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Keywords = urine osmolality

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12 pages, 915 KB  
Article
Association Between Plasma Cystatin C Concentration and Urine Osmolality in Adults with Different Forms of Beta-Thalassemia: A Cross-Sectional Study in Vietnam
by Loan Do Thi Thanh, Anh Nguyen Ngoc, Kien Nguyen Trung, Ha Nguyen Thi Thu, Dung Nguyen Huu and Thang Le Viet
Thalass. Rep. 2026, 16(2), 8; https://doi.org/10.3390/thalassrep16020008 - 6 May 2026
Viewed by 189
Abstract
Objective: To determine plasma cystatin C concentrations, urine osmolality and their relationship with disease severity in beta-thalassemia patients. Methods: A cross-sectional study was conducted on 234 patients with beta-thalassemia, including equal numbers (78 each) of beta-thalassemia major, intermedia, and minor cases, along with [...] Read more.
Objective: To determine plasma cystatin C concentrations, urine osmolality and their relationship with disease severity in beta-thalassemia patients. Methods: A cross-sectional study was conducted on 234 patients with beta-thalassemia, including equal numbers (78 each) of beta-thalassemia major, intermedia, and minor cases, along with 78 healthy individuals matched for age, sex, and body mass index, who served as the control group. Plasma cystatin C concentrations were quantified in all subjects using the ELISA method, and urine osmolality level was measured automatically on a FISKE 210 machine (USA). Results: The proportion of beta-thalassemia patients with increased plasma cystatin C concentration was 39.3% and the proportion with a decreased urine osmolality level was 67.5% compared with the control group. Plasma ferritin had predictive value for increased plasma cystatin C concentration (cut-off point: 567.5 ng/mL; AUC = 0.803) and decreased urine osmolality level (cut-off point: 488.15 ng/mL; AUC = 0.820), p < 0.001. Plasma cystatin C concentration increased gradually and urine osmolality level decreased gradually from minor beta-thalassemia to intermedia beta-thalassemia to major beta-thalassemia patients, with p < 0.001. Conclusions: Increased plasma cystatin C concentrations and decreased urine osmolality levels are common and are associated with severity in beta-thalassemia patients. Full article
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13 pages, 1352 KB  
Article
Urine-to-Serum Osmolality Ratio as a Prognostic Marker in Traumatic Brain Injury
by Eun Young Kim and Jeong-Am Ryu
Diagnostics 2026, 16(7), 1071; https://doi.org/10.3390/diagnostics16071071 - 2 Apr 2026
Viewed by 441
Abstract
Background/Objectives: Prognostication in traumatic brain injury (TBI) remains challenging. The urine-to-serum osmolality (U/S) ratio may reflect hypothalamic–pituitary axis integrity, a critical but underexplored prognostic domain. We investigated whether the U/S ratio provides early prognostic value and enhances prediction when combined with conventional [...] Read more.
Background/Objectives: Prognostication in traumatic brain injury (TBI) remains challenging. The urine-to-serum osmolality (U/S) ratio may reflect hypothalamic–pituitary axis integrity, a critical but underexplored prognostic domain. We investigated whether the U/S ratio provides early prognostic value and enhances prediction when combined with conventional severity markers. Methods: This retrospective study included 128 adult TBI patients admitted to a neurosurgical intensive care unit (ICU) with simultaneous osmolality measurements within 6 h of admission. The primary outcome was ICU mortality; the secondary outcome was poor neurological outcomes (Glasgow Outcome Scale 1–3). Results: ICU mortality was 14.1% (18/128), and poor neurological outcome occurred in 41.8% (46/110). Non-survivors had significantly lower U/S ratios than survivors (1.09 ± 0.58 vs. 1.70 ± 0.68, p < 0.001). For ICU mortality, U/S ratios (AUC = 0.803) showed similar discriminative ability to GCS (AUC = 0.806). For poor neurological outcomes, the U/S ratio (AUC = 0.768) significantly outperformed both GCS (AUC = 0.641, p = 0.038) and the Acute Physiology and Chronic Health Evaluation (APACHE) II score (AUC = 0.553, p < 0.001). Combining the U/S ratio with GCS improved mortality prediction (AUC = 0.890), as did combinations with the APACHE II score (AUC = 0.847). The U/S ratio remained independently associated with ICU mortality and poor neurological outcomes after adjusting for GCS or APACHE II scores. Quartile analyses revealed a dose–response relationship, with ICU mortality of 34.4% in Q1 versus 3.1% in Q4 (p for trend < 0.001). Prognostic value was preserved in patients receiving osmotic therapy (n = 86). Conclusions: The U/S ratio is a simple, readily available biomarker that independently predicts mortality and poor neurological outcomes in TBI patients. Particularly for neurological outcome predictions, it outperforms GCS or the APACHE II score alone. Combined with established severity scores, it may serve as a practical bedside tool reflecting hypothalamic–pituitary function in neurocritical care. Full article
(This article belongs to the Section Clinical Diagnosis and Prognosis)
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13 pages, 1684 KB  
Article
Renoprotective Effects of Goreisan via Modulation of RAAS Activity, Oxidative Stress, and AQP2 Trafficking in a Rat Model of Nephrotic Syndrome
by Mao Shimizu, Shunsuke Goto, Satoshi Yamatani, Kazuo Sakamoto, Keiji Kono and Hideki Fujii
Biomedicines 2026, 14(1), 8; https://doi.org/10.3390/biomedicines14010008 - 19 Dec 2025
Viewed by 702
Abstract
Background/Objectives: We evaluated Goreisan, a traditional Chinese medicine, for its effects on nephrotic syndrome in a rat model. Methods: Male Sprague–Dawley rats underwent right nephrectomy at 5 weeks of age, followed by adriamycin administration (5 mg/kg) at 6 and 8 weeks of [...] Read more.
