Central diabetes insipidus in children: Diagnosis and management

Imaging in malignant germ cell tumors involving the hypothalamo-neurohypophyseal axis: the evaluation of the posterior pituitary bright spot is essential

PURPOSE

Malignant intracranial germ cell tumors (GCTs) are rare diseases in Western countries. They arise in midline structures and diagnosis is often delayed. We evaluated imaging characteristics and early tumor signs of suprasellar and bifocal GCT on MRI.

METHODS

Patients with the diagnosis of a germinoma or non-germinomatous GCT (NGGCT) who received non-contrast sagittal T1WI on MRI pre-therapy were included. Loss of the posterior pituitary bright spot (PPBS), the expansion and size of the tumor, and the expansion and infiltration of surrounding structures were evaluated. Group comparison for histologies and localizations was performed.

RESULTS

A total of 102 GCT patients (median age at diagnosis 12.3 years, range 4.4-33.8; 57 males; 67 in suprasellar localization) were enrolled in the study. In the suprasellar cohort, NGGCTs (n = 20) were noticeably larger than germinomas (n = 47; p < .001). Each tumor showed involvement of the posterior lobe or pituitary stalk. A PPBS loss (total n = 98) was observed for each localization and entity in more than 90% and was related to diabetes insipidus. Osseous infiltration was observed exclusively in suprasellar GCT (significantly more frequent in NGGCT; p = .004). Time between the first MRI and therapy start was significantly longer in the suprasellar cohort (p = .005), with an even greater delay in germinoma compared to NGGCT (p = .002). The longest interval to treatment had circumscribed suprasellar germinomas (median 312 days).

CONCLUSION

A loss of the PPBS is a hint of tumor origin revealing small tumors in the neurohypophysis. Using this sign in children with diabetes insipidus avoids a delay in diagnosis.

Desmopressin Dose Requirements in Adults with Congenital and Acquired Central Diabetes Insipidus

Central diabetes insipidus is a rare disorder characterized by a deficiency of vasopressin. The first line drug to treat this disorder is a synthetic analogue of vasopressin, desmopressin.The primary aim of this retrospective register study was to compare desmopressin dose requirements in patients with acquired and congenital DI, and secondly to assess the influence of BMI on dose requirement and risk of hyponatremia with different drug administrations. We included all patients with suspected DI attending the endocrine department at Rigshospitalet, Copenhagen, Denmark in 2022. We identified 222 patients who were included whereof 130/222 (58.6%) were females and median age was 53 years (IQR 35 to 63). The etiology included 7/222 (3.2%) congenital and 215/222 (96.8%) acquired. After converting nasal and sublingual doses to equivalent oral doses, the median daily dose requirement was 600 μg in patients with congenital etiology compared to 200 μg in patients with acquired etiology (p=0.005). We found no association between BMI and desmopressin dose requirements (p=0.6). During the past 12 months, 66/215 (30.7%) had sodium levels<136 mmol/l including 20/215 (9.3%) with sodium levels<131 mmol/l. No increased risk of hyponatremia was found, when nasal and oral were compared (p=0.9). Daily desmopressin dose requirements were higher in patients with congenital DI compared to patients with acquired DI. However, this result was associated with uncertainty due to the small congenital group. BMI did not influence daily dose requirements and nor did type of administration influence the risk of hyponatremia.

Persistent hypernatremia secondary to adipsic central diabetes insipidus in a patient with herpes-induced meningoencephalitis and COVID-19 infection: a case report

Central diabetes insipidus (CDI) typically manifests as a polyuria-polydipsia syndrome, in which normonatremia is generally maintained through the polydipsia. A 53-year-old woman presented with diabetic ketosis and hyperosmolar hyperglycemic syndrome. Her medical history included herpes meningoencephalitis, which was associated with confusion and amnesia. On physical examination, she was apyretic, confused, and had signs of extracellular dehydration. Her capillary glucose concentration was high and her urine was positive for ketones. Laboratory investigations revealed severe hyperglycemia, hypernatremia (plasma hyperosmolarity of 393.6 mOsm/L), and mild acute renal failure. In addition, she had a paucisymptomatic COVID-19 infection. Intravenous rehydration with isotonic saline solution and insulin therapy were effective at controlling the ketosis and ameliorating the hyperglycemia, but failed to normalize the hypernatremia and hyperosmolarity. She was not thirsty and had a urine output of 1 L/day, with urinary hypotonicity. Desmopressin administration reduced the hypernatremia and hyperosmolarity to within their normal ranges, and the patient's urinary osmolarity increased to 743 mOsm/L. Therefore, adipsic CDI was diagnosed. Endocrine investigations revealed isolated central hypothyroidism. The results of pituitary magnetic resonance imaging were normal. Thus, patients with impaired thirst may have an atypical presentation of CDI. In addition, the diagnosis of adipsic CDI is particularly challenging.

