COVID-19 in Solid Organ Transplantation: A Matched Retrospective Cohort Study and Evaluation of Immunosuppression Management

Use of chronic medications and risk of death due to COVID-19 in hospitalised patients

OBJECTIVES

To evaluate the potential association between chronic exposure to medication and death related to COVID-19.

METHODS

This is a retrospective cross-sectional study that included all patients hospitalised due to COVID-19 from 11 March to 4 June 2020 in our centre. Chronic patient medication was classified by the Anatomical Therapeutic Chemical (ATC) classification; demographic and clinical data were analysed. Multivariate logistic regression models were used to estimate the adjusted odds ratios (aOR) of death for each drug exposure; each aOR represents an independent model adjusted by clinical factors related to COVID-19 mortality.

RESULTS

The study included 978 patients with a mean (SD) age of 64.5 (17.7) years who were predominantly male (531, 54.3%). Of all 978 patients, 182 (18.61%) died during the follow-up of the study. The most common Charlson Comorbidity Index (CCI) was 0, 4.2% were smokers, 16.7% were obese, 47.4% had hypertension, and 19.4% were diabetic. Most patients (70.8%) were prescribed at least one treatment, 32.5% used >5 treatments, and 8.6% >10. Our data suggest that COVID-19 hospitalised patients taking trimethoprim and analogues, leukotriene receptor antagonists, calcineurin inhibitors, aldosterone antagonists, selective immunosuppressants, propulsives, insulins and analogues, and benzodiazepine derivatives have a higher risk of death.

CONCLUSIONS

This study investigated the association between chronic exposure to drugs and the risk of death in COVID-19 patients. Our results have shed some light on the impact of chronic drug exposure on the risk of severe COVID-19; however, further research is needed to increase the understanding about its relevance.

Comprehensive immune profiling of SARS-CoV-2 infected kidney transplant patients

Introduction

The immune responses of kidney transplant recipients against SARS-CoV-2 remains under studied.

Methods

In this prospective pilot study, we performed comprehensive immune profiling using cellular, proteomic, and serologic assays on a cohort of 9 kidney transplant recipients and 12 non-transplant individuals diagnosed with COVID-19.

Results

Our data show that in addition to having reduced SARS-CoV-2 specific antibody levels, kidney transplant recipients exhibited significant cellular differences including a decrease in naïve-but increase in effector T cells, a high number of CD28+ CD4 effector memory T cells, and increased CD8 T memory stem cells compared with non-transplant patients. Furthermore, transplant patients had lower concentrations of serum cytokine MIP-1β as well as a less diverse T cell receptor repertoire.

Conclusion

Overall, our results show that compared to non-transplant patients, kidney transplant recipients with SARS-CoV-2 infection exhibit an immunophenotype that is reminiscent of the immune signature observed in patients with severe COVID-19.

Understanding the Elevated Lethality of COVID-19 in Liver Transplant Recipients: Does Immunosuppression Management Matter? Results from a Brazilian Multicentric Historical Cohort

BACKGROUND

Infections by SARS-CoV-2 in liver transplant recipients (LT) patients are of particular concern, notably due to perceived added risks related to immunosuppression and comorbidity burden. Current literature on this topic often relies on small, non-standardized, and geographically limited studies. This manuscript describes COVID-19 presentations and causes for elevated mortality in a large cohort of LT recipients.

METHODS

This study was designed as a multicentric historical cohort, including LT recipient patients with COVID-19 in 25 study centers, with the primary endpoint being COVID-related death. We also collected demographic, clinical, and laboratory data regarding presentation and disease progression.

RESULTS

Two hundred and thirty-four cases were included. The study population was predominantly male and White and had a median age of 60 years. The median time from transplantation was 2.6 years (IQR 1-6). Most patients had at least one comorbidity (189, 80.8%). Patient age (P = .04), dyspnea (P < .001), intensive care unit admission (P < .001), and mechanical ventilation (P < .001) were associated with increased mortality. Modifications of immunosuppressive therapy (P < .001), specifically the suspension of tacrolimus, maintained significance in multivariable analysis.

CONCLUSIONS

Attention to risk factors and the individualization of patient care, especially regarding immunosuppression management, is crucial for delivering more precise interventions to these individuals.

Vaccines and therapeutics for immunocompromised patients with COVID-19

The COVID-19 pandemic has disproportionately impacted immunocompromised patients. This diverse group is at increased risk for impaired vaccine responses, progression to severe disease, prolonged hospitalizations and deaths. At particular risk are people with deficiencies in lymphocyte number or function such as transplant recipients and those with hematologic malignancies. Such patients' immune responses to vaccination and infection are frequently impaired leaving them more vulnerable to prolonged high viral loads and severe complications of COVID-19. Those in turn, have implications for disease progression and persistence, development of immune escape variants and transmission of infection. Data to guide vaccination and treatment approaches in immunocompromised people are generally lacking and extrapolated from other populations. The large clinical trials leading to authorisation and approval of SARS-CoV-2 vaccines and therapeutics included very few immunocompromised participants. While experience is accumulating, studies focused on the special circumstances of immunocompromised patients are needed to inform prevention and treatment approaches.

SARS-CoV-2 induced liver injury: Incidence, risk factors, impact on COVID-19 severity and prognosis in different population groups

Liver is unlikely the key organ driving mortality in coronavirus disease 2019 (COVID-19) however, liver function tests (LFTs) abnormalities are widely observed mostly in moderate and severe cases. According to this review, the overall prevalence of abnormal LFTs in COVID-19 patients ranges from 2.5% to 96.8% worldwide. The geographical variability in the prevalence of underlying diseases is the determinant for the observed discrepancies between East and West. Multifactorial mechanisms are implicated in COVID-19-induced liver injury. Among them, hypercytokinemia with "bystander hepatitis", cytokine storm syndrome with subsequent oxidative stress and endotheliopathy, hypercoagulable state and immuno-thromboinflammation are the most determinant mechanisms leading to tissue injury. Liver hypoxia may also contribute under specific conditions, while direct hepatocyte injury is an emerging mechanism. Except for initially observed severe acute respiratory distress syndrome corona virus-2 (SARS-CoV-2) tropism for cholangiocytes, more recent cumulative data show SARS-CoV-2 virions within hepatocytes and sinusoidal endothelial cells using electron microscopy (EM). The best evidence for hepatocellular invasion by the virus is the identification of replicating SARS-CoV-2 RNA, S protein RNA and viral nucleocapsid protein within hepatocytes using in-situ hybridization and immunostaining with observed intrahepatic presence of SARS-CoV-2 by EM and by in-situ hybridization. New data mostly derived from imaging findings indicate possible long-term sequelae for the liver months after recovery, suggesting a post-COVID-19 persistent live injury.

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.

COVID-19: Has the Liver Been Spared?

