COVID-19 in patients with liver disease and liver transplant: clinical implications, prevention, and management

The coronavirus disease 2019 (COVID-19) pandemic has had enormous implications for the care of patients with chronic liver disease (CLD), cirrhosis, and liver transplant (LT). Clinical outcomes of COVID-19 vary in patients with CLD and cirrhosis compared to healthy controls, and in patients with LT compared to patients without LT. Several special considerations apply to the approach to vaccination and treatment in patients with CLD and LT. The practice of liver transplantation has also been heavily impacted by the pandemic, including persistent reductions in living donor LT and increases in LT for an indication of alcohol-related liver disease. Recent medical society guidelines strive to standardize severe acute respiratory syndrome coronavirus 2 testing in donors and recipients and the approach to transplantation after recovered from COVID-19 infection, but certain controversies remain.

Visceral adiposity in cirrhosis: Association with disease severity and impact of liver transplantation

BACKGROUND

Changes in adipose tissue distribution in liver cirrhosis are poorly characterized and may affect clinical outcomes.

METHODS

Adult liver transplant (LT) January 2008-August 2017 recipients with abdominal MRI within 6 months pre-LT were retrospectively assessed. Visceral adipose tissue, subcutaneous adipose tissue, and skeletal muscle area (cm2) were determined at L3. Visceral-to-subcutaneous adipose tissue ratio (VSR) was used to define relative adipose distribution, stratified by sex. Correlation was tested with Pearson. Body composition measures were compared by Child-Turcotte-Pugh (CTP) class, before and after LT, and evaluated as predictors of clinical outcomes.

RESULTS

A total of 318 patients were studied. Mean age was 56 years, 33.64% were female, and 47.80% had CTP C cirrhosis. CTP C was associated with a 0.42-point increase in VSR compared with CTP A (95% CI = 0.13-0.71, p < 0.01), adjusting for age, sex, diabetes, and HCC. Among the 79 (24.84%) patients with repeat MRI 1-2 years after LT, VSR significantly improved from before LT (1.31 vs. 0.95, p < 0.01). In adjusted analysis, CTP C was associated with a 0.86-point decrease in post-LT VSR compared with pre-LT VSR (95% CI = -1.27 to -0.44, p < 0.01). Body mass index poorly correlated with VSR before and after LT. Elevated pre-LT VSR trended toward an association with a 7.17-point decrease in pre-LT glomerular filtration rate (95% CI = -14.35 to -0.02, p = 0.05), adjusting for CTP C, age, sex, diabetes, hypertension, pre-LT sarcopenia, and hepatocellular carcinoma. Elevated pre-LT VSR did not affect 3-year post-LT mortality (log-rank p = 0.24).

CONCLUSIONS

Poorly represented by body mass index, visceral adiposity is increased in cirrhosis and is associated with CTP class. However, this adipose redistribution may be modifiable by LT.

The role of gastrointestinal pathogen PCR testing in liver transplant recipients hospitalized with diarrhea

BACKGROUND

Diarrhea is a common symptom among liver transplant (LT) recipients and can result in significant morbidity. The utility of PCR-based multiplex gastrointestinal (GI) pathogen panels in this population is unknown.

METHODS

We assessed incidence, predictors, and outcomes of GI PCR positivity among inpatients who underwent stool pathogen testing with the FilmArray multiplex GI PCR panel at our institution within 1 year following LT from April 2015 to December 2019.

RESULTS

112 patients were identified. 14 (12.5%) had a positive PCR for any pathogen. Escherichia coli (n = 9) and Norovirus (n = 5) were the most common pathogens detected. Recipients with a positive PCR were significantly further from LT (median 74.5 vs 15.5 days, p < 0.01) and tested earlier during hospitalization (median 1.0 vs 9.0 days, p < 0.01). C. difficile was positive in 20.0% of patients with a positive PCR and 11.4% with a negative PCR. CMV viremia was observed in 11.6% of patients, all in the negative PCR group. Following a positive PCR, patients were more likely to have a change in antimicrobial regimen (71.4% vs 28.6%, p = 0.02), a shorter length of stay (median 7.5 vs. 17.5 days, p < 0.01), and a trend toward lower rates of readmission and colonoscopy within 30 days.

