Diagnosis and management of diabetes insipidus for the internist: an update

Causal role of immune cells in diabetic nephropathy: a bidirectional Mendelian randomization study

Background

Diabetic nephropathy (DN) stands as a pervasive chronic renal disease worldwide, emerging as the leading cause of renal failure in end-stage renal disease. Our objective is to pinpoint potential immune biomarkers and evaluate the causal effects of prospective therapeutic targets in the context of DN.

Methods

We employed Mendelian randomization (MR) analysis to examine the causal associations between 731 immune cell signatures and the risk of DN. Various analytical methods, including inverse-variance weighted (IVW), MR-Egger, weighted median, simple mode, and weighted mode, were employed for the analysis. The primary analytical approach utilized was the inverse-variance weighted (IVW) method. To ensure the reliability of our findings, we conducted comprehensive sensitivity analyses to assess the robustness, heterogeneity, and presence of horizontal pleiotropy in the results. Statistical powers were also calculated. Ultimately, a reverse Mendelian randomization (MR) analysis was conducted to assess the potential for reverse causation.

Results

After Benjamini & Hochberg (BH) correction, four immunophenotypes were identified to be significantly associated with DN risk: HLA DR on Dendritic Cell (OR=1.4460, 95% CI = 1.2904~1.6205, P=2.18×10-10, P.adjusted= 1.6×10-7), HLA DR on CD14+ CD16- monocyte (OR=1.2396, 95% CI=1.1315~1.3580, P=3.93×10-6, P.adjusted = 0.00143). HLA DR on CD14+ monocyte (OR=1.2411, 95% CI=1.12957~1.3637, P=6.97×10-6, P.adjusted=0.0016), HLA DR on plasmacytoid Dendritic Cell (OR=1.2733, 95% CI= 1.1273~1.4382, P= 0.0001, P.adjusted = 0.0183). Significant heterogeneity of instrumental variables was found in the four exposures, and significant horizontal pleiotropy was only found in HLA DR on Dendritic Cell. The bidirectional effects between the immune cells and DN were not supported.

Conclusion

Our research illustrated the intimate association between immune cells and DN, which may contribute to a deeper understanding of the intricate mechanisms underlying DN and aid in the identification of novel intervention target pathways.

Desmopressin dose requirements in patients with permanent arginine vasopressin deficiency: a tertiary center experience

PURPOSE

The desmopressin daily dose requirement is highly variable among patients with arginine vasopressin (AVP) deficiency (i.e. central diabetes insipidus) and few studies to date have evaluated this topic, with often inconclusive results. The aim of our study was to identify clinical and biochemical predictors of such dose requirements in a cohort of patients with a confirmed diagnosis of permanent AVP deficiency who have good and stable control under substitutive treatment.

METHODS

We retrospectively analyzed data of all patients with permanent AVP deficiency undergoing regular follow-up at our Division. Inclusion criteria were the presence of stable disease under therapy for at least 12 months and in good biochemical and clinical control. Patients with AVP deficiency who lacked intact thirst or had a disease duration of less than 12 months were excluded from the analysis.

RESULTS

Out of the 132 patients initially screened, 96 patients (M/F 44/52; age 51 [37-63] years) met the inclusion criteria. Patients on nasal spray therapy (n = 8) had a significantly longer disease duration (p = 0.002) than patients treated with oral lyophilizate (n = 88). In the bivariate analysis, considering only patients treated with the sublingual formulation, the drug dose was correlated positively with estimated glomerular filtration rate (eGFR) and weight (r = 0.410, p < 0.001; r = 0.224, p = 0.036, respectively) and negatively with age (r = - 0.433, p < 0.001). In the multivariate regression analysis taking into account age, weight, and eGFR, only age emerged as a significant predictor of the required sublingual desmopressin dose (β = - 1.426, p = 0.044).

CONCLUSION

Our data suggest that patient age appears to be the primary factor associated with the daily sublingual desmopressin dose required to achieve adequate clinical and biochemical control in patients with permanent AVP deficiency.

Deciphering the Biological Aging Impact on Alveolar Bone Loss: Insights From α-Klotho and Renal Function Dynamics

Alveolar bone loss is generally considered a chronological age-related disease. As biological aging process is not absolutely determined by increasing age, whether alveolar bone loss is associated with increasing chronological age or biological aging remains unclear. Accurately distinguishing whether alveolar bone loss is chronological age-related or biological aging-related is critical for selecting appropriate clinical treatments. This study aimed to identify the relationship between alveolar bone loss and body aging. In total, 3 635 participants from the National Health and Nutrition Examination Survey and 71 living kidney transplant recipients from Gene Expression Omnibus Datasets were enrolled. Multivariate regression analysis, smooth curve fittings, and generalized additive models were used to explore the association among alveolar bone loss, age, serum α-Klotho level, renal function markers, as well as between preoperative creatinine and renal cortex-related α-Klotho gene expression level. Meanwhile, a 2-sample Mendelian randomization (MR) study was conducted to assess the causal relationship between α-Klotho and periodontal disease (4 376 individuals vs 361 194 individuals). As a biological aging-related indicator, the α-Klotho level was negatively correlated with impaired renal function and alveolar bone loss. Correspondingly, accompanied by decreasing renal function, it was manifested with a downregulated expression level of α-Klotho in the renal cortex and aggravated alveolar bone loss. The MR analysis further identified the negative association between higher genetically predicted α-Klotho concentrations with alveolar bone loss susceptibility using the IVW (odds ratio [OR] = 0.999, p = .005). However, an inversely U-shaped association was observed between chronological age and alveolar bone loss, which is especially stable in men (the optimal cutoff values were both 62 years old). For men above 62 years old, increasing age is converted to protective factor and is accompanied by alleviated alveolar bone loss. Alveolar bone loss that is directly associated with decreased renal function and α-Klotho level was related to biological aging rather than chronological age. The renal-alveolar bone axis could provide a new sight of clinical therapy in alveolar bone loss.

Evaluation of postoperative fluctuations in plasma sodium concentration and triphasic response after pediatric craniopharyngioma resection: A French cohort study

INTRODUCTION

Disturbances in plasma sodium levels are a major complication following recent resections of craniopharyngiomas in children. They must be properly managed to avoid neurological sequelae. We aimed to describe the variations and characteristics of postoperative natremia in children who had undergone a first craniopharyngioma resection with a particular focus on the frequency of triphasic syndrome in these patients.

METHODS

Paediatric patients with craniopharyngiomas who underwent a first surgical resection in the neurosurgery department of the Hôpital Femme Mère Enfant (Lyon, France) between January 2010 and September 2021 were included in the present study and the medical records were analysed retrospectively.

RESULTS

A total of 26 patients were included. Of these, 17 (65.4%) had a postoperative course characterised by the occurrence of both initial diabetes insipidus (DI) and hyponatremia a few days later. Eight patients (30.8%) presented then with isolated and persistent DI. Patients with the triphasic syndrome had a significantly higher grade of Puget classification on MRI (1 and 2), compared to the other patients.

CONCLUSION

Dysnatremia is common after craniopharyngioma resections in children. This immediate postoperative complication is particularly difficult to manage and requires rapid diagnosis and prompt initiation of medical treatment to minimize fluctuations in sodium levels and avoid neurological sequelae.