The liver is a secondary and often collateral target of COVID-19 disease but can lead to important consequences. COVID-19 might directly cause a high number of complications in patients with pre-existing chronic liver disease, increasing their risk of hepatic decompensation. Moreover, it also determines indirect consequences in the management of patients with liver disease, especially in those suffering from decompensated cirrhosis and HCC, as well as in the execution of their follow-up and the availability of all therapeutic possibilities. Liver imaging in COVID-19 patients proved to be highly nonspecific, but it can still be useful for identifying the complications that derive from the infection. Moreover, the recent implementation of telemedicine constitutes a possible solution to both the physical distancing and the re-organizational difficulties arising from the pandemic. The present review aims to encompass the currently hypothesized pathophysiological mechanisms of liver injury in patients with COVID-19 mediated by both the direct invasion of the virus and its indirect effects and analyze the consequence of the pandemic in patients with chronic liver disease and liver tumors, with particular regard to the management strategies that have been implemented to face this worldwide emergency and that can be further improved.

Prognostic factors for mortality, intensive care unit and hospital admission due to SARS-CoV-2: a systematic review and meta-analysis of cohort studies in Europe

BACKGROUND

As mortality from coronavirus disease 2019 (COVID-19) is strongly age-dependent, we aimed to identify population subgroups at an elevated risk for adverse outcomes from COVID-19 using age-/gender-adjusted data from European cohort studies with the aim to identify populations that could potentially benefit from booster vaccinations.

METHODS

We performed a systematic literature review and meta-analysis to investigate the role of underlying medical conditions as prognostic factors for adverse outcomes due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including death, hospitalisation, intensive care unit (ICU) admission and mechanical ventilation within three separate settings (community, hospital and ICU). Cohort studies that reported at least age and gender-adjusted data from Europe were identified through a search of peer-reviewed articles published until 11 June 2021 in Ovid Medline and Embase. Results are presented as odds ratios with 95% confidence intervals and absolute risk differences in deaths per 1000 COVID-19 patients.

FINDINGS

We included 88 cohort studies with age-/gender-adjusted data from 6 653 207 SARS-CoV-2 patients from Europe. Hospital-based mortality was associated with high and moderate certainty evidence for solid organ tumours, diabetes mellitus, renal disease, arrhythmia, ischemic heart disease, liver disease and obesity, while a higher risk, albeit with low certainty, was noted for chronic obstructive pulmonary disease and heart failure. Community-based mortality was associated with a history of heart failure, stroke, diabetes and end-stage renal disease. Evidence of high/moderate certainty revealed a strong association between hospitalisation for COVID-19 and solid organ transplant recipients, sleep apnoea, diabetes, stroke and liver disease.

INTERPRETATION

The results confirmed the strong association between specific prognostic factors and mortality and hospital admission. Prioritisation of booster vaccinations and the implementation of nonpharmaceutical protective measures for these populations may contribute to a reduction in COVID-19 mortality, ICU and hospital admissions.

COVID-19 infection in liver transplant recipients: Clinical features and outcomes from a Canadian multicentre cohort

BACKGROUND: Prior studies have assessed risk factors and clinical outcomes in liver transplant (LT) recipients infected with COVID-19 globally; however, there is a paucity of Canadian data. Our multicentre study aims to examine the characteristics and clinical outcomes of LT patients with COVID-19 infection in Canada. METHODS: Adult LT recipients with reverse transcription-polymerase chain reaction (RT-PCR) confirmed COVID-19, from Canadian tertiary care centres between March 2020 and June 2021 were included. RESULTS: A total of 49 patients with a history of LT and COVID-19 infection were identified. Twenty-nine patients (59%) were male, median time from LT was 66 months (IQR 1-128), and median age was 59 years (IQR 52-65). At COVID-19 diagnosis, the median alanine transaminase (ALT) was 37 U/L (IQR 21-41), aspartate aminotransferase (AST) U/L was 34 (IQR 20-37), alkaline phosphatase (ALP) U/L was 156 (IQR 88-156), total bilirubin was 11 μmol/L (IQR 7-14), and international normalized ratio (INR) was 1.1 (IQR 1.0-1.1). The majority of patients (86%) were on tacrolimus (monotherapy or combined with mycophenolate mofetil); median tacrolimus level at COVID-19 diagnosis was 5.3 μg/L (IQR 4.0-8.1). Immunosuppression was modified in eight (16%) patients post-infection. Eighteen patients (37%) required hospitalization, and three (6%) required intensive care unit (ICU) admission and mechanical ventilation. Four patients (8%) died from complications related to COVID-19 infection. On univariate analysis, neither age, sex, comorbidities, nor duration post-transplant were associated with risk of hospitalization or ICU admission. CONCLUSIONS: LT recipients with COVID-19 have high rates of hospitalization but fortunately have low rates of ICU admission and mortality in this national registry.

Can the COVID-19 Pandemic Improve the Management of Solid Organ Transplant Recipients?

Increased mortality due to SARS-CoV-2 infection was observed among solid organ transplant patients. During the pandemic, in order to prevent and treat COVID-19 infections in this context, several innovative procedures and therapies were initiated within a short period of time. A large number of these innovations can be applied and expanded to improve the management of non-COVID-19 infectious diseases in solid organ transplant patients and in the case of a future pandemic. In this vein, the present paper reviews and discusses medical care system adaptation, modification of immunosuppression, adjuvant innovative therapies, the role of laboratory expertise, and the prevention of infections as examples of such innovations.

Clinical outcome in solid organ transplant recipients affected by COVID-19 compared to general population: a systematic review and meta-analysis

BACKGROUND

A significant increased risk of complications and mortality in immunocompromised patients affected by COVID-19 has been described. However, the impact of COVID-19 in solid organ transplant (SOT) recipients is an issue still under debate, due to conflicting evidence that has emerged from different observational studies.

OBJECTIVES

We performed a systematic review with a meta-analysis to assess the clinical outcome in SOT recipients with COVID-19 compared with the general population.

DATA SOURCES

PubMed-MEDLINE and Scopus were independently searched until 13 October 2021.

STUDY ELIGIBILITY CRITERIA

Prospective or retrospective observational studies comparing clinical outcome in SOT recipients versus general populations affected by COVID-19 were included. The primary endpoint was 30-day mortality.

PARTICIPANTS

Participants were patients with confirmed COVID-19.

INTERVENTIONS

Interventions reviewed were SOTs.

METHODS

The quality of the included studies was independently assessed with the Risk of Bias in Non-randomized Studies of Interventions tool for observational studies. The meta-analysis was performed by pooling ORs retrieved from studies providing adjustment for confounders using a random-effects model with the inverse variance method. Multiple subgroups and sensitivity analyses were conducted to investigate the source of heterogeneity.