CONCLUSIONS

In hospitalized LT recipients with diarrhea, GI PCR pathogen identification was associated with the use of targeted antimicrobial therapy and a shorter length of stay. GI PCR testing should be considered early during admission and later in the post-LT period. This article is protected by copyright. All rights reserved.

Relationship Between Body Composition and Death in Patients with COVID-19 Differs Based on the Presence of Gastrointestinal Symptoms

BACKGROUND

Patients with SARS-CoV-2 who present with gastrointestinal symptoms have a milder clinical course than those who do not. Risk factors for severe COVID-19 disease include increased adiposity and sarcopenia.

AIMS

To determine whether body composition risk factors are associated with worse outcomes among patients with gastrointestinal symptoms.

METHODS

This was a retrospective study of hospitalized patients with COVID-19 who underwent abdominal CT scan for clinical indications. Abdominal body composition measures including skeletal muscle index (SMI), intramuscular adipose tissue index (IMATI), visceral adipose tissue index (VATI), subcutaneous adipose tissue index (SATI), visceral-to-subcutaneous adipose tissue ratio (VAT/SAT ratio), and liver and spleen attenuation were collected. The association between body composition measurements and 30-day mortality was evaluated in patients with and without gastrointestinal symptoms at the time of positive SARS-CoV-2 test.

RESULTS

Abdominal CT scans of 190 patients with COVID-19 were evaluated. Gastrointestinal symptoms including nausea, vomiting, diarrhea, or abdominal pain were present in 117 (62%). Among patients without gastrointestinal symptoms, those who died had greater IMATI (p = 0.049), less SMI (p = 0.010), and a trend toward a greater VAT/SAT ratio. Among patients with gastrointestinal symptoms, those who died had significantly greater IMATI (p = 0.025) but no differences in other measures.

CONCLUSIONS

Among patients with COVID-19, those without gastrointestinal symptoms showed the expected associations between mortality and low SMI, high IMATI, and trend toward higher VAT/SAT ratio, but those with gastrointestinal symptoms did not. Future studies should explore the mechanisms for the altered disease course in patients with COVID-19 who present with gastrointestinal symptoms.

Lack of Effect of Gluten Challenge on Fecal Microbiome in Patients With Celiac Disease and Non-Celiac Gluten Sensitivity

INTRODUCTION

Celiac disease (CD) may be associated with gut microbial dysbiosis. Whether discrete gluten exposure in subjects with well-controlled disease on a gluten-free diet impacts the gut microbiome is unknown and may have implications for understanding disease activity and symptoms. We conducted a prospective study to evaluate the impact of gluten exposure on the gut microbiome in patients with CD and nonceliac gluten sensitivity (NCGS).

METHODS

Subjects with CD (n = 9) and NCGS (n = 8) previously on a gluten-free diet were administered a 14-day gluten challenge (5 g of gluten per day) and compared with controls (n = 8) on a usual gluten-containing diet. Stool was collected for fecal microbiome analysis using 16S rRNA gene and metagenomic sequencing before, during, and after the gluten challenge. Symptoms were assessed using 2 validated clinical scales.

RESULTS

Among subjects with CD and NCGS, there were no significant fecal microbial changes in response to gluten challenge. Gut microbiome composition differed among controls, subjects with CD, and subjects with NCGS at baseline, and these differences persisted despite gluten exposure. Gastrointestinal and general health symptoms reported by subjects with CD and NCGS were worst in the middle of gluten challenge and lessened by its end, with no consistent associations with gut microbiome composition.

