English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Background/Aims:   Hyponatremia associated with high urinary fractional excretion of uric acid which persists after serum sodium is corrected is the cardinal feature of salt losing nephropathy (SLN). We hypothesize that low grade proximal tubular injury is present in SLN because the proximal tubule is the main site of uric acid and sodium transport.   Methods:   Five subjects with SLN were compared to four subjects with recurrent hyponatremia and three healthy individuals. Urinary NGAL (neutrophil gelatinase associated lipocalin, a marker of tubular injury) and fasting urinary fructose levels (a marker of proximal tubular injury) were measured.   Results:   Subjects with SLN (n=5) showed elevated fractional uric acid excretion (22 ± 6 vs 4 ± 2 percent, p<0.0001), elevated urinary NGAL levels (62 ± 37 vs 9 ± 7 ng/mg creatinine, p=0.001) and fasting urinary fructose levels compared with the 7 controls (383 ± 465 vs 60 ± 34µmole/µg creatinine, p <0.001). A strong correlation between urinary NGAL levels and urinary fructose levels was observed (r =0.87, p‹0.001).   Conclusion:   High urinary fractional excretion of uric acid in SLN is associated with elevated NGAL and fasting urinary fructose levels suggesting that SLN may involve tubular injury.

Hyponatremia with Persistent Elevated Urinary Fractional Uric Acid Excretion: Evidence for Proximal Tubular Injury?