Cell-penetrating peptides for transmucosal delivery of proteins

Enabling non-invasive delivery of proteins across the mucosal barriers promises improved patient compliance and therapeutic efficacies. Cell-penetrating peptides (CPPs) are emerging as a promising and versatile tool to enhance protein and peptide permeation across various mucosal barriers. This review examines the structural and physicochemical attributes of the nasal, buccal, sublingual, and oral mucosa that hamper macromolecular delivery. Recent development of CPPs for overcoming those mucosal barriers for protein delivery is summarized and analyzed. Perspectives regarding current challenges and future research directions towards improving non-invasive transmucosal delivery of macromolecules for ultimate clinical translation are discussed.

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.

The therapeutic effect of oral desmopressin lyophilisate formulation in children with central diabetes insipidus

OBJECTIVES

We aimed to assess the efficacy of oral use of oral desamino-D-arginine-8-vasopressin lyophilisate (OLD) in children with central diabetes insipidus (CDI).

METHODS

Clinical, laboratory, and imaging characteristics of twenty-five children with CDI treated with OLD were evaluated.

RESULTS

Fourteen boys and eleven girls with a mean age of 52.37 months were evaluated. These children (mean weight and height at admission, 26.81 ± 14.8 kg vs. 92.52 ± 30 cm) presented with failure to thrive, irritability, prolonged fever, polyuria and hypernatremia (mean sodium level, 143.12 ± 8.6 mEq/L). At the time of hypernatremia, mean serum and urine osmolality were 298.2 ± 18 mOsm/kg and 160.20 ± 8.7 mOsm/kg, respectively. ADH levels were undetectable (<0.5 pmol/L) at admission in all cases. Oral administration of desmopressin lyophilisate (120 µg/tablet) was initiated at a dose of 5 μg/kg/day in two divided doses together with controlled water intake to avoid hyponatremia. Serum sodium levels normalised in a mean duration of 15.2 ± 16.4 h with a mean decline rate of 0.12 ± 0.04 mEq/L/h. Nine children needed rehospitalization because of hypernatremia due to non-compliance. Four episode of hyponatremia was observed. Weight gain and growth were normal during the mean follow-up duration of 37.79 ± 48.2 months.

CONCLUSIONS

Administration of OLD was practical and safe in the treatment of CDI in children with CNS malformations in this small retrospective series.

Clinical and pathophysiological aspects of impaired water and sodium metabolism in newborns and neurological complication

This literature review covers the pathophysiological features of water and sodium exchange in newborns. The main mechanisms regulating fluid and electrolyte balance in newborns are poorly studied. The volume and composition of the extracellular fluid are provided by the functional activity of the kidneys under the control of the neuroendocrine system. The antidiuretic hormone plays the main role in the regulation of water excretion by the kidneys. The volume of intracellular fluid depends on the passive water transport with the participation of aquaporins. Lability of water and electrolyte metabolism in newborns may be accompanied by hyponatremia. For various pathological conditions in the neonatal period, certain types of hyponatremias are characteristic. Correction of hyponatremia should be carried out taking into account its pathophysiological type. Hyponatremia is a common complication associated with severe neonatal brain damage. Hyponatremia contributes to brain damage as an independent factor. The study of indicators of water and electrolyte balance in the neonatal period has an important prognostic value for early detection of damage to the central nervous system.

