rates (100 days) were 10% (targeted) and 7% (universal) (p = 0.26); attributable mortality due to IFI was 10%. Compliance with prophylaxis recommendations was 97%. Prophylaxis was discontinued for toxicity in 2% of patients. Targeted antifungal prophylaxis in LT recipients was feasible and safe, effectively prevented IFIs and reduced the number of patients exposed to antifungals. Bile leaks and living donor transplants should be considered high-risk indications for prophylaxis.

Randomized trial of micafungin for the prevention of invasive fungal infection in high-risk liver transplant recipients

In this randomized clinical trial comparing micafungin 100 mg with standard-care antifungal prophylaxis (fluconazole, liposomal amphotericin B, or caspofungin) in high-risk liver transplant patients, micafungin 100 mg was noninferior and had a better kidney safety profile.

Background. Invasive fungal infection (IFI) following liver transplant is associated with significant morbidity and mortality. Antifungal prophylaxis is rational for liver transplant patients at high IFI risk.

Methods. In this open-label, noninferiority study, patients were randomized 1:1 to receive intravenous micafungin 100 mg or center-specific standard care (fluconazole, liposomal amphotericin B, or caspofungin) posttransplant. The primary endpoint was clinical success (absence of a proven/probable IFI and no need for additional antifungals) at end of prophylaxis (EOP). Noninferiority (10% margin) of micafungin vs standard care was assessed in the per protocol and full analysis sets. Safety assessments included adverse events and liver and kidney function tests.

Results. The full analysis set comprised 344 patients (172 micafungin; 172 standard care). Mean age was 51.2 years; 48.0% had a Model for End-Stage Liver Disease score ≥20. At EOP (mean treatment duration, 17 days), clinical success was 98.6% for micafungin and 99.3% for standard care (Δ standard care – micafungin [95% confidence interval], 0.7% [−2.7% to 4.4%]) in the per protocol set and 96.5% and 93.6%, respectively (−2.9% [−8.0% to 1.9%]), in the full analysis set. Incidences of drug-related adverse events for micafungin and standard care were 11.6% and 16.3%, leading to discontinuation in 6.4% and 11.6% of cases, respectively. At EOP, liver function tests were similar but creatinine clearance was higher in micafungin- vs standard care–treated patients.

Conclusions. Micafungin was noninferior to standard care as antifungal prophylaxis in liver transplant patients at high risk for IFI. Adverse event profiles and liver function at EOP were similar, although kidney function was better with micafungin.

Clinical Trials Registration. NCT01058174.

Randomized, double-blind trial of anidulafungin versus fluconazole for prophylaxis of invasive fungal infections in high-risk liver transplant recipients

Invasive fungal infections (IFIs) are a common complication in liver transplant recipients. There are no previous randomized trials of an echinocandin for the prevention of IFIs in solid organ transplant recipients. In a randomized, double-blind trial conducted at University-affiliated transplant centers, 200 high-risk liver transplant recipients (100 patients per group) received either anidulafungin or fluconazole for antifungal prophylaxis. Randomization was stratified by Model for End-Stage Liver Disease score ≥30 and receipt of a pretransplant antifungal agent. The primary end point was IFI in a modified intent-to-treat analysis. The overall incidence of IFI was similar for the anidulafungin (5.1%) and the fluconazole groups (8.0%) (OR 0.61, 95% CI 0.19-1.94, p = 0.40). However, anidulafungin prophylaxis was associated with less Aspergillus colonization or infection (3% vs. 9%, p = 0.08), lower breakthrough IFIs among patients who had received pretransplant fluconazole (0% vs. 27%, p = 0.07), and fewer cases of antifungal resistance (no cases vs. 5 cases). Both drugs were well-tolerated. Graft rejection, fungal-free survival, and mortality were similar for both groups. Thus, anidulafungin and fluconazole have similar efficacy for antifungal prophylaxis in most liver transplant recipients. Anidulafungin may be beneficial if the patient has an increased risk for Aspergillus infection or received fluconazole before transplantation.

Surveillance of bacterial and fungal infections in the postoperative period following liver transplantation: a series from 2005-2011

Orthotopic liver transplantation (OLT) is a life-saving procedure for the treatment of many end-stage diseases, but infectious and acute rejection episodes remain major causes of morbidity and mortality. Bacterial and fungal infections can be due to intra-abdominal, biliary, respiratory, urinary, wound, central venous catheters (CVC) or unknown sources. Using the computerized database of our microbiology laboratory, we analyzed all the bacterial and fungal infections in the first three months following OLT among 151 consecutive adult recipients at single center between January 2005 and December 2011. Samples included blood, bile CVC, urine, and bronchoalveolar lavage (BAL) specimen. Culture and identification of the isolated microorganisms was done in accordance with standard microbiological procedures. Three hundred thirteen samples from the above sites showed positive results for gram-positive cocci (n = 137; 43.8%), gram-negative rods (n = 156; 49.8%), and Candida species (n = 19; 6.1%). One patient (0.3%) experienced a CVC-related infection caused by Fusarium oxysporum. Bacterial and particularly biliary tract infections seem to play major roles in morbidity and mortality in the first three months following OLT. The major contributors to patient morbidity and mortality were candidemia and/or invasive candidiasis mainly from the biliary tract and/or CVC-related infections.