DISCUSSION

Pre-existing fecal microbiome diversity was unaffected by gluten challenge in adult subjects with CD and NCGS. These findings suggest that current microbiome status is unrelated to current disease activity and disease severity.

Oral Microbiome Alterations and SARS-CoV-2 Saliva Viral Load in Patients with COVID-19

Bacterial-viral interactions in saliva have been associated with morbidity and mortality for respiratory viruses such as influenza and SARS-CoV. However, such transkingdom relationships during SARS-CoV-2 infection are currently unknown. Here, we aimed to elucidate the relationship between saliva microbiota and SARS-CoV-2 in a cohort of newly hospitalized COVID-19 patients and controls. We used 16S rRNA sequencing to compare microbiome diversity and taxonomic composition between COVID-19 patients (n = 53) and controls (n = 59) and based on saliva SARS-CoV-2 viral load as measured using reverse transcription PCR (RT-PCR). The saliva microbiome did not differ markedly between COVID-19 patients and controls. However, we identified significant differential abundance of numerous taxa based on saliva SARS-CoV-2 viral load, including multiple species within Streptococcus and Prevotella. IMPORTANCE Alterations to the saliva microbiome based on SARS-CoV-2 viral load indicate potential biologically relevant bacterial-viral relationships which may affect clinical outcomes in COVID-19 disease.

Body Mass Index and Risk for Intubation or Death in SARS-CoV-2 Infection : A Retrospective Cohort Study

BACKGROUND

Obesity is a risk factor for pneumonia and acute respiratory distress syndrome.

OBJECTIVE

To determine whether obesity is associated with intubation or death, inflammation, cardiac injury, or fibrinolysis in coronavirus disease 2019 (COVID-19).

DESIGN

Retrospective cohort study.

SETTING

A quaternary academic medical center and community hospital in New York City.

PARTICIPANTS

2466 adults hospitalized with laboratory-confirmed severe acute respiratory syndrome coronavirus 2 infection over a 45-day period with at least 47 days of in-hospital observation.

MEASUREMENTS

Body mass index (BMI), admission biomarkers of inflammation (C-reactive protein [CRP] level and erythrocyte sedimentation rate [ESR]), cardiac injury (troponin level), and fibrinolysis (D-dimer level). The primary end point was a composite of intubation or death in time-to-event analysis.

RESULTS

Over a median hospital length of stay of 7 days (interquartile range, 3 to 14 days), 533 patients (22%) were intubated, 627 (25%) died, and 59 (2%) remained hospitalized. Compared with overweight patients, patients with obesity had higher risk for intubation or death, with the highest risk among those with class 3 obesity (hazard ratio, 1.6 [95% CI, 1.1 to 2.1]). This association was primarily observed among patients younger than 65 years and not in older patients (P for interaction by age = 0.042). Body mass index was not associated with admission levels of biomarkers of inflammation, cardiac injury, or fibrinolysis.

LIMITATIONS

Body mass index was missing for 28% of patients. The primary analyses were conducted with multiple imputation for missing BMI. Upper bounding factor analysis suggested that the results are robust to possible selection bias.

CONCLUSION

Obesity is associated with increased risk for intubation or death from COVID-19 in adults younger than 65 years, but not in adults aged 65 years or older.

PRIMARY FUNDING SOURCE

National Institutes of Health.

Alterations to the Esophageal Microbiome Associated with Progression from Barrett's Esophagus to Esophageal Adenocarcinoma

BACKGROUND

The incidence of esophageal adenocarcinoma has risen dramatically over the past half century, and the underlying reasons are incompletely understood. Broad shifts to the upper gastrointestinal microbiome may be partly responsible. The goal of this study was to describe alterations in the esophageal microbiome that occur with progression from Barrett's esophagus to esophageal adenocarcinoma.

METHODS

A case-control study was performed of patients with and without Barrett's esophagus who were scheduled to undergo upper endoscopy. Demographic, clinical, and dietary intake data were collected, and esophageal brushings were collected during the endoscopy. 16S rRNA gene sequencing was performed to characterize the microbiome.