Genetic basis of nephrogenic diabetes insipidus

Nephrogenic diabetes insipidus is defined as an inability to concentrate urine due to a complete or partial alteration of the renal tubular response to arginine vasopressin hormone, resulting in excessive diluted urine excretion. Hereditary forms are caused by molecular defects in the genes encoding either of the two main renal effectors of the arginine vasopressin pathway: the AVPR2 gene, which encodes for the type 2 vasopressin receptor, or the AQP2 gene, which encodes for the water channel aquaporin-2. About 90% of cases of nephrogenic diabetes insipidus result from loss-of-function variants in the AVPR2 gene, which are inherited in a X-linked recessive manner. The remaining 10% of cases result from loss-of-function variants in the AQP2 gene, which can be inherited in either a recessive or a dominant manner. The main symptoms of the disease are polyuria, chronic dehydration and hypernatremia. These symptoms usually occur in the first year of life, although some patients present later. Diagnosis is based on abnormal response in urinary osmolality after water restriction and/or administration of exogenous vasopressin. Treatment involves ensuring adequate water intake on demand, possibly combined with thiazide diuretics, non-steroidal anti-inflammatory drugs, and a low-salt and protein diet. In this review, we provide an update on current understanding of the molecular basis of inherited nephrogenic insipidus diabetes.

Diagnostic value of magnetic resonance imaging ectopic posterior pituitary hyperintense signal in pituitary macroadenoma

Objective

When the lesions in the sellar region are large, they can involve both the inside and outside the sella, which brings challenges to the differential diagnosis of pituitary macroadenoma and lesions other than macroadenoma. Therefore, this study explored the diagnostic value of an ectopic posterior pituitary hyperintense signal (EPPHS) in pituitary macroadenoma and its possible causes.

Methods

The clinical and imaging data of 131 patients with sellar tumors or tumor-like lesions involving both intrasellar and extrasellar regions in the Affiliated Hospital of Guizhou Medical University from February 2011 to December 2021 were analyzed retrospectively. The diagnostic value of EPPHS in pituitary macroadenoma was analyzed. The differences in clinical and imaging indexes between the EPPHS-positive group and the EPPHS-negative group were compared.

Results

These 131 cases of sellar tumors or tumor-like lesions involving both intrasellar and extrasellar regions included 91 cases of pituitary macroadenoma and 40 cases of lesions other than macroadenoma. The receiver operator characteristic (ROC) curve analysis suggested that EPPHS had a diagnostic value in diagnosing pituitary macroadenoma [area under the curve (AUC) = 0.857, P = 0.0001]. Compared with the EPPHS negative group, the median prolactin level in the EPPHS positive group was significantly higher (P &lt; 0.05). Through ROC curve analysis, prolactin value was found to be of diagnostic value for EPPHS (AUC = 0.612, P = 0.0312).

Conclusion

In sellar tumors or tumor-like lesions involving both intrasellar and extrasellar regions, the appearance of EPPHS is helpful in the diagnosis of pituitary macroadenoma. The formation of EPPHS may be related to injuries to the pituitary stalk.

The Percutaneous Endoscopic Lumbar Debridement and Irrigation Drainage Technique for the First-Stage Treatment of Spontaneous Lumbar Spondylodiscitis: A Clinical Retrospective Study

Background

Minimally invasive or open surgery is contentious in the treatment of spondylodiscitis, therefore finding a balance between the two is urgently needed. In this study, we propose a new treatment paradigm for treating spontaneous lumbar spondylodiscitis by percutaneous endoscopic lumbar debridement and irrigation drainage (PELDID). Then, the Pola classification was used to guide subsequent treatment.

Methods

From November 2017 to April 2019, this study collected data on 16 patients with lumbar spondylodiscitis who were surgically treated utilizing this treatment paradigm in our department. Clinical effectiveness was determined using the visual analogue scale (VAS), the Oswestry Disability Index (ODI), the MOS 36-item short-form health survey (SF-36), and Kirkaldy-Willis criteria.