RESULTS

A total of 3501 articles were screened, and 31 observational studies (N = 590 375; 5759 SOT recipients vs. 584 616 general population) were included in the meta-analyses. No difference in 30-day mortality rate was found in the primary analysis, including studies providing adjustment for confounders (N = 17; 3752 SOT recipients vs. 159 745 general population; OR: 1.13; 95% CI, 0.94-1.35; I2 = 33.9%). No evidence of publication bias was reported. A higher risk of intensive care unit admission (OR: 1.56; 95% CI, 1.03-2.63) and occurrence of acute kidney injury (OR: 2.50; 95% CI, 1.81-3.45) was found in SOT recipients.

CONCLUSIONS

No increased risk in mortality was found in SOT recipients affected by COVID-19 compared with the general population when adjusted for demographic and clinical features and COVID-19 severity.

Immune responses to SARS-CoV-2 in dialysis and kidney transplantation

Despite progressive improvements in the management of patients with coronavirus disease 2019 (COVID-19), individuals with end-stage kidney disease (ESKD) are still at high risk of infection-related complications. Although the risk of infection in these patients is comparable to that of the general population, their lower rate of response to vaccination is a matter of concern. When prevention strategies fail, infection is often severe. Comorbidities affecting patients on maintenance dialysis and kidney transplant recipients clearly account for the increased risk of severe COVID-19, while the role of uremia and chronic immunosuppression is less clear. Immune monitoring studies have identified differences in the innate and adaptive immune response against the virus that could contribute to the increased disease severity. In particular, individuals on dialysis show signs of T cell exhaustion that may impair antiviral response. Similar to kidney transplant recipients, antibody production in these patients occurs, but with delayed kinetics compared with the general population, leaving them more exposed to viral expansion during the early phases of infection. Overall, unique features of the immune response during COVID-19 in individuals with ESKD may occur with severe comorbidities affecting these individuals in explaining their poor outcomes.

A Comprehensive Comparison of Clinical Presentation and Outcomes of Kidney Transplant Recipients with COVID-19 during Wave 1 versus Wave 2 at a Tertiary Care Center, India

Data comparing the clinical spectrum of COVID-19 in kidney transplant recipients (KTRs) during the first and second waves of the pandemic in India is limited. Our single-center retrospective study compared the clinical profile, mortality, and associated risk factors in KTRs with COVID-19 during the 1st wave (1^st February 2020 to 31^st January 2021) and the second wave (1^st March-31^st August 2021). 156 KTRs with PCR confirmed SARS-CoV-2 infection treated at a tertiary care hospital in New Delhi during the 1st and the second waves were analyzed. The demographics and baseline transplant characteristics of the patients diagnosed during both waves were comparable. Patients in the second wave reported less frequent hospitalization, though the intensive care unit (ICU) and ventilator requirements were similar. Strategies to modify immunosuppressants such as discontinuation of antinucleoside drugs with or without change in calcineurin inhibitors and the use of steroids were similar during both waves. Overall patient mortality was 27.5%. The demographics and baseline characteristics of survivors and nonsurvivors were comparable. A higher percentage of nonsurvivors presented with breathing difficulty, low SpO₂, and altered sensorium. Both wave risk factors for mortality included older age, severe disease, ICU/ventilator requirements, acute kidney injury (AKI) needing dialysis, Chest Computerized Tomographic (CT) scan abnormalities, and higher levels of inflammatory markers particularly D-dimer and interleukin-6 levels. Conclusions. KTRs in both COVID-19 waves had similar demographics and baseline characteristics, while fewer patients during the second wave required hospitalization. The D-dimer and IL-6 levels are directly correlated with mortality.

Impact of solid organ transplant status on outcomes of hospitalized patients with COVID-19 infection

Background

The COVID‐19 pandemic has caused significant morbidity and mortality in solid organ transplant (SOT) recipients. However, it remains unclear whether the risk factor for SOT patients is the immunosuppression inherent to transplantation versus patient comorbidities.

Methods

We reviewed outcomes in a cohort of SOT (n = 129) and non‐SOT (NSOT) patients (n = 708) admitted to the University of California, Los Angeles for COVID‐19 infection. Data analyses utilized multivariate logistic regression to evaluate the impact of patient demographics, comorbidities, and transplant status on outcomes. SOT patients were analyzed by kidney SOT (KSOT) versus nonkidney SOT (NKSOT) groups.

Results

SOT and NSOT patients with COVID‐19 infection differed in terms of patient age, ethnicity, and comorbidities. NKSOT patients were the most likely to experience death, with a mortality rate of 16.2% compared with 1.8% for KSOT and 8.3% for NSOT patients (p = .013). Multivariable analysis of hospitalized patients revealed that patient age (odds ratio [OR] 2.79, p = .001) and neurologic condition (OR 2.66, p < .001) were significantly associated with mortality. Analysis of ICU patients revealed a 2.98‐fold increased odds of death in NKSOT compared with NSOT patients (p = .013).

Conclusions

This study demonstrates the importance of transplant status in predicting adverse clinical outcomes in patients hospitalized or admitted to the ICU with COVID‐19, especially for NKSOT patients. Transplant status and comorbidities, including age, could be used to risk stratify patients with COVID‐19. This data suggests that immunosuppression contributes to COVID‐19 disease severity and mortality and may have implications for managing immunosuppression, especially for critically ill patients admitted to the ICU.

Induction immunosuppression and outcome in kidney transplant recipients with early COVID-19 after transplantation

COVID-19 in kidney transplants has a high risk of complications and mortality, especially in older recipients diagnosed during the early period after transplantation. Management of immunosuppression has been challenging during the pandemic. We investigated the impact of induction immunosuppression, either basiliximab or thymoglobulin, on the clinical evolution of kidney transplants developing COVID-19 during the early period after transplantation. Kidney transplant recipients with less than 6 months with a functioning graft diagnosed of COVID-19 from the initial pandemic outbreak (March 2020) until July 31st, 2021 from different Spanish centers participating in a nationwide registry. A total of 127 patients from 17 Spanish centers developed COVID-19 during the first 6 months after transplantation, 73 (57.5%) received basiliximab and 54 (42.5%) thymoglobulin. Demographics were not different between groups but patients receiving thymoglobulin were more sensitized (cPRA of 32.7±40.8% vs. 5.6±18.5%) and were more frequently re-transplants (30% vs. 4%). Recipients older than 65 years treated with thymoglobulin showed the highest rate of acute respiratory distress syndrome (64.7% vs. 37.1% for older recipients receiving thymoglobulin and basiliximab [p&lt;0.05], and 23.7% and 18.9% for young recipients receiving basiliximab and thymoglobulin [p&gt;0.05]) and the poorest survival (mortality rate of 64.7% and 42.9% for older recipients treated with thymoglobulin and basiliximab, respectively [p&lt;0.05], and 8.1% and 10.5% for young recipients treated with thymoglobulin and basiliximab [p&gt;0.05]). Older recipients treated with thymoglobulin showed the poorest survival in the Cox's regression model adjusted for comorbidities. Thus, thymoglobulin should be used with caution in older recipients during the present pandemic era.