Central Diabetes Insipidus in Children as a Diagnostic Challenge

Central diabetes insipidus (CDI) is a disorder in the pediatric population resulting from antidiuretic hormone deficiency. The excessive production of dilute urine characterizes it and manifests with polyuria, nocturia, and polydipsia. The diagnostics of CDI is often challenging, especially concerning the underlying condition of the disease. This article highlights the diverse clinical presentation of children with CDI and diagnostic difficulties among patients with polyuria and polydipsia. The article also reviews the etiology, symptoms, diagnostic workup, and management of CDI. We present 4 pediatric patients (aged 3-13.5 years) diagnosed with CDI of different etiology: 1 due to septo-optic dysplasia/optic nerve hypoplasia and 3 due to acquired processes such as Langerhans cell histiocytosis and germ cell tumor in 2 patients. Central diabetes insipidus was the first manifestation of a tumor or granuloma in all presented patients with acquired pathology. The patients sometimes need long-term follow-up to establish the proper final diagnosis.

Glucose Oxidase Coupling with Pistol-Like DNAzyme Based Colorimetric Assay for Sensitive Glucose Detection in Tears and Saliva

Non-invasive monitoring of glucose levels in tears and saliva is crucial for diagnosing and predicting various illnesses, such as diabetic nephropathy. However, the capability of the current glucose detection methods to identify small amounts of glucose with a high sensitivity remains a significant obstacle. This study proposes a simple, visual technique for sensitively detecting glucose levels from tears and saliva using glucose oxidase (GOx) to catalyze glucose and pistol-like DNAzyme (PLDz) to enhance the signal. In particular, the β-D-glucose present in the samples serves as the initial molecule that GOx identifies and catalyzes to generate gluconic acid and hydrogen peroxide (H2O2). The H2O2 induces the self-cleavage of PLDz, activating the "part b" sequence. This activation initiates catalytic hairpin assembly (CHA) and releases the DNAzyme section in the H1 probe. The DNAzyme acts as a peroxidase analog, facilitating the catalysis of the 3,3',5,5'-tetramethylbenzidine (TMB)-hydrogen peroxide (H2O2) system and resulting in color changes. The proposed method exhibits a broad detection range of six orders of magnitude and a low limit of 0.32 μM for glucose detection. Furthermore, the proposed method was highly effective in detecting glucose in saliva and tears, suggesting that it could potentially diagnose hyperglycemia-related disorders in clinical environments.

Arginine vasopressin deficiency: diagnosis, management and the relevance of oxytocin deficiency

Polyuria-polydipsia syndrome can be caused by central diabetes insipidus, nephrogenic diabetes insipidus or primary polydipsia. To avoid confusion with diabetes mellitus, the name 'central diabetes insipidus' was changed in 2022 to arginine vasopressin (AVP) deficiency and 'nephrogenic diabetes insipidus' was renamed as AVP resistance. To differentiate the three entities, various osmotic and non-osmotic copeptin-based stimulation tests have been introduced in the past decade. The hypertonic saline test plus plasma copeptin measurement emerged as the test with highest diagnostic accuracy, replacing the water deprivation test as the gold standard in differential diagnosis of the polyuria-polydipsia syndrome. The mainstay of treatment for AVP deficiency is AVP replacement with desmopressin, a synthetic analogue of AVP specific for AVP receptor 2 (AVPR2), which usually leads to rapid improvements in polyuria and polydipsia. The main adverse effect of desmopressin is dilutional hyponatraemia, which can be reduced by regularly performing the so-called desmopressin escape method. Evidence from the past few years suggests an additional oxytocin deficiency in patients with AVP deficiency. This potential deficiency should be further evaluated in future studies, including feasible provocation tests for clinical practice and interventional trials with oxytocin substitution.

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.

Living-donor lobar lung transplantation for pulmonary Langerhans cell histiocytosis complicated by extensive thrombi in central pulmonary arteries

BACKGROUND

Pulmonary Langerhans cell histiocytosis (PLCH) is a rare disorder characterized by the proliferation of Langerhans cells along the small airways, which causes nodular and cystic changes in the lung parenchyma. Lung transplantation can be a life-saving option for patients with severe respiratory failure or pulmonary hypertension. Herein, we present a case of successful lung transplantation in a patient with PLCH who developed unusually large thrombi in the central pulmonary artery.

CASE PRESENTATION

A 47-year-old woman with 16-year history of PLCH with rapidly developing respiratory failure was admitted to our hospital for the evaluation of a lung transplant. Enhanced computed tomography revealed large thrombi in dilated central pulmonary arteries. Right heart catheterization revealed severe pulmonary hypertension, with a mean pulmonary artery pressure of 48 mmHg. The thrombi shrank markedly after 3 months of anticoagulation therapy. However, the respiratory status of the patient did not improve. We performed bilateral living-donor lobar lung transplantation with thrombectomy under extracorporeal membrane oxygenation for the remaining thrombi in the main pulmonary arteries. The dilated main pulmonary arteries of the recipient required direct plication for size mismatch. The patient survived in good condition for more than 2 years with no recurrence of thrombosis.

CONCLUSION

Preoperative anticoagulation therapy for massive thrombi in the pulmonary arteries was effective and led to safe lung transplantation.

Myopia and Rate of Peripapillary Retinal Nerve Fiber Layer Thickness in Diabetic Patients Without Retinopathy: A 2-Year Longitudinal Study

PURPOSE

The aim of this study was to investigate the association between myopia and longitudinal changes in peripapillary retinal nerve fiber layer (pRNFL) thickness in type 2 diabetic patients without diabetic retinopathy (DR).

METHODS

A total of 1069 participants with a median follow-up time of 1.9 years were included in this study. The participants were categorized into four groups based on the presence of myopia (≤ -0.5 diopter [D]) and diabetes without DR, including a control group (n = 412), diabetes group (n = 416), myopia group (n = 115), and diabetes + myopia group (n = 126). Peripapillary average and sectoral RNFL measurements were obtained using 6 × 6 mm swept-source optical coherence tomography (SS-OCT) scans centered at the optic disc. The change rate of pRNFL, adjusted for age and sex, was calculated and compared among the four groups to investigate the impact of myopia and diabetes.

RESULTS

The baseline estimated pRNFL thickness after adjustment for covariates was 113.7 μm, 116.2 μm, 108.0 μm, and 105.6 μm in the control, diabetes, myopia, and diabetes + myopia group, respectively (diabetes > control > myopia = diabetes + myopia, p < 0.001). The respective average pRNFL loss in the four groups was -0.48 μm/year, -1.11 μm/year, -1.23 μm/year, and -2.62 μm/year (all p < 0.01). The diabetes + myopia group exhibited a greater rate of average pRNFL reduction compared to the other groups (all p < 0.001). Multivariate analysis using a linear mixed-effects model showed that age, diabetes, axial length (AL), and baseline pRNFL thickness were significantly associated with the rate of average pRNFL reduction.

CONCLUSIONS

The diabetes group showed a faster rate of average pRNFL thickness reduction compared to healthy controls, regardless of the presence of myopia. The average pRNFL thickness decreased more rapidly when diabetes and myopia were present simultaneously than in the individual diabetes or myopia group. Both diabetes and myopia were associated with accelerated pRNFL loss.

