Comparison of techniques for volumetric analysis of the future liver remnant: implications for major hepatic resections.

OBJECTIVE: The purpose of this work was to compare measured and estimated volumetry prior to liver resection. METHODS: Data for consecutive patients submitted to major liver resection for colorectal liver metastases at two centres during 2004-2012 were reviewed. All patients underwent volumetric analysis to define the measured total liver volume (mTLV) and measured future liver remnant ratio (mR(FLR)). The estimated total liver volume (eTLV) standardized to body surface area and estimated future liver remnant ratio (eR(FLR)) were calculated. Descriptive statistics were generated and compared. A difference between mR(FLR) and eR(FLR) of ±5% was considered clinically relevant. RESULTS: Data for a total of 116 patients were included. All patients underwent major resection and 51% underwent portal vein embolization. The mean difference between mTLV and eTLV was 157 ml (P < 0.0001), whereas the mean difference between mR(FLR) and eR(FLR) was -1.7% (P = 0.013). By linear regression, eTLV was only moderately predictive of mTLV (R(2) = 0.35). The distribution of differences between mR(FLR) and eR(FLR) demonstrated that the formula over- or underestimated mR(FLR) by ≥5% in 31.9% of patients. CONCLUSIONS: Measured and estimated volumetry yielded differences in the FLR of ≥5% in almost one-third of patients, potentially affecting clinical decision making. Estimated volumetry should be used cautiously and cannot be recommended for general use.

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.

Renal tubular injury in hyperbilirubinemia: Bile cast nephropathy.

The toxic renal accumulation of bile pigment sparked clinical intrigue almost a century ago. More recently, however, the identification of bile casts within renal tubules in patients with liver dysfunction has been largely overlooked. We have reviewed the literature, including natural history, pathophysiology, and potential treatment of bile cast nephropathy (BCN). We report two cases of acute kidney injury (AKI) associated with acute-on-chronic liver failure in which prolonged hyperbilirubinemia and bile cast identification on renal biopsy evoked the diagnosis of BCN.