Detection and localization of calcium oxalate in kidney using synchrotron deep ultraviolet fluorescence microscopy

Renal oxalosis is a rare cause of renal failure whose diagnosis can be challenging. Synchrotron deep ultraviolet (UV) fluorescence was assayed to improve oxalosis detection on kidney biopsies spatial resolution and sensitivity compared with the Fourier transform infrared microspectroscopy gold standard. The fluorescence spectrum of synthetic mono-, di- and tri-hydrated calcium oxalate was investigated using a microspectrometer coupled to the synchrotron UV beamline DISCO, Synchrotron SOLEIL, France. The obtained spectra were used to detect oxalocalcic crystals in a case control study of 42 human kidney biopsies including 19 renal oxalosis due to primary (PHO, n = 11) and secondary hyperoxaluria (SHO, n = 8), seven samples from PHO patients who received combined kidney and liver transplants, and 16 controls. For all oxalocalcic hydrates samples, a fluorescence signal is detected at 420 nm. These spectra were used to identify standard oxalocalcic crystals in patients with PHO or SHO. They also revealed micrometric crystallites as well as non-aggregated oxalate accumulation in tubular cells. A nine-points histological score was established for the diagnosis of renal oxalosis with 100% specificity (76–100) and a 73% sensitivity (43–90). Oxalate tubular accumulation and higher histological score were correlated to lower estimated glomerular filtration rate and higher urinary oxalate over creatinine ratio.

Disparity in Access to Care Impacts Liver Transplant Mortality

This study aims to analyze how access to care influences patient mortality rates after liver transplants in adults by analyzing the relationships between insurance coverage, income, geographic location, and mortality rates post-transplantation. It was hypothesized that a sociodemographic variable, such as insurance type, geographical location, and income level would impact mortality rates post-liver transplant. Results showed that unknown insurance coverage increased the likelihood of mortality post-transplant, income level was not found to be a significant indicator, and patients living in the Northeast region of the United States were more likely to die post-liver transplant.

Race/Ethnicity Is Not Independently Associated with Risk of Adverse Waitlist Removal among Patients with HCC Exception Points

(1) Background: Since 2015, exception points have been awarded to appropriate candidates after six months of waitlist time to allow more equitable access to liver transplants regardless of hepatocellular carcinoma status. However, it remains unknown whether racial disparities in outcomes among waitlisted patients remain after the introduction of a 6-month waiting period for exception points. (2) Methods: Using the United Network for Organ Sharing database, we identified 2311 patients diagnosed with hepatocellular carcinoma listed for liver transplant who received exception points from 2015 to 2019. The outcome of interest was waitlist survival defined as the composite outcome of death or removal for clinical deterioration. Competing risk analysis was used to identify factors associated with death or removal for clinical deterioration. The final model adjusted for age, sex, race/ethnicity, blood type, diabetes, obesity, laboratory MELD score, tumor size, AFP, locoregional therapies, UNOS region, and college education. (3) Results: No difference was found in the risk of adverse waitlist removal among ethnic/racial groups.

Correlation of Liver Stiffness Measurements with AST to Platelet Ratio Index (APRI) and Fibrosis-4 (FIB-4) Scores in Pediatric Patients with Hepatitis B or Liver Transplantation

Background and Objective: Current standard for assessing liver fibrosis is biopsy. However, its invasive nature, cost, and limited sampling are problematic for many patients. Fibroscan is a technology that utilizes transient elastography (TE) to measure liver stiffness (LSM) quickly and non-invasively. TE is a novel method in children and has shown to be a measure of fibrosis. Biomarkers for hepatic fibrosis include the APRI and FIB-4 scores, which are not well-studied in children. Our goal is to correlate APRI and FIB-4 with LSM in children who have hepatitis B (hep B) or have received liver transplants (LT). Methods: LSM scores of 26 children with hep B and 41 children with LT were retrieved from a research database at Riley Hospital for Children. We then obtained laboratory results closest to the date (+/- 1 year) of their TE. Those results were used to determine APRI and FIB-4 scores. Spearman correlation (rs) was determined between LSM/APRI, LSM/FIB-4, and APRI/FIB-4 in each disease. Results: Table 1. Spearman Correlations for LSM/APRI, LSM/FIB-4, and APRI/FIB-4 in Hep B and LT Disease Comparison Spearman Correlation (rs) Hep B LSM APRI 0.321 LSM FIB-4 0.376 APRI FIB-4 0.731* LT LSM APRI 0.303 LSM FIB-4 0.526* APRI FIB-4 0.632* *p < 0.05 Conclusion and Potential Impact: The moderate correlation of LSM with FIB-4 in LT shows potential for future clinical use, but the correlations of LSM with APRI in both conditions and the correlation of LSM with FIB-4 in Hep B are weaker. APRI and FIB-4 are strongly correlated in these children. However, additional studies with larger sample sizes should be completed. Because patients with LT and chronic hep B regularly need longitudinal evaluation, finding non-invasive tools are important to ensure compliance and ease.

P-L17 Post-liver transplant inferior vena cava stenosis in a large volume UK centre

Background Inferior vena cava stenosis (IVCS) is a rare complication of liver transplantation with a reported incidence rate of 3%. Limited clinical consensus exists on the management of IVCS. We report the management and outcomes of patients with IVCS at our transplant centre. Methods Relevant data were collected from adult patients who underwent liver transplantation at our centre between October 2014 and August 2020. These included demographics, investigation and management details with regards to IVCS. Values presented as % of total and median with interquartile range (IQR). Results A total of 636 liver transplants were performed during the study period, of which 48 (7.6%) patients were investigated for possible IVCS. Of those, 14 (2.2% of total) were found to have IVCS, 85.7% (n = 12) were female. Only 2/14 were re-transplants and pre-transplant portal vein thrombus was present in 3 cases (21.4%). 10 livers (71.4%) were DBD donors. Normothermic machine perfusion was used in 4/14 patients. All 14 recipients found to have IVCS had had an implantation using a modified piggyback cavocavostomy technique. The IVCS was identified at a median of 25.5 days (19.7-30.8 days) following transplantation within the suprahepatic IVC in 92.9% (n = 13). Hemi-azygos collateralisation was seen in 4 cases (28.6%). 8 of the 14 recipients underwent intervention for IVCS, 6 patients were managed with balloon venoplasty, 1 patient required an IVC stent and 1 was managed surgically. Six of the recipients with IVCS died, 4 of whom had an intervention for their stenosis and 3 of these were within 90 days of their transplant. Pressures measured at the anastomotic stricture were higher in those who succumbed (median of 21 Vs 12.5 mmHg; p=.017). Conclusions At our centre, cava-replacement technique was not associated with IVCS. Patients with more significant strictures (as evidenced by higher pressures at the anastomotic stenosis) may have an increased mortality risk.