Approach to the Solid Organ Transplant Patient with Suspected Fungal Infection

Trichoderma spp.-Related Pneumonia: A Case Report in Heart-Lung Transplantation Recipient and a Systematic Literature Review

Opportunistic and hospital-acquired infections are common among recipients of solid organ transplantation. New pathogens are increasingly reported in the intensive care unit (ICU) population. We report a case of a patient who developed Trichoderma spp.-related pneumonia (TRP) after heart-lung transplantation. In the absence of antifungal susceptibility testing, TRP was confirmed by histological examination, and empirical therapy with voriconazole and caspofungin was swiftly initiated. Complete resolution of pneumonia was obtained after prolonged combination therapy. Given the lack of guidelines, we conducted a systematic review to elucidate the diagnostic and therapeutic strategies to apply during Trichoderma infection. After deduplication and selection of full texts, we found 42 articles eligible for the systematic review. Pneumonia seems to be the most common clinical manifestation (31.8%). The most used antifungal therapy was amphotericin B, while combination therapy was also reported (27.3%). All the patients were immunocompromised except for one case. Despite the rarity of Trichoderma spp. infection, the increase in invasive fungal infections is of growing importance in ICU, considering their impact on mortality and the emergence of antifungal resistance. In the absence of prospective and multicenter studies, a review can provide useful insight regarding the epidemiology, clinical manifestations, and management of these unexpected challenges.

Epidemiology of Invasive Fungal Infections in Solid Organ Transplant Recipients: an Indian Perspective

Purpose of Review

This review summarizes the available Indian data on epidemiology of invasive fungal infections (IFI) in recipients of solid organ transplants (SOT). The epidemiology is further compared with studies from other parts of the world for each SOT type.

Recent Findings

The available studies on Indian epidemiology of IFI in SOT are scarce, though the number of SOTs performed in India have increased tremendously in recent years. The limited data from India present a distinct spectrum of infection in transplant recipients with high incidence of mucormycosis. During COVID-19 outbreak, IFI rate increased and renal transplant recipients acquired mucormycosis earlier than previous studies.

Summary

Maximum data on IFI was available from renal transplant recipients, wherein mucormycosis was the predominant IFI in Indian patients in contrast to invasive candidiasis in majority countries. The other IFIs had varied spectrum. With the increasing number of SOTs being performed and the already persisting high burden of IFI in India, there is an urgent need of larger prospective studies on epidemiology of IFI in transplant recipients.

Central nervous system infections after solid organ transplantation

PURPOSE OF REVIEW

Significant advances to our understanding of several neuroinfectious complications after a solid organ transplant (SOT) have occurred in the last few years. Here, we review the central nervous system (CNS) infections that are relevant to SOT via a syndromic approach with a particular emphasis on recent updates in the field.

RECENT FINDINGS

A few key studies have advanced our understanding of the epidemiology and clinical characteristics of several CNS infections in SOT recipients. Risk factors for poor prognosis and protective effects of standard posttransplant prophylactic strategies have been better elucidated. Newer diagnostic modalities which have broad clinical applications like metagenomic next-generation sequencing, as well as those that help us better understand esoteric concepts of disease pathogenesis have been studied. Finally, several studies have provided newer insights into the treatment of these diseases.

SUMMARY

Recent findings reflect the steady progress in our understanding of CNS infections post SOT. They provide several avenues for improvement in the prevention, early recognition, and therapeutic outcomes of these diseases.

Diagnosis of Pneumonia Due to Invasive Molds

Pneumonia is the most common presentation of invasive mold infections (IMIs), and is pathogenetically characterized as angioinvasion by hyphae, resulting in tissue infarction and necrosis. Aspergillus species are the typical etiologic cause of mold pneumonia, with A. fumigatus in most cases, followed by the Mucorales species. Typical populations at risk include hematologic cancer patients on chemotherapy, bone marrow and solid organ transplant patients, and patients on immunosuppressive medications. Invasive lung disease due to molds is challenging to definitively diagnose based on clinical features and imaging findings alone, as these methods are nonspecific. Etiologic laboratory testing is limited to insensitive culture techniques, non-specific and not readily available PCR, and tissue biopsies, which are often difficult to obtain and impact on the clinical fragility of patients. Microbiologic/mycologic analysis has limited sensitivity and may not be sufficiently timely to be actionable. Due to the inadequacy of current diagnostics, clinicians should consider a combination of diagnostic modalities to prevent morbidity in patients with mold pneumonia. Diagnosis of IMIs requires improvement, and the availability of noninvasive methods such as fungal biomarkers, microbial cell-free DNA sequencing, and metabolomics-breath testing could represent a new era of timely diagnosis and early treatment of mold pneumonia.