Background/Objectives: We evaluated Goreisan, a traditional Chinese medicine, for its effects on nephrotic syndrome in a rat model. Methods: Male Sprague–Dawley rats underwent right nephrectomy at 5 weeks of age, followed by adriamycin administration (5 mg/kg) at 6 and 8 weeks of age to induce nephrotic syndrome. At 10 weeks, rats were divided into three groups: vehicle (control), Goreisan 0.5 g/kg (GL), and Goreisan 1.0 g/kg (GH). Goreisan was administered daily for 4 weeks. At 14 weeks, blood, urine, mRNA expressions, and kidney histopathology were analyzed. Data were analyzed using one-way ANOVA followed by Tukey–Kramer post hoc testing. Results: Goreisan prevented worsening kidney function, with reduced glomerular and tubulointerstitial damage, lower systemic and intrarenal 8-hydroxy-2′-deoxyguanosine levels, and lower plasma aldosterone levels and expression of intrarenal renin–angiotensin–aldosterone system (RAAS)-related factors. Urine volume significantly increased in GL and GH groups compared with the control group. In the GH group, urine volume increased markedly (Δ urine volume: 10.0 ± 2.6 mL/day), whereas it tended to decrease in the Vehicle group (Δ urine volume: −1.3 ± 2.5 mL/day). Urine osmolality was lower in the GH group, with a larger decrease in Δ urine osmolality (−616.3 ± 132.8 mOsm/L). These changes occurred without an increase in urinary sodium excretion, suggesting an aquaretic effect independent of natriuresis. Creatinine clearance (CCr/kg) declined markedly in the Vehicle group but was significantly preserved in the GH group (Δ CCr/kg: −2.2 ± 0.19 vs. −0.7 ± 0.28), indicating renoprotective effects. No differences were found in serum arginine–vasopressin levels. Real-time PCR and immunohistochemical staining showed no significant differences in aquaporin (AQP) mRNA expression (AQP1, AQP2, AQP3, and AQP4), but AQP2 localization to the apical membrane in the collecting ducts was reduced with Goreisan treatment. Conclusions: Goreisan demonstrates kidney-protective and diuretic effects in nephrotic syndrome, potentially through reducing systemic oxidative stress, modulating RAAS activation, and altering AQP2 trafficking. Full article
(This article belongs to the Section Molecular and Translational Medicine)
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17 pages, 810 KB  
Article
Hormonal and Osmoregulatory Responses in Intraoperative High-Volume Diuresis During Off-Pump Coronary Artery Bypass Grafting: An Exploratory Cohort Study
by Yuxi Hou, Shuwen Li, Fei Cai, Fangyi Luo and Jun Ma
J. Clin. Med. 2025, 14(23), 8395; https://doi.org/10.3390/jcm14238395 - 26 Nov 2025
Cited by 1 | Viewed by 815
Abstract
Background: Intraoperative high-volume diuresis is a frequent but underrecognized complication in cardiac surgery, potentially leading to hypovolemia, electrolyte imbalances, and hemodynamic instability. Its mechanisms remain poorly defined. This study investigated the hormonal and biochemical regulation of urine output during off-pump coronary artery [...] Read more.
