Primary Polydipsia in a Toddler: A Rare Case.

Primary polydipsia (PP) is a rare but significant clinical entity in pediatric patients. Here, we present the case of a 16-month-old female referred to our center due to recurrent episodes of electrolyte imbalances. Initially admitted for management of a viral illness, she experienced unexplained electrolyte disturbances, prompting subsequent admissions marked by similar disruptions. Despite stabilization and discharge, her condition persisted. Pre-referral laboratory findings revealed significant electrolyte abnormalities alongside polyuria symptoms. Investigations unveiled a history of frequent heavy wet diapers and increased thirst. Further tests including a water deprivation test excluded diabetes insipidus. Following the restriction of water intake and careful monitoring, her condition markedly improved. This case emphasizes the importance of thorough evaluation in persistent electrolyte imbalances in toddlers, highlighting the role of polyuria as a contributing factor and the efficacy of targeted interventions in managing such cases.

Oral Levodopa Stimulates Copeptin Secretion in Children and Adolescents with Intact Posterior Pituitary Function.

BACKGROUND: Copeptin stimulation tests can be used in the differential diagnosis of polyuria polydipsia syndrome. Current stimulation methods rely on intravenous or subcutaneous administration. Oral stimulus can further simplify the diagnostic approach. The levodopa stimulation test is widely used in the evaluation of growth hormone deficiency (GHD), and the dopamine pathway was reported to be associated with arginine vasopressin secretion. The study aimed to investigate the effect of oral levodopa on copeptin secretion. METHODS: The study was a prospective observational single-center cohort study. Patients < 18 years old with short stature and no symptoms of polyuria or polydipsia undergoing levodopa stimulation test for suspected GHD were recruited from May 2023 to Nov 2023. Copeptin and growth hormone (GH) were measured at 0, 30, 60, 90, and 120min in the levodopa test. The insulin tolerance test with copeptin and GH measured at the same time points was conducted in part of patients. RESULTS: Forty-four participants were included in the final analysis. In the levodopa stimulation test, the median (interquartile range, IQR) copeptin concentration increased from 5.20 (3.51, 8.25) pmol/L to maximum 19.36 (8.97, 108.08) pmol/L (P < 0.001), 3.94 (1.41, 13.88) times of the baseline (P < 0.001). Compared with insulin tolerance test, peak copeptin in the levodopa test was significantly higher (34.61 (13.67, 98.96) vs 8.88 (7.14, 15.42) pmol/L, P = 0.009). Higher copeptin was associated with larger dose of levodopa. CONCLUSIONS: Oral levodopa could be used to stimulate copeptin.

Hyponatremia Secondary to Psychogenic Polydipsia and Schizophrenia: A Case Report.

Psychogenic polydipsia is characterized by excess thirst, followed by the overconsumption of liquids. This condition is seen in an array of mental illnesses, especially schizophrenia. Psychogenic polydipsia can lead to hyponatremia, which can lead to neurologic sequelae, such as seizures, cerebral edema, and death. In the case under study, the patient presents with schizophrenia, fatigue, weakness, and dizziness during psychiatric follow-up. A comprehensive metabolic panel (CMP) was ordered, which indicated hyponatremia. This patient was treated with salt tablets and behavioral therapy, which led to the normalization of his serum sodium and symptom improvement. The patient has a history of psychogenic polydipsia with hyponatremia, treated on and off for years with salt replacement and water restriction. Management of psychogenic polydipsia is a difficult task. It is important to understand the available management options so that water intoxication and the consequences of hyponatremia do not occur.

Approach to the patient with suspected hypotonic polyuria.

Investigation and management of hypotonic polyura is a common challenge in clinical endocrinology. The three main causes, recently renamed to arginine vasopressin deficiency (AVP-D, formerly central diabetes insipidus), AVP-resistance (AVP-R, formerly nephrogenic diabetes insipidus), and primary polydipsia (PP) require accurate diagnosis as management differs for each. This new nomenclature more accurately reflects pathophysiology, and has now been adopted by the Systemised Nomenclature of Medicine (SNOMED). Advances in diagnosis over the last few years have centered around the use of copeptin measurement. Here, we use three patient case histories to highlight the use of this approach, and to demonstrate how it can succeed where other approaches, such as the water deprivation test, sometimes fail. We discuss the overall approach to each type of patient and the strengths and limitations of diagnostic strategies, illustrating the use of the new nomenclature.

