Pulmonary infections in transplant recipients

Invasive Aspergillosis after Renal Transplantation

Over 95,000 renal transplantation procedures were completed in 2021. Invasive aspergillosis (IA) affects about 1 in 250 to 1 in 43 renal transplant recipients. About 50% of cases occur in the first 6 months after transplantation; the median time of onset is nearly 3 years. Major risk factors for IA include old age, diabetes mellitus (especially if prior diabetic nephropathy), delayed graft function, acute graft rejection, chronic obstructive pulmonary disease, cytomegalovirus disease, and neutropenia. Hospital construction, demolition activities, and residential refurbishments also increase the risk. Parenchymal pulmonary infection is the most common (~75%), and bronchial, sinus, cerebral, and disseminated disease are less common. Typical pulmonary features of fever, dyspnea, cough, and hemoptysis are seen in most patients, but 20% have non-specific general features of illness. Non-specific infiltrates and pulmonary nodules are the commonest radiological features, with bilateral disease carrying a worse prognosis. Bronchoscopy for direct microscopy, fungal culture, and Aspergillus antigen are the fastest means of establishing the diagnosis; a positive serum Aspergillus antigen presages a worse outcome. Standard therapy includes voriconazole, isavuconazole, or posaconazole, with great attention necessary to assess likely drug-drug interactions. Liposomal amphotericin B and echinocandins are less effective. A reduction in or stopping immunosuppression needs careful consideration, given the overall mortality of IA in renal-transplanted patients; continuing corticosteroid after the diagnosis of IA increases mortality by 2.5 times. Surgical resection or the addition of a gamma interferon should also be considered.

Pulmonary Complications in Renal Transplant Recipients

Background Kidney transplantation recipients are at an increased risk of lung complications due to infectious or non-infectious reasons. We aimed to determine the lung complications after transplantation and what we could do to prevent the complications during the follow-up, retrospectively. Material and Methods The 296 patients who underwent kidney transplantation surgery in our centre between the years 1999 to 2006 were included in the study. Results 75% of the patients were male (n: 222). 77% of the patients (n: 228) had a living-related donor. The mean hospitalisation duration in the post-transplantation period was 13.3±9.07 days. During the follow-up, 37.2% of the patients (n: 110) had rejection, and pulse steroid treatments were given to the 74.5% of these patients. In our study, the lung complication development ratio was 16.2%, and 84% of these complications were due to infections. A specific aetiology was not identified in 63.5% of patients. The patients with a living-related donor had more lung complications due to infection (p

Posttransplant Pneumonia Among Solid Organ Transplant Recipients Followed in Intensive Care Unit

OBJECTIVES

Pneumonia is a significant cause of morbidity and mortality in solid-organ transplant recipients. We studied the demographic characteristics, respiratory management, and outcomes of solid-organ transplant recipients with pneumonia in an intensive care unit.

MATERIALS AND METHODS

There have been 2857 kidney, 687 liver, and 142 heart transplants performed between October 16, 1985, and February 28, 2021, at our center. We retrospectively analyzed records for 51 of 193 recipients with pneumonia during the posttransplant period between January 1, 2016, and December 31, 2018.

RESULTS

Fifty-one of 193 recipients were followed in the intensive care unit. Mean age was 45.4 ± 16.6 years among 42 male (82.4%) and 9 female (17.6%) recipients. Twenty-six patients (51%) underwent kidney transplant, 14 (27.5%) liver transplant, 7 (13.7%) heart transplant, and 4 (7.8%) combined kidney and liver transplant. Most pneumonia episodes occurred 6 months after transplant (70.6%) with acute hypoxemic respiratory failure. Mean Acute Physiology and Chronic Health Evaluation System II score was 18.9 ± 7.7, and the Sequential Organ Failure Assessment score was 8.5 ± 3.9 at intensive care unit admission. Whereas 66.7% of pneumonia cases were nosocomial acquired, 33.3% were community acquired. The intensive care unit and 28-day mortality rates were 39.2% and 64.7%, respectively.