Results

All 16 patients completed the treatment using the above paradigm and were followed up for 28.13 ± 10.15 months. The preoperative Pola classification is as follows: 7 cases of type A, 3 cases of type B, and 6 cases of type C. After the first-stage surgery, the evaluation results of Pola classification were as follows: 8 cases of type A, 8 cases of type B, and 0 cases of type C. Four patients received second-stage surgery with internal fixation through the paravertebral multifidus space approach and intervertebral bone graft fusion through the transforaminal approach, and the reoperation rate was 25% (4/16 cases). The Visual analogue scale (VAS), Oswestry Disability Index (ODI), and SF-36 score all improved significantly from 2.43 ± 0.89 to 0.18 ± 0.40, from 77.31% ± 11.15%to 16.93% ± 5.45%, and from 18.34 ± 7.47 to 80.3 ± 15.36. The CRP and ESR decreased dramatically from 49.61 ± 48.84 to12.50 ± 12.18 and from 65.56 ± 26.89 to 29.68 ± 20.68. There were no recurrences of infection in our study.

Conclusions

The paradigm of the first-stage PELDID technique combined with the Pola classification system to guide the second-stage treatment for spontaneous spondylodiscitis is a novel and effective strategy for treating spontaneous spondylodiscitis.

Analysis on Value of Continuous Nursing Based on WeChat in Improving Healthy Quality of Life and Self-Management Behavior of Patients with Diabetic Nephropathy

Objective

To explore the value of continuous nursing (CN) based on WeChat in improving healthy quality of life and self-management behavior of patients with diabetic nephropathy (DN).

Methods

A total of 100 patients with DN who were treated in our hospital from November 2019 to January 2020 were selected. Thereinto, 54 patients who received CN based on WeChat were considered as the research group, and 46 patients who received the routine nursing intervention were considered as the control group. Peripheral blood samples were collected before nursing intervention (T0), 1 month after intervention (T1), and 2 months after intervention (T2) to test blood glucose, blood lipid, and renal function. Exercise of self-care agency (ESCA) scale and general self-efficacy scale (GSES) was conducted to evaluate patients' self-management ability, and a short-form 36-item health survey (SF-36) was conducted to evaluate their quality of life. Finally, the treatment compliance and satisfaction of patients were investigated.

Results

There was no marked difference in blood glucose, blood lipid, and renal function between groups at T0 (P > 0.05), but the research group was better than the control group at T1 and T2 (P < 0.05). After the nursing intervention, the scores of ESCA, GSES, and SF-36 in the research group were higher (P < 0.05). In addition, the treatment compliance rate and satisfaction of the research group were also higher.

Conclusion

CN based on WeChat can effectively improve the self-management behavior and quality of life of DN patients, which is extremely suitable for such chronic diseases with extremely long treatment cycles and can provide a more effective guarantee for their recovery.

Diagnosis and Management of New-Onset Central Diabetes Insipidus in Critically Ill Children Varies between Pediatric Critical Care Medicine and Pediatric Endocrinology Clinicians

The diagnosis and management of central diabetes insipidus in critically ill children is not standardized. Our objective was to characterize differences between Pediatric Critical Care Medicine (PCCM) and Pediatric Endocrinology (PE) clinicians in the diagnosis and management of new-onset CDI in the pediatric intensive care unit. We also sought to characterize knowledge gaps among general pediatrics (GP) residents. This is a scenario-based survey to assess patterns of diagnosis and management of new-onset CDI that was distributed to PCCM, PE, and GP clinicians who work in a quaternary care urban children's hospital. Of 275 PCCM, PE, and GP clinicians surveyed, 158 (57%) responded. More PCCM than PE clinicians relied on serum sodium levels (96 vs. 75%, p <0.01) and more PE than PCCM clinicians relied on serum osmolality (91 vs. 40%, p < .001) for diagnosis. Fewer PCCM than PE clinicians favored restricting IV fluids to two-thirds maintenance rate (4 vs. 37%, p <0.001). More PCCM than PE clinicians favored a starting dose of 0.5 milli-units/kg/h for IV vasopressin infusion (76 vs. 53%, p = 0.048). More PCCM clinicians than PE clinicians favored titrating the IV vasopressin infusion every 20 minutes (24 vs. 2%, p = 0.02), whereas more PE clinicians than PCCM clinicians favored titration every 60 minutes (38 vs. 14%, p = 0.03). GP residents earlier in training had greater self-reported gaps in knowledge. We observed substantial variability in the diagnosis and management of new-onset CDI in critically ill children among PCCM, PE, and GP clinicians. There is a need for greater standardization in care of these patients.