Position statement on the diagnosis and management of congenital pituitary deficiency in adults: The French National Diagnosis and Treatment Protocol (NDTP)

Pituitary deficiency, or hypopituitarism, is a rare chronic disease. It is defined by insufficient synthesis of one or more pituitary hormones (growth hormone, TSH, ACTH, LH-FSH, prolactin), whether or not associated with arginine vasopressin deficiency (formerly known as diabetes insipidus). In adult patients, it is usually acquired (notably during childhood), but can also be congenital, due to abnormal pituitary development. The present study focuses on congenital pituitary deficiency in adults, from diagnosis to follow-up, including special situations such as pregnancy or the elderly. The clinical presentation is highly variable, ranging from isolated deficit to multiple deficits, which may be part of a syndromic form or not. Diagnosis is based on a combination of clinical, biological (assessment of all hormonal axes), radiological (brain and hypothalamic-pituitary MRI) and genetic factors. Treatment consists in hormonal replacement therapy, adapted according to the period of life and the deficits, which may be progressive. Comorbidities, risk of complications and acute decompensation, and the impact on fertility and quality of life all require adaptative multidisciplinary care and long-term monitoring.

Correlation of ChREBP Gene Methylation with Pathological Characteristics of Type 2 Diabetes Mellitus

The objective of this study is to investigate the expression of the carbohydrate response element binding protein (ChREBP) gene in type 2 diabetes mellitus (T2DM) and its correlation with pathological features. For obtaining and exploring the pathological features in patients, sixty T2DM patients (the research group) and thirty healthy controls (the control group) presented to our hospital between January 2019 and June 2019 were selected as the research participants. After DNA extraction from peripheral blood mononuclear cells (PBMCs) and modification of target gene methylation with bisulfite, differences in methylation were verified, and the correlation of ChREBP methylation level with T2DM pathological features and single nucleotide polymorphism (SNP) typing was discussed. According to the prediction results of UCSC Genome Browser Home, there were two CpG islands in the promoter region of the ChREBP gene, and the first exon was selected for research. The ChREBP methylation rate was statistically higher in the research group versus the control group (P < 0.05). Age, FPG, TC, and TG were confirmed by the multiple linear regression analysis to be correlated with the ChREBP methylation rate (P < 0.05). Finally, there was no difference in ChREBP methylation level between CT- and CC-type patients at rs17145750 and rs1051921 loci (P > 0.05). Peripheral blood ChREBP methylation is elevated in T2DM patients and is closely related to age, blood glucose, and blood-lipid level, which is expected to be a new direction for future T2DM diagnosis and treatment.

Sertraline Hydrochloride Overdose Resulting in Diabetes Insipidus: A Case Report

Sertraline hydrochloride belongs to the selective serotonin reuptake inhibitor class of antidepressants, which can cause respiratory depression, hypotension, malignant vomiting, liver function impairment, and other symptoms when taken in excess. To our knowledge, reports of sertraline hydrochloride overdose causing diabetes insipidus in patients are rare. This report describes a unique case of a 17-year-old female patient who developed diabetes insipidus after a one-time oral intake of 20 sertraline hydrochloride tablets (50 mg/tablet) during the later course of treatment. Her symptoms were effectively relieved after treatment with pituitrin.

Association between pulp and periapical disease with type 2 diabetes: A bidirectional Mendelian randomization

AIM

This current Mendelian randomization (MR) study aims to comprehensively explore the potential bidirectional link between pulp and periapical disease (PAP) with type 2 diabetes mellitus (T2DM).

METHODOLOGY

Summary level data of European-based population genome-wide association studies (GWASs) were employed to undertake this MR study. With the selection of single nucleotide polymorphisms (SNPs) as the instrumental variable, the radial inverse-variance weighted (radial IVW) method with modified second-order weights was applied as the primary method. Additionally, a range of sensitivity analyses were conducted to investigate pleiotropy. Results from different sources of outcome were pooled by meta-analysis with the fixed model.

RESULTS

The results of this MR analysis did not suggest a significant impact of pulp and periapical disease on type 2 diabetes (combined OR = 1.04, 95% CI: 1.00-1.07, p = .033) and vice versa (OR = 1.04, 95% CI: 0.96-1.14, p = .329). No significant pleiotropy was detected in the final model after the removal of outliers, demonstrating the reliability of the results in our primary analysis.

CONCLUSIONS

With the limitations inherent in the present MR study, there is no significant evidence in either direction to suggest a causal association between pulp and periapical disease and type 2 diabetes mellitus.

Simplified drug efficacy evaluation system for vasopressin neurodegenerative disease using mouse disease-specific induced pluripotent stem cells

Familial neurohypophyseal diabetes insipidus (FNDI) is a degenerative disorder in which vasopressin-secreting neurons degenerate over time due to the production of mutant proteins. We have demonstrated therapeutic effects of chemical chaperones in an FNDI mouse model, but the complexity and length of this evaluation were problematic. In this study, we established disease-specific mouse induced pluripotent stem cells (iPSCs) from FNDI-model mice and differentiated vasopressin neurons that produced mutant proteins. Fluorescence immunostaining showed that chemical chaperones appeared to protect vasopressin neurons generated from iPSCs derived from FNDI-model mice. Although KCL stimulation released vasopressin hormone from vasopressin neurons generated from FNDI-derived iPSCs, vasopressin hormone levels did not differ significantly between baseline and chaperone-added culture. Semi-quantification of vasopressin carrier protein and mutant protein volumes in vasopressin neurons confirmed that chaperones exerted a therapeutic effect. This research provides fundamental technology for creating in vitro disease models using human iPSCs and can be applied to therapeutic evaluation of various degenerative diseases that produce abnormal proteins.

Status of waste disposal of sharps outside medical institutions for patients with diabetes: A systematic review

OBJECTIVES

As the number of people with diabetes increases, so does the amount of household-generated sharp waste, and incorrect sharp disposal methods can expose the public to needle stick injuries This systematic study assesses the relevant factors and current situation of the disposal of sharp waste in diabetes patients.

METHODS

In this review, our study comprehensively searched PubMed, MEDLINE, Cochrane Library, EMBASE, Web of Science, and China Biomedical, Wanfang, and CNKI for the concepts of "sharps waste disposal" and "diabetes".

RESULT

In 12 identified articles, there are 4155 patients with diabetes. The findings highlight that diabetic patients have a positive attitude towards sharps waste disposal, but lack knowledge and practice of sharps waste disposal, and need to take appropriate measures to improve the rate of proper waste disposal before and during use. Patients with longer duration of diabetes are more likely to engage in inappropriate sharps disposal behaviors.

CONCLUSIONS

The findings emphasize that the majority of diabetic patients are unable to handle sharps safely, so more research is needed to find factors associated with sharps waste disposal in diabetic patients and to focus on sharps waste disposal behaviors in patients with longer duration of disease in future clinical practice.

TRIAL REGISTRATION

PROSPERO ID. The review was registered on PROSPERO (registration number: CRD42023427592) https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023427592.

Arginine or Hypertonic Saline-Stimulated Copeptin to Diagnose AVP Deficiency

BACKGROUND

Distinguishing between arginine vasopressin (AVP) deficiency and primary polydipsia is challenging. Hypertonic saline-stimulated copeptin has been used to diagnose AVP deficiency with high accuracy but requires close sodium monitoring. Arginine-stimulated copeptin has shown similar diagnostic accuracy but with a simpler test protocol. However, data are lacking from a head-to-head comparison between arginine-stimulated copeptin and hypertonic saline-stimulated copeptin in the diagnosis of AVP deficiency.