RESULTS

A total of 45 patients were enrolled and included in the analyses [16 controls; 14 Barrett's esophagus without dysplasia (NDBE); 6 low-grade dysplasia (LGD); 5 high-grade dysplasia (HGD); and 4 esophageal adenocarcinoma]. There was no difference in alpha diversity between non-Barrett's esophagus and Barrett's esophagus, but there was evidence of decreased diversity in patients with esophageal adenocarcinoma as assessed by Simpson index. There was an apparent shift in composition at the transition from LGD to HGD, and patients with HGD and esophageal adenocarcinoma had decreased Firmicutes and increased Proteobacteria. In addition, patients with HGD or esophageal adenocarcinoma had increased Enterobacteriaceae and Akkermansia muciniphila and reduced Veillonella. In the study population, patients taking proton pump inhibitors had increased Streptococcus and decreased Gram-negative bacteria overall.

CONCLUSIONS

Shifts in the Barrett's esophagus-associated microbiome were observed in patients with HGD and esophageal adenocarcinoma, with increases in certain potentially pathogenic bacteria.

IMPACT

The microbiome may play a role in esophageal carcinogenesis.

Increasing Dietary Fiber Intake Is Associated with a Distinct Esophageal Microbiome

Introduction

There is increasing evidence that the microbiome contributes to esophageal disease. Diet, especially fiber and fat intake, is a known potent modifier of the colonic microbiome, but its impact on the esophageal microbiome is not well described. We hypothesized that dietary fiber and fat intake would be associated with a distinct esophageal microbiome.

Methods

We collected esophageal samples from 47 ambulatory patients scheduled to undergo endoscopy who completed a validated food frequency questionnaire quantifying dietary fiber and fat intake. Using 16S high-throughput sequencing, we determined composition of the esophageal microbiome and predicted functional capacity of microbiota based on fiber and fat intake.

Results

Among all samples, the most abundant phyla were Firmicutes (54.0%), Proteobacteria (19.0%), Bacteroidetes (17.0%), Actinobacteria (5.2%), and Fusobacteria (4.3%). Increasing fiber intake was significantly associated with increasing relative abundance of Firmicutes (p = 0.04) and decreasing relative abundance of Gram-negative bacteria overall (p = 0.03). Low fiber intake was associated with increased relative abundance of several Gram-negative bacteria, including Prevotella, Neisseria, and Eikenella. Several predicted metabolic pathways differed between highest and lowest quartile of fiber intake. Fat intake was associated with altered relative abundance of few taxa, with no alterations at the phylum level and no changes in microbiome functional composition.

Conclusions

Dietary fiber, but not fat, intake was associated with a distinct esophageal microbiome. Diet should be considered an important modifier of the esophageal microbiome in future studies. Studies are also needed to elucidate how the effects of dietary fiber on the esophageal microbiome may contribute to esophageal disease.

Stool PCR for Gastrointestinal Pathogens in Patients With and Without Immune-Mediated Intestinal Diseases

BACKGROUND

Patients with celiac disease and inflammatory bowel disease, two immune-mediated luminal conditions, have higher rates of certain infections than healthy counterparts. The prevalence of many gastrointestinal infections in these patients, however, is unknown.

AIMS

Using a novel clinical stool pathogen PCR test, we investigated the hypothesis that patients with celiac disease/inflammatory bowel disease had different distributions of diarrheal pathogens than other patients.

METHODS

We performed a retrospective cohort study of outpatients who underwent stool pathogen testing with the FilmArray Gastrointestinal PCR Panel (BioFire Diagnostics, Salt Lake City, UT) at our institution from January 1 to December 31, 2015. Rates of pathogens were measured in patients with or without celiac disease/inflammatory bowel disease.