Breakthrough invasive fungal infection after liver transplantation in patients on targeted antifungal prophylaxis: A prospective multicentre study

Objective

To investigate the rate of and the risk factors for breakthrough‐IFI (b‐IFI) after orthotopic liver transplantation (OLT) according to the new definition proposed by Mycoses‐Study‐Group‐Education‐and‐Research‐Consortium (MSG‐ERC) and the European‐Confederation‐of‐Medical‐Mycology (ECMM).

Methods

Multicenter prospective study of adult patients who underwent OLT at three Italian hospitals, from January 2015 to December 2018. Targeted antifungal prophylaxis (TAP) protocol was developed and shared among participating centers. Follow‐up was 1‐year after OLT. B‐IFI was defined as infection occurring during exposure to antifungal prophylaxis. Risk factors for b‐IFI were analyzed among patients exposed to prophylaxis by univariable analysis.

Results

We enrolled 485 OLT patients. Overall compliance to TAP protocol was 64.3%, 220 patients received antifungal prophylaxis, 172 according to TAP protocol. Twenty‐nine patients were diagnosed of IFI within 1 year after OLT. Of them, 11 presented with b‐IFI within 17 (IQR 11‐33) and 16 (IQR 4‐30) days from OLT and from antifungal onset, respectively. Then out of 11 patients with b‐IFI were classified as having high risk of IFI and were receiving anti‐mould prophylaxis, nine with echinocandins and one with polyenes. Comparison of patients with and without b‐IFI showed significant differences for prior Candida colonization, need of renal replacement therapy after OLT, re‐operation, and CMV infection (whole blood CMV‐DNA >100 000 copies/mL). Although non‐significant, a higher rate of b‐IFI in patients on echinocandins was observed (8.2% vs 1.8%, P = .06).

Conclusions

We observed 5% of b‐IFI among OLT patients exposed to antifungal prophylaxis. The impact of echinocandins on b‐IFI risk in this setting should be further explored.

Successful Treatment of Pulmonary Cryptococcosis in a Liver Transplant Recipient Before and After Liver Transplant: Case Report and Literature Review

Cryptococcosis is the third most common invasive fungal infection in solid-organ transplant recipients. Patients with cirrhosis are susceptible to pretransplant cryptococcosis infections. Outcomes and optimal treatment of patients with cirrhosis who develop pulmonary cryptococcosis before and after liver transplant are still not defined. Here, we describe a case of cholestatic cirrhosis in a 50-year-old woman with a pretransplant asymptomatic pulmonary nodule. She had taken steroids for more than 1 year before she was admitted to our hospital. This asymptomatic case with a lung nodule was detected via an abnormal chest computed tomography. Cryptococcal pneumonia was diagnosed according to lung biopsy results. Testing for cryptococcal antigens was negative in the serum. The patient received antifungal therapy with amphotericin B followed by oral fluconazole, which was then followed by liver transplant. After antifungal therapy with fluconazole posttransplant, a sustained clinical response was achieved. After literature review of patients with pulmonary cryptococcosis before and after liver transplant, we identified previously reported cases with pulmonary cryptococcosis that resembled lung nodule on imaging. In this report, we aimed to raise the awareness of unrecognized pretransplant cryptococ-cosis infections in patients with cirrhosis who are waiting for liver transplant and showed the successful management of a patient with pretransplant pulmonary cryptococcosis.

Immunosuppression-related neurological disorders in kidney transplantation

A large number of neurological disorders can affect renal transplant recipients, potentially leading to disabling or life-threatening complications. Prevention, early diagnosis and appropriate management of these conditions are critical to avoid irreversible lesions. A pivotal role in the pathogenesis of common post-transplant neurological disorders is played by immunosuppressive therapy. The most frequently administered regimen consists of triple immunosuppression, which comprises a calcineurin inhibitor (CNI), a purine synthesis inhibitor and glucocorticoids. Some of these immunosuppressive drugs may lead to neurological signs and symptoms through direct neurotoxic effects, and all of them may be responsible for the development of tumors or opportunistic infections. In this review, after a brief summary of neurotoxic pathogenetic mechanisms encompassing recent advances in the field, we focus on the clinical presentation of more common and severe immunosuppression-related neurological complications, classifying them by characteristics of urgency and anatomic site. Our goal is to provide a general framework that addresses such clinical issues with a multidisciplinary approach, as these conditions require.

Invasive fungal disease in humans: are we aware of the real impact?

Despite the medical advances and interventions to improve the quality of life of those in intensive care, people with cancer or severely immunocompromised or other susceptible hosts, invasive fungal diseases (IFD) remain severe and underappreciated causes of illness and death worldwide. Therefore, IFD continue to be a public health threat and a major hindrance to the success of otherwise life-saving treatments and procedures. Globally, hundreds of thousands of people are affected every year with Candida albicans, Aspergillus fumigatus, Cryptococcus neoformans, Pneumocystis jirovecii, endemic dimorphic fungi and Mucormycetes, the most common fungal species causing invasive diseases in humans. These infections result in morbidity and mortality rates that are unacceptable and represent a considerable socioeconomic burden. Raising the general awareness of the significance and impact of IFD in human health, in both the hospital and the community, is hence critical to understand the scale of the problem and to raise interest to help fighting these devastating diseases.