METHODS

In this international, noninferiority trial, we assigned adult patients with polydipsia and hypotonic polyuria or a known diagnosis of AVP deficiency to undergo diagnostic evaluation with hypertonic-saline stimulation on one day and with arginine stimulation on another day. Two endocrinologists independently made the final diagnosis of AVP deficiency or primary polydipsia with use of clinical information, treatment response, and the hypertonic-saline test results. The primary outcome was the overall diagnostic accuracy according to prespecified copeptin cutoff values of 3.8 pmol per liter after 60 minutes for arginine and 4.9 pmol per liter once the sodium level was more than 149 mmol per liter for hypertonic saline.

RESULTS

Of the 158 patients who underwent the two tests, 69 (44%) received the diagnosis of AVP deficiency and 89 (56%) received the diagnosis of primary polydipsia. The diagnostic accuracy was 74.4% (95% confidence interval [CI], 67.0 to 80.6) for arginine-stimulated copeptin and 95.6% (95% CI, 91.1 to 97.8) for hypertonic saline-stimulated copeptin (estimated difference, -21.2 percentage points; 95% CI, -28.7 to -14.3). Adverse events were generally mild with the two tests. A total of 72% of the patients preferred testing with arginine as compared with hypertonic saline. Arginine-stimulated copeptin at a value of 3.0 pmol per liter or less led to a diagnosis of AVP deficiency with a specificity of 90.9% (95% CI, 81.7 to 95.7), whereas levels of more than 5.2 pmol per liter led to a diagnosis of primary polydipsia with a specificity of 91.4% (95% CI, 83.7 to 95.6).

CONCLUSIONS

Among adult patients with polyuria polydipsia syndrome, AVP deficiency was more accurately diagnosed with hypertonic saline-stimulated copeptin than with arginine-stimulated copeptin. (Funded by the Swiss National Science Foundation; CARGOx ClinicalTrials.gov number, NCT03572166.).

Clinical applications of smart wearable sensors

Smart wearable sensors are electronic devices worn on the body that collect, process, and transmit various physiological data. Compared to traditional devices, their advantages in terms of portability and comfort have made them increasingly important in the medical field. This review takes a unique clinical physician's standpoint, diverging from conventional sensor-type-based classifications, and provides a comprehensive overview of the diverse clinical applications of wearable sensors in recent years. In this review, we categorize these applications according to different diseases, encompassing skin diseases and injuries, cardiovascular diseases, abnormal human motion, as well as endocrine and metabolic disorders. Additionally, we discuss the challenges and perspectives hindering the development of sensors for clinical use, emphasizing the critical need for interdisciplinary collaboration between medical and engineering professionals. Overall, this review would serve as an important reference for the future direction of sensor devices in clinical use.

Neurogenic diabetes insipidus in a critical patient with COVID-19 pneumonia in treatment with extracorporeal membrane oxygenation: a case report

The following case report analyses a patient with extracorporeal membrane oxygenation (ECMO), who suffered from a severe Acute Respiratory Distress Syndrome (ARDS) due to COVID-19 pneumonia. ARDS is defined as a diffuse and inflammatory injury of the lungs; classifying this as severe when the ratio of arterial oxygen tension to a fraction of inspired oxygen (PaO2/FiO2) is equal to or lower than 100 mmHg. To decide if the patient was suitable for the use of ECMO therapy, the ELSO criteria were used; and in this case, the patient matched with the criteria of hypoxemic respiratory failure (with a PaO2/FiO2 < 80 mmHg) after optimal medical management, including, in the absence of contraindications, a trial of prone positioning. During hospitalization, the patient presented a Central Diabetes Insipidus (CDI), probably explained by the damage hypoxia generated on the central nervous system. There are few reports of this complication produced by COVID-19. The case is about a 39-year-old woman, who started with ECMO 6 days after the beginning of Invasive Mechanical Ventilation (IMV), because of a severe ARDS. On the fifth day of ECMO, the patient started with a polyuria of 7 L in 24 h. A series of paraclinical studies were made, but no evidence of central nervous system lesions was found. After treatment with desmopressin was initiated and the ARDS was solved, polyuria stopped; with this, CDI was diagnosed. There are many complications secondary to the evolution of COVID-19 infection, and some of them are not yet well explained.

Arginine-Stimulated Copeptin-Based Diagnosis of Central Diabetes Insipidus in Children and Adolescents

INTRODUCTION

Diagnosis of central diabetes insipidus (CDI) remains challenging. Water deprivation testing and hypertonic saline infusion, as established diagnostic tests, are mentally and physically demanding for patients. Arginine-stimulated copeptin has been shown as a putative parameter for the differential diagnosis of CDI in adults.

METHODS

In this single-centre retrospective study, we identified paediatric patients with suspected pituitary disorders who underwent standard arginine testing. Patients with CDI, matched controls, and primary polydipsia (PP) were identified. Diagnoses were confirmed retrospectively using comprehensive clinical and diagnostic characteristics. Serum copeptin concentrations were measured using a commercially available automated immunofluorescence assay (B.R.A.H.M.S Copeptin-proAVP KRYPTOR®) in samples stored for a median of 4.6 years (1.3-10.84) and collected before and 60 min after arginine infusion. Cut-off analyses were performed using ROC curves.

RESULTS

Serum samples from 32 patients with CDI, 32 matched controls, and 5 patients with PP (n = 69; 51 males, 18 females) were available for analysis. Median copeptin concentrations increased from 4.47 pmol/L (interquartile range [IQR]: 3.47-8.36) to 6.96 pmol/L (IQR: 4.51-12.89; p < 0.001) in controls, from 1.46 pmol/L (IQR: 1.21-2.12) to 1.44 (IQR: 1.10-1.87; p = 0.645, ns) in CDI, and from 4.40 pmol/L (3.95-6.33) to 9.58 pmol/L (8.19-11.42; p < 0.001) in PP. The published cut-off value of 3.8 pmol/L revealed a sensitivity of 100% and a specificity of 86.5% in confirming CDI.

CONCLUSION

Our results suggest that arginine-stimulated serum copeptin concentrations are a sensitive and specific diagnostic tool for CDI in paediatric patients, which may replace and simplify the conventional diagnostic pathway of water deprivation testing and hypertonic saline infusion.

Association between living environmental quality and risk of arthritis in middle-aged and older adults: a national study in China

Background

The association between combined environmental factors and the risk of arthritis is still scarcely studied. The present study performed cross-sectional and cohort studies to explore the association between risk score of living environment quality and the risk of arthritis in middle-aged and older adults in China.

Methods

The study was based on China Health and Retirement Longitudinal Study (CHARLS), and it recruited 17,218 participants in the cross-sectional study and 11,242 participants in the seven-year follow-up study. The living environment quality was measured by household fuel types, household water sources, room temperature, residence types, and ambient concentration of PM2.5. Logistic regression and Cox proportional hazard regression models were utilized to examine the association between the living environment quality and the risk of arthritis. Competing risk models and stratified analyses were applied to further verify our results.

Results

Compared with individuals in the suitable environment group, people who lived in moderate (OR:1.28, 95%CI: 1.14-1.43) and unfavorable environments (OR:1.49, 95%CI:1.31-1.70) showed higher risks of arthritis when considering the multiple living environmental factors (P for trend <0.001) in the cross-sectional analysis. In the follow-up study, similar results (P for trend = 0.021), moderate environment group (HR:1.26, 95%CI:1.01-1.56) and unfavorable environment group (HR: 1.36, 95%CI: 1.07-1.74), were founded.