RESULTS

Of 955 patients, 337 had positive test for any pathogen, with 465 bacterial, parasitic, or viral pathogens identified. One hundred and twenty-seven patients (13.3%) had celiac disease or inflammatory bowel disease, of which 29/127 (22.8%) had a positive test, compared to 308/828 other patients (37.2%) (p = 0.002). Patients with celiac disease/inflammatory bowel disease had significantly fewer viruses (1.6 vs. 8.1% of patients; p = 0.008) and parasites (0 vs. 3.3%; p = 0.039), with nonsignificant trend toward fewer bacteria (21.3 vs. 29.2%; p = 0.063). Escherichia coli species were most common in both populations.

CONCLUSIONS

Stool PCR identified numerous pathogens in patients with or without celiac disease/inflammatory bowel disease. Patients with celiac disease/inflammatory bowel disease were significantly less likely to have any pathogen identified, and had significantly fewer viruses and parasites. In this population, knowledge of common pathogens can guide diagnostic evaluation and offer opportunities for treatment.

Risk of Clostridium difficile Infection in Patients With Celiac Disease: A Population-Based Study

OBJECTIVES

Patients with celiac disease are at increased risk for infections such as tuberculosis, influenza, and pneumococcal pneumonia. However, little is known about the incidence of Clostridium difficile infection (CDI) in patients with celiac disease.

METHODS

We identified patients with celiac disease based on intestinal biopsies submitted to all pathology departments in Sweden over a 39-year period (from July 1969 through February 2008). We compared risk of CDI (based on stratified Cox proportional hazards models) among patients with celiac disease vs. without celiac disease (controls) matched by age, sex, and calendar period.

RESULTS

We identified 28,339 patients with celiac disease and 141,588 controls; neither group had a history of CDI. The incidence of CDI was 56/100,000 person-years among patients with celiac disease and 26/100,000 person-years among controls, yielding an overall hazard ratio (HR) of 2.01 (95% confidence interval (CI), 1.64-2.47; P<0.0001). The risk of CDI was highest in the first 12 months after diagnosis of celiac disease (HR, 5.20; 95% CI, 2.81-9.62; P<0.0001), but remained high, compared to that of controls, 1-5 years after diagnosis (HR, 1.85; 95% CI, 1.22-2.81; P=0.004). Among 493 patients with CDI, antibiotic data were available for 251; there were no significant differences in prior exposures to antibiotics between patients with celiac disease and controls.

CONCLUSIONS

In a large population-based cohort study, patients with celiac disease had significantly higher incidence of CDI than controls. This finding is consistent with prior findings of higher rates of other infections in patients with celiac disease, and suggests the possibility of altered gut immunity and/or microbial composition in patients with celiac disease.

Pseudohypoaldosteronism type 1 due to novel variants of SCNN1B gene

Autosomal recessive pseudohypoaldosteronism type 1 (PHA1) is a rare disorder characterized by sodium wasting, failure to thrive, hyperkalemia, hypovolemia and metabolic acidosis. It is due to mutations in the amiloride-sensitive epithelial sodium channel (ENaC) and is characterized by diminished response to aldosterone. Patients may present with life-threatening hyperkalemia, which must be recognized and appropriately treated. A 32-year-old female was referred to the National Institutes of Health (NIH) for evaluation of hyperkalemia and muscle pain. Her condition started in the second week of life, when she was brought to an outside hospital lethargic and unresponsive. At that time, she was hypovolemic, hyperkalemic and acidotic, and was eventually treated with sodium bicarbonate and potassium chelation. At the time of the presentation to the NIH, her laboratory evaluation revealed serum potassium 5.1 mmol/l (reference range: 3.4–5.1 mmol/l), aldosterone 2800 ng/dl (reference range: ≤21 ng/dl) and plasma renin activity 90 ng/ml/h (reference range: 0.6–4.3 ng/ml per h). Diagnosis of PHA1 was suspected. Sequencing of the SCNN1B gene, which codes for ENaC, revealed that the patient is a compound heterozygote for two novel variants (c.1288delC and c.1466+1 G>A), confirming the suspected diagnosis of PHA1. In conclusion, we report a patient with novel variants of the SCNN1B gene causing PHA1 with persistent, symptomatic hyperkalemia.