Logistic regression analysis of risk factors influencing childhood enuresis: a comprehensive survey study.

OBJECTIVE: To identify risk factors associated with childhood enuresis. METHODS: We conducted a retrospective analysis of 146 children aged 6 to 13 years diagnosed with enuresis at Anhui Province Children's Hospital between June 2020 and June 2023. Children were categorized based on bedwetting frequency: those with less frequent episodes (once a week to twice a month) were placed in the mild group (60 cases), and those with frequent episodes (two or more times per week) were placed in the severe group (86 cases). We compared demographic data, family histories, and personal characteristics between the groups and performed logistic regression to determine significant risk factors. RESULTS: The analysis revealed that a stubborn personality, nocturnal polyuria, sleep-wake disorders, and bladder dysfunction significantly increased the risk of enuresis (P < 0.05). These findings underscore the importance of a holistic approach in evaluating psychological aspects, nocturnal urination patterns, sleep quality, and bladder health in managing enuresis. CONCLUSION: The study identifies stubborn personality, nocturnal polyuria, sleep-wake disorders, and bladder dysfunction as independent risk factors for childhood enuresis. Understanding these factors is crucial for developing targeted interventions that can enhance the management and outcomes of enuresis. Future research should explore the interrelationships among these factors to refine preventive and therapeutic strategies for early childhood enuresis.

Copeptin as a diagnostic and prognostic biomarker in pediatric diseases.

Arginine vasopressin (AVP) plays a main role in maintaining the homeostasis of fluid balance and vascular tone and in regulating the endocrine stress response in response to osmotic, hemodynamic and stress stimuli. However, the difficulty in measuring AVP limits its clinical application. Copeptin, the C-terminal part of the AVP precursor, is released in an equimolar concentration mode with AVP from the pituitary but is more stable and simple to measure. Therefore, copeptin has emerged as a promising surrogate marker of AVP with excellent potential for the diagnosis, differentiation and prognosis of various diseases in recent decades. However, its application requires further validation, especially in the pediatric population. This review focuses on the clinical value of copeptin in different pediatric diseases and the prospects for its application as a potential biomarker.

Establishment and validation of a predictive nomogram for polyuria during general anesthesia in thoracic surgery.

BACKGROUND: To develop and evaluate a predictive nomogram for polyuria during general anesthesia in thoracic surgery. METHODS: A retrospective study was designed and performed. The whole dataset was used to develop the predictive nomogram and used a stepwise algorithm to screen variables. The stepwise algorithm was based on Akaike's information criterion (AIC). Multivariable logistic regression analysis was used to develop the nomogram. The receiver operating characteristic (ROC) curve was used to evaluate the model's discrimination ability. The Hosmer-Lemeshow (HL) test was performed to check if the model was well calibrated. Decision curve analysis (DCA) was performed to measure the nomogram's clinical usefulness and net benefits. P < 0.05 was considered to indicate statistical significance. RESULTS: The sample included 529 subjects who had undergone thoracic surgery. Fentanyl use, gender, the difference between mean arterial pressure at admission and before the operation, operation type, total amount of fluids and blood products transfused, blood loss, vasopressor, and cisatracurium use were identified as predictors and incorporated into the nomogram. The nomogram showed good discrimination ability on the receiver operating characteristic curve (0.6937) and is well calibrated using the Hosmer-Lemeshow test. Decision curve analysis demonstrated that the nomogram was clinically useful. CONCLUSIONS: Individualized and precise prediction of intraoperative polyuria allows for better anesthesia management and early prevention optimization.

A novel AVPR2 gene mutation in a Chinese pedigree with nephrogenic diabetes insipidus.

