Use of copeptin in the differential diagnosis of diabetes insipidus
Research type
Research Study
Full title
Use of copeptin in the differential diagnosis of diabetes insipidus - a prospective international study (CODDI Study)
IRAS ID
141482
Contact name
Ashley Grossman
Contact email
Sponsor organisation
University of Basel, Switzerland
Clinicaltrials.gov Identifier
Duration of Study in the UK
2 years, 0 months, 1 days
Research summary
Polyuria and polydipsia syndrome (PPS) may result from a number of distinct diseases including diabetes insipidus (cranial/nephrogenic) and primary polydipsia. Careful differentiation is essential as treatment strategies vary substantially. Current diagnostic methods include measuring urinary concentration following dehydration (water deprivation test - WDT) and measuring plasma arginine vasopressin (AVP) levels during a hypertonic saline infusion. These tests claimed to allow definite diagnostic differentiation in >90% of cases, but recent data revealed poorer performance with overall diagnostic accuracy of 70% and 46% respectively.
Copeptin is a stable glycoprotein product of preprovasopressin which, in contrast to AVP, is measured readily and robustly. When measured during a WDT, copeptin levels have diagnostic accuracy in 94% of patients. This novel test for better differentiation of PPS requires prospective evaluation. This trial is part of an international study which aims to verify the diagnostic superiority of the WDT plus copeptin measurement compared to the WDT alone and WDT plus AVP measurement in the diagnosis of patients with PPS.
Individuals requiring investigation of PPS are eligible to participate. Those who consent to the trial will answer questions about their medical history and current symptoms. Routine physical examination and baseline diagnostics will include urine and blood sampling. If cranial imaging has not been performed, an MRI scan will be conducted. Participants will undergo both the hypertonic saline infusion test and the WDT on two separate days in the hospital endocrine unit, during which levels of copeptin will be measured. The participant is then discharged with a preliminary diagnosis and treatment regime based on results of the WDT alone (current gold standard). A follow-up visit at 3-4 months will assess the therapeutic response and re-evaluate the preliminary diagnosis as necessary. The results will be published in peer-reviewed medical journals and may influence guidelines for diagnosis of PPS.REC name
South Central - Oxford C Research Ethics Committee
REC reference
14/SC/1397
Date of REC Opinion
19 Dec 2014
REC opinion
Further Information Favourable Opinion