Variable Use of Model for End-Stage Liver Disease Exception Points in Patients With Neuroendocrine Tumors Metastatic to the Liver and Its Impact on Patient Outcomes

BACKGROUND

The role of liver transplantation in management of patients with metastatic neuroendocrine tumors (NETs) is controversial. Because many such patients have low waitlist priority, centers may apply for model for end-stage liver disease (MELD) exception points to increase likelihood of receiving a liver transplant. No formal criteria exist for application or receipt of exception points for this indication. Few studies have assessed waitlist and posttransplantation outcomes in patients with metastatic NETs, and none examined the impact of exception points.

METHODS

We analyzed all adult patients waitlisted for liver transplantation for metastatic NETs between February 27, 2002, and June 4, 2014, and fit a multivariable model to evaluate the association between exception point status and posttransplantation outcomes.

RESULTS

There was variable use of MELD exception points across the United Network for Organ Sharing regions. Patients with an approved MELD exception were nearly twice as likely to be transplanted as those without exceptions (70.8% vs 39.1%, P < 0.001), and half as likely to be removed for death or clinical deterioration (9.2% vs 18.2%, P = 0.046). In multivariable models, posttransplantation survival was not associated with receipt of exception points, whereas risk of posttransplant mortality increased significantly with elevated serum total bilirubin level at transplantation. The 3-year posttransplant patient survival was 78% in transplant recipients with metastatic NETs whose total bilirubin level at transplantation was 1.3 mg/dL or less, compared to 36% in those with total bilirubin greater than 1.3 mg/dL.

CONCLUSIONS

Serum total bilirubin may serve as a predictor of poor posttransplant survival in patients with metastatic NETs and could help risk-stratify patients applying for MELD exception points.

Racial and ethnic disparities in access to and utilization of living donor liver transplants

Living donor liver transplantation (LDLT) is a comparable alternative to deceased donor liver transplantation and can mitigate the risk of dying while waiting for transplant. Although evidence exists of decreased utilization of living donor kidney transplants among racial minorities, little is known about access to LDLT among racial/ethnic minorities. We used Organ Procurement and Transplantation Network/United Network for Organ Sharing data from February 27, 2002 to June 4, 2014 from all adult liver transplant recipients at LDLT-capable transplant centers to evaluate differential utilization of LDLTs based on race/ethnicity. We then used data from 2 major urban transplant centers to analyze donor inquiries and donor rule-outs based on racial/ethnic determination. Nationally, of 35,401 total liver transplant recipients performed at a LDLT-performing transplant center, 2171 (6.1%) received a LDLT. In multivariate generalized estimating equation models, racial/ethnic minorities were significantly less likely to receive LDLTs when compared to white patients. For cholestatic liver disease, the odds ratios of receiving LDLT based on racial/ethnic group for African American, Hispanic, and Asian patients compared to white patients were 0.35 (95% CI, 0.20-0.60), 0.58 (95% CI, 0.34-0.99), and 0.11 (95% CI, 0.02-0.55), respectively. For noncholestatic liver disease, the odds ratios by racial/ethnic group were 0.53 (95% CI, 0.40-0.71), 0.78 (95% CI, 0.64-0.94), and 0.45 (95% CI, 0.33-0.60) respectively. Transplant center-specific data demonstrated that African American patients received fewer per-patient donation inquiries than white patients, whereas fewer African American potential donors were ruled out for obesity. In conclusion, racial/ethnic minorities receive a disproportionately low percentage of LDLTs, due in part to fewer initial inquiries by potential donors. This represents a major inequality in access to a vital health care resource and demands outreach to both patients and potential donors.