CONCLUSIONS

Solid-organ transplant recipients with pneumonia have been associated with poor prognosis. Our cohort followed in the intensive care unit comprised mostly patients with nosocomial pneumonia with acute hypoxemic respiratory failure, hospitalized 6 months after transplant with high Acute Physiology and Chronic Health Evaluation System II scores predictive of mortality. In this high-risk patient group, careful follow-up, early discovery of warning signs, and rapid treatment initiation could improve the outcomes in the intensive care unit.

Prevalence surveillance of healthcare-associated infections at a Tunisianonco-hematology ward

Background : Healthcare-associated infections (HAIs) are with high rates of mortality and an additional cost, in onco-hematology patients.

Aim : The study aims to assess the prevalence trends of HAIs in the onco-hematology ward of the Tunisian National Bone Marrow Transplant Center (NBMTC), and to determine the principal associated risk factors.

Methods: Six repeated point prevalence surveys were conducted, from May 2018 to March 2019, using a two months interval. All patients hospitalized in the day of the survey were included. Risk factors of HAIs were expressed as odds ratios (ORs) with 95% confidence intervals (CIs). They were assessed using a logistic regression model.

Results: Nineteen patients out of a total of 74 patients have been diagnosed with 19 HAIs, representing a prevalence of 25.7%. No significant downward or upward trend of prevalence was revealed over time (p=0.3). The most common HAI was respiratory tract infection (57.9%) with a prevalence of 14.9%. Multiple logistic regression analysis revealed that HAI was significantly associated with neutropenia (Adjusted OR: 14; 95% CI: 1.5-127; p=0.01) and duration of central venous catheter (Adjusted OR: 1.1; 95% CI: 1-1.2; p=0.005).

Conclusion: High prevalence of HAIs in our center with a high rate of mortality, requiring identifying potential problems in infection control practices.

Acute Respiratory Failure in Renal Transplant Recipients: A Single Center Experience

OBJECTIVES

We evaluated the frequency and cause of acute respiratory failure in renal transplant recipients.

MATERIALS AND METHODS

Our single-center retrospective observational study included consecutive renal transplant recipients who were admitted to an intensive care unit for acute respiratory failure between 2011 and 2017. Acute respiratory failure was defined as oxygen saturation < 92% or partial pressure of oxygen in arterial blood < 60 mm Hg on room air and/or requirement of noninvasive or invasive mechanical ventilation.

RESULTS

Of 187 renal transplant recipients, 35 (18.71%) required intensive care unit admission; 11 of these patients (31.4%) were admitted to the intensive care unit with acute respiratory failure. Six of these patients (54.5%) had pneumonia and had shown infiltrates on chest radiography, which were shown in a minimum of 3 zones of the lung (2 with Klebsiella pneumonia, 1 with Acinetobacter species, 1 with Proteus mirabilis, 2 with no microorganisms). The other reasons for acute respiratory failure were cardiogenic pulmonary edema (2 patients), acute respiratory distress syndrome (2 patients, due to acute pancreatitis and acute cerebrovascular thromboembolism), and exacerbation of chronic obstructive pulmonary disease (1 patient). Six patients (54.5%) needed invasive mechanical ventilation because of pneumonia (3 patients), cardiogenic pulmonary edema (2 patients), and cerebrovascular thromboembolism (1 patient). Hemodialysis was administered in 5 patients (45%). Six of 11 patients died due to pneumonia (3 p atients), cardiogenic pulmonary edema (2 patients), and cerebrovascular thromboembolism (1 patient). Among the 5 survivors, 3 (60%) had recovered previous graft function.

CONCLUSIONS

Acute respiratory failure is associated with high mortality and morbidity in renal transplant recipients. Main causes of acute respiratory failure were bacterial pneumonia and cardiogenic pulmonary edema in our study population. Extended chemoprophylaxis for bacterial and fungal infection and early intensive care unit admission of patients with acute respiratory failure may improve outcomes.

Is hospital-acquired pneumonia different in transplant recipients?

Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) are serious complications in transplant patients. The aim of this review is to summarize the evidence regarding nosocomial pneumonia in transplant recipients, including HAP in non-ventilated patients and VAP, and to identify future directions for improvement.A comprehensive literature search in the PubMed/MEDLINE database was performed. Articles written in English and published between 1990 and November 2018 were included. HAP/VAP in transplant patients usually occurs early post-transplant, particularly during neutropenia in haematopoietic stem cell transplant recipients. Bacteria are the leading cause of nosocomial pneumonia for both immunocompetent and transplant recipients, being Gram negative organisms, and especially Pseudomonas aeruginosa, highly prevalent. Multidrug-resistant bacteria are of special concern. Pneumonia in the transplant setting may be caused by opportunistic pathogens, and the differential diagnosis needs to be extended to other non-infectious complications. The most relevant opportunistic pathogens are Aspergillus fumigatus, Pneumocystis jirovecii and cytomegalovirus. Nevertheless, they are an exceptional cause of nosocomial pneumonia, and usually occur in severely immunosuppressed patients not receiving antimicrobial prophylaxis. Performing bronchoalveolar lavage may improve the rate of aetiological diagnosis, leading to a change in therapeutic management and improved outcomes. The optimal length of antibiotic therapy for bacterial HAP/VAP has not been well defined, but it should perhaps be longer than in the general population. Mortality associated with HAP/VAP is high. HAP/VAP in transplant patients is frequent and is associated with increased mortality. There is room for improvement in gaining knowledge about the management of HAP/VAP in this population.

Diagnostic and therapeutic approach to infectious diseases in solid organ transplant recipients

Purpose

Prognosis of solid organ transplant (SOT) recipients has improved, mainly because of better prevention of rejection by immunosuppressive therapies. However, SOT recipients are highly susceptible to conventional and opportunistic infections, which represent a major cause of morbidity, graft dysfunction and mortality.

Methods

Narrative review.

Results

We cover the current epidemiology and main aspects of infections in SOT recipients including risk factors such as postoperative risks and specific risks for different transplant recipients, key points on anti-infective prophylaxis as well as diagnostic and therapeutic approaches. We provide an up-to-date guide for management of the main syndromes that can be encountered in SOT recipients including acute respiratory failure, sepsis or septic shock, and central nervous system infections as well as bacterial infections with multidrug-resistant strains, invasive fungal diseases, viral infections and less common pathogens that may impact this patient population.

Conclusion

We provide state-of the art review of available knowledge of critically ill SOT patients with infections.

Severe infections in critically ill solid organ transplant recipients

BACKGROUND

Severe infections are among the most common causes of death in immunocompromised patients admitted to the intensive care unit. The epidemiology, diagnosis and treatment of these infections has evolved in the last decade.

AIMS

We aim to provide a comprehensive review of these severe infections in this population.

SOURCES

Review of the literature pertaining to severe infections in critically ill solid organ transplant recipients. PubMed and Embase databases were searched for documents published since database inception until November 2017.

CONTENT

The epidemiology of severe infections has changed in the immunocompromised patients. This population is presenting to the intensive care unit with specific transplantation procedure-related infections, device-associated infections, a multitude of opportunistic viral infections, an increasing number of nosocomial infections and bacterial diseases with a more limited therapeutic armamentarium. Both molecular diagnostics and imaging techniques have had substantial progress in the last decade, which will, we hope, translate into faster and more precise diagnoses, as well as more optimal empirical treatment de-escalation.

IMPLICATIONS

The key clinical elements to improve the outcome of critically ill solid organ transplant recipients depend on the knowledge of geographic epidemiology, specific surgical procedures, net state of immunosuppression, hospital microbial ecology, aggressive diagnostic strategy and search for source control, rapid initiation of antimicrobials and minimization of iatrogenic immunosuppression.

Pneumonia in Renal Transplant Recipients: A Single-Center Study

OBJECTIVES

Pulmonary infections are a significant cause of morbidity and mortality in solid-organ transplant recipients despite enhanced facilities for perioperative care. The aim of this study was to evaluate the demographic characteristics, clinical course, and outcomes of renal transplant recipients with pneumonia.

MATERIALS AND METHODS

The medical records of all renal transplant recipients from January 2010 to December 2014 were retrospectively reviewed, and patients diagnosed with pneumonia according to Centers for Disease Control and Prevention criteria were evaluated. Pneumonia was classified as community acquired or nosocomial. Patient demographics, microbiologic findings, need for intensive care/mechanical ventilation over the course of treatment, and information about clinical follow-up and mortality were all recorded.