Conclusion

Inferior living environment might promote the development of arthritis. It is necessary for the public, especially old people, to improve the living environment, which may be the key to the primary prevention of arthritis.

The role of copeptin in kidney disease

Copeptin is a 39-amino acid glycopeptide that is secreted equimolecularly with arginine-vasopressin (AVP) from the prepro-hormone AVP in the posterior pituitary. While AVP is a very unstable molecule and is accompanied by significant technical troubles in its quantification, copeptin is a stable and easily quantifiable molecule. For this reason, circulating copeptin is currently used as a surrogate for AVP in different pathological conditions, including renal diseases. In recent years it has been shown that copeptin is associated with an increased risk of developing chronic kidney disease in the general population. In addition, copeptin has also been associated with multiple renal diseases with relevant clinical consequences and potential therapeutic implications. In the present review, we update and summarize the clinical significance of copeptin as a surrogate marker for AVP concentrations in different kidney diseases, as well as in renal replacement therapy (hemodialysis and peritoneal dialysis) and renal transplantation.

New developments and concepts in the diagnosis and management of diabetes insipidus (AVP-deficiency and resistance)

Diabetes insipidus (DI) is a disorder characterised by the excretion of large amounts of hypotonic urine, with a prevalence of 1 per 25,000 population. Central DI (CDI), better now referred to as arginine vasopressin (AVP)-deficiency, is the most common form of DI resulting from deficiency of the hormone AVP from the pituitary. The less common nephrogenic DI (NDI) or AVP-resistance develops secondary to AVP resistance in the kidneys. The majority of causes of DI are acquired, with CDI developing when more than 80% of AVP-secreting neurons are damaged. Inherited/familial CDI causes account for approximately 1% of cases. Although the pathogenesis of NDI is unclear, more than 280 disease-causing mutations affecting the AVP2 protein or AVP V2 receptor, as well as in aquaporin 2 (AQP2), have been described. Although the cAMP/protein kinase A pathway remains the major regulatory pathway of AVP/AQP2 action, in vitro data have also revealed additional cAMP independent pathways of NDI pathogenesis. Diagnosing partial forms of DI, and distinguishing them from primary polydipsia, can be challenging, previously necessitating the use of the water deprivation test. However, measurements of circulating copeptin levels, especially after stimulation, are increasingly replacing the classical tests in clinical practice because of their ease of use and high sensitivity and specificity. The treatment of CDI relies on desmopressin administration, whereas NDI requires the management of any underlying diseases, removal of offending drugs and, in some cases, administration of diuretics. A better understanding of the pathophysiology of DI has led to novel evolving therapeutic agents that are under clinical trial.

Mechanistic insights into the primary and secondary alterations of renal ion and water transport in the distal nephron

The kidneys, by equilibrating the outputs to the inputs, are essential for maintaining the constant volume, pH, and electrolyte composition of the internal milieu. Inability to do so, either because of internal kidney dysfunction (primary alteration) or because of some external factors (secondary alteration), leads to pathologies of varying severity, leading to modification of these parameters and affecting the functions of other organs. Alterations of the functions of the collecting duct (CD), the most distal part of the nephron, have been extensively studied and have led to a better diagnosis, better management of the related diseases, and the development of therapeutic tools. Thus, dysfunctions of principal cell-specific transporters such as ENaC or AQP2 or its receptors (mineralocorticoid or vasopressin receptors) caused by mutations or by compounds present in the environment (lithium, antibiotics, etc.) have been demonstrated in a variety of syndromes (Liddle, pseudohypoaldosteronism type-1, diabetes insipidus, etc.) affecting salt, potassium, and water balance. In parallel, studies on specific transporters (H+ -ATPase, anion exchanger 1) in intercalated cells have revealed the mechanisms of related tubulopathies like distal renal distal tubular acidosis or Sjögren syndrome. In this review, we will recapitulate the mechanisms of most of the primary and secondary alteration of the ion transport system of the CD to provide a better understanding of these diseases and highlight how a targeted perturbation may affect many different pathways due to the strong crosstalk and entanglements between the different actors (transporters, cell types).

Correlation between lipoprotein(a), albuminuria, myostatin and sarcopenia in elderly patients with type 2 diabetes

AIM

To investigate the relationship of the lipoprotein(a), albuminuria, myostatin with sarcopenia in elderly patients with type 2 diabetes (T2D).

METHODS

A total of 461 elderly patients with T2D who were admitted to our hospital were selected as the research subjects. There were 34 cases in line with Asian sarcopenia diagnosis (group A), and 427 patients had no such symptoms as the control group (group C). The levels of lipoprotein(a), albuminuria, myostatin in each group were compared, and the effect factors of muscle loss in elderly patients with T2D were analyzed by univariate/multivariate logistic regression.

RESULTS

The incidence of sarcopenia in 461 elderly patients with T2D in this study was 7.37 % (34/461). However, the levels of appendicular skeletal muscle mass index (ASMI, kg/m²), albumin and epidermal growth factor receptor (eGFR) in group A were lower than those in group C (P < 0.05). The levels of lipoprotein(a), albuminuria, myostatin in group A were higher those in group C (P < 0.05). Additionally, group A had a higher morbidity in diabetic retinopathy and neuropathy. Univariate logistic regression analysis revealed that the risk factors of muscle loss are ASMI, lipoprotein(a), albuminuria, myostatin, diabetic retinopathy and neuropathy. Multivariate Logistic regression analysis showed that the risk factors of muscle loss in elderly patients with T2D were lipoprotein(a), albuminuria, myostatin and diabetic neuropathy.

CONCLUSION

The lipoprotein(a), albuminuria, myostatin and diabetic neuropathy are closely related to the occurrence and development of muscle loss in elderly patients with T2D.

Machine learning-based algorithm as an innovative approach for the differentiation between diabetes insipidus and primary polydipsia in clinical practice

OBJECTIVE

Differentiation between central diabetes insipidus (cDI) and primary polydipsia (PP) remains challenging in clinical practice. Although the hypertonic saline infusion test led to high diagnostic accuracy, it is a laborious test requiring close monitoring of plasma sodium levels. As such, we leverage machine learning (ML) to facilitate differential diagnosis of cDI.

DESIGN

We analyzed data of 59 patients with cDI and 81 patients with PP from a prospective multicenter study evaluating the hypertonic saline test as new test approach to diagnose cDI. Our primary outcome was the diagnostic accuracy of the ML-based algorithm in differentiating cDI from PP patients.

METHODS

The data set used included 56 clinical, biochemical, and radiological covariates. We identified a set of five covariates which were crucial for differentiating cDI from PP patients utilizing standard ML methods. We developed ML-based algorithms on the data and validated them with an unseen test data set.

RESULTS

Urine osmolality, plasma sodium and glucose, known transsphenoidal surgery, or anterior pituitary deficiencies were selected as input parameters for the basic ML-based algorithm. Testing it on an unseen test data set resulted in a high area under the curve (AUC) score of 0.87. A further improvement of the ML-based algorithm was reached with the addition of MRI characteristics and the results of the hypertonic saline infusion test (AUC: 0.93 and 0.98, respectively).

CONCLUSION

The developed ML-based algorithm facilitated differentiation between cDI and PP patients with high accuracy even if only clinical information and laboratory data were available, thereby possibly avoiding cumbersome clinical tests in the future.