Evaluation of the etiological and clinical characteristics of pediatric central diabetes insipidus

OBJECTIVES

Central diabetes insipidus (CDI) is a rare but important disease of varying etiology that poses challenges in diagnosis and follow-up. Identifying diagnostic difficulties in patients with CDI will help ensure an optimal approach to their management and follow-up. This study aimed to characterize the clinical and etiological characteristics of CDI in pediatric patients.

METHODS

We analyzed the admission and follow-up data of CDI patients aged 0-18 years who were followed in our center between 2010 and 2019.

RESULTS

The study included 56 patients with a mean age at diagnosis of 7.92 ± 5.11 years and symptom duration of 8.65 ± 21.3 months. The patients were grouped by etiology into those with organic causes, such as structural anomalies, tumors, and trauma (group 1, n=41) and other causes (group 2, n=15). The prevalence of idiopathic CDI was 16%. At least one pituitary hormone deficiency was detected in 60.7%, the most common being thyroid stimulating hormone deficiency. Patients in group 1 had a higher mean age at diagnosis, shorter symptom duration, and higher frequency of other pituitary hormone deficiencies compared to group 2. Additionally, germinoma was detected 1 year subsequent to normal MRI findings at diagnosis and another patient was diagnosed with Langerhans cell histiocytosis (LCH) 5 years after diagnosis. All patients responded well to replacement therapies, but two patients with germinoma died during follow-up.

CONCLUSIONS

In the pediatric age group, intracranial organic pathologies are an important etiology of CDI, and despite a short symptomatic period, determining the cause may be challenging and prolonged. Patients presenting at a young age with a long history of symptoms and no other pituitary hormone deficiency are unlikely to have organic CDI. However, organic causes such as LCH should be evaluated at all ages. Patients with idiopathic disease are candidates for further etiological studies, and repeated cranial imaging is important during follow-up.

High-Resolution Computer Tomography Image Features of Lungs for Patients with Type 2 Diabetes under the Faster-Region Recurrent Convolutional Neural Network Algorithm

The objective of this study was to adopt the high-resolution computed tomography (HRCT) technology based on the faster-region recurrent convolutional neural network (Faster-RCNN) algorithm to evaluate the lung infection in patients with type 2 diabetes, so as to analyze the application value of imaging features in the assessment of pulmonary disease in type 2 diabetes. In this study, 176 patients with type 2 diabetes were selected as the research objects, and they were divided into different groups based on gender, course of disease, age, glycosylated hemoglobin level (HbA1c), 2 h C peptide (2 h C-P) after meal, fasting C peptide (FC-P), and complications. The research objects were performed with HRCT scan, and the Faster-RCNN algorithm model was built to obtain the imaging features. The relationships between HRCT imaging features and 2 h C-P, FC-P, HbA1c, gender, course of disease, age, and complications were analyzed comprehensively. The results showed that there were no significant differences in HRCT scores between male and female patients, patients of various ages, and patients with different HbA1c contents (P > 0.05). As the course of disease and complications increased, HRCT scores of patients increased obviously (P < 0.05). The HRCT score decreased dramatically with the increase in the contents of 2 h C-P and FC-P after the meal (P < 0.05). In addition, the results of the Spearman rank correlation analysis showed that the course of disease and complications were positively correlated with the HRCT scores, while the 2 h C-P and FC-P levels after meal were negatively correlated with the HRCT scores. The receiver operating curve (ROC) showed that the accuracy, specificity, and sensitivity of HRCT imaging based on Faster-RCNN algorithm were 90.12%, 90.43%, and 83.64%, respectively, in diagnosing lung infection of patients with type 2 diabetes. In summary, the HRCT imaging features based on the Faster-RCNN algorithm can provide effective reference information for the diagnosis and condition assessment of lung infection in patients with type 2 diabetes.