Nephrogenic diabetes insipidus (NDI) is a rare genetic disorder primarily associated with mutations in the arginine vasopressin receptor 2 (AVPR2) gene or the aquaporin 2 (AQP2) gene, resulting in impaired water reabsorption in the renal tubules. This report describes a case of a young male patient with NDI from China with a history of polydipsia and polyuria for over 15 years. Laboratory examinations of the proband indicated low urine-specific gravity and osmolality. Urologic ultrasound revealed severe bilateral hydronephrosis in both kidneys, bilateral dilatation of the ureters, roughness of the bladder wall, and the formation of muscle trabeculae. The diagnosis of diabetes insipidus was confirmed by water deprivation tests. The administration of posterior pituitary hormone did not alter urine-specific gravity, and osmolality remained at a low level (<300 mOsm/kg). Based on these findings, and the genetic tests of the proband and his parents were performed. A missense mutation (c.616 G>C) in exon 3 of the AVPR2 gene of the proband was found, caused by the substitution of amino acid valine to leucine at position 206 [p.Val206Leu], which was a hemizygous mutation and consistent with X-chromosome recessive inheritance. The administration of oral hydrochlorothiazide improves the symptoms of polydipsia and polyuria in the proband. This novel AVPR2 gene mutation may be the main cause of NDI in this family, which induces a functional defect in AVPR2, and leads to reduced tubular reabsorption of water.

Polyuria in COVID-19 Patients Undergoing Extracorporeal Membrane Oxygenation.

Background: The COVID-19 pandemic caused an unprecedented number of patients requiring veno-venous extracorporeal membrane oxygenation (VV ECMO) therapy. Clinical polyuria was observed at our ECMO center during the pandemic. This study aims to investigate the incidence, potential causes, and implications of polyuria in COVID-19 patients undergoing VV ECMO therapy. Methods: Here, 68 SARS-CoV-2 positive patients receiving VV ECMO were stratified into the following two groups: polyuria (PU), characterized by an average urine output of ≥3000 mL/day within seven days following initiation, and non-polyuria (NPU), defined by <3000 mL/day. Polyuria in ECMO patients occurred in 51.5% (n = 35) within seven days after ECMO initiation. No significant difference in mortality was observed between PU and NPU groups (60.0% vs. 60.6%). Differences were found in the fluid intake (p < 0.01) and balance within 24 h (p = 0.01), creatinine (p < 0.01), plasma osmolality (p = < 0.01), lactate (p < 0.01), urea (p < 0.01), and sodium levels (p < 0.01) between the groups. Plasma osmolality increased (p < 0.01) after ECMO initiation during the observation period. Results: Diuresis and plasma osmolality increased during VV ECMO treatment, while mortality was not affected by polyuria. Conclusions: Polyuria does not appear to impact mortality. Further investigations are warranted to elucidate its underlying mechanisms and clinical implications in the context of VV ECMO therapy and COVID-19 management.

A challenging diagnosis of Langerhans' cell histiocytosis with hypothalamic-pituitary and mandibular involvement: case report and literature review.

Background: Langerhans cell histiocytosis (LCH) is a rare bone marrow derived neoplasm that mainly affects children. It is a multiorgan disorder and hypothalamic-pituitary involvement is uncommon. LCH reveals a wide spectrum of indications; thus, the diagnosis and treatment are usually challenging. Case Report: A 22-year-old male presented with polydipsia, polyuria with nonspecific radiological findings, later on, developed a mandibular lesion and a biopsy was conducted which led to LCH diagnosis. After many improper treatments due to unclear diagnosis, the patient was finally placed on chemotherapy and is now under surveillance. Discussion: LCH is a rare disease with diverse clinical manifestations affecting various organs. Associated mutations, such as BRAF V600E, contribute to its complexity. In adults, initial symptoms include pain, weight loss, and fever, with potential pituitary involvement leading to Arginine vasopressin (AVP) deficiency. Commonly affected organs include bone, skin, and the pituitary gland. The disease can be categorized into single-system and multisystem. Pathological diagnosis involves electron microscopy or immunohistochemical staining. Treatment options vary; the presented case utilized Desmopressin acetate and prednisolone before transitioning to cyclophosphamide for multisystemic LCH. Conclusion: AVP deficiency can suggest hypothalamic-pituitary LCH, and a biopsy, if possible, is recommended to confirm the diagnosis.