Diagnosis and treatment of brain injury complicated by hypernatremia

Hypernatremia is a common electrolyte disorder in patients with brain injury. The mortality of brain injury patients with severe hypernatremia may be as high as 86.8%. The efficacy of conventional treatment for hypernatremia is limited. Continuous renal replacement therapy (CRRT) can slowly, controllably, and continuously reduce the blood sodium concentration and gradually become an important treatment for severe hypernatremia patients. This review aims to provide important information for clinicians and clinical researchers by describing the etiology, diagnosis, hazards, conventional treatment, and CRRT treatment of hypernatremia in patients with traumatic brain injury.

Effects of Food and Multiple‐dose Administration on the Pharmacokinetic Properties of HR20033, a Sustained‐release Formulation of Henagliflozin and Metformin for the Treatment of Diabetes, in Healthy Chinese Volunteers

Henagliflozin proline and metformin hydrochloride sustained-release tablets (HR20033) are a fixed-dose combination of the novel, highly selective, and effective sodium-glucose cotransporter-2 inhibitor henagliflozin, with a metformin sustained-release layer for the treatment of type 2 diabetes mellitus in conjunction with dietary control and exercise. The aims of this study were to investigate the effect of a high-fat diet on the pharmacokinetics of henagliflozin and metformin after a single administration of HR20033 and the effect of repeated oral administration of HR20033 on their pharmacokinetics in healthy volunteers. The food-effect clinical study involved 18 healthy subjects randomized to receive either HR20033 in the fasted condition followed by HR20033 in the fed condition or the reverse schedule, with the two doses separated by a washout period of at least 7 days. The multiple-dose clinical study was conducted on 10 healthy subjects. In the food-effect study, compared with those in the fasted condition, the area under the blood concentration curve (AUC) and peak concentration (C_max ) of henagliflozin decreased by 12.64% and 40.89%, respectively, while the AUC of metformin increased by 31.13% and C_max decreased by 7.09% in the fed state. There was no significant accumulation of HR20033 in the body after multiple oral doses. No serious adverse event was observed in either of the two clinical studies. Food did not have a clinically meaningful effect on the absorption of HR20033.

Diabetes insipidus: A rare endocrine complication of immune check point inhibitors: A case report and literature review

Immune checkpoint inhibitors (ICIs), including anti-programmed cell death protein 1 (PD-1), anti-programmed cell death protein ligand 1 (PD-L1) and anti-cytotoxic T-lymphocyte antigen 4 (CTLA-4) monoclonal antibodies, are novel therapeutic agents widely used in numerous malignancies. They are known to cause multiple immune-related endocrine adverse events (irAEs); however, anterior pituitary hypophysitis with secondary hypopituitarism is the most frequently reported irAE, especially in patients receiving anti-CTLA-4 treatment. By contrast, posterior pituitary involvement, such as central diabetes insipidus (CDI), is relatively rare and only few case reports have been published. The present report describes the case of a 53-year-old woman with metastatic melanoma treated with nivolumab an anti-PD-L1 monoclonal antibody. At 6 months after the initiation of nivolumab treatment, the patient was diagnosed with deficiency of the corticotrope and thyreotrope axes and in the following 2 months the patient was diagnosed with progressive development of polyuria-polydipsia syndrome. The diagnosis of partial CDI was retained based on plasma and urinary osmolalities, the water deprivation test and baseline copeptin levels as well as on the absence of the bright spot in the posterior pituitary in magnetic resonance imaging. Systematic research of the literature revealed a total of 13 cases reports (including 14 patients) presenting with CDI treated with monotherapy with CTLA-4 (n=5) or PD-1/PD-L1 Abs (n=6) or combined treatments (n=3). The improved understanding of the mechanisms of ICI action along with their extensive use should contribute to the early recognition of irAE symptoms. We hypothesized that clinicians should be aware of this clinical entity and its symptoms and treat it appropriately.

Analysis of curative effect of insulin external application on burn wounds of diabetic patients with different depths

To explore the curative effect of insulin external application on burn wounds of diabetic patients with different depths. A retrospective analysis of 114 diabetic burn patients in the First Hospital of Hebei Medical University from June 2019 to June 2022. According to the different treatment methods, they were divided into study group (insulin therapy) and control group (conventional therapy) with 57 cases in each. The wound healing time, dressing changes, scar healing after wound healing and adverse events were compared between two groups. Pain level, serum inflammatory factors, vascular endothelial growth factor (VEGF) and oxidative stress factors before and after treatment were compared. The wound healing time (17.23 ± 2.18 vs 20.31 ± 2.09 days) and the number of dressing changes (7.01 ± 1.23 vs 8.93 ± 1.32 times) in study group were significantly lower than those in control group (P < 0.05). Before treatment, there was no difference in pain level, VEGF, interleukin-1 (IL-1), tumour necrosis factor-α (TNF-α), malondialdehyde (MDA) and superoxide dismutase (SOD) between two groups (P > 0.05). However, the pain level, scar healing, IL-1, TNF-a and MDA in study group were significantly lower than those in control group after treatment (P < 0.05). And the VEGF and SOD in study group was significantly higher than that in control group (P < 0.05). External application of insulin can shorten the wound healing time of diabetic patients with different depths, reduce the number of dressing changes, promote scar healing after wound healing, relieve pain and reduce the level of inflammatory factors, which is worthy of clinical promotion.

Self-Amplifying RNA Approach for Protein Replacement Therapy

Messenger RNA (mRNA) technology has already been successfully tested preclinically and there are ongoing clinical trials for protein replacement purposes; however, more effort has been put into the development of prevention strategies against infectious diseases. Apparently, mRNA vaccine approval against coronavirus disease 2019 (COVID-19) is a landmark for opening new opportunities for managing diverse health disorders based on this approach. Indeed, apart from infectious diseases, it has also been widely tested in numerous directions including cancer prevention and the treatment of inherited disorders. Interestingly, self-amplifying RNA (saRNA)-based technology is believed to display more developed RNA therapy compared with conventional mRNA technique in terms of its lower dosage requirements, relatively fewer side effects, and possessing long-lasting effects. Nevertheless, some challenges still exist that need to be overcome in order to achieve saRNA-based drug approval in clinics. Hence, the current review discusses the feasibility of saRNA utility for protein replacement therapy on various health disorders including rare hereditary diseases and also provides a detailed overview of saRNA advantages, its molecular structure, mechanism of action, and relevant delivery platforms.

Diagnosis and Management of Central Diabetes Insipidus in Adults

Central diabetes insipidus (CDI) is a clinical syndrome which results from loss or impaired function of vasopressinergic neurons in the hypothalamus/posterior pituitary, resulting in impaired synthesis and/or secretion of arginine vasopressin (AVP). AVP deficiency leads to the inability to concentrate urine and excessive renal water losses, resulting in a clinical syndrome of hypotonic polyuria with compensatory thirst. CDI is caused by diverse etiologies, although it typically develops due to neoplastic, traumatic, or autoimmune destruction of AVP-synthesizing/secreting neurons. This review focuses on the diagnosis and management of CDI, providing insights into the physiological disturbances underpinning the syndrome. Recent developments in diagnostic techniques, particularly the development of the copeptin assay, have improved accuracy and acceptability of the diagnostic approach to the hypotonic polyuria syndrome. We discuss the management of CDI with particular emphasis on management of fluid intake and pharmacological replacement of AVP. Specific clinical syndromes such as adipsic diabetes insipidus and diabetes insipidus in pregnancy as well as management of the perioperative patient with diabetes insipidus are also discussed.