RESULTS

Eighteen (13.4%) of 134 renal transplant recipients had 25 pneumonia episodes within the study period. More than half (56%) of the pneumonia episodes developed within the first 6 months of transplant, whereas 44% developed after 6 months (all > 1 year). Eight cases (32%) were considered nosocomial pneumonia, and 17 (68%) were considered community-acquired pneumonia. Bacteria were the most common cause of pneumonia (28%), and fungi ranked second (8%). No viral or mycobacterial agents were detected. No patients required prolonged mechanical ventilation. No statistically significant difference was found in the need for intensive care or regarding mortality between patients with nosocomial and community-acquired pneumonia. Two patients (11%) died, and all remaining patients recovered.

CONCLUSIONS

The present study confirmed that pneumonia after renal transplant is not a rare complication but a significant cause of morbidity. Long-term and close follow-up for pneumonia is necessary after renal transplant.

Early infections in the intensive care unit after liver transplantation-etiology and risk factors: A single-center experience

BACKGROUND

Infectious complications represent one of the main causes of perioperative morbidity and mortality of liver transplant recipients. The primary objective of this retrospective observational study was to evaluate incidence and etiology of early (within 1 month from surgery and occurring in the intensive care unit [ICU]) postoperative infections as well as donor- and recipient-related risk factors.

METHODS

The data of 280 patients undergoing 299 consecutive liver transplant procedures from January 2012 to December 2015 were extracted from the Italian ICU registry database and hospital registries. Perioperative risk factors, etiology of infections, and antibiotic susceptibility of isolated microorganisms were taken into consideration.

RESULTS

Global incidence of postoperative infections was 21%. Pneumonia was the most frequent infection and, globally, gram-negative bacteria were the most common agents. Septic shock was present in 22% of infection cases and hospital mortality was higher in patients with postoperative infection. Preoperative chronic obstructive pulmonary disease, malnutrition, preoperative ascites, encephalopathy, and early re-transplantation were significantly associated to post orthotopic LT infections.

CONCLUSION

Infections represent a major cause of early postoperative morbidity and mortality. The impact of single risk factors and the results of their preoperative management should be further investigated in order to reduce the incidence and evolution of postoperative infections.

Sepsis and Challenging Infections in the Immunosuppressed Patient in the Intensive Care Unit

In 2017, most intensive care units (ICUs) worldwide are admitting a growing population of immunosuppressed patients. The most common causes of pre-ICU immunosuppression are solid organ transplantation, hematopoietic stem cell transplantation, and infection due to human immunodeficiency virus. In this article, the authors review the most frequent infections that cause critical care illness in each of these 3 immunosuppressed patient populations.

Lower Respiratory Tract Infections

This review will focus on the infectious etiologies and more common noninfectious causes of lower respiratory tract syndromes among major immunosuppressed populations. The changing epidemiology of infections in the era of highly active antiretroviral therapy (HAART) in the case of HIV-positive patients and the impacts of both newer immune-suppressant therapies and anti-infective prophylaxis for other immunocompromised hosts will be discussed, with emphasis on diagnostic approaches and practice algorithms.

Acute Respiratory Failure in Renal Transplant Recipients: A Single Intensive Care Unit Experience

OBJECTIVES

Frequency of pulmonary complications after renal transplant has been reported to range from 3% to 17%. The objective of this study was to evaluate renal transplant recipients admitted to an intensive care unit to identify incidence and cause of acute respiratory failure in the postoperative period and compare clinical features and outcomes between those with and without acute respiratory failure.

MATERIALS AND METHODS

We retrospectively screened the data of 540 consecutive adult renal transplant recipients who received their grafts at a single transplant center and included those patients admitted to an intensive care unit during this period for this study. Acute respiratory failure was defined as severe dyspnea, respiratory distress, decreased oxygen saturation, hypoxemia or hypercapnia on room air, or requirement of noninvasive or invasive mechanical ventilation.