Post vaccination analysis of anti-spike antibody responses in kidney transplant recipients with and without COVID-19 infection in a tertiary care center, India

Background

To investigate the anti-spike antibody response to vaccination in Kidney transplant recipients (KTRs) previously infected with SARS-CoV-2 as compared to KTRs with no history of COVID-19 from India.

Methods

SARS-CoV-2 spike immunoglobulin (Ig) G antibody response was measured in 105 post COVID-19 KTRs with PCR confirmed SARS-CoV-2 infection who received either no vaccination (cohort 1), single (cohort 2) or two doses (cohort 3) of vaccine and compared to 103 two-dose vaccinated COVID-19 naïve KTRs with no history of COVID-19 (cohort 4).

Results

Out of 103 COVID-19 naïve two-dose vaccinated KTRs, less than 50% became seropositive with anti-spike antibody titres &gt; 50AU/mL subsequent to complete vaccination, the seroconversion rate being comparable in subjects receiving CovishieldTM versus CovaxinTM vaccines. However, the seropositive KTRs vaccinated with CovishieldTM had higher anti-spike antibody titres as compared to those who received CovaxinTM. We observed higher anti-SARS-CoV-2 spike antibody levels in post COVID-19 KTRs after 1 dose of vaccine as compared with COVID-19 naïve two-dose vaccinated KTRs. Importantly, the second dose in post COVID-19 KTRs did not significantly increase anti-spike antibody levels compared with the single dose recipients.

Conclusions

Our data presents that in KTRs with previous SARS-CoV-2 infection a single dose of vaccine (CovishieldTM) may be effective in mounting optimal immune response. In contrast, COVID-19 naïve two-dose vaccinated KTRs respond poorly (&lt;50%) to current recommendation of a two-dose regimen in India.

Outcomes of SOT Recipients With COVID-19 in Different Eras of COVID-19 Therapeutics

BACKGROUND

Few reports have focused on newer coronavirus disease 2019 (COVID-19) therapies (remdesivir, dexamethasone, and convalescent plasma) in solid organ transplant recipients; concerns had been raised regarding possible adverse impact on allograft function or secondary infections.

METHODS

We studied 77 solid organ transplant inpatients with COVID-19 during 2 therapeutic eras (Era 1: March-May 2020, 21 patients; and Era 2: June-November 2020, 56 patients) and 52 solid organ transplant outpatients.

RESULTS

In Era 1, no patients received remdesivir or dexamethasone, and 4 of 21 (19.4%) received convalescent plasma, whereas in Era 2, remdesivir (24/56, 42.9%), dexamethasone (24/56, 42.9%), and convalescent plasma (40/56, 71.4%) were commonly used. Mortality was low across both eras, 4 of 77 (5.6%), and rejection occurred in only 2 of 77 (2.8%) inpatients; infections were similar in hypoxemic patients with or without dexamethasone. Preexisting graft dysfunction was associated with greater need for hospitalization, higher severity score, and lower survival. Acute kidney injury was present in 37.3% of inpatients; renal function improved more rapidly in patients who received remdesivir and convalescent plasma. Post-COVID-19 renal and liver function were comparable between eras, out to 90 d.

CONCLUSIONS

Newer COVID-19 therapies did not appear to have a deleterious effect on allograft function, and infectious complications were comparable.

Coronavirus Disease 2019 (COVID-19) in Solid Organ Transplant Recipients: A Case-Control Study

Background

It is unclear whether solid organ transplant (SOT) patients have more severe coronavirus disease 2019 (COVID-19) and worse outcome than the general population.

Material/Methods

We conducted a case-control study on 32 SOT recipients and 84 non-SOT controls matched for age and sex admitted for confirmed COVID-19. The primary endpoint was in-hospital all-cause mortality rate. Secondary endpoints included severe acute respiratory distress syndrome (ARDS), use of high-flow oxygen therapy, and length of hospital stay.

Results

The median (IQR) Charlson comorbidity index (CCI) at admission was significantly higher in SOT recipients (6 (3–8) vs 3 (2–4); P<0.01). Fever was less frequent in SOT recipients (78% vs 94%, P=0.01). SOT recipients had a higher median SaO2/FiO2 at admission (452 [443–462] vs 443 [419–452], P<0.01) and reached the worst SaO2/FiO2 value later during hospitalization 15 (10–21) vs 11 (9–14) days, P=0.01). Both groups had a similar severe ARDS rate during hospitalization (33% vs 28%) (p=0.59). There were no significant differences during hospitalization in terms of highest level of respiratory support needed, or length of hospital stay: 8.5 (5.5–21) vs 11.5 (6.5–16.5) days; P=0.34) in SOT recipients when compared to controls. In-hospital all-cause mortality rates were significantly higher in SOT recipients (21.9% vs 4.7%, P<0.01; OR 1.08; 95% CI 0.10–10.98), but among patients who died, median CCI was similar between groups (8 [6–8] vs 7 [6–8]).

Conclusions

In our experience, hospitalized SOT recipients for COVID-19 had higher in-hospital mortality compared to non-SOT patients, probably due to the greater number of underlying comorbidities, and not directly related to chronic immunosuppression.

The Impact of SARS-CoV-2 Infection, and Application of Immunosuppressive Agents in Kidney Transplant Recipients Suffering from COVID-19

In December 2019, the COVID-19 pandemic began to ravage the world quickly, causing unprecedented losses in human life and the economy. A statistical study revealed that the proportion of solid organ transplant (SOT) recipients with severe symptoms and deaths after being infected by SARS-CoV-2 is considerably higher than that of non-SOT recipients, and the prognosis is relatively poor. In addition, the clinical manifestation of SOT recipients suffering from COVID-19 is different from that of general COVID-19 patients. Acute kidney injury (AKI) is a common complication in COVID-19 patients, and it is likely more common among SOT recipients infected with SARS-CoV-2. Clinical experts consider that SOT recipients have long-term treatment with immunosuppressants, and the comorbidities are driven by a high rate of severe symptoms and mortality. Orthotopic kidney allograft transplantation is an effective treatment for patients suffering from end-stage kidney disease/kidney failure through which they can easily extend their life. Indeed, kidney transplant recipients have suffered significant damage during this pandemic. To effectively reduce the severity of symptoms and mortality of kidney transplant recipients suffering from COVID-19, precise application of various drugs, particularly immunosuppressants, is necessary. Therefore, herein, we will collate the current clinical experience of treating COVID-19 infection in kidney transplant recipients and discuss the adjustment of patients using immunosuppressive agents in the face of COVID-19.

