CONTEXT:The role of copeptin in assessing hyponatremic patients at emergency department (ED) admission remains debated. OBJECTIVE:This work aimed to assess copeptin's effectiveness in evaluating extracellular fluid (ECF) volume and its predictive value in hyponatremic adults admitted to the medical ED. METHODS:This work comprises a report from the IPSO-URG, a prospective cohort study with recruitment from June 2018 to August 2019 and 6-month follow-up. The setting is a medical ED of a single tertiary center. Patients included a consecutive sample of 123 adults with hyponatremia confirmed by direct and indirect ion-selective electrode assay after glucose correction. Excluding 33 individuals with missing consent or criteria and 6 without hypotonic hyponatremia, 84 patients were analyzed. Data included symptoms, vital signs, ultrasound, medical history, Charlson Comorbidity Index, and pretreatment blood and urine samples. ECF status was reassessed post discharge by 3 endocrinologists, blinded to copeptin results, who classified cases etiologically and resolved disagreements through discussion. In-hospital and 6-month mortality were recorded. RESULTS:A copeptin-to-urinary sodium (u-Na) ratio less than or equal to 29.5 pmol/mmol increased the likelihood of preserved ECF more than 4-fold (odds ratio 4.28; P = .026), outperforming standard u-Na (area under the curve difference 0.177; P = .013). Copeptin predicted in-hospital mortality (hazard ratio [HR] 1.005), with greater than 60.1 pmol/L as the optimal cutoff (P = .0005). Copeptin (HR 1.005; P = .02), N-terminal prohormone of brain natriuretic peptide (HR 1.004; P = .031), and comorbidity burden (HR 1.207; P = .009) predicted 6-month mortality, with copeptin greater than 13.6 pmol/L indicating a more than 4-fold risk (HR 4.507; P = .0001). CONCLUSION:Measuring copeptin on ED admission in hypotonic hyponatremia aids diagnosis and mortality prediction. The copeptin/u-Na index more accurately identifies preserved ECF than the standard u-Na cutoff.

Context Hirata’s disease (HD) is a rare autoimmune cause of hypoglycemia. Patients suffering from this condition have a genetic predisposition, determined by HLA DR4, with some differences in the worldwide population. In Caucasians HLA DRB1*0403 is the most frequent susceptibility background on which some drugs play as triggers. Case description We reported the case of a woman with several hypoglycemic episodes, characterized by high insulin and c-peptide levels. Biochemical and morphological exams excluded a neuroendocrine tumor. HD was diagnosed according to insulin autoantibodies positivity and patient’s history, particularly about drugs taken. The HLA analysis revealed DRB1*0415 allele. Conclusions We found a potential new predisposing factor for HD, HLA DRB1*0415 allele, never described before as genetic background to insulin autoimmune syndrome in Caucasians.

INTRODUCTION:Multiple studies tried to identify cortisol cut-offs after pituitary surgery that could accurately assess hypothalamic-pituitary-adrenal (HPA) axis function; however, there is no consensus nowadays. This study aimed to evaluate the accuracy of morning cortisol after transsphenoidal surgery in predicting long-term secondary adrenal insufficiency. METHODS:In our tertiary center, we prospectively determined first- and second-day cortisol after transsphenoidal surgery in 92 patients without preoperative adrenal -insufficiency and not treated with glucocorticoids perioperatively. Definitive diagnosis of secondary adrenal insufficiency was obtained with re-evaluation 3 months after trans-sphenoidal surgery and clinical follow-up of at least 1 year. RESULTS:Ten patients (10.8%) developed long-term postoperative secondary adrenal insufficiency. The ROC curves demonstrated that first-day cortisol had a moderate diagnostic accuracy, while a second-day cortisol ≤9.3 µg/dL (257 nmol/L) showed the best performance in predicting adrenal insufficiency (sensitivity [Se] 88.9%, specificity [Sp] 86.9%, AUC 0.921). Moreover, a second-day cortisol ≤3.2 µg/dL (89 nmol/L) was able to diagnose adrenal insufficiency in 100% of cases (Se 22.2%, Sp 100%) and >14 µg/dL (386 nmol/L) was able to exclude ACTH deficiency (Se 100%, Sp 57.4%). CONCLUSIONS:Adrenal function can be carefully studied on the second day after pituitary surgery, using cut-off values that international guidelines suggested for non-stressed conditions. In fact, second-day cortisol levels ≤3.2 μg/dL (89 nmol/L) and >14 μg/dL (386 nmol/L) are diagnostic of secondary adrenal insufficiency and normal function, respectively. We also suggest performing a definitive re-evaluation with an HPA axis stimulation test when second-day cortisol values are between 3.3 and 14 μg/dL (90-386 nmol/L).

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Introduction: Central diabetes insipidus (CDI) is a frequent complication of pituitary surgery, but its diagnosis lacks standardized criteria. Copeptin, a surrogate marker of arginine vasopressin release, is triggered by psycho-physical stresses such as pituitary surgery. Low postoperative copeptin could predict CDI onset. The aims of this study were the validation of copeptin as a predictor of post-neurosurgical CDI and the identification of the optimal timing for its determination. Methods: Sixty-six consecutive patients operated for a hypothalamic-pituitary lesion were evaluated. Copeptin was determined preoperatively and at 1, 6, 12, 24 and 48 h post-extubation. Fifty-eight patients were reassessed after 3–6 months post-surgery to confirm transient (3 cases) or permanent CDI (5 cases) diagnosis. Results: A marked copeptin peak was identified at 1 h after extubation, when a value below or equal to 12.8 pmol/L had a good accuracy in identifying CDI cases (AUC 0.866, 95% CI 0.751–0.941). Moreover, a copeptin peak above 4.2 pmol/L excluded permanent forms (AUC 1, 95% CI 0.629–1). Regression analysis identified copeptin as the only significant predictor of CDI (OR 0.86, 95% CI 0.75–0.98, p = 0.02). A copeptin T1/T0 ratio below or equal to 1.47 identified patients at risk of isolated biochemical alterations even in the absence of an overt CDI. Conclusions: A prompt increase of copeptin is expected at 1 h after extubation. The absence of this peak is a reliable predictor of post-neurosurgical CDI.