Noninfectious Pulmonary Complications of Liver, Heart, and Kidney Transplantation: An Update

Very-late-onset interstitial pneumonia suspected to be related to liver transplantation more than 10 years ago

Pulmonary complications after liver transplantation are common in the postoperative period, becoming less frequent in the subsequent months, and rare after 1 year. However, we encountered two cases of very-late-onset interstitial pneumonia suspected to be related to liver transplantation after 14 and 15 years. Both patients presented with non-specific interstitial pneumonia patterns, which significantly improved with corticosteroid therapy. Physicians should be aware of such complications and monitor them after liver transplantation.

Neutrophil extracellular traps predict postoperative pulmonary complications in paediatric patients undergoing parental liver transplantation

BACKGROUND

Parental liver transplantation (PLT) improves long-term survival rates in paediatric hepatic failure patients; however, the mechanism of PLT-induced postoperative pulmonary complications (PPCs) is unclear.

METHODS

A total of 133 paediatric patients undergoing PLT were included. Serum levels of NET components, including circulating free DNA (cfDNA), DNA-histone complex, and myeloperoxidase (MPO)-DNA complex, were detected. The occurrence of PPCs post-PLT, prolonged intensive care unit (ICU) stay and death within one year were recorded as the primary and secondary outcomes.

RESULTS

The overall rate of PPCs in the hospital was 47.4%. High levels of serum cfDNA, DNA-histone complexes and MPO-DNA complexes were associated with an increased risk of PPCs (for cfDNA, OR 2.24; for DNA-histone complex, OR 1.64; and for MPO-DNA, OR 1.94), prolonged ICU stay (OR 1.98, 4.26 and 3.69, respectively), and death within one year (OR 1.53, 2.65 and 1.85, respectively). The area under the curve of NET components for the prediction of PPCs was 0.843 for cfDNA, 0.813 for DNA-histone complexes, and 0.906 for MPO-DNA complexes. During the one-year follow-up, the death rate was higher in patients with PPCs than in patients without PPCs (14.3% vs. 2.9%, P = 0.001).

CONCLUSIONS

High serum levels of NET components are associated with an increased incidence of PPCs and death within one year in paediatric patients undergoing PLT. Serum levels of NET components serve as a biomarker for post-PLT PPCs and a prognostic indicator.

Risk factor for lung infection in recipients after liver transplantation: A meta-analysis

Lung infection (LI) often occurs in patients with liver transplantation (LT). This meta-analysis was conducted to determine the risk factors associated with LI after LT. We retrieved relevant research published as of February 2020 from eight electronic databases. The studies were reviewed against the inclusion and exclusion criteria. The Z test was used to determine the combined odds ratio (OR) or the standardized mean difference (SMD) of the risk factors. We used the OR and its corresponding 95% confidence interval (CI) or the SMD and its corresponding 95% CI to identify significant differences in risk factors. A total of nine studies were included, comprising a total of 1624 recipients. Six risk factors associated with LI were identified after LT: Model for end-stage liver disease score (MELD score) (SMD = 0.40), Child-Pugh class C (OR = 3.00), intensive care unit (ICU) hospital stay (SMD = 1.35), mechanical ventilation (SMD = 1.03), bilirubin (SMD = 0.39), and atelectasis (OR = 7.28). Although certain risk factors have been identified as important factors for LI after LT, which may provide a basis for clinical prevention, a well-designed prospective study should be conducted to validate the findings of this study.

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

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

The Incidence and Risk Factors of Low Oxygenation After Orthotropic Liver Transplantation

Background

This study was designed to observe incidence and risk factors of low oxygenation after orthotropic liver transplantation (OLT).

Material/Methods

We retrospectively evaluated all adult patients who underwent living-donor OLT between January 1, 2017 and December 31, 2017. Postoperative low oxygenation was defined as PaO₂/FiO₂ <300 mmHg within 24 hours after surgery. Early acute kidney injury (AKI) after OLT was also defined when AKI was happened with 24 hours after operative.

Results

A total of 301 patients, aged 50.35±10.29 years were enrolled. Of these patients, 100 patients (33.2%) suffered postoperative low oxygenation (PaO₂/FiO₂=251.80±35.84). Compared with the normal oxygenation group, body mass index (BMI) (24.48±3.53 versus 23.1±3.27 kg/m², P=0.001), preoperative hemoglobin (115.79±29.27 versus 111.52±29.80 g/L, P=0.033), preoperative MELD (22.25±6.54 versus 20.24±5.74, P=0.008), and intraoperative urinary volume (1.25 [0.76, 1.89] versus 2.04 [1.49, 3.68] mL/kg/h, P=0.003) were higher in low oxygenation group. There were more cases of earlier AKIs that occurred after OLT in low oxygenation patients than that in normal group (47% versus 23.4%, P<0.001). Logistic analysis showed that the preoperative BMI (hazard ration [HR]=1.107, [1.010, 1.212], P=0.029) and early AKI after OLT (HR=2.115, [1.161, 3.855], P=0.014) were independent risk factors for postoperative low oxygenation.

Conclusions

The incidence of postoperative low oxygenation after liver transplantation in adults was 33.2%. BMI and early AKI after OLT were correlated with postoperative hypoxemia.

Pulmonary Complications After Solid Organ Transplantation: An Autopsy Perspective

Pulmonary complications following solid organ transplantation are common and often infectious in nature. Articles describing noninfectious pulmonary complications overwhelmingly rely on clinical and radiographic data. There are a limited number of studies with companion histology delineating the clinical diagnoses of pulmonary complications. This contrasts with blood and bone marrow transplantations. Using a retrospective cohort approach, the current study aimed to assess antemortem and postmortem pulmonary findings in solid organ transplantation recipients. Medical records and autopsy materials from 92 solid organ transplantation recipients were reviewed. Pulmonary complications were identified in 70 patients (76%). For patients with pulmonary complications at autopsy the mean survival posttransplantation was 3.48 years as compared to 7.29 years for patients without pulmonary complications at autopsy (P = .01). Twenty-eight infectious complications (fungal pneumonia, n = 20; cytomegalovirus pneumonia, n = 7; bacterial pneumonia, n = 1) and 113 noninfectious pulmonary complications were identified. The most common noninfectious findings were diffuse alveolar damage (n = 32), organizing pneumonia (n = 31), and pulmonary thromboemboli (n = 26). Disseminated infections and respiratory failure were the most common immediate causes of death (n = 24 and n = 23, respectively). Most noninfectious complications were not diagnosed antemortem.