How can we optimise antifungal use in a solid organ transplant centre? Local epidemiology and antifungal stewardship implementation: A single-centre study

PURPOSE

We aimed to implement and to assess the impact of the antifungal stewardship programme (AFSp) on prescription appropriateness of antifungals, management and outcomes of candidaemia patients, and antifungal consumption and costs at our solid organ transplant (SOT) institute.

METHODS

Local epidemiology of invasive fungal infections (IFIs) from 2009 to 2017 was analysed in order to prepare an effective AFSp, implemented in January 2018. It included suspension of empirical antifungal prescriptions after 72 hours (antifungal time-out), automated alert and infectious disease (ID) consult for empirical prescriptions and for every patient with IFI, and indication for step-down to oral fluconazole when possible. We used process measures and results measures to assess the effects of the implemented programme.

RESULTS

The ASFp led to significant improvements in selection of the appropriate antifungal (40.5% in pre-AFS vs 78.6% in post-AFS), correct dosing (51.2% vs 79.8%), correct length of treatment (55.9% vs 75%) and better management of patients with candidaemia. Analysis of prescribed empirical antifungal revealed that defined daily doses (DDDs) per 100 patient days decreased by 36.7% in 2018 compared to the average of pre-AFSp period, with important savings in costs.

CONCLUSION

This AFSp led to a better use of antifungal drugs in terms of appropriateness and consumption, with stable clinical and microbiological outcomes in patients with IFI.

Frequency of Invasive Fungal Disease in Adults: Experience of a Specialized Laboratory in Medellín, Colombia (2009-2015)

Invasive fungal diseases (IFD) contribute significantly to worldwide morbidity and mortality, but their frequency is not well-described in some countries. The present work describes the frequency of IFD in a specialized laboratory in Colombia. A retrospective, descriptive study was implemented between March 2009 and December 2015. Results: 13,071 patients with clinical suspicion of IFD were referred during the study period, from which 33,516 biological samples were processed and analyzed using 14 laboratory methods. Diagnosis was confirmed in 1425 patients (11%), distributed according to the mycoses of interest analyzed here: histoplasmosis in 641/11,756 patients (6%), aspergillosis in 331/10,985 patients (3%), cryptococcosis in 239/8172 patients (3%), pneumocystosis in 111/1651 patients (7%), paracoccidioidomycosis in 60/10,178 patients (0.6%), and invasive candidiasis in 48/7525 patients (0.6%). From the first year of the study period to the last year, there was a 53% increase in the number of cases of IFD diagnosed. Our laboratory experienced a high frequency of IFD diagnosis, possibly attributable to the availability of a greater range of diagnostic tools. Frequency of IFD in this study was atypical compared with other studies, probably as a result of the single laboratory-site analysis. This demonstrates that implementing educational strategies helps to create a high index of clinical suspicion, while the availability and utilization of appropriate diagnostic assays assure greater reliability in identification of these cases.

Cornely O, Kurzai O. Invasive Fungal Infection

BACKGROUND

The incidence of invasive fungal infection is approximately 6 cases per 100 000 persons per year. It is estimated that only half of such infections are detected during the patient's lifetime, making this one of the more common overlooked causes of death in intensive-care patients. The low detection rate is due in part to the complexity of the diagnostic work-up, in which the clinical, radiological, and microbiological findings must be considered. Fungi with resistance to antimycotic drugs have been found to be on the rise around the world.

METHODS

This review is based on pertinent publications retrieved from a selective search in PubMed, with special attention to guidelines on the diagnosis and treatment of invasive fungal infections caused by Candida spp., Aspergillus spp., Mucorales, and Fusarium spp.

RESULTS

The clinical risk factors for invasive fungal infection include, among others, congenital immune deficiency, protracted (>10 days) marked granulocytopenia (<0.5 x 109/L), allogeneic stem-cell transplantation, and treatment with immunosuppressive drugs or corticosteroids. High-risk groups include patients in intensive care and those with structural pulmonary disease and/or compli- cated influenza. The first line of treatment, supported by the findings of randomized clinical trials, consists of echinocandins for in- fections with Candida spp. (candidemia response rates: 75.6% for anidulafungin vs. 60.2% for fluconazole) and azole antimycotic drugs for infections with Aspergillus spp. (response rates: 52.8% for voriconazole vs. 31.6% for conventional amphotericin B). The recommended first-line treatment also depends on the local epidemiology. This challenge should be met by interdisciplinary collaboration. Therapeutic decision-making should also take account of the often severe undesired effects of antimycotic drugs (including impairment of hepatic and/or renal function) and the numerous interactions that some of them have with other drugs.