Background: Intraoperative high-volume diuresis is a frequent but underrecognized complication in cardiac surgery, potentially leading to hypovolemia, electrolyte imbalances, and hemodynamic instability. Its mechanisms remain poorly defined. This study investigated the hormonal and biochemical regulation of urine output during off-pump coronary artery bypass grafting (OPCABG). Methods: For this single-center observational cohort study, 70 patients undergoing OPCABG were enrolled (diuresis: urine output > 5 mL/kg/h, n = 38; normal, n = 32). Hormonal markers and osmolality parameters were measured perioperatively. Logistic regression was used to identify independent predictors, and receiver operating characteristic (ROC) curves was used to assess model performance. Results: Intraoperative high-volume diuresis occurred in 54.2% of patients. Logistic regression identified a low Body Mass Index (BMI) (OR 0.72, p = 0.002), reduced albumin (OR 0.75, p = 0.014), and lower copeptin (OR 0.43, p = 0.037) as independent predictors (AUC 0.855). Perioperatively, NT-proBNPT0 rose in both groups, aldosterone increased only in the diuresis group, and copeptin showed a slight nonsignificant rise. Plasma sodium was higher in cases of diuresis at the end of surgery (148.4 vs. 144.9 mmol/L, p < 0.001). Despite greater urine output and fluid infusion, the rates of intensive care unit (ICU) admission and hospital stays were similar. Conclusions: Intraoperative high-volume diuresis in OPCABG is strongly associated with reduced antidiuretic hormone activity, suggesting a partial central diabetes insipidus-like mechanism. Although not affecting short-term outcomes, it posed challenges for intraoperative fluid and electrolyte management. Larger multicenter studies are needed for validation. Full article
(This article belongs to the Special Issue Advances in Anesthesia for Cardiac Surgery)
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10 pages, 384 KB  
Article
Estimated Osmolality by Measured Conductivity in 24 h Urine Renal Stone Patients: A Useful Tool for Monitoring Dietary Sodium and Protein Excess
by Louange Luemba Sita, Pitchouna Ingole Mboliasa, Ernest Kiswaya Sumaili, Vincent Frochot, Remi Chieze, Emmanuel Letavernier, Jérémie Muwonga Masidi, Mireille Nganga Nkanga, Michel Daudon and Jean Philippe Haymann
J. Clin. Med. 2025, 14(19), 6898; https://doi.org/10.3390/jcm14196898 - 29 Sep 2025
Viewed by 1534
Abstract
Background/Objectives: Monitoring of 24 h urine analysis is currently used to assess diet-related stone risk factors due in most cases to low hydration and high osmole intake accounting for urine supersaturation. The aim of our study is to test whether urine conductivity could [...] Read more.
Background/Objectives: Monitoring of 24 h urine analysis is currently used to assess diet-related stone risk factors due in most cases to low hydration and high osmole intake accounting for urine supersaturation. The aim of our study is to test whether urine conductivity could be a relevant surrogate marker of urine osmolality and a useful tool for monitoring salt and protein diets in primary care centers. Methods: 113 patients with kidney stone history referred for a routine evaluation of fasting and 24 h urine samples were included. Biochemical analysis of urine was performed, including measured osmolality (mUosm) and conductivity. Results: Among our population, 45% of patients have a low diuresis (high-risk group of stone recurrence) below the target of 2 L/day, with lower daily mUOsm and conductivity outflow compared to the low-risk patient group > 2 L/day (718 versus 852 mosm/Day, p < 0.0001, and 13,730 versus 17,890 mS/cm/day, p < 0.0001, respectively). Conversely to urine sodium and urea concentration, daily sodium and protein intake estimated by natriuresis and urea excretion are significantly lower in the high-risk group (p = 0.01 and <0.0001, respectively). In 24 h urine samples, osmolality and conductivity were strongly associated with diuresis. Moreover, a strong association between urinary osmolality and urine conductivity enables an estimated osmolality (eUosm) according to the following equation: eUosm = −41.656 + 0.057 × conductivity (r2 = 0.93; p < 0.001) with a 95% limit of agreement (LoA) ranging from −7.2% to +7.3%. An eUosm threshold value < 900 mOsm/day is independently associated with sodium and protein intake targets (odd ratio: 19.2 and 6.4-fold, respectively, p < 0.0001 and 0.01). Conclusions: 24 h urine measured conductivity appears to be a reliable, easy-to-use tool for the screening and monitoring of diet-related stone patients in primary care centers. Full article
(This article belongs to the Section Nephrology & Urology)
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9 pages, 2288 KB  
Case Report
McKittrick–Wheelock Syndrome, a Rare Cause of Nonresponsive Persistent Dyselectrolytemia
by Daniela Cana Ruiu, Mihaela Cheie, Mirela Marinela Florescu, Andreea Doriana Stanculescu, Carmen Popescu, Daniela-Teodora Maria, Sebastian Constantin Toma, Naomi Fota, Daniela Calina and Bogdan Silviu Ungureanu
Diagnostics 2025, 15(19), 2459; https://doi.org/10.3390/diagnostics15192459 - 26 Sep 2025
Viewed by 1206
Abstract
Case Presentation: A 67-year-old man presented with transient loss of consciousness and dizziness after weeks of vomiting, weakness, and recurrent syncopal episodes. Initial laboratory findings showed hyponatremia (Na 125 mEq/L), severe hypokalemia (K 2.3 mEq/L), hypochloremia (Cl 77 mEq/L), metabolic alkalemia (pH 7.5; [...] Read more.