Immunosuppressant Management in Renal Transplant Patients with COVID-19

The coronavirus disease 2019 (COVID-19) pandemic poses a special risk for both immunosuppressed patients, especially transplant recipients. Although the knowledge about this infection is growing, many uncertainties remain, particularly regarding the kidney. Kidney transplant recipients (KDRs) should be considered immunocompromised hosts since a potential risk for infection, comorbidity, and immunosuppression exposure exists. Additionally, the management of immunosuppressive agents in KDRs remains challenging. Potential drug interactions with immunosuppressive treatment escalated the risk of unwanted side effects. In this review, we aimed to attain an augmented awareness and improved management immunosuppressant for COVID-19 KDRs.

Prospective Clinical, Virologic, and Immunologic Assessment of COVID-19 in Transplant Recipients

BACKGROUND

Several studies have described the clinical features of COVID-19 in solid-organ transplant recipients. However, many have been retrospective or limited to more severe cases (hospitalized) and have not routinely included serial virological sampling (especially in outpatients) and immunologic assessment.

METHODS

Transplant patients diagnosed with COVID-19 based on a respiratory sample PCR were prospectively followed up to 90 d. Patients provided consent for convalescent serum samples and serial nasopharyngeal swabs for SARS-CoV-2 antibody (antinucleoprotein and anti-RBD) and viral load, respectively.

RESULTS

In the 161 SOT recipients diagnosed with COVID-19, the spectrum of disease ranged from asymptomatic infection (4.3%) to hospitalization (60.6%), supplemental oxygen requirement (43.1%), mechanical ventilation (22.7%), and death (15.6%). Increasing age (OR, 1.031; 95% CI, 1.001-1.062; P = 0.046) and ≥2 comorbid conditions (OR, 3.690; 95% CI, 1.418-9.615; P = 0.007) were associated with the need for supplemental oxygen. Allograft rejection was uncommon (3.7%) despite immunosuppression modification. Antibody response at ≥14 d postsymptoms onset was present in 90% (anti-RBD) and 76.7% (anti-NP) with waning of anti-NP titers and stability of anti-RBD over time. Median duration of nasopharyngeal positivity was 10.0 d (IQR, 5.5-18.0) and shedding beyond 30 d was observed in 6.7% of patients. The development of antibody did not have an impact on viral shedding.

CONCLUSIONS

This study demonstrates the spectrum of COVID-19 illness in transplant patients. Risk factors for severe disease are identified. The majority form antibody by 2 wk with differential stability over time. Prolonged viral shedding was observed in a minority of patients. Reduction of immunosuppression was a safe strategy.

SARS-CoV-2 in Solid Organ Transplant Recipients: A Structured Review of 2020

BACKGROUND

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is challenging health systems all over the world. Particularly high-risk groups show considerable mortality rates after infection. In 2020, a huge number of case reports, case series, and consecutively various systematic reviews have been published reporting on morbidity and mortality risk connected with SARS-CoV-2 in solid organ transplant (SOT) recipients. However, this vast array of publications resulted in an increasing complexity of the field, overwhelming even for the expert reader.

METHODS

We performed a structured literature review comprising electronic databases, transplant journals, and literature from previous systematic reviews covering the entire year 2020. From 164 included articles, we identified 3451 cases of SARS-CoV-2-infected SOT recipients.

RESULTS

Infections resulted in a hospitalization rate of 84% and 24% intensive care unit admissions in the included patients. Whereas 53.6% of patients were reported to have recovered, cross-sectional overall mortality reported after coronavirus disease 2019 (COVID-19) was at 21.1%. Synoptic data concerning immunosuppressive medication attested to the reduction or withdrawal of antimetabolites (81.9%) and calcineurin inhibitors (48.9%) as a frequent adjustment. In contrast, steroids were reported to be increased in 46.8% of SOT recipients.

CONCLUSIONS

COVID-19 in SOT recipients is associated with high morbidity and mortality worldwide. Conforming with current guidelines, modifications of immunosuppressive therapies mostly comprised a reduction or withdrawal of antimetabolites and calcineurin inhibitors, while frequently maintaining or even increasing steroids. Here, we provide an accessible overview to the topic and synoptic estimates of expectable outcomes regarding in-hospital mortality of SOT recipients with COVID-19.

COVID-19 en receptores de trasplante renal: ¿qué hemos aprendido tras 18 meses de pandemia?

La infección por el SARS-CoV-2 (COVID-19) ha supuesto un importante impacto en la actividad trasplantadora en nuestro país. En su condición de paciente inmunodeprimido y con frecuentes comorbilidades, era esperable que la mortalidad y el riesgo de complicaciones asociadas a la COVID-19 en el receptor de trasplante renal (TR) fueran mayores en comparación con la población general, si bien la información al respecto en los primeros meses de la pandemia era muy limitada. Desde marzo de 2020 hemos mejorado rápidamente nuestro conocimiento acerca de la epidemiología, características clínicas y manejo de la COVID-19 post-trasplante. La presente revisión pretende recopilar la información disponible a julio de 2021 en respuesta a una serie de cuestiones relevantes: ¿cómo se manifiesta clínicamente la infección por SARS-CoV-2 en receptores de TR?, ¿cuáles son sus factores pronósticos?, ¿es más grave la COVID-19 en el contexto del TR respecto a los pacientes inmunocompetentes?, ¿de qué opciones de tratamiento antiviral disponemos actualmente para el receptor de TR?, ¿cuál es la experiencia disponible con los tratamientos inmunomoduladores? y, por último, ¿son eficaces las vacunas frente a la COVID-19 basadas en ARN mensajero en esta población?. A pesar de los avances realizados aún son varios los aspectos que debemos mejorar en nuestro abordaje de la infección por SARS-CoV-2 en el ámbito específico del TR.

The Impact of COVID-19 on Kidney Transplant Recipients in Pre-Vaccination and Delta Strain Era: A Systematic Review and Meta-Analysis

Herein, we performed a meta-analysis of published clinical outcomes of corona virus disease 2019 (COVID-19) in hospitalized kidney transplant recipients. A systematic database search was conducted between December 1, 2019 and April 20, 2020. We analyzed 48 studies comprising 3137 kidney transplant recipients with COVID-19. Fever (77%), cough (65%), dyspnea (48%), and gastrointestinal symptoms (28%) were predominant on hospital admission. The most common comorbidities were hypertension (83%), diabetes mellitus (34%), and cardiac disease (23%). The pooled prevalence of acute respiratory distress syndrome and acute kidney injury were 58% and 48%, respectively. Invasive ventilation and dialysis were required in 24% and 22% patients, respectively. In-hospital mortality rate was as high as 21%, and increased to over 50% for patients in intensive care unit (ICU) or requiring invasive ventilation. Risk of mortality in patients with acute respiratory distress syndrome (ARDS), on mechanical ventilation, and ICU admission was increased: OR = 19.59, OR = 3.80, and OR = 13.39, respectively. Mortality risk in the elderly was OR = 3.90; however, no such association was observed in terms of time since transplantation and gender. Fever, cough, dyspnea, and gastrointestinal symptoms were common on admission for COVID-19 in kidney transplant patients. Mortality was as high as 20% and increased to over 50% in patients in ICU and required invasive ventilation.

