Arginine-stimulated copeptin inferior for diagnosing arginine vasopressin deficiency, but patients prefer arginine testing<\/p>\n<\/h3>\n
By Elana Gotkine HealthDay Reporter<\/b><\/p>\n
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THURSDAY, Nov. 16, 2023 (HealthDay News) — Arginine vasopressin (AVP) deficiency is more accurately diagnosed with hypertonic saline-stimulated copeptin than with arginine-stimulated copeptin among adults with polyuria polydipsia syndrome, according to a study published in the Nov. 16 issue of the New England Journal of Medicine<\/em>.<\/p>\n Julie Refardt, M.D., Ph.D., from the University Hospital Basel in Switzerland, and colleagues conducted a noninferiority trial involving adults with polydipsia and hypotonic polyuria or a known diagnosis of AVP deficiency to undergo diagnostic evaluation with hypertonic-saline stimulation and with arginine stimulation on different days. The final diagnosis was made by two endocrinologists independently with use of clinical information, treatment response, and hypertonic-saline test results.<\/p>\n A total of 158 patients underwent the two tests: 44 and 56 percent received the diagnosis of AVP deficiency and primary polydipsia, respectively. The researchers found that the diagnostic accuracy was 74.4 and 95.6 percent for arginine-stimulated copeptin and hypertonic saline-stimulated copeptin, respectively (estimated difference, \u00e2\u0088\u009221.2 percentage points). Seventy-two percent of patients preferred testing with arginine versus hypertonic saline. Arginine-stimulated copeptin at a \u00e2\u0089\u00a43.0 pmol\/L yielded an AVP deficiency diagnosis with specificity of 90.9 percent, and levels of >5.2 pmol\/L yielded a diagnosis of primary polydipsia with specificity of 91.4 percent.<\/p>\n “For the diagnosis of AVP deficiency, arginine-stimulated copeptin was inferior to hypertonic saline-stimulated copeptin, although arginine-stimulated copeptin was preferred by the trial patients,” the authors write.<\/p>\n Laboratory measurement of copeptin was funded by Thermo Fisher Scientific.<\/p>\n Abstract\/Full Text (subscription or payment may be required)<\/a><\/p>\n Editorial (subscription or payment may be required)<\/a><\/p>\n <\/i><\/p>\n