Case Presentation: A 67-year-old man presented with transient loss of consciousness and dizziness after weeks of vomiting, weakness, and recurrent syncopal episodes. Initial laboratory findings showed hyponatremia (Na 125 mEq/L), severe hypokalemia (K 2.3 mEq/L), hypochloremia (Cl 77 mEq/L), metabolic alkalemia (pH 7.5; HCO3 34 mEq/L), low serum osmolality (263 mOsm/L) with inappropriately concentrated urine (332 mOsm/kg), and prerenal azotemia (creatinine 3.4 mg/dL; eGFR 19 mL/min/1.73 m2; blood urea 209 mg/dL). Contrast-enhanced CT, along with colonoscopy, identified a large mucus-secreting villous adenoma in the upper rectum. After fluid and electrolyte replacement, the patient underwent surgical resection with complete remission of symptoms and correction of electrolyte abnormalities on follow-up. Conclusion: Rectal villous adenomas should be considered in older adults with unexplained hypovolemia, hypokalemic hyponatremia, and metabolic alkalemia. Early recognition and definitive resection are curative and prevent kidney injury. Full article
(This article belongs to the Special Issue Nephrology: Diagnosis and Management)
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10 pages, 501 KB  
Case Report
A Novel Pathogenic Variant of the AVPR2 Gene Leading to Arginine Vasopressin Resistance Since the Neonatal Period
by Agnieszka Szmigielska, Piotr Skrzypczyk, Dorota Czapczak, Marta Dux, Adam Lipka, Beata Pyrżak and Anna Małgorzata Kucharska
Genes 2025, 16(8), 989; https://doi.org/10.3390/genes16080989 - 21 Aug 2025
Cited by 1 | Viewed by 1594
Abstract
Background: Diabetes insipidus (DI) in newborns is an extremely rare condition, with the age of presentation strongly suggesting a genetic background of the disease. The differential diagnosis should include arginine vasopressin deficiency (AVD) and arginine vasopressin resistance (AVR). Some novel diagnostic tools [...] Read more.
Background: Diabetes insipidus (DI) in newborns is an extremely rare condition, with the age of presentation strongly suggesting a genetic background of the disease. The differential diagnosis should include arginine vasopressin deficiency (AVD) and arginine vasopressin resistance (AVR). Some novel diagnostic tools such as copeptin evaluation and genetic tests are vital for early diagnosis. Case report: We present the case of a 1-month-old boy with polyuria observed since birth. Laboratory tests showed persistent hypernatremia, elevated plasma and low urine osmolality. An attempt at oral administration of desmopressin had no effect; additionally the copeptin level was increased. A genetic study (NGS of the AVP, AVPR2 and AQP2 genes) was considered and a new pathogenic variant in the AVPR2 gene (hemizygous c.157del) was detected. After the genetic test result was obtained, treatment with hydrochlorothiazide was started. The patient is now 3 months old, developing normally, and the weight and height are normal. Conclusions: Newborns with DI should be subjected to extensive multidisciplinary diagnostics, including endocrine and renal causes. Copeptin evaluation and prompt genetic diagnosis allows for the early diagnosis and implementation of appropriate treatment. Full article
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19 pages, 579 KB  
Article
Association Between Health-Related Behaviors and Health Status and Hydration Status in Polish Adults
by Joanna Frąckiewicz and Kacper Szewczyk
Nutrients 2025, 17(16), 2597; https://doi.org/10.3390/nu17162597 - 9 Aug 2025
Cited by 1 | Viewed by 1720
Abstract
Objectives: The health of the adult population is the result of many interacting variables, with health behaviors and lifestyle playing a key role. This study aimed to identify associations among health-related behaviors and health and hydration status in Polish adults. Methods: The completion [...] Read more.