Monitoring and Management of Bardet-Biedl Syndrome: What the Multi-Disciplinary Team Can Do

Bardet – Biedl syndrome is a rare autosomal recessive multisystem non-motile ciliopathy. It has heterogeneous clinical manifestations. It is caused by mutations in 26 genes encoding BBSome proteins, chaperonines, and IFT complex. The main clinical features are: retinal cone-rod dystrophy, central obesity, postaxial polydactyly, cognitive impairment, hypogonadism and genitourinary anomalies, and kidney disease. The onset of clinical manifestations is variable which makes the diagnosis difficult in some patients. Because of the multiple system involvement, a multidisciplinary approach is necessary. The purpose of this review is to provide monitoring and management directions for a better approach to these patients.

Dex modulates the balance of water-electrolyte metabolism by depressing the expression of AVP in PVN

Dexmedetomidine (Dex) is a highly selective α2 adrenergic agonist used in clinical anesthesia. Studies have shown that Dex can act on the collecting duct and reduce the body’s water reabsorption, thereby increasing water discharge. However, the specific mechanism of Dex on water homeostasis remains unclear. The hypothalamus is the regulatory center of water and salt balance and secretes related neurochemical hormones, such as arginine vasopressin (AVP), to regulate the discharge of water and salt. The paraventricular nucleus (PVN) and supraoptic nucleus (SON) in the hypothalamus are also considered to be the key targets of the thirst loop. They are responsible for the secretion of AVP. The suprachiasmatic nucleus (SCN) is also one of the brain regions where AVP neurons are densely distributed in the hypothalamus. This study used C57BL/6J mice for behavior, immunofluorescence, and blood analysis experiments. Our results showed that Dex could not only depress the expression of AVP in the PVN but also reduce serum AVP concentration. The animal water intake was decreased without impairing the difference in food consumption and the urine excretion was enhanced after the intraperitoneal injection of Dex, while AVP supplementation restored the water intake and inhibited the urine excretion of mice in the Dex group. In addition, the renin-angiotensin-aldosterone system is vital to maintaining serum sodium concentration and extracellular volume. We found that serum sodium, serum chloride, serum aldosterone (ALD) concentration, and plasma osmolality were decreased in the Dex group, which inhibited water reabsorption, and the plasma osmolarity of mice in the Dex group supplemented with AVP was significantly higher than that in Dex group. We also found that Dex significantly increased the concentration of blood urea nitrogen and decreased the concentration of creatinine within the normal range of clinical indicators, indicating that there was no substantive lesion in the renal parenchyma. These results showed that Dex could modulate the balance of water-electrolyte metabolism by depressing the expression of AVP in PVN without impairing renal function.

Research progress of placental vascular pathophysiological changes in pregnancy-induced hypertension and gestational diabetes mellitus

The placenta is a vital organ for fetal development, providing the fetus with nutrients, oxygen, and other important factors. Placenta is rich in blood vessels. Abnormal placental vascular function and blood circulation may lead to insufficient blood supply to the fetus in the uterus, leading to serious consequences such as pregnancy complications, fetal distress and even stillbirth. Pregnancy-induced hypertension (PIH) and gestational diabetes mellitus (GDM) are common complications of pregnancy. Recent studies report that pregnancy complications are often accompanied by changes in placental vascular structure and function. What are the physiological characteristics of human placental blood vessels? What are the pathological changes in the state of PIH and GDM? What are the relationships between these pathological changes and the occurrence of these pregnancy complications? Answers to these questions not only increase the understanding of placental vascular characteristics, but also provide important information for revealing the pathological mechanism of PIH and GDM. This article will summarize the research on the pathological changes of placental blood vessels in PIH and GDM, hoping to further unravel the physiological and pathological characteristics of placental blood vessels in the state of PIH and GDM, provide information for guiding clinical treatment for PIH and GDM.

A Diagnostic Enigma of Central Versus Nephrogenic Diabetes Insipidus: What Does the Value of Copeptin Signify?

Diabetes insipidus (DI) is a rare disease characterized by hypotonic urine output and polydipsia. We report the case of a 50-year-old male admitted for diabetic ketoacidosis (DKA) in an intensive care unit with sepsis and alcoholic pancreatitis who later developed DI. He had a high copeptin level of >21.4 pmol/L, suggesting DI of nephrogenic origin. At presentation, he had DKA-associated osmotic diuresis. His later finding of elevated copeptin suggesting partial nephrogenic DI created a diagnostic enigma.

Differential diagnosis of hyponatremia and hypernatremia

Dysnatremias are among the most common mineral imbalances encountered in clinical practice. Both hyponatremia and hypernatremia are associated with increased morbiditidy and mortality and represent negative prognostic factors regardless of their cause. Serum osmolality, extracellular fluid volume and sodium urine concentration are important parameters for evaluation the cause and differential diagnosis. The rate of onset of ionic disorder and severity of clinical symptoms are essential. While acute disorders with symptoms are treated immediately, in chronic disorders, thorough diagnostic evaluation and a careful approach to their correction are necessary. Especially with rapid substitution of chronic hyponatremia, there is a risk of osmotic demyelination syndrome. Therefore, a slow correction of the serum sodium level with frequent mineralogram checks is required.

Acute Sheehan’s syndrome manifesting initially with diabetes insipidus postpartum: a case report and systematic literature review

Purpose

Acute Sheehan’s syndrome is a rare, but potentially life-threatening, obstetric event that can be complicated by diabetes insipidus. Little information on the diagnosis and treatment of Sheehan’s syndrome with diabetes insipidus is available. We report on a 28-year-old patient who developed acute Sheehan’s syndrome with diabetes insipidus after giving birth, and on a systematic review of similar cases.

Methods

We performed a systematic review of the literature cataloged in PubMed and Google Scholar using the keywords “Sheehan syndrome” OR “Sheehan's syndrome” AND “diabetes insipidus” to identify relevant case reports published between 1990 and 2021. Eight Reports met the inclusion criteria (English-language abstracts available, onset in the puerperium, information about the day of the onset).

Results

In the present case, postpartum curettage was necessary to remove the residual placenta. The total amount of blood loss was severe (2500 ml). On the second day postpartal, the patient developed polyuria. Laboratory analysis revealed hypernatremia with increased serum osmolality and decreased urinary osmolality. Hormone analysis showed partial hypopituitarism involving the thyroid, corticotropic, and gonadotropic axes. The prolactin level was elevated. Brain magnetic resonance imaging showed pituitary gland infarction. Desmopressin therapy was initiated and resolved the polyuria. Hormone replacement therapy was administered. Four months later, the patient was well, with partial diabetes insipidus. The literature review indicated that this case was typical in terms of symptoms and disease onset. Most reported cases involve hypotension and peripartum hemorrhage, but some patients without hemorrhage also develop Sheehan’s syndrome. Elevated prolactin levels are uncommon and associated with poor prognosis in patients with Sheehan’s syndrome.

Conclusion

Acute Sheehan’s syndrome with diabetes insipidus involves nearly all pituitary hormone axes, indicating severe disease. Prolactin elevation could suggest that a case of Sheehan’s syndrome is severe.

[Perioperative management of the brain-dead organ donor : Anesthesia between ethics and evidence]

Hintergrund

Die Anzahl postmortal gespendeter Organe ist in Deutschland weit geringer als der Bedarf. Dies unterstreicht die Wichtigkeit einer optimalen Versorgung während des gesamten Prozesses der Organspende.

