Using machine learning to predict antibody response to SARS-CoV-2 vaccination in solid organ transplant recipients: the multicentre ORCHESTRA cohort.

OBJECTIVES: The study aim was to assess predictors of negative antibody response (AbR) in solid organ transplant (SOT) recipients after the first booster of SARS-CoV-2 vaccination. METHODS: Solid organ transplant recipients receiving SARS-CoV-2 vaccination were prospectively enrolled (March 2021-January 2022) at six hospitals in Italy and Spain. AbR was assessed at first dose (t0), second dose (t1), 3 ± 1 month (t2), and 1 month after third dose (t3). Negative AbR at t3 was defined as an anti-receptor binding domain titre <45 BAU/mL. Machine learning models were developed to predict the individual risk of negative (vs. positive) AbR using age, type of transplant, time between transplant and vaccination, immunosuppressive drugs, type of vaccine, and graft function as covariates, subsequently assessed using a validation cohort. RESULTS: Overall, 1615 SOT recipients (1072 [66.3%] males; mean age±standard deviation [SD], 57.85 ± 13.77) were enrolled, and 1211 received three vaccination doses. Negative AbR rate decreased from 93.66% (886/946) to 21.90% (202/923) from t0 to t3. Univariate analysis showed that older patients (mean age, 60.21 ± 11.51 vs. 58.11 ± 13.08), anti-metabolites (57.9% vs. 35.1%), steroids (52.9% vs. 38.5%), recent transplantation (<3 years) (17.8% vs. 2.3%), and kidney, heart, or lung compared with liver transplantation (25%, 31.8%, 30.4% vs. 5.5%) had a higher likelihood of negative AbR. Machine learning (ML) algorithms showing best prediction performance were logistic regression (precision-recall curve-PRAUC mean 0.37 [95%CI 0.36-0.39]) and k-Nearest Neighbours (PRAUC 0.36 [0.35-0.37]). DISCUSSION: Almost a quarter of SOT recipients showed negative AbR after first booster dosage. Unfortunately, clinical information cannot efficiently predict negative AbR even with ML algorithms.

A Case Report of Tolvaptan Therapy for ADPKD Patients With COVID-19. The Need for Appropriate Counselling for Temporary Drug Discontinuation.

BACKGROUND: Patients with autosomal dominant polycystic kidney disease (ADPKD) may require specific therapy with vasopressin receptor antagonists to slow the progression of renal disease. Because of its mechanism of action, the most common side effects are polyuria, nocturia, and polydipsia. Elevations of liver enzyme levels can also occur during treatment with Tolvaptan. Temporary drug withdrawal may be indicated if the patient is unable to hydrate adequately or if there are concomitant causes of dehydration, including major infectious events. During the Coronavirus Disease 2019 (COVID-19) pandemic, this should be considered in the management of patients on Tolvaptan therapy. CASE REPORT: We present the clinical case of a 51-year-old male with severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2) infection and ADPKD receiving Tolvaptan therapy with particular reference to the medical management of the patient during the infectious event. The patient was instructed to discontinue promptly Tolvaptan as soon as symptoms appeared. He was treated with forced hydration and symptomatic therapy. Nevertheless, a transient elevation of liver enzyme levels was detected. The timely discontinuation of Tolvaptan therapy avoided the risk of potential hepatotoxicity in a condition of known susceptibility. CONCLUSION: Tolvaptan therapy of patients with ADPKD is safe even during SARS-CoV-2 infection. There is need for appropriate and prompt patient counseling to avoid potentially adverse side effects.

Efficacy of corticosteroid treatment for hospitalized patients with severe COVID-19: a multicentre study.

OBJECTIVE: To assess the efficacy of corticosteroids in patients with coronavirus disease 2019 (COVID-19). METHODS: A multicentre observational study was performed from 22 February through 30 June 2020. We included consecutive adult patients with severe COVID-19, defined as respiratory rate ≥30 breath per minute, oxygen saturation ≤93% on ambient air or arterial partial pressure of oxygen to fraction of inspired oxygen ≤300 mm Hg. We excluded patients being treated with other immunomodulant drugs, receiving low-dose corticosteroids and receiving corticosteroids 72 hours after admission. The primary endpoint was 30-day mortality from hospital admission. The main exposure variable was corticosteroid therapy at a dose of ≥0.5 mg/kg of prednisone equivalents. It was introduced as binomial covariate in a logistic regression model for the primary endpoint and inverse probability of treatment weighting using the propensity score. RESULTS: Of 1717 patients with COVID-19 evaluated, 513 were included in the study, and of these, 170 (33%) were treated with corticosteroids. During hospitalization, 166 patients (34%) met the criteria of the primary outcome (60/170, 35% in the corticosteroid group and 106/343, 31% in the noncorticosteroid group). At multivariable analysis corticosteroid treatment was not associated with lower 30-day mortality rate (adjusted odds ratio, 0.59; 95% confidence interval (CI), 0.20-1.74; p 0.33). After inverse probability of treatment weighting, corticosteroids were not associated with lower 30-day mortality (average treatment effect, 0.05; 95% CI, -0.02 to 0.09; p 0.12). However, subgroup analysis revealed that in patients with PO2/FiO2 < 200 mm Hg at admission (135 patients, 52 (38%) treated with corticosteroids), corticosteroid treatment was associated with a lower risk of 30-day mortality (23/52, 44% vs. 45/83, 54%; adjusted odds ratio, 0.20; 95% CI, 0.04-0.90; p 0.036). CONCLUSIONS: The effect of corticosteroid treatment on mortality might be limited to critically ill COVID-19 patients.