Objectives: The health of the adult population is the result of many interacting variables, with health behaviors and lifestyle playing a key role. This study aimed to identify associations among health-related behaviors and health and hydration status in Polish adults. Methods: The completion of a beverage frequency questionnaire (FFQ) was undertaken by a total of 337 participants. Blood pressure (BP), anthropometric parameters, and body composition were measured. Urine samples were analyzed for specific gravity (USG), osmolality (Uosm), and potential hydrogen value (pH). Health-related behaviors were assessed using the Health Index Score (HIS), classifying participants into two groups: unhealthy habits (0–2 HIS group) and healthy habits (3–5 HIS group). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Results: Approximately 30% of participants (n = 115) exhibited unhealthy habits. Individuals in the 0–2 HIS group were more likely to be male, smoke, have low physical activity, be overweight or obese, sleep < 6 h, and/or consume alcohol ≥ 2 times/week. In contrast, higher HIS (3–5) was associated with female gender, non-smoking, moderate-to-high physical activity, normal body mass index (BMI), adequate sleep, and consuming alcohol < 2 times/week. Fatigue during the day (OR: 1.45), waist circumference (WC) (OR: 1.35), and Uosm (OR: 1.87) increased un-healthy habits. Conversely, greater consumption of non-carbonated mineral water (OR: 0.54) was linked to lower unhealthy habits. Conclusions: The HIS and hydration-related parameters can complement the assessment of the health status of the adult population and the identification of groups requiring special support in health promotion interventions. Full article
(This article belongs to the Special Issue Hydration and Nutrition Status in Human Health)
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18 pages, 5815 KB  
Article
Novel Lipid Biomarkers of Chronic Kidney Disease of Unknown Etiology Based on Urinary Small Extracellular Vesicles: A Pilot Study of Sugar Cane Workers
by Jie Zhou, Kevin J. Kroll, Jaime Butler-Dawson, Lyndsay Krisher, Abdel A. Alli, Chris Vulpe and Nancy D. Denslow
Metabolites 2025, 15(8), 523; https://doi.org/10.3390/metabo15080523 - 2 Aug 2025
Viewed by 1533
Abstract
Background/Objectives: Chronic kidney disease of unknown etiology (CKDu) disproportionately affects young male agricultural workers who are otherwise healthy. There is a scarcity of biomarkers for early detection of this type of kidney disease. We hypothesized that small extracellular vesicles (sEVs) released into urine [...] Read more.
Background/Objectives: Chronic kidney disease of unknown etiology (CKDu) disproportionately affects young male agricultural workers who are otherwise healthy. There is a scarcity of biomarkers for early detection of this type of kidney disease. We hypothesized that small extracellular vesicles (sEVs) released into urine may provide novel biomarkers. Methods: We obtained two urine samples at the start and the end of a workday in the fields from a limited set of workers with and without kidney impairment. Isolated sEVs were characterized for size, surface marker expression, and purity and, subsequently, their lipid composition was determined by mass spectrometry. Results: The number of particles per ml of urine normalized to osmolality and the size variance were larger in workers with possible CKDu than in control workers. Surface markers CD9, CD63, and CD81 are characteristic of sEVs and a second set of surface markers suggested the kidney as the origin. Differential expression of CD25 and CD45 suggested early inflammation in CKDu workers. Of the twenty-one lipids differentially expressed, several were bioactive, suggesting that they may have essential functions. Remarkably, fourteen of the lipids showed intermediate expression values in sEVs from healthy individuals with acute creatinine increases after a day of work. Conclusions: We identified twenty-one possible lipid biomarkers in sEVs isolated from urine that may be able to distinguish agricultural workers with early onset of CKDu. Differentially expressed surface proteins in these sEVs suggested early-stage inflammation. This pilot study was limited in the number of workers evaluated, but the approach should be further evaluated in a larger population. Full article
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11 pages, 1914 KB  
Case Report
Case Report of Nephrogenic Diabetes Insipidus with a Novel Mutation in the AQP2 Gene
by Alejandro Padilla-Guzmán, Vanessa Amparo Ochoa-Jiménez, Jessica María Forero-Delgadillo, Karen Apraez-Murillo, Harry Pachajoa and Jaime M. Restrepo
Int. J. Mol. Sci. 2025, 26(15), 7415; https://doi.org/10.3390/ijms26157415 - 1 Aug 2025
Viewed by 4812
Abstract
Nephrogenic diabetes insipidus (NDI) is a rare hereditary disorder characterized by renal resistance to arginine vasopressin (AVP), resulting in the kidneys’ inability to concentrate urine. Approximately 90% of NDI cases follow an X-linked inheritance pattern and are associated with pathogenic variants in the [...] Read more.