Effects of long-term desmopressin treatment for nocturia in older people.

OBJECTIVES: Desmopressin improves nocturia frequency; however, reports on its long-term efficacy and safety are few, and concerns regarding its effect on body composition exist. We thus investigated the efficacy and safety of long-term desmopressin administration and its effect on body composition. METHODS: This retrospective study, conducted at Chikugo City Hospital between August 2020 and December 2022, involved 133 men (mean age, 77.7 years) with nocturnal and persistent nocturia, who were administered an initial dose of 50 µg desmopressin. Efficacy endpoints included nocturnal urinary frequency, nocturnal urinary volume, hours of undisturbed sleep, nocturnal polyuria index, initial nocturnal urinary volume, and daily urinary frequency in a frequency-volume chart (3 days), before treatment and at 1, 4, 12, 24, and 52 weeks after desmopressin administration. Additionally, the effects of desmopressin on body composition were examined, including blood-brain natriuretic peptide and a chest radiography, before and 52 weeks after administration. RESULTS: Treatment improved most efficacy endpoint evaluation parameters. Around 87.6% of patients showed improved symptoms after 52 weeks compared with those before treatment (score ≤ 3). The blood-brain natriuretic peptide level rose; however, cardiothoracic ratio was unchanged. CONCLUSION: Long-term administration of desmopressin is thus effective and safe in older people with nocturnal polyuria, with little effect on body composition.

Autonomic nervous system dysregulation in children with monosymptomatic nocturnal enuresis.

AIM: To investigate the role of autonomic nervous system in subpopulations of children with enuresis. METHODS: We included 35 children with enuresis, divided in children with (17) and without nocturnal polyuria (18) and 43 healthy controls. For all participants hormones and neurotransmitters were measured. Patients and controls wore a sleep tracker device and children with enuresis underwent a 24 h blood pressure monitoring, nocturnal urine output measurement and uroflowmetry. RESULTS: Children with enuresis had lower than controls copeptin and aldosterone, with the latter being more prominent in patients without nocturnal polyuria. Dopamine was lower in patients without nocturnal polyuria compared with patients with nocturnal polyuria. Children without polyuria experienced episodes only during NREM sleep, whereas in children with polyuria episodes occurred in both REM and NREM sleep. Children with enuresis experienced a non-dipping phenomenon during sleep which was more prominent in the group without polyuria. CONCLUSION: In patients with nocturnal polyuria, nocturnal enuresis is associated with sympathetic hyperactivity which results in pressure polyuria and significantly lower systolic dipping during sleep. On the contrary, in children without nocturnal polyuria, it is mostly associated with bladder overactivity due to parasympathetic overstimulation as demonstrated by the NREM-related enuretic episodes and the lower aldosterone and dopamine levels.

Transient Diabetes Insipidus After Vasopressin Discontinuation.

Vasopressin infusion is commonly used in intensive care settings during states of advanced vasodilatory shock for its vasoconstrictive properties. Vasopressin also acts on renal tubular cell receptors in the collecting ducts of kidneys to allow for water reabsorption. The sudden discontinuation of vasopressin infusion can lead to the development of transient diabetes insipidus (DI) with classic findings of polyuria, dilute urine, and hypernatremia. We report the case of a 59-year-old male who underwent an emergent bedside cricothyrotomy procedure secondary to papillary carcinoma of the thyroid and subsequently developed septic shock requiring initiation of vasopressin infusion for hemodynamic support. He remained on vasopressin for five days before the infusion was discontinued after clinical improvement. Within 12 hours of vasopressin discontinuation, the patient developed polyuria (> 3 L/day urine output) with volumes as high as 1 L per hour. His serum sodium levels increased more than 10 mmol/L from 137 to 149 mmol/L. This case is unique from prior reports, as our patient was without any neurological or neurosurgical comorbidities that would predispose him to an organic central cause of DI. Furthermore, the patient's large-volume diuresis and serum abnormalities spontaneously self-improved within 24 hours without significant medical intervention. In conclusion, this case adds to a growing number of reports of transient DI following vasopressin withdrawal, demonstrating the need to formally recognize this occurrence as a potential consequence of vasopressin use in intensive care settings.

