Faculty Bibliography

Primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) are uncommon liver diseases of unknown etiology. Reported clustering of PBC cases may be due to environmental factors. Individuals with PBC have a high prevalence of thyroid disease and thyroid disease is reportedly more prevalent near Superfund toxic waste sites (SFS). The objective of this study was to examine the prevalence and potential clustering of individuals with PBC and PSC near SFS. De-identified clinical and demographic data were used to determine the observed prevalence for each New York City zip code (n = 174) and borough (n = 5) of patients with PBC (PBC-OLT) or PSC (PSC-OLT) who were listed for liver transplantation. The expected prevalence was calculated using Organ Procurement and Transfer Network (OPTN) and U.S. Census data. Both PBC-OLT patients and patients not listed for liver transplantation (PBC-MSSM) were included in the cluster analysis. Prevalence ratios of PBC-OLT and PSC-OLT cases were compared for each zip code and for each borough with regard to the proximity or density of SFS, respectively. SaTScan software was used to identify clusters of PBC-OLT cases and PBC-MSSM cases. Prevalence ratio of PBC-OLT, not PSC-OLT, was significantly higher in zip codes containing or adjacent to SFS (1.225 vs. 0.670, respectively, P = .025). The borough of Staten Island had the highest prevalence ratio of PBC-OLT cases and density of SFS. Significant clusters of both PBC-OLT and PBC-MSSM were identified surrounding SFS. In conclusion, toxin exposure may be a risk factor influencing the clustering of PBC cases

OBJECTIVES: Fatigue, which may have a significant impact on quality of life, is the most common reported symptom in primary biliary cirrhosis (PBC). Multiple instruments to quantify fatigue and quality of life in liver disease have been validated, but have not been broadly applied to U.S. PBC patients. This study examines the extent of fatigue and its effect on quality of life in U.S. PBC patients. METHODS: Seventy patients with PBC were administered two validated questionnaires about quality of life (the Mayo version of the NIDDK-QA) and fatigue (the Fisk Fatigue Impact Score) and a proposed physical measure of fatigue in PBC (the grip strength test) on the day of routine physician visit. Nonparametric methods were employed. RESULTS: The fatigue and quality of life domain scores (physical functioning, liver symptoms, health satisfaction, Karnofsky index) discriminated between patients with and without self-reported fatigue (p < 0.05), as opposed to the grip strength results. Fatigue and quality of life domains correlated strongly with each other (r between 0.33 and 0.74, p</= 0.006) and not with the grip strength results. Neither quality of life nor fatigue scores correlated with age. CONCLUSIONS: The correlation between fatigue and quality of life scores suggests fatigue has an impact on quality of life in U.S. primary biliary cirrhosis patients. However, our fatigue scores suggest U.S. PBC patients have less fatigue than non-U.S. PBC patients. The grip strength is an insensitive measure of fatigue in U.S. PBC patients

Glycyrrhizin (GL) is used in Japan for the treatment of chronic hepatitis C. Following intravenous administration, GL is eliminated mainly by excretion into bile. Hepatocyte uptake of GL is a carrier-mediated process with characteristics resembling the organic anion transporting polypeptides (OATPs, solute carrier gene family SLC21A). We, therefore, studied whether GL is a potential transport substrate of the OATPs of rat and human liver. Because transport of GL could not be measured directly, GL-mediated cis-inhibition of [3H]estrone-3-sulfate or [35S]bromosulfophthalein uptake was analyzed kinetically in Xenopus laevis oocytes injected with cRNA coding for OATPs. GL inhibited [3H]estrone-3-sulfate uptake by 75-100% in oocytes expressing rat Oatp4, human OATP-C or human OATP8, members of the OATP1B subfamily that are expressed predominantly in hepatocytes. Dixon plots indicated a non-competitive type of inhibition, with Ki values of 6.1, 15.9 and 12.5 mumol/l, respectively. In contrast, GL inhibition of rat Oatp1, Oatp2 and Oatp3 and human OATP-A and OATP-B was only between 0 and 53%. In conclusion, GL is an inhibitor and, therefore, potentially a transport substrate of the liver-specific OATPs in rat and man. The rate at which GL is taken up into the liver may depend upon the function and expression levels of these hepatocellular OATPs.