A Review of Treatment and Prevention of Coronavirus Disease 2019 among Solid Organ Transplant Recipients

Therapeutic management of solid organ transplant (SOT) recipients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of coronavirus disease 2019 (COVID-19), may challenge healthcare providers given a paucity of clinical data specific to this cohort. Herein, we summarize and review the studies that have formed the framework for current COVID-19 consensus management guidelines. Our review focuses on COVID-19 treatment options including monoclonal antibody products, antiviral agents such as remdesivir, and immunomodulatory agents such as corticosteroids, interleukin inhibitors, and kinase inhibitors. We highlight the presence or absence of clinical data of these therapeutics related to the SOT recipient with COVID-19. We also describe data surrounding COVID-19 vaccination of the SOT recipient. Understanding the extent and limitations of observational and clinical trial data for the prevention and treatment of COVID-19 specific to the SOT population is crucial for optimal management. Although minimal data exist on clinical outcomes among SOT recipients treated with varying COVID-19 therapeutics, reviewing these agents and the studies that have led to their inclusion or exclusion in clinical management of COVID-19 highlights the need for further studies of these therapeutics in SOT patients with COVID-19.

COVID-19 Severity and Mortality in Solid Organ Transplantation: Differences between Liver, Heart, and Kidney Recipients

The infection by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) can generate a wide spectrum of clinical manifestations ranging from asymptomatic to severe respiratory and systemic disease with coagulation disorder named coronavirus disease 2019 (COVID-19). Patients with comorbidities have been identified as risk groups for severe COVID-19, also having a higher death risk. Previous reports have conflicting results regarding if solid organ transplant recipients present an increased risk for COVID-19. Nevertheless, previous investigations failed to distinguish between different organs received or made a longitudinal investigation on those patients. We recruited 39 solid organ transplant recipients: 25 kidney transplant recipients, 7 heart transplant recipients, and 7 liver transplant recipients and 25 age-matched non-transplant COVID-19 patients without comorbidities (control group) and compared daily laboratory data in addition to performing survival analysis. Heart and kidney transplant recipients presented an increase in several COVID-19 severity-associated biomarkers, such as neutrophil-to-lymphocyte ratio and thrombocytopenia, in comparison to the control group and liver transplant recipients. Heart and kidney transplant recipients also presented an increase in the need for intensive care and invasive mechanical ventilation during the disease’s course. Importantly, heart and kidney transplant recipients presented a higher mortality rate in comparison to liver transplant recipients and non-transplant recipients. In our cohort, heart and kidney transplant recipients presented a difference in clinical characteristics and survival rate in comparison to liver transplant recipients. Further investigation involving immune response to SARS-CoV-2 in solid organ recipients should consider and separate patients according to the organ grafted.

COVID-19 in hospitalized lung and non-lung solid organ transplant recipients: A comparative analysis from a multicenter study

Lung transplant recipients (LTR) with coronavirus disease 2019 (COVID-19) may have higher mortality than non-lung solid organ transplant recipients (SOTR), but direct comparisons are limited. Risk factors for mortality specifically in LTR have not been explored. We performed a multicenter cohort study of adult SOTR with COVID-19 to compare mortality by 28 days between hospitalized LTR and non-lung SOTR. Multivariable logistic regression models were used to assess comorbidity-adjusted mortality among LTR vs. non-lung SOTR and to determine risk factors for death in LTR. Of 1,616 SOTR with COVID-19, 1,081 (66%) were hospitalized including 120/159 (75%) LTR and 961/1457 (66%) non-lung SOTR (p = .02). Mortality was higher among LTR compared to non-lung SOTR (24% vs. 16%, respectively, p = .032), and lung transplant was independently associated with death after adjusting for age and comorbidities (aOR 1.7, 95% CI 1.0-2.6, p = .04). Among LTR, chronic lung allograft dysfunction (aOR 3.3, 95% CI 1.0-11.3, p = .05) was the only independent risk factor for mortality and age >65 years, heart failure and obesity were not independently associated with death. Among SOTR hospitalized for COVID-19, LTR had higher mortality than non-lung SOTR. In LTR, chronic allograft dysfunction was independently associated with mortality.

Immunosuppression in solid organ transplant recipients with Covid-19: More data, but still complicated

“Outcomes of COVID‐19 in solid organ transplant (SOT) recipients: a matched cohort study” by Pereira et al found similar 28 day mortality among hospitalized SOT recipients and comorbidity matched controls, shedding light on the relationship between immunosuppression and Covid‐19 outcomes.

The Full Spectrum of COVID-19 Development and Recovery Among Kidney Transplant Recipients

BACKGROUND

Coronavirus disease 2019 (COVID-19) fatality rate is high among kidney transplant recipients. Among survivors, kidney outcomes, seroconversion, and persistence of viral shedding are unexplored.

METHODS

Single-center prospective cohort study including data from kidney transplant recipients with confirmed COVID-19 between March 20, 2020 and July 31, 2020. Outcomes were adjudicated until August 31, 2020 or the date of death.

RESULTS

There were 491 patients with COVID-19 among the 11 875 recipients in follow-up. The majority were middle aged with ≥1 comorbidities. Thirty-one percent were treated at home, and 69% required hospitalization. Among the hospitalized, 61% needed intensive care, 75% presented allograft dysfunction, and 46% needed dialysis. The overall 28-day fatality rate was 22% and among hospitalized patients it was 41%. Age (odds ratio, 3.08; 95% confidence interval, 1.86-5.09), diabetes mellitus (odds ratio, 1.69; 95% confidence interval, 1.06-2.72), and cardiac disease (odds ratio, 2.00; 95% confidence interval, 1.09-3.68) were independent factors for death. Among the 351 survivors, 19% sustained renal graft dysfunction, and there were 13 (4%) graft losses. Biopsy (n = 20) findings were diverse but decisive to guide treatment and estimate prognosis. Seroconversion was observed in 79% of the survivors and was associated with disease severity. Persistence of viral shedding was observed in 21% of the patients without detectable clinical implications.

CONCLUSIONS

This prospective cohort analysis confirms the high 28-day fatality rate of COVID-19, associated primarily with age and comorbidities. The high incidence of allograft dysfunction was associated with a wide range of specific histologic lesions and high rates of sequelae and graft loss. Seroconversion was high and the persistence of viral shedding deserves further studies.