Copeptin Stimulation by Combined Intravenous Arginine and Oral LevoDopa/Carbidopa in Healthy Short Children and Children with the Polyuria-Polydipsia Syndrome.

INTRODUCTION: Stimulated copeptin may provide an alternative to water deprivation testing (WDT) in the evaluation of polyuria-polydipsia syndrome (PPS). Though best studied, arginine stimulation alone produces a modest copeptin response in children. We investigated the effectiveness of the arginine + LevoDopa/Carbidopa stimulation test (ALD-ST) for copeptin. METHODS: 47 healthy short children (controls), 10 children with primary polydipsia, and 10 children with AVP deficiency received arginine hydrochloride (500 mg/kg intravenously over 30 min) and Levodopa/carbidopa (10:1 ratio; 175 mg of l-Dopa/m2 BSA) orally. Serum copeptin was measured at 0, 60, 90, and 120 min. RESULTS: In controls, ALD-ST increased copeptin from a median of 7.0 pmol/L (IQR 5.0-10.0) to a peak of 44.0 pmol/L (IQR 21.4-181.0) between 60 and 120 min (p < 0.001). Copeptin peak was higher in subjects who experienced nausea or vomiting (57%) than in those who did not (131.0 pmol/L [IQR 42.5-193.8] vs. 22.7 pmol/L [IQR 16.0-33.7], p < 0.001). While subjects with primary polydipsia had similar baseline (8.5 pmol/L [IQR 8.0-11.0]) and stimulated (125.2 pmol/L [IQR 87.6-174.0]) copeptin levels as controls, subjects with AVP deficiency had lower baseline (2.5 pmol/L [IQR 2.0-3.1]) and peak levels (4.6 pmol/L [IQR 2.4-6.0]). A peak copeptin of ≥9.3 pmol/L best predicted absence of complete or partial AVP deficiency with a sensitivity of 100% and specificity of 80%. CONCLUSIONS: ALD-ST induced a robust peak copeptin in healthy short children and children with primary polydipsia. Nausea/vomiting, a side effect of ALD-ST, amplified the copeptin response. The ALD-ST may be a suitable initial screening test in children with PPS.

Factors related to nocturia-specific quality of life in renal transplantation patients.

OBJECTIVES: Patients following renal transplantation (RTX) may experience nocturia exacerbation due to polyuria and reduced bladder capacity, thereby impacting the specific quality of life (QOL) associated with nocturia. The present study aims to investigate factors associated with the deterioration of nocturia-specific QOL in RTX patients. METHODS: The study cohort comprised 59 consecutive patients who had undergone successful RTX. Nocturia-related QOL questionnaires (N-QOL) were employed to evaluate the specific QOL related to nocturia. The Bother/Concern and Sleep/Energy domains of the N-QOL were also assessed. The primary outcome measure was to explore factors related to the aggravation of nocturia-specific QOL in patients post-RTX. RESULTS: The mean nocturia frequency post-RTX was 1.3 ± 1.0. Univariate and multivariate analyses revealed a significant reduction in the Bother/Concern domain score associated with increased nocturia (p = .042). Aging significantly decreased the total N-QOL score and the Sleep/Energy domain score (p = .001 and .0002, respectively). Prolonged duration after RTX significantly reduced the scores of both the Sleep/Energy domain and the Bother/Concern domain (p = .018 and .037, respectively). However, the duration of dialysis prior to RTX was not significantly associated with the total score or subdomains of N-QOL. CONCLUSIONS: Nocturia-specific QOL affected not only the nocturia itself, but also aging and the prolonged duration after RTX. Thus, comprehensive approaches to the RTX patients were needed to improve the Nocturia-specific QOL in RTX patients.