Fragestellung

Es existieren internationale Leitlinien und nationale Empfehlungen zu intensivmedizinischen organprotektiven Maßnahmen beim Organspender. Für das anästhesiologische Management fehlen evidenzbasierte Empfehlungen. Ziel dieser Übersichtsarbeit ist es, anhand der vorhandenen Evidenz die pathophysiologischen Veränderungen des irreversiblen Hirnfunktionsausfalls zu rekapitulieren und sich kritisch mit den empfohlenen Behandlungsstrategien und therapeutischen Zielgrößen auseinanderzusetzen. Auch auf ethische Aspekte der Betreuung des postmortalen Organspenders wird eingegangen.

Methode

Diese Übersichtsarbeit basiert auf einer selektiven Literaturrecherche in PubMed (Suchwörter: „brain dead donor“, „organ procurement“, „organ protective therapy“, „donor preconditioning“, „perioperative donor management“, „ethical considerations of brain dead donor“). Internationale Leitlinien und nationale Empfehlungen wurden besonders berücksichtigt.

Ergebnisse

Insgesamt ist die Evidenz für optimale intensivmedizinische und perioperative organprotektive Maßnahmen beim postmortalen Organspender sehr gering. Nationale und internationale Empfehlungen zu Zielwerten und medikamentösen Behandlungsstrategien unterscheiden sich teilweise erheblich: kontrollierte randomisierte Studien fehlen. Der Stellenwert einer Narkose zur Explantation bleibt sowohl unter pathophysiologischen Gesichtspunkten als auch aus ethischer Sicht ungeklärt.

Schlussfolgerungen

Die Kenntnisse über die pathophysiologischen Prozesse im Rahmen des irreversiblen Hirnfunktionsausfalls und die organprotektiven Maßnahmen sind ebenso Grundvoraussetzung wie die ethische Auseinandersetzung mit dem Thema postmortale Organspende. Nur dann kann das Behandlungsteam in dieser herausfordernden Situation sowohl dem Organempfänger als auch dem Organspender und seinen Angehörigen gerecht werden.

Transient Antidiuretic Hormone Insufficiency Caused by Severe Hyperosmolar Hyperglycemic Syndrome Based on Nephrogenic Diabetes Insipidus

BACKGROUND

The hyperosmolar hyperglycemic state (HHS), an acute complication of diabetes mellitus with plasma hyperosmolarity, promotes the secretion of anti-diuretic hormone (ADH) and reduces the storage of ADH. Magnetic resonance T1-weighted imaging reflects ADH storage in the posterior pituitary lobe, which disappears when the storage is depleted. Whether the HHS induces ADH depletion leading to clinical manifestations has been unclear.

CASE REPORT

A 55-year-old Japanese woman was admitted to our center because of mental disturbance and hypotension. She had received lithium carbonate for bipolar disorder and presented with polydipsia and polyuria from 15 years of age. On admission, she had mental disturbance (Glasgow Coma Scale, E4V1M1), hypotension (systolic blood pressure, 50 mmHg), and tachycardia (pulse rate, 123/min). Plasma glucose was 697 mg/dL osmolality was 476 mOsm/kg•H2O, and bicarbonate was 23.7 mmol/L. The diagnoses of HHS and hypovolemic shock were made. During treatment with fluid replacement and insulin therapy, the urine volume continued to be approximately 3 to 4 L/day, and an endocrine examination revealed ADH insufficiency and nephrogenic diabetes insipidus. Desmopressin 10 μg/day and trichlormethiazide 2 mg/day were necessary and administered, and the endogenous ADH secretion improved gradually. The signal intensity of the pituitary posterior lobe, initially decreased on magnetic resonance T1 images, was also improved.

CONCLUSION

This patient had ADH insufficiency associated with ADH depletion due to hyperosmolarity and nephrogenic diabetes insipidus. Clinicians should be aware of the risk of the development of critical HHS and relative ADH insufficiency in patients being treated with lithium carbonate.

Role of copeptin in the diagnosis of traumatic neuroendocrine dysfunction

Traumatic neuroendocrine dysfunction may present with diabetes insipidus (DI) or with the syndrome of inappropriate antidiuretic hormone secretion (SIADH). Both these pathologies involve a disturbance in the antidiuretic hormone (ADH) secretion, causing dysnatremias. Diagnosis of posttraumatic ADH dysfunction is hampered by technical difficulties in ADH assessment, and relies mostly on non-specific serum sodium, serum and urine osmolality and diuresis, often leading to misdiagnosis in the acute care setting. Research now focuses on the diagnostic role of copeptin, a peptide secreted together with ADH in an equimolar fashion, and which can be accurately evaluated. Recent studies identified cut-off values of 2.6 pmol/L for baseline copeptin and of 4.9 and 3.8 pmol/L for hypertonic saline infusion and arginine infusion stimulated copeptin, respectively, for the diagnosis of DI in patients with polyuria-polydipsia syndrome. Although SIADH is more difficult to be explored due to its heterogeneity, a ratio of copeptin to urinary sodium below 30 pmol/mmol identifies euvolemic hyponatremia. Exploring the role of copeptin assessment in patients with traumatic brain injury (TBI) in the acute phase may improve their diagnosis accuracy, management and outcome.

Clinical and Functional Characterization of a Novel Mutation in AVPR2 Causing Nephrogenic Diabetes Insipidus in a Four-Generation Chinese Family

Background: Congenital nephrogenic diabetes insipidus (CNDI) is a rare inherited disease that is caused by mutations in arginine vasopressin receptor 2 (AVPR2) or aquaporin 2 (AQP2). Functional analysis of the mutated receptor is necessary to verify the impact of the mutation on receptor function and suggest some possible therapeutic strategies for specific functional defects. Methods: Family history and clinical information were collected. Whole-exome sequencing and sanger sequencing were performed to determine the potential genetic cause of diabetes insipidus. The identified variant was classified according to the American College of Medical Genetics (ACMG) criteria. Bioinformatic analysis was performed to predict the function of the identified variation. Moreover, wild-type and mutated AVPR2 vectors were constructed and transfection to HEK-293T cells. Immunofluorescence experiments were performed to investigate the expression and localization of the mutated protein and cAMP parameter assays were used to measure its activity in response to AVP. Results: The heights of the adult members affected with polyuria and polydipsia were normal, but all affected children had growth retardation. Next-generation sequencing identified a novel mutation in AVPR2 gene (c.530T > A) in this family. Bioinformatic analysis indicated that the mutation in AVPR2 changed the hydropathic characteristic of the protein and was probably deleterious. Although immunofluorescence showed that the mutated AVPR2 was normally expressed in the cell surface, the intracellular cAMP concentration stimulated by AVP was significantly lower in cells transfected with mutated AVPR2 than cells transfected with wild-type AVPR2. Based on the ACMG criteria, the novel c.530T > A variant of the AVPR2 gene was likely pathogenic and the affected family members were diagnosed as CNDI. After the confirmation of the diagnosis, the proband was treated with compound amiloride hydrochloride and rhGH, the symptoms of polyuria, polydipsia and growth retardation were all improved. Conclusion: These findings suggested that the novel mutation in AVPR2 (c.530T > A) was a true disease-causing variant with mild effects, which could be classified as a type III mutant receptor. Moreover, investigations of the function of growth hormone axis could be important for the pediatric CNDI patients with extreme short stature, and rhGH treatment might improve the final adult heights in these patients.