Low seroprevalence of SARS-CoV-2 antibodies in a liver transplant cohort

Solid organ transplant recipients might be at greater risk for acquisition and mortality because of SARS‐CoV‐2. There are no data regarding SARS‐CoV‐2 seroprevalence among liver transplant (LT) recipients, and whether it is different from that of the general population or other immunosuppressed groups. We evaluated the prevalence of IgG SARS‐CoV‐2 antibodies among LT recipients to estimate the frequency of asymptomatic SARS‐CoV‐2 infection using serological assays in our outpatient clinic. We conducted a cross‐sectional analysis from 10 May to 26 October 2020 of all adult (>18 years) LT recipients that underwent a routine laboratory test for the outpatient clinic follow‐up at the Hospital Universitari Vall d’Hebron (Barcelona) in which we included serological testing for SARS‐CoV‐2. Nine out of 294 LT recipients (3.1%) tested positive for anti‐SARS‐CoV‐2 IgG antibodies. Five of them (55.5%) had suffered clinically symptomatic SARS‐CoV‐2 infection confirmed by RT‐PCR, four (44.4%) had presented compatible symptoms but without microbiological confirmation and only one patient (1/9, 11.1%) tested positive without any previous symptom. SARS‐CoV‐2 seroprevalence among LT recipients in an area highly affected by the pandemic is lower than in the general population in the same area. These results render the possibility of asymptomatic infection in LT recipients very unlikely.

Cardiac transplant recipient with COVID-19 induced acute hypoxic respiratory failure: a case report

BACKGROUND

Heart transplant recipients represent a particularly vulnerable patient population to the novel coronavirus disease 2019 (COVID-19) due to chronic immunosuppression and high rates of comorbidities. Currently, data are limited and evidence to guide management of heart transplant recipients with COVID-19 is sparse. In this case report, we provide a summary of the current literature as well as an in-depth analysis of our clinical decision-making.

CASE SUMMARY

A 67-year-old female who underwent cardiac transplantation 1 year prior was found to have acute hypoxic respiratory failure due to COVID-19. Her immunosuppressant medications were modulated with discontinuation of mycophenolate and titration of tacrolimus troughs with a goal of 6-10 ng/dL. She was administered supportive treatment including convalescent plasma, remdesivir, and dexamethasone, in addition to antibiotic treatment that resulted in resolution of her symptoms within a matter of days despite her precarious disposition.

DISCUSSION

This case demonstrates that it can be safe and efficacious to modulate immunosuppressant medications in cardiac transplant recipients in accordance with recommendations made by the International Society of Heart and Lung Transplantation. This case additionally demonstrates that aspects of the current literature regarding the management of COVID-19 can be safely extrapolated to cardiac transplant recipients. Providing supportive care with dexamethasone, remdesivir, and convalescent plasma as indicated can be beneficial in cardiac transplant recipients; although, the current literature regarding convalescent plasma and remdesivir is conflicting.

COVID-19 and the liver - Lessons learned

Liver involvement, indicated by elevated liver function test results, is common in hospitalized patients with coronavirus disease 2019 (COVID-19) and has been linked to disease severity and outcome. A dual pattern of elevated liver function tests can be observed especially in patients with severe or critical COVID-19, characterized by an increase in aminotransferases early in the course of this disease, followed by an increase in cholestasis-associated biochemistry markers at later stages. This dual pattern is associated with inflammatory response markers and poor outcome. Current notions on the mechanisms of liver injury in COVID-19 include direct cytopathic effects of the virus on hepatocytes and cholangiocytes, ischemic and hypoxic liver damage, drug-induced liver injury, activation of hepatic immune cells by excess cytokine production and exacerbation of pre-existing liver disease. Patients with obesity-related non-alcoholic fatty liver disease and, in particular, patients with cirrhosis are at high risk of liver injury and a fatal outcome from COVID-19. In contrast, individuals receiving stable immunosuppressive medication for autoimmune liver diseases or during long-term follow-up after liver transplantation do not have a higher case-to-infection ratio and have a fairly favourable outcome. The present review describes the epidemiology, characteristics and potential pathological mechanisms of COVID-19-related liver injury. Moreover, the influence of pre-existing liver disease on the susceptibility and severity of liver injury in COVID-19 are discussed.

The association between severe or death COVID-19 and solid organ transplantation: A systematic review and meta-analysis

Background

The effect of solid organ transplantation (SOT) on the severity and mortality of coronavirus disease 2019 (COVID-19) remained controversial. There is still no consensus on whether solid organ transplantation (SOT) recipients with COVID-19 are at greater risk of developing severe or fatal COVID-19. Therefore, we conducted a systematic review and meta-analysis to investigate the association between SOT, severe COVID-19 illness, and mortality.

Methods

A systemically comprehensive search in Pubmed, Embase, the Cochrane Library, Web of Science, and China National Knowledge Infrastructure was performed for relevant studies and articles. Consequently, we pooled the odds ratio (OR) from individual studies and performed heterogeneity, quality assessment and subgroup/sensitivity analysis.

Results

A total number of 15 articles with 265,839 participants were included in this study. Among the total number of participants, 1485 were SOT recipients. The meta-analysis results showed that transplant patients with COVID-19 were remarkably associated with a higher risk of intensive care unit admission than non-transplant patients (OR = 1.57, 95%CI: 1.07 to 2.31, P = 0.02). On the other hand, there were no statistically significant differences between SOT recipients and non-SOT recipients in mechanical ventilation need (OR = 1.55, 95%CI: 0.98 to 2.44, P = 0.06). In addition, we found that SOT recipients with COVID-19 had 1.40-fold increased odds of mortality than non-SOT recipients (OR = 1.40, 95%CI: 1.10 to 1.79, P = 0.007). Moreover, pooled analysis of adjusted results revealed that SOT recipients had a greater risk of mortality compared with non-SOT patients (HR = 1.54, 95%CI: 1.03 to 2.32, P = 0.037).

Limitations

The main limitations in our study are attributed to the relatively small sample size, short follow-up period, and the fact that most of the studies included were retrospective in design.

Conclusions

The results of this study indicate that SOT recipients with COVID-19 had a more significant risk of COVID-19 severity and mortality than the general population.

Outcomes of COVID-19 in hospitalized solid organ transplant recipients compared to a matched cohort of non-transplant patients at a national healthcare system in the United States

Data describing outcomes of solid organ transplant (SOT) recipients with coronavirus disease 2019 (COVID-19) are variable, and the association between SOT status and mortality remains unclear. In this study, we compare clinical outcomes of SOT recipients hospitalized with COVID-19 between March 10, and September 1, 2020, to a matched cohort of non-SOT recipients at a national healthcare system in the United States (US). From a population of 43 461 hospitalized COVID-19-positive patients, we created a coarsened exact matched cohort of 4035 patients including 128 SOT recipients and 3907 weighted matched non-SOT controls. Multiple logistic regression was used to evaluate association between SOT status and clinical outcomes. Among the 4035 patients, median age was 60 years, 61.7% were male, 21.9% were Black/African American, and 50.8% identified as Hispanic/Latino ethnicity. Patients with a history of SOT were more likely to die within the study period when compared to matched non-SOT recipients (21.9% and 14.9%, respectively; odds ratio [OR] 1.93; 95% confidence interval [CI]: 1.18-3.15). Moreover, SOT status was associated with increased odds of receiving invasive mechanical ventilation (OR [95% CI]: 2.34 [1.51-3.65]), developing acute kidney injury (OR [95% CI]: 2.41 [1.59-3.65]), and receiving vasopressor support during hospitalization (OR [95% CI]: 2.14 [1.31-3.48]).