Nephrogenic diabetes insipidus (NDI) is a rare hereditary disorder characterized by renal resistance to arginine vasopressin (AVP), resulting in the kidneys’ inability to concentrate urine. Approximately 90% of NDI cases follow an X-linked inheritance pattern and are associated with pathogenic variants in the AVPR2 gene, which encodes the vasopressin receptor type 2. The remaining 10% are attributed to mutations in the AQP2 gene, which encodes aquaporin-2, and may follow either autosomal dominant or recessive inheritance patterns. We present the case of a male infant, younger than nine months of age, who was clinically diagnosed with NDI at six months. The patient presented recurrent episodes of polydipsia, polyuria, dehydration, hypernatremia, and persistently low urine osmolality. Despite adjustments in pharmacologic treatment and strict monitoring of urinary output, the clinical response remained suboptimal. Given the lack of improvement and the radiological finding of an absent posterior pituitary (neurohypophysis), the possibility of coexistent central diabetes insipidus (CDI) was raised, prompting a therapeutic trial with desmopressin. Nevertheless, in the absence of clinical improvement, desmopressin was discontinued. The patient’s management was continued with hydrochlorothiazide, ibuprofen, and a high-calorie diet restricted in sodium and protein, resulting in progressive clinical stabilization. Whole-exome sequencing identified a novel homozygous missense variant in the AQP2 gene (c.398T > A; p.Val133Glu), classified as likely pathogenic according to the American College of Medical Genetics and Genomics (ACMG) criteria: PM2 (absent from population databases), PP2 (missense variant in a gene with a low rate of benign missense variation), and PP3 (multiple lines of computational evidence supporting a deleterious effect)]. NDI is typically diagnosed during early infancy due to the early onset of symptoms and the potential for severe complications if left untreated. In this case, although initial clinical suspicion included concomitant CDI, the timely initiation of supportive management and the subsequent incorporation of molecular diagnostics facilitated a definitive diagnosis. The identification of a previously unreported homozygous variant in AQP2 contributed to diagnostic confirmation and therapeutic decision-making. The diagnosis and comprehensive management of NDI within the context of polyuria-polydipsia syndrome necessitates a multidisciplinary approach, integrating clinical evaluation with advanced molecular diagnostics. The novel AQP2 c.398T > A (p.Val133Glu) variant described herein was associated with early and severe clinical manifestations, underscoring the importance of genetic testing in atypical or treatment-refractory presentations of diabetes insipidus. Full article
(This article belongs to the Special Issue A Molecular Perspective on the Genetics of Kidney Diseases)
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15 pages, 2064 KB  
Article
A Low-Sugar Flavored Beverage Improves Fluid Intake in Children During Exercise in the Heat
by Sajjad Rezaei, Rocio I. Guerrero, Parker Kooima, Isabela E. Kavoura, Sai Tejaswari Gopalakrishnan, Clarissa E. Long, Floris C. Wardenaar, Jason C. Siegler, Colleen X. Muñoz and Stavros A. Kavouras
Nutrients 2025, 17(15), 2418; https://doi.org/10.3390/nu17152418 - 24 Jul 2025
Viewed by 4780
Abstract
Objectives: This study examined the impact of a low-sugar flavored beverage on total fluid intake and hydration biomarkers during intermittent exercise in a hot environment among healthy children. Methods: Twenty-one children (11 girls, 8–10 y) completed a randomized, crossover study with [...] Read more.
Objectives: This study examined the impact of a low-sugar flavored beverage on total fluid intake and hydration biomarkers during intermittent exercise in a hot environment among healthy children. Methods: Twenty-one children (11 girls, 8–10 y) completed a randomized, crossover study with two trials. Each trial involved three bouts of 10 min walking, 5 min rest, 10 min walking, and 35 min rest for a total of 3 h in a hot (29.9 ± 0.6 °C) and dry environment (26 ± 7% relative humidity). Walking intensity was 69 ± 7% of age-predicted maximum heart rate. Participants consumed either plain water (W) or a low-sugar flavored beverage (FB). Body weight, fluid intake, urine samples, and perceptual ratings were collected. Results: Total ad libitum fluid intake was significantly higher with the FB (946 ± 535 mL) than with W (531 ± 267 mL; p < 0.05). This difference was 128% higher for FB compared to W, with 19 out of the 21 children ingesting more fluids in FB versus W. Children rated the FB as more likable across all time points (p < 0.05). Net fluid balance was better with FB at 60, 70, 85, 135, and 145 min (p < 0.05), though not different at the 3 h mark. Urine volume was higher with FB (727 ± 291 mL) than with W (400 ± 293 mL; p < 0.05). Urine osmolality was significantly higher in the W trial at 120 and 180 min (p < 0.05). Conclusions: A flavored, low-sugar beverage enhanced ad libitum fluid intake and improved hydration markers compared to water during exercise in the heat, supporting its potential as a practical rehydration strategy for children. Full article
(This article belongs to the Section Pediatric Nutrition)
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15 pages, 2581 KB  
Article
Comparative Diagnostic Performance of Copeptin After Hypertonic Saline Infusion Versus Water Deprivation Test in Pediatric Patients with Polyuria–Polydipsia Syndrome
by Diana-Andreea Ciortea, Carmen Loredana Petrea (Cliveți), Iolanda Cristina Vivisenco, Sorin Ion Berbece, Gabriela Gurău, Mădălina Nicoleta Matei and Aurel Nechita
Int. J. Mol. Sci. 2025, 26(12), 5449; https://doi.org/10.3390/ijms26125449 - 6 Jun 2025
Cited by 3 | Viewed by 5279
Abstract
Differentiating central diabetes insipidus (CDI), nephrogenic diabetes insipidus (NDI), and primary polydipsia (PP) in pediatric patients with polyuria–polydipsia syndrome (PPS) remains a clinical challenge. The water deprivation test (WDT) is the traditional gold standard; however, it is time-consuming, burdensome, and prone to equivocal [...] Read more.