RESULTS

Among the 540 adult renal transplant recipients, 55 (10.7%) were admitted to an intensive care unit, including 26 (47.3%) admitted for acute respiratory failure. Median time from transplant to intensive care unit admission was 10 months (range, 0-67 mo). The leading causes of acute respiratory failure were bacterial pneumonia (56%) and cardiogenic pulmonary edema (44%). Mean partial pressure of arterial oxygen to fractional inspired oxygen ratio was 174 ± 59, invasive mechanical ventilation was used in 13 patients (50%), and noninvasive mechanical ventilation was used in 8 patients (31%). The overall mortality was 16.4%.

CONCLUSIONS

Acute respiratory failure was the reason for intensive care unit admission in almost half of our renal transplant recipients. Main causes of acute respiratory failure were bacterial pneumonia and cardiogenic pulmonary edema. Mortality of patients admitted for acute respiratory failure was similar to those without acute respiratory failure.

Cavitary lung lesion 6 years after renal transplantation

The differential diagnoses of a cavitary lung lesion in renal transplant recipients would include infection, malignancy and less commonly inflammatory diseases. Bacterial infection, Tuberculosis, Nocardiosis, fungal infections like Aspergillosis and Cryptococcosis need to be considered in these patients. Pulmonary cryptococcosis usually presents 16-21 mo after transplantation, more frequently in patients who have a high level of cumulative immunosuppression. Here we discuss an interesting patient who never received any induction/anti-rejection therapy but developed both BK virus nephropathy as well as severe pulmonary Cryptococcal infection after remaining stable for 6 years after transplantation. This case highlights the risk of serious opportunistic infections even in apparently low immunologic risk transplant recipients many years after transplantation.

Long-term pulmonary infections in heart transplant recipients

OBJECTIVES

Pulmonary infections are life-threatening complications in heart transplant recipients. Our aim was to evaluate long-term pulmonary infections and the effect of prophylactic antimicrobial strategies on time of occurrence of pulmonary infections in heart transplant recipients.

MATERIALS AND METHODS

Patients who underwent heart transplantation between 2003 and 2013 at Baskent University were reviewed. Demographic information and data about immunosuppression and infectious episodes were collected.

RESULTS

In 82 heart transplant recipients (mean age, 33.85 y; 58 male and 24 female), 13 recipients (15.8%) developed pulmonary infections (mean age, 44.3 y; 9 male and 4 female). There were 12 patients who had dilated cardiomyopathy and 1 patient who had myocarditis before heart transplantation; 12 patients received immunosuppressive therapy in single or combination form. Pulmonary infections developed in the first month (1 patient), from first to third month (6 patients), from third to sixth month (1 patient), and > 6 months after transplantation (5 patients). Chest computed tomography showed consolidation (unilateral, 9 patients; bilateral, 4 patients). Multiple nodular consolidations were observed in 2 patients and a cavitary lesion was detected in 1 patient. Bronchoscopy was performed in 6 patients; 3 patients had Aspergillus fumigatus growth in bronchoalveolar lavage fluid, and 2 patients had Acinetobacter baumannii growth in sputum. Treatment was empiric antibiotics (6 patients), antifungal drugs (5 patients), and both antibiotics and antifungal drugs (2 patients); treatment period was 1-12 months in patients with invasive pulmonary aspergillosis.

CONCLUSIONS

Pulmonary infections are the most common cause of mortality in heart transplant recipients. A. fumigatus is the most common opportunistic pathogen. Heart transplant recipients with fever and cough should be evaluated for pulmonary infections, and invasive pulmonary aspergillosis should be suspected if these symptoms occur within the first 3 months. Immediately starting an empiric antibiotic is important in treating pulmonary infections in heart transplant recipients.

Importance of radiological detection of early pulmonary acute complications of liver transplantation: analysis of 259 cases

PURPOSE

Pulmonary complications are common causes of morbidity and mortality after orthotopic liver transplantation (OLT) and consist of atelectasis, pleural effusion, pulmonary oedema, adult respiratory distress syndrome (ARDS) and pneumonia. The aim of this paper is to describe the incidence of pulmonary complications after OLT during the first postoperative week and to evaluate the informative value of the chest X-ray (CXR) in clinical practice.