Clinical Profile and Outcome of COVID-19 in 250 Kidney Transplant Recipients: A Multicenter Cohort Study From India

BACKGROUND

There is a scarcity of data on the consequences of coronavirus disease-19 (COVID-19) infections in kidney transplant recipients (KTRs) from emerging countries.

METHODS

Here, we present a cohort study of 13 transplant centers in India including 250 KTR (226 living and 24 deceased donors) with polymerase chain reaction-confirmed COVID-19 positivity from March 23, 2020, until September 15, 2020. We detailed demographics, immunosuppression regimen, clinical profile, treatment, and outcomes.

RESULTS

Median age of transplant recipients was 43 years, and recipients presented at a median of 3.5 years after transplant. Most common comorbidities (94%) included arterial hypertension (84%) and diabetes (32%); presenting symptoms at the time of COVID-19 included fever (88%), cough (72%), and sputum production (52%). Clinical severity ranged from asymptomatic (6%), mild (60%), and moderate (20%) to severe (14%). Strategies to modify immunosuppressants included discontinuation of antimetabolites without changes in calcineurin inhibitors and steroids (60%). Risk factors for mortality included older age; dyspnea; severe disease; obesity; allograft dysfunction before COVID-19 infection; acute kidney injury; higher levels of inflammatory markers including C-reactive protein, interleukin-6 level, and procalcitonin; chest X-ray abnormality, and intensive care unit/ventilator requirements. Overall patient mortality was 11.6% (29 of 250), 14.5% (29 of 200) in hospitalized patients, 47% (25 of 53) in intensive care unit patients, and 96.7% (29 of 30) in patients requiring ventilation. KTRs with mild COVID-19 symptoms (n = 50) were managed as outpatients to optimize the utilization of scarce resources during the COVID-19 pandemic.

CONCLUSIONS

Mortality rates in COVID-19-positive KTR appear to be higher than those in nonimmunosuppressed patients, and high mortality was noted among those requiring intensive care and those on ventilator.

Immune Responses to SARS-CoV-2 in Solid Organ Transplant Recipients

PURPOSE OF REVIEW

Coronavirus disease 2019 (COVID-19) is caused by a complex interplay between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) dynamics and host immune responses. Hosts with altered immunity, including solid organ transplant recipients, may be at increased risk of complications and death due to COVID-19. A synthesis of the available data on immune responses to SARS-CoV-2 infection is needed to inform therapeutic and preventative strategies in this special population.

RECENT FINDINGS

Few studies have directly compared immune responses to SARS-CoV-2 between transplant recipients and the general population. Like non-transplant patients, transplant recipients mount an exuberant inflammatory response following initial SARS-CoV2 infection, with IL-6 levels correlating with disease severity in some, but not all studies. Transplant recipients display anti-SARS-CoV-2 antibodies and activated B cells in a time frame and magnitude similar to non-transplant patients-limited data suggest these antibodies can be detected within 15 days of symptom onset and may be durable for several months. CD4+ and CD8+ T lymphopenia, a hallmark of COVID-19, is more profound in transplant recipients, but SARS-CoV-2-reactive T cells can be detected among patients with both mild and severe disease.

SUMMARY

The limited available data indicate that immune responses to SARS-CoV-2 are similar between transplant recipients and the general population, but no studies have been sufficiently comprehensive to understand nuances between organ types or level of immunosuppression to meaningfully inform individualized therapeutic decisions. The ongoing pandemic provides an opportunity to generate higher-quality data to support rational treatment and vaccination strategies in this population.

Kidney transplantation and COVID-19 renal and patient prognosis

Coronavirus disease 2019 (COVD-19) emerged as a pandemic in December 2019. Infection has spread quickly and renal transplant recipients receiving chronic immunosuppression have been considered a population at high risk of infection, complications and infection-related death. During this year a large amount of information from nationwide registries, multicentre and single-centre studies have been reported. The number of renal transplant patients diagnosed with COVID-19 was higher than in the general population, but the lower threshold for testing may have contributed to its better identification. Major complications such as acute kidney injury and acute respiratory distress syndrome were very frequent in renal transplant patients, with a high comorbidity burden, but further studies are needed to support that organ transplant recipients receiving chronic immunosuppression are more prone to develop these complications than the general population. Kidney transplant recipients experience a high mortality rate compared with the general population, especially during the very early post-transplant period. Despite the fact that some studies report more favourable outcomes in patients with a kidney transplant than in patients on the kidney waiting list, the higher mortality described in the very early post-transplant period would advise against performing a kidney transplant in areas where the spread of infection is high, especially in recipients >60 years of age. Management of transplant recipients has been challenging for clinicians and strategies such as less use of lymphocyte-depleting agents for new transplants or anti-metabolite withdrawal and calcineurin inhibitor reduction for transplant patients with COVID-19 are not based on high-quality evidence.

COVID-19: biologic and immunosuppressive therapy in gastroenterology and hepatology

The coronavirus disease 2019 (COVID-19) pandemic is an ongoing global health crisis causing major challenges for clinical care in patients with gastrointestinal diseases. Although triggering of anti-viral immune responses is essential for clearance of infection, some patients have severe lung inflammation and multiorgan failure due to marked immune cell dysregulation and cytokine storm syndrome. Importantly, the activation of cytotoxic follicular helper T cells and a reduction of regulatory T cells have a crucial, negative prognostic role. These findings lead to the question of whether immunosuppressive and biologic therapies for gastrointestinal diseases affect the incidence or prognosis of COVID-19 and, thus, whether they should be adjusted to prevent or affect the course of the disease. In this Review, data on the use of such therapies are discussed with a primary focus on inflammatory bowel disease, autoimmune hepatitis and liver transplantation. In particular, the roles of corticosteroids, classic immunosuppressive agents (such as thiopurines and mycophenolate mofetil), small molecules (such as Janus kinase (JAK) inhibitors), and biologic agents (such as tumour necrosis factor (TNF) blockers, vedolizumab and ustekinumab) are reviewed. Finally, the use of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines for the prevention of infection in patients with gastrointestinal diseases and concomitant immunosuppressive or biologic therapy will be discussed.