Approach to the Pediatric Patient: Central Diabetes Insipidus

Central diabetes insipidus (CDI) is a complex disorder in which large volumes of dilute urine are excreted due to arginine-vasopressin deficiency, and it is caused by a variety of disorders affecting the hypothalamic-posterior pituitary network. The differential diagnosis is challenging and requires a detailed medical history, physical examination, biochemical approach, imaging studies, and, in some cases, histological confirmation. Magnetic resonance imaging is the gold standard method for evaluating congenital or acquired cerebral and pituitary stalk lesions. Pituitary stalk size at presentation could be normal, but it may change over time, depending on the underlying condition, while other brain areas or organs may become involved during follow-up. Early diagnosis and treatment are crucial to avoid central nervous system damage and germ cell tumor dissemination and to minimize complications of multiple pituitary hormone defects. We provide a practical update on the diagnosis and management of patients with CDI and highlight several pitfalls that may complicate the differential diagnosis of conditions presenting with polyuria and polydipsia. The need for a careful and close follow-up of patients with apparently idiopathic CDI is particularly emphasized because the underlying condition may be recognized over time. The clinical scenario that we outline at the beginning of this article represents the basis for the discussion about how the etiological diagnosis of CDI can be overlooked and demonstrates how a water intake and urine output improvement can be a sign of progressive damage of both hypothalamus and anterior pituitary gland with associated pituitary hormonal deficiencies.

Studies on anti-rabphilin-3A antibodies in 15 consecutive patients presenting with central diabetes insipidus at a single referral center

Central diabetes insipidus (CDI) is a rare condition caused by various underlying diseases including inflammatory and autoimmune diseases, and neoplasms. Obtaining an accurate definitive diagnosis of the underlying cause of CDI is difficult. Recently, anti-rabphilin-3A antibodies were demonstrated to be a highly sensitive and specific marker of lymphocytic infundibuloneurohypophysitis (LINH). Here, we report a detailed case series, and evaluated the significance of anti-rabphilin-3A antibodies in differentiating the etiologies of CDI. A prospective analysis was conducted in 15 consecutive patients with CDI from 2013 to 2020 at a single referral center. Anti-rabphilin-3A antibodies were measured and the relationship between antibody positivity and the clinical/histopathological diagnoses was evaluated. Among 15 CDI patients, the positive anti-rabphilin-3A antibodies were found in 4 of 5 LINH cases, 3 of 4 lymphocytic panhypophysitis (LPH) cases, one of 2 sarcoidosis cases, and one intracranial germinoma case, respectively. Two Rathke cleft cyst cases and one craniopharyngioma case were negative. This is the first report of anti-rabphilin-3A antibodies positivity in CDI patients with biopsy-proven LPH. Measurement of anti-rabphilin-3A antibodies may be valuable for differentiating CDI etiologies.

Challenges and improvement needs in the care of patients with central diabetes insipidus

Central diabetes insipidus (CDI) is a rare condition, with significant impact on patient health and well-being. It is a chronic condition which usually requires meticulous long-term care. It can affect both children and adults. There is limited literature considering the needs and challenges inherent in providing high quality care to patients with CDI, across the care pathway. This paper seeks to address this gap by providing a unique and well-rounded understanding of clinical and healthcare systems-related challenges. It draws on insights from the literature, from direct clinical experience contributed by five clinicians as co-authors (providing insights from France, Ireland, Italy, Spain and the United Kingdom), and from patient perspectives provided through interviews with patient representatives from three patient organisations. We identify clinical challenges related to the diagnosis of CDI, including differentiating between other similar conditions and determining the underlying aetiology. Treatment is challenging, given the need to tailor medication to each patient’s needs and ongoing management is required to ensure that patients continue to respond adequately to treatment. Ongoing support is required when patients switch between formulations. We also identify healthcare systems challenges related to limited awareness of CDI amongst primary care physicians and general paediatricians, and the need for highly skilled specialist care and appropriate workforce capacity. There is also a significant need for raising awareness and for the education of both healthcare professionals and patients about different aspects of CDI, with the aim of supporting improved care and effective patient engagement with healthcare professionals. We reflect on this information and highlight improvement opportunities. These relate to developing guidance to support patients, carers, primary care physicians and general paediatricians to identify clinical features earlier, and to consider CDI as a possible diagnosis when a patient presents with suggestive symptoms.

Cardiac and respiratory arrest in a 12-year-old girl with acute permethrin oral toxicity: A case report

Permethrin (PER) is widely employed as the most frequently used type I synthetic pyrethroid insecticide. Despite its worldwide application, reports of pediatric toxicity following permethrin administration are scarce. The present report describes the case of a 12-year-old girl with cardiac and respiratory arrest resulting from self-induced oral toxicity by permethrin.