Un mecanismo nefrogénico subyace a la poliuria inducida por dexmedetomidina: informe de un caso / Nephrogenic mechanism underlies dexmedetomidine-induced polyuria: A case report

La dexmedetomidina, agonista del adrenorreceptor α, se utiliza cada vez más como agente sedativo-hipnótico y analgésico, aunque su popularidad suscita preocupación acerca de los efectos secundarios de dicho fármaco.La bradicardia y la hipotensión son efectos adversos comunes, pero también existen diversos informes de gasto urinario excesivo, posiblemente debido a la secreción de vasopresina y a la permeabilidad de los conductos colectores.La poliuria se resuelve normalmente con la discontinuación del fármaco, no habiéndose reportado morbilidad significativa. La identificación temprana, la eliminación del agente y el tratamiento son imperativos para minimizar las complicaciones, principalmente natremia y síntomas neurológicos.Este informe de caso describe la poliuria relacionada con dexmedetomidina durante la anestesia general libre de opioides para cirugía mayor de cabeza y cuello. Nuestra hipótesis de etiología nefrogénica se ve reforzada por los datos analíticos obtenidos. También describimos cómo abordar la poliuria intraoperatoria. (AU)

Dexmedetomidine's α-adrenoreceptor agonism has been gaining popularity in the anesthetic room as a sedative-hypnotic and analgesic agent, and with extensive perioperative use rising concern about side effects is necessary.Bradycardia and hypotension are common but excessive urine output is increasingly reported, suggested mechanisms being vasopressin secretion and increasing permeability of the collecting ducts.Polyuria usually resolves with discontinuation of the drug and significant morbidity has not been reported. Early identification, removal of agent and treatment are imperative to minimize complications, mainly associated with natremia levels and neurological symptoms.This case report describes a dexmedetomidine-related polyuric syndrome during opioid-free general anesthesia for major head and neck surgery. A nephrogenic mechanism for the clinical effect is proposed and reinforced by analytical data obtained. An intra-operative polyuria approach is also delineated. (AU)

Avian Diabetes Mellitus: A Review.

Diabetes mellitus (DM) is an uncommon, poorly documented metabolic disorder of birds. Extrapolating knowledge from DM in mammals is challenging because of marked differences in avian physiology and metabolism. A literature review from December 1991 to January 2022 identified 14 publications covering 16 diabetic birds, 63% (10/16) of which belonged to the order Psittaciformes with Ara as the predominant genus. No sex predilection was noted, but males generally presented at a younger age. Commonly reported clinical signs included polyuria 94% (15/16), polydipsia 88% (14/16), weight loss 75% (12/16), lethargy 63% (10/16), and polyphagia 38% (6/16). Diagnosis of DM was based on the presence of clinical signs and persistent hyperglycemia 100% (16/16), often with glucosuria 93% (13/14), response to insulin therapy 80% (8/10), and pancreatic pathology 90% (9/10). Specific treatment for DM was initiated in 14 patients, but blood glucose regulation for 6 months or longer was only achieved in 6 birds. Five of the regulated birds were managed with injectable long-acting insulin and 1 with oral glipizide combined with dietary modifications. However, glipizide yielded poor results in other cases, likely attributable to a lack of functional beta cells. Three diabetic birds progressed to remission. Treatment proved unsuccessful for 7 patients with a mean survival time of 36 days from diagnosis. One patient was lost to follow-up, and 2 were euthanized immediately following diagnosis. Histological examination of the pancreas frequently (90%, 9/10) revealed abnormalities including atrophy, fibrosis, and vacuolization of the endocrine islets with or without lymphoplasmacytic pancreatitis. Comorbidities, including hemosiderosis and infection, were common. This review suggests that birds diagnosed with DM are primarily affected by a type I diabetes as observed in dogs and humans. In contrast to mammalian species, avian DM is often associated with underlying disease and a complete clinical workup is essential to diagnose and address secondary disease conditions prior to initiating long-term insulin therapy.