MATERIALS AND METHODS

Patients who underwent OLT at the Ancona Transplant Centre between August 2005 and August 2012 were included in this retrospective study. The CXR and, if performed, the thoracic computed tomography (TCT) scans performed during the first 7 postoperative days were reviewed, and the radiological findings for atelectasis, pleural effusion, pulmonary oedema, ARDS and pneumonia were independently assessed and quantified by two radiologists according to the Fleischner Society criteria. Cases of pneumothorax after thoracentesis were assessed. Development of pneumonia was defined as the simultaneous presence of positive CXR or TCT and positive serological or fluid samples and clinical symptoms; the prevalence of infectious agents was assessed. The radiological reports produced in the clinical setting were compared with the findings.

RESULTS

Among 259 patients included, atelectasis was observed in 227 patients (87.6 %); pleural effusion in 250 (96.5 %); pulmonary oedema in 204 (78 %); ARDS in seven patients (2.6 %); and pneumothorax in 37 patients (14 %). Pneumonia occurred in 32 cases (12.3 %). Pulmonary oedema was underestimated in the radiological reports in 104 cases (40 %).

CONCLUSIONS

Knowledge about postoperative pulmonary complications and collaboration between the radiologist and clinician are essential for improving the management of OLT recipients.

Respiratory tract infections in the immunocompromised

PURPOSE OF REVIEW

Pulmonary infections are particularly common in the immunosuppressed host. This review discusses emerging threats, newer modalities of diagnostic tests and emerging treatment options, and also highlights the increasing problem of antimicrobial resistance.

RECENT FINDINGS

Nosocomial pneumonia is increasingly due to multidrug-resistant Gram-negative organisms in immunosuppressed patients. Viral pneumonias remain a very significant threat, present atypically and carry a high mortality. Aspergillosis remains the most common fungal infection, and infections due to Mucorales are increasing. Multidrug-resistant tuberculosis is on the increase throughout the world. Mixed infections are common and early bronchoscopy with appropriate microbiological tests, including molecular diagnostics, optimise management and reduce mortality.

CONCLUSION

Pulmonary infection remains the most frequent infectious complication in the immunocompromised host. These complex infections are often mixed, have atypical presentations and can be due to multidrug-resistant organisms. Multidisciplinary involvement in specialist centres with appropriate diagnostics, treatment and infection control improves outcome. There is a desperate need for new antimicrobial agents active against Gram-negative pathogens.

Opportunistic pulmonary infections in solid organ transplant recipients

BACKGROUND

Opportunistic pulmonary infections (OPI) represent common life-threatening complications after solid organ transplantation. Our objective was to describe pulmonary infections caused by opportunistic pathogens in solid-organ transplant patients.

METHODS

We analyzed all adult solid organ recipients (liver, heart, kidney, and pancreas) between July 2003 and June 2010, reporting all episodes of pulmonary opportunistic infection.

RESULTS

During the study period, 1656 solid organ transplants were performed and 188 opportunistic infections were diagnosed in 163 patients (incidence 10%). In 40 cases, the site of infection was the lung (21%) with 57.5% occurring between the first and sixth month posttransplantation. The most frequently isolated microorganism was Aspergillus spp (n = 25, 63%), followed by Pneumocystis jirovecii (n = 6 cs, 15%). Twenty-five patients with an opportunistic pulmonary infections died during the follow-up including, 16 related to the infection (40%). The causative organism responsible for the highest mortality was Aspergillus spp (n = 12; 48%). Twenty-one patients with an opportunistic nonrespiratory infection died, five of them related to it (4%). Opportunistic pulmonary infection was associated with an increased mortality rate (P < .001). There was a trend toward a higher mortality among patients who developed OPI during the first 6 months after transplantation.

CONCLUSIONS

Opportunistic pulmonary infections after solid organ transplantation are not infrequent. The period of risk for developing this infectious complications goes beyond the first 6 months posttransplantation. Mortality due to these infections was high in comparison to that of opportunistic nonrespiratory infections. It is important to keep a high index of suspicion for infectious complications during all posttransplant periods, as this is the first step toward a rapid diagnosis and adequate treatment.