Differentiating central diabetes insipidus (CDI), nephrogenic diabetes insipidus (NDI), and primary polydipsia (PP) in pediatric patients with polyuria–polydipsia syndrome (PPS) remains a clinical challenge. The water deprivation test (WDT) is the traditional gold standard; however, it is time-consuming, burdensome, and prone to equivocal results. Stimulated copeptin, a surrogate marker of vasopressin, has emerged as a promising diagnostic alternative. We conducted a prospective, observational, cross-sectional study involving 27 pediatric patients (ages 2–17) presenting with PPS. Each patient underwent a WDT with desmopressin and hypertonic saline infusion (3% NaCl) for stimulated copeptin testing. Diagnostic accuracy was assessed using clinical diagnoses as a reference. The WDT showed high accuracy with an area under the curve (AUC) of 0.97, and there was an increased optimal threshold of ≥14% urine osmolality after desmopressin acetate (1-deamino-8-D-arginine vasopressin, DDAVP) administration (sensitivity 88.9%, specificity 100%). Stimulated copeptin at a threshold of <6.5 pmol/L demonstrated 100% sensitivity and specificity (AUC = 1.00) for CDI versus PP. Basal copeptin ≥21.4 pmol/L accurately identified all NDI cases. The agreement between the WDT and copeptin was low (κ = 0.06, McNemar p = 0.021), suggesting that copeptin has greater specificity, particularly for borderline or partial CDI. These results support the use of stimulated copeptin as a first-line diagnostic tool in pediatric PPS, offering improved objectivity, tolerability, and diagnostic clarity compared with the WDT. Basal copeptin also demonstrated excellent performance in rapid noninvasive NDI identification. Full article
(This article belongs to the Section Molecular Pathology, Diagnostics, and Therapeutics)
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9 pages, 198 KB  
Case Report
Hyponatraemia Induced by Terlipressin in Patients Diagnosed with Decompensated Liver Cirrhosis and Acute Variceal Bleeding
by Mahmoud Elshehawy, Richel Merin Panicker, Alaa Amr Abdelgawad, Patrick Anthony Ball and Hana Morrissey
Medicines 2025, 12(2), 7; https://doi.org/10.3390/medicines12020007 - 28 Mar 2025
Viewed by 1839
Abstract
Background: Hyponatraemia is a rare but potentially life-threatening complication of terlipressin therapy. Case history: In the current case, a 39-year-old female with decompensated liver cirrhosis (Child-Pugh C) and acute variceal bleeding experienced a precipitous decline in serum sodium—from 136 mmol/L to 115 mmol/L—within [...] Read more.
Background: Hyponatraemia is a rare but potentially life-threatening complication of terlipressin therapy. Case history: In the current case, a 39-year-old female with decompensated liver cirrhosis (Child-Pugh C) and acute variceal bleeding experienced a precipitous decline in serum sodium—from 136 mmol/L to 115 mmol/L—within 48 h of initiating terlipressin therapy. This was accompanied by marked fluid retention, reduced urine output, and symptoms of confusion and agitation. Laboratory tests confirmed dilutional hyponatraemia, characterized by urinary sodium <20 mmol/L and urine osmolality <100 mOsm/kg, indicating excessive free water reabsorption. Outcomes: The prompt discontinuation of terlipressin, fluid restriction and the cautious administration of hypertonic sodium chloride solution (2.7% NaCl) achieved a gradual normalization of sodium levels and resolution of symptoms. Fluid balance monitoring revealed a marked diuretic response following terlipressin cessation. This case aligns with existing reports, emphasizing the dual vasopressin receptor activity of terlipressin and its capacity to induce hyponatraemia, particularly in cirrhotic patients with preserved renal function and higher baseline sodium levels. Conclusions: This case and a literature review underscored the critical need for early fluid balance monitoring to detect retention. This case highlights the importance of individualized risk assessment, multidisciplinary management, and vigilant sodium correction to avoid complications. Practical recommendations are outlined to aid clinicians in the recognition and management of terlipressin-induced hyponatraemia. Full article
14 pages, 716 KB  
Article
Association Between Increased Dietary Sodium Intake and Higher Water Intake from Fluid and Food in Children
by Yi Zhang, Yongye Song, Shuai Cheng, Yunting Xia, Hongxing Li, Jiangping Huang, Luxi Xu and Na Zhang
Nutrients 2025, 17(7), 1099; https://doi.org/10.3390/nu17071099 - 21 Mar 2025
Cited by 1 | Viewed by 6297
Abstract
Background and Objectives: Maintaining an appropriate hydration status is crucial for promoting health. Children, who are in the process of growth and development, are at a higher risk of insufficient water intake and dehydration. This study aimed to compare water intake among [...] Read more.
