Association between hypouricaemia and jaundice

Increased Serum Uric Acid over five years is a Risk Factor for Developing Fatty Liver

The prevalence of fatty liver disease (FLD) is increasing. To clarify risk factors for developing FLD, we analyzed a database from healthy Japanese adults who had annual medical check-ups in 2004 and reexamined in 2009. We used the fatty liver index (FLI) to classify participants as FLD (FLI ≥60), borderline FLD (30≤ FLI <60), and normal liver (FLI <30). Subjects with hepatitis B or C virus infection and subjects with FLD at the baseline were excluded. The cumulative incidence of FLD from normal liver and from borderline FLD over five years were 0.65% (52/8,025) and 12.9% (244/1,888), respectively. After multiple adjustments, higher serum uric acid (SUA) (OR:1.92; 95% CI:1.40–2.63) and increased SUA change (OR:3.734; 95% CI:2.57–5.42) became risk factors for developing FLD from normal liver, as well as younger age and higher body mass index. The risk factors for developing FLD from borderline FLD were similar. Not only higher baseline SUA but also increased SUA change became independent risks for developing FLD.

Normal urate transport into erythrocytes in familial renal hypouricemia and in the Dalmatian dog

It has been hypothesized that humans with familial renal hypouricemia may have a generalized defect of urate transport across cell membranes due to the genetic deletion of a specific carrier, a defect similar to that reported in the Dalmatian dog. In this study the transport of urate labelled with carbon 14 by the erythrocytes of four patients with familial renal hypouricemia was identical to that of five healthy controls. The addition of hypoxanthine to the incubation medium inhibited the transport to a similar extent in the two groups of patients, demonstrating the presence of a carrier specific for urate. This carrier was also found to be present in the erythrocytes of Dalmatian and mongrel dogs. Thus, the renal anomaly causing the hypouricemia in both species is not related to a generalized deletion of a urate-transporting protein on cell membranes.

About some common biochemical and pharmacological properties of bile salts and non steroidal anti-inflammatory drugs

Glyco- and tauro-deoxycholate, -chenodeoxycholate, -dehydrocholate and -cholate uncouple the mitochondrial oxidative phosphorylation in this order of potency. They also induce pseudo-energized mitochondrial swelling and lymphocyte swelling in the same order of potency. Similar swelling properties were observed for glyco- and tauro-lithocholate. Glyco- and tauro-deoxycholate induce alkalinization of the intra-mitochondrial space as determined on bromothymol blue pre-loaded mitochondria. These two bile salts conjugates also increase the amount of -SH groups available on lymphocyte membranes for sulfhydryl-disulfide interchange reactions. All these biochemical properties have been described for non-steroidal anti-inflammatory drugs. They could thus be implicated in the jaundice remission observed in various inflammatory states.

Hypouricaemia and increased renal urate clearance associated with hyperparathyroidism

A 64-year-old female was found to have hypouricaemia, with serum uric acid ranging from 0.06-0.12 mmol/l (1.1-2.0 mg/100 ml), associated with an increased urate clearance of 48.9 ml/min and hyperparathyroidism. Known causes of increased uric acid clearance were excluded. Pyrazinamide reduced urate clearance dramatically to 2.1 ml/min, suggesting that the tubular defect was either one of increased secretion or a failure of postsecretory reabsorption. No other tubular abnormality was apparent except diminished urine concentrating ability. Hypouricaemia has not been previously reported in association with hyperparathyroidism and a mechanism relating the two disorders could not be readily postulated. The tubular defect shown in this instance resembled that reported in association with Wilson's disease and Hodgkin's disease. This case and earlier reports of isolated tubular defects of uric acid handling enhance our understanding of uric acid excretion.