Fungal osteomyelitis and septic arthritis

Management of fungal osteomyelitis and fungal septic arthritis is challenging, especially in the setting of immunodeficiency and conditions that require immunosuppression. Because fungal osteomyelitis and fungal septic arthritis are rare conditions, study of their pathophysiology and treatment has been limited. In the literature, evidence-based treatment is lacking and, historically, outcomes have been poor. The most common offending organisms are Candida and Aspergillus, which are widely distributed in humans and soil. However, some fungal pathogens, such as Histoplasma, Blastomyces, Coccidioides, Cryptococcus, and Sporothrix, have more focal areas of endemicity. Fungal bone and joint infections result from direct inoculation, contiguous infection spread, or hematogenous seeding of organisms. These infections may be difficult to diagnose and eradicate, especially in the setting of total joint arthroplasty. Although there is no clear consensus on treatment, guidelines are available for management of many of these pathogens.

Polymerase chain reaction melting profiles of Candida glabrata clinical isolates in solid organ transplant recipients in comparison to the other group of surgical patients

The aim of the retrospective study were to estimate the prevalence of Candida glabrata in liver and kidney transplant recipients compared to patients with short bowel syndrome receiving chronic total parenteral nutrition and relevance of the polymerase chain reaction melting profile (PCR MP) method for Candida glabrata strains differentiation. C. glabrata clinical strains isolated from patients were identified by using standard mycological procedures. The analysis of genetic relatedness of the isolated strains was conducted using the PCR MP method. The prevalence of C. glabrata comprised 29% of all episodes of fungal colonization and infection in solid organ transplant recipients, and 54% of those in hospitalized patients receiving long-term total parenteral nutrition. Among 78 isolates obtained from 55 solid organ transplant recipients and 2 organ donors, 44 different C. glabrata PCR MP fingerprints were observed. Forty-seven organ recipients and one organ donor carried unique C. glabrata strains. Among 37 isolates obtained from 31 patients receiving long-term TPN, 8 different PCR MP profiles of C. glabrata strains were observed. Two patients carried unique C. glabrata strains. Most of the C. glabrata colonization and infections in solid-organ transplant recipients were caused by endogenic strains. Most of the C. glabrata colonization and infections in hospitalized patients receiving long-term total parenteral nutrition could result by patient-to-patient transmission. The results showed that the PCR MP technique is a good discriminatory method for genotyping for C. glabrata strains.

Impact of pretransplant rifaximin therapy on early post-liver transplant infections

Bacterial and fungal infections are major causes of morbidity and mortality after liver transplantation (LT). The role of intestinal decontamination in the prevention of post-LT infections is controversial. Rifaximin is widely used for the treatment of hepatic encephalopathy. The effect of rifaximin on post-LT infections is unknown. The aim of our study was to determine the effect of rifaximin therapy in the pretransplant period on early bacterial infections (EBIs) and fungal infections within the first 30 days after LT. All adult patients who underwent LT at our institution (January 2009 to July 2011) were included in this retrospective cohort study. Patients receiving antibiotics other than pretransplant protocol antibiotics were excluded. Patients were stratified into 2 groups based on the presence or absence of rifaximin therapy for at least 2 days before LT. Infections were defined by the isolation of any bacterial or fungal organisms within 30 days of LT. Multivariate regression analysis, Student t tests, and Pearson's chi-square tests were used to compare the 2 groups. Two hundred sixty-eight patients were included, and 71 of these patients (26.5%) were on rifaximin at the time of LT. The 2 groups were comparable with respect to age, sex, race, and Model for End-Stage Liver Disease score. There were no significant differences in the rates of EBIs (30% for the non-rifaximin group and 25% for the rifaximin group, P = 0.48) or fungal infections between the 2 groups. There was no increase in antimicrobial resistance among the infecting organisms. There was no difference in survival between the rifaximin and non-rifaximin groups (98% versus 97%, P = 0.36). In conclusion, the use of rifaximin in the pre-LT period was not associated with an increased risk of bacterial or fungal infections in the early post-LT period.

Nosocomial infections within the first month of solid organ transplantation

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

Practical aspects of the management of patients with chronic hand eczema

Urgency. High prevalence ot hand eczema stipulates the urgency ot studies ot significant factors ot the torpid course ot this disease, which is a result ot the sensitizing power ot the pathogenic biota in most cases. Goal. Optimization ot the therapy ot true hand eczema associated with chronic paronychias. Materials and methods. The tollow-up study comprised 30 patients suttering trom true hand eczema associated with chronic paronychias who underwent clinical and laboratory examinations with the determination ot the severity ot eczema, skin contamination and level ot specitic anti-Candida antibodies. Results. The authors revealed an evident clinical and laboratory etticacy ot the monotherapy with the Triderm cream aimed at the elimination ot paronychias and hand eczema.

Lung transplant infection

Lung transplantation has become an accepted therapeutic procedure for the treatment of end‐stage pulmonary parenchymal and vascular disease. Despite improved survival rates over the decades, lung transplant recipients have lower survival rates than other solid organ transplant recipients. The morbidity and mortality following lung transplantation is largely due to infection‐ and rejection‐related complications. This article will review the common infections that develop in the lung transplant recipient, including the general risk factors for infection in this population, and the most frequent bacterial, viral, fungal and other less frequent opportunistic infections. The epidemiology, diagnosis, prophylaxis, treatment and outcomes for the different microbial pathogens will be reviewed. The effects of infection on lung transplant rejection will also be discussed.