CONCLUSION

Invasive fungal infections are often overlooked in routine hospital care. They should be incorporated into antimicro- bial stewardship programs as an essential component. There is also a pressing need for the development of new classes of antimycotic drug.

Fungal infections in solid organ transplantation: An update on diagnosis and treatment

Invasive fungal infections constitute an important cause of morbidity and mortality in solid organ transplantation recipients. Since solid organ transplantation is an effective therapy for many patients with end-stage organ failure, prevention and treatment of fungal infections are of vital importance. Diagnosis and management of these infections, however, remain difficult due to the variety of clinical symptoms in addition to the lack of accurate diagnostic methods. The use of fungal biomarkers can lead to an increased diagnostic accuracy, resulting in improved clinical outcomes. The evidence for optimal prophylactic approaches remains inconclusive, which results in considerable variation in the administration of prophylaxis. The implementation of a standard protocol for prophylaxis remains difficult as previous treatment regimens, which can alter the distribution of different pathogens, affect the outcome of antifungal susceptibility testing. Furthermore, the increasing use of antifungals also contributes to incremental costs and the risk of development of drug resistance. This review will highlight risk factors, clinical manifestations and timing of fungal infections and will focus predominately on the current evidence for diagnosis and management of fungal infections.

Neurologic Complications of Transplantation

PURPOSE OF REVIEW

This article describes the diagnosis and management of neurologic problems during hematopoietic cell and solid organ transplantation using time elapsed since transplantation as a guide to expected complications, including drug toxicities, infections, strokes, autoimmune phenomena, disease recurrence, and secondary neoplasms.

RECENT FINDINGS

Growing clinical experience in the neurology of transplantation has led to appreciation of the diverse clinical and radiographic spectrum of calcineurin inhibitor-related posterior reversible encephalopathy syndrome (PRES) and progressive multifocal leukoencephalopathy. Novel autoimmune phenomena illustrate the delicate balance between adequate immunosuppression and necessary host inflammatory defenses that can lead to organ rejection. The spectrum of infectious complications has changed with the evolution of new conditioning regimens.

SUMMARY

Neurologic problems remain an important source of morbidity and mortality, both in the immediate transplantation period and for years after the procedure. As perioperative management has reduced the incidence of acute infections, graft versus host disease, and organ rejection, problems of long-term survivors require neurologic input into multidisciplinary management of chronic neurologic conditions impacting quality of life.

Presence of Candida spp. and candidiasis in liver transplant patients

BACKGROUND

Candidiasis is the most common opportunistic fungal infection of the oral cavity caused by fungi of the genus Candida and usually associated with immunosuppressed individuals.

OBJECTIVES

To evaluate the presence of oral candidiasis and identify the presence of Candida spp. in liver transplant recipients and assess the association between the presence of the fungus and sociodemographic variables, dietary habits and environmental exposure.

METHODS

A cross-sectional study was performed with 49 patients who had undergone liver transplants at Hospital São Vicente de Paulo in Passo Fundo - RS. Patient information was collected to obtain sociodemographic data, eating habits and environmental exposure. Fungal infections were screened by oral clinical examination and the presence of Candida spp by the collection of oral samples with a sterile swab, seeded in Sabouraud Dextrose Agar, incubated at 25°C and observed at 48 hours. To identify Candida albicans, the germ tube test was performed.

RESULTS

In 49 patient samples, 39% had the yeast of the genus Candida isolated and, of these patients, 12% had candidiasis, 66% of atrophic type and 34% pseudomembranous. Eleven yeast species were (58%) Candida non-albicans and eight (42%) Candida albicans.

STUDY LIMITATIONS

The present study presents as a limitation the inclusion of patients in different stages of immunosuppression.

CONCLUSION

The high incidence of Candida non-albicans in the oral cavity of transplant patients with a long period of transplantation is warning to a more effective control of the health of these individuals, especially those with older age.

Early-onset de novo invasive pulmonary aspergillosis in an orthotopic heart transplant recipient

Invasive aspergillosis generally occurs during the first 1-6 months after heart transplantation. It has been rarely seen in the first 2 weeks postcardiac transplant. We herein describe a unique case of invasive pulmonary aspergillosis (IPA) diagnosed on day 9 postorthotopic heart transplantation. The known risk factors for IPA in cardiac transplant recipients were not identified in our case. The organ recipients from the same donor did not report Aspergillus infection. Hospital environmental samplings failed to demonstrate Aspergillus spores in the patient's room and his adjacent rooms. A diagnosis of early-onset de novo IPA was made. The patient initially received combined antifungal therapy (voriconazole plus micafungin), followed by voriconazole maintenance monotherapy with favorable clinical outcome.