Diabetes insipidus

Diabetes insipidus (DI) is a disorder characterized by a high hypotonic urinary output of more than 50ml per kg body weight per 24 hours, with associated polydipsia of more than 3 liters a day [1,2]. Central DI results from inadequate secretion and usually deficient synthesis of Arginine vasopressin (AVP) in the hypothalamus or pituitary gland. Besides central DI further underlying etiologies of DI can be due to other primary forms (renal origin) or secondary forms of polyuria (resulting from primary polydipsia). All these forms belong to the Polyuria Polydipsia Syndrom (PPS). In most cases central and nephrogenic DI are acquired, but there are also congenital forms caused by genetic mutations of the AVP gene (central DI) [3] or by mutations in the gene for the AVP V2R or the AQP2 water channel (nephrogenic DI) [4]. Primary polydipsia (PP) as secondary form of polyuria includes an excessive intake of large amounts of fluid leading to polyuria in the presence of intact AVP secretion and appropriate antidiuretic renal response. Differentiation between the three mentioned entities is difficult [5], especially in patients with Primary polydipsia or partial, mild forms of DI [1,6], but different tests for differential diagnosis, most recently based on measurement of copeptin, and a thorough medical history mostly lead to the correct diagnosis. This is important since treatment strategies vary and application of the wrong treatment can be dangerous [7]. Treatment of central DI consists of fluid management and drug therapy with the synthetic AVP analogue Desmopressin (DDAVP), that is used as nasal or oral preparation in most cases. Main side effect can be dilutional hyponatremia [8]. In this review we will focus on central diabetes insipidus and describe the prevalence, the clinical manifestations, the etiology as well as the differential diagnosis and management of central diabetes insipidus in the out- and inpatient setting.

Familial neurohypophyseal diabetes insipidus: clinical, genetic and functional studies of novel mutations in the arginine vasopressin gene

PURPOSE

Familial neurohypophyseal diabetes insipidus (FNDI) is a rare disorder characterized by childhood-onset progressive polyuria and polydipsia due to mutations in the arginine vasopressin (AVP) gene. The aim of the study was to describe the clinical and molecular characteristics of families with neurohypophyseal diabetes insipidus.

METHODS

Five Portuguese families with autosomal dominant FNDI underwent sequencing of the AVP gene and the identified mutations were functionally characterized by in vitro studies.

RESULTS

Three novel and two recurrent heterozygous mutations were identified in the AVP gene. These consisted of one initiation codon mutation in the signal peptide coding region (c.2T > C, p.Met1?), three missense mutations in the neurophysin II (NPII) coding region (c.154T > C, p.Cys52Arg; c.289C > G, p.Arg97Gly; and c.293G > C, p.Cys98Ser), and one nonsense mutation in the NPII coding region (c.343G > T, p.Glu115Ter). In vitro transfection of neuronal cells with expression vectors containing each mutation showed that the mutations resulted in intracellular retention of the vasopressin prohormone. Patients showed progressive symptoms of polyuria and polydipsia, but with wide variability in severity and age at onset. No clear genotype-phenotype correlation was observed.

CONCLUSION

The intracellular accumulation of mutant vasopressin precursors supports the role of cellular toxicity of the mutant proteins in the etiology of the disorder and explains the progressive onset of the disorder. These findings further expand the AVP mutational spectrum in FNDI and contribute to the understanding of the molecular pathogenic mechanisms involved in FNDI.

Asymptomatic obstructive hydronephrosis associated with diabetes insipidus: a case report and review

The treatment of asymptomatic hydronephrosis due to ureteropelvic junction obstruction (UPJO), as well as the timing and indications for surgical intervention, remain controversial. Diabetes insipidus (DI) is a rare disease in infants that is known to cause non-obstructive hydronephrosis, while its association with obstructive hydronephrosis has not been reported. Some studies have found that increased water intake is a predisposing risk factor of developing hydronephrosis. However, there are no studies or guidelines that indicate the specific follow-up intervals and surgical indications for mild hydronephrosis if predisposing risk factors persist. A 46-month-old boy was admitted to our Urology Department with a history of Society of Fetal Urology (SFU) Grade 2 prenatal left hydronephrosis, which was stable at SFU Grade 1