Background and Objectives: Maintaining an appropriate hydration status is crucial for promoting health. Children, who are in the process of growth and development, are at a higher risk of insufficient water intake and dehydration. This study aimed to compare water intake among children with different levels of dietary sodium intake, and explore the relationship between hydration status, and dietary sodium intake and water intake. Methods: In this cross-sectional survey, 155 students in grades 4–6 from a primary school in Binyang County, Nanning, Guangxi, were recruited. Water intake from fluid was assessed using a validated 7-Day 24 h Fluid Intake Survey Questionnaire (days 1–7). Food intake was recorded and weighed using the duplicate diet method on days 5, 6, and 7. The water content in food was determined using the direct drying method, and dietary sodium intake was measured using inductively coupled plasma-optical emission spectrometry (ICP-OES). Urine osmolality was measured at two time points (morning and before afternoon classes) on days 5, 6, and 7 to assess hydration status. Results: A total of 155 participants (87 boys and 68 girls) completed the study, with a completion rate of 100%. The average dietary sodium intake, total water intake (TWI), water intake from fluid, and water intake from food were 1647 mg, 2039 mL, 956 mL, and 1175 mL, respectively. Among the participants, 19.4% exceeded the recommended sodium intake (2000 mg/day), 41.9% did not meet the adequate daily water intake from fluid, and 63.2% did not meet the adequate daily total water intake. When participants were divided into quartiles based on dietary sodium intake, significant differences were observed in water intake from fluid (p = 0.031) and food (p < 0.001). The water intake from fluid among participants in the HS1 (982 mL) and HS2 groups (997 mL) was higher than that among participants in LS2 (759 mL). Water intake from food increased progressively with increasing sodium intake (851 mL, 1075 mL, 1224 mL, and 1550 mL). Urine osmolality was associated with meeting the daily adequate water intake from fluid (p = 0.006), but not with exceeding the sodium intake standard (p = 0.787). There was no interaction between meeting the daily adequate water intake from fluid and exceeding the sodium intake standard (p = 0.413). Conclusions: Insufficient water intake was common among children. Children with a higher dietary sodium intake had a higher water intake from fluid and food. Urine osmolality was closely related to daily water intake from fluid, but not to sodium intake. Full article
(This article belongs to the Section Pediatric Nutrition)
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18 pages, 478 KB  
Article
Is There an Association Between Hydration Status, Beverage Consumption Frequency, Blood Pressure, Anthropometric Characteristics, and Urinary Biomarkers in Adults?
by Joanna Frąckiewicz and Kacper Szewczyk
Nutrients 2025, 17(6), 952; https://doi.org/10.3390/nu17060952 - 9 Mar 2025
Cited by 2 | Viewed by 4432
Abstract
Objectives: Hydration is essential for overall health; therefore, this study aimed to identify associations between hydration status and beverage consumption, anthropometric measures, and urine biochemical analyses in Polish adults. Poland was chosen due to potential regional dietary habits and hydration patterns that may [...] Read more.
Objectives: Hydration is essential for overall health; therefore, this study aimed to identify associations between hydration status and beverage consumption, anthropometric measures, and urine biochemical analyses in Polish adults. Poland was chosen due to potential regional dietary habits and hydration patterns that may influence hydration status. Methods: A total of 337 participants completed a beverage frequency questionnaire (FFQ). Blood pressure (BP), anthropometric parameters, and body composition were measured. Urine samples were analyzed for specific gravity (USG), osmolality (Uosm), and potential hydrogen value (pH). Hydration status was assessed using the WUT model (weight, urine color, thirst level), classifying participants into two groups: dehydrated (2-3 WUT components) and properly hydrated (0-1 WUT component). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Results: Approximately 50% of participants (n = 165) exhibited dehydration symptoms, including higher thirst levels, darker urine, and elevated USG and Uosm (p ≤ 0.05). Dehydrated individuals more frequently reported fatigue (p = 0.009), headaches (p = 0.024), and heavy legs (p = 0.002). Higher BMI (OR: 1.49), waist circumference (OR: 1.79), USG (OR: 2.29), and Uosm (OR: 1.75) increased dehydration risk. Conversely, greater consumption of tea (OR: 0.52) and non-carbonated mineral water (OR: 0.45), higher total body water (OR: 0.49), and handgrip strength (OR: 0.81) were linked to lower dehydration risk. Four dietary patterns were identified: Reasonable, Unhealthy, Minimalist, and Loving Sweet Beverages. Conclusions: Multifactorial hydration assessment, combined with preventive strategies such as regular fluid intake and weight management, may improve hydration. The WUT model and Venn diagram provide a practical tool for hydration assessment in clinical and public health. Full article
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