Fractional Urate Excretion in Nonedematous Hyponatremia

NCT01425125 · Status: WITHDRAWN · Phase: NA · Type: INTERVENTIONAL

Last updated 2019-02-06

No results posted yet for this study

Summary

Hyponatremia, defined as a serum sodium \< 135 mmol/l, in patients without edema has undergone significant changes where it is now evident that even mild hyponatremia should be treated because of its association with symptoms, especially a fourfold increase in falls over the age of 65 years. There is an unresolved controversy over the relative prevalence of the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) and cerebral/renal salt wasting (C/RSW). Resolution of this diagnostic dilemma becomes urgent because of divergent therapeutic goals, to water-restrict in SIADH or to give salt and water supplementation in C/RSW. The dilemma is compounded by recent reports of C/RSW occurring in patients without cerebral disease, thus adding further confusion in defining the relative prevalence of both syndromes. Because of overlapping laboratory and clinical findings in both syndromes, only differences in the state of extracellular volume differentiates one syndrome from the other, being high normal to increased in SIADH and decreased in C/RSW. The investigators have used fractional excretion (FE) of urate to categorize patients with hyponatremia. The increased FEurate that is observed in hyponatremic patients with SIADH and C/RSW can be used to differentiate both syndromes by correcting the hyponatremia and determining whether FEurate normalizes as in SIADH or remains increased in C/RSW. The present studies have been designed to determine total body water by deuterium and extracellular water by sodium bromide in patients with nonedematous hyponatremia with normal and increased FEurate to differentiate more conclusively whether the patient has normal or decreased water volumes. The investigators will also correct serum sodium rapidly with judicious administration of hypertonic saline over approximately three days and determine whether FEurate normalizes as in SIADH or remains increased as in C/RSW. In another group of patients, The investigators have data to suggest that those with normal sodium and increased FEurate is consistent with C/RSW. The investigators intend to do the same water volume studies to determine whether an increased FEurate with normonatremia would have decreased total and extracellular water that these patients have C/RSW without the need to correct a prior hyponatremia.

Conditions

  • Cerebral Hyponatremia
  • SIADH
  • Cerebral Salt-wasting Syndrome
  • Reset Hypothalamic Osmostat

Interventions

DRUG

Tolvaptan in euvolemic hyponatremia

This arm will test the effectiveness of tolvaptan in treating the hyponatremia of patients with euvolemic hyponatremia.

Sponsors & Collaborators

Principal Investigators

  • John K Maesaka, MD · Winthrop University Hospital

  • Louis J Imbriano, MD · Winthrop University Hospital

Study Design

Allocation
NA
Purpose
DIAGNOSTIC
Masking
NONE
Model
SINGLE_GROUP

Eligibility

Min Age
18 Years
Sex
ALL
Healthy Volunteers
No

Timeline & Regulatory

Start
2011-11-30
Primary Completion
2014-12-31
Completion
2014-12-31

Countries

  • United States

Study Locations

More Related Trials

Entities

Read the full study record

This page highlights key information. For complete eligibility criteria, study locations, investigator contacts, and the full protocol, visit the original record on ClinicalTrials.gov.

View NCT01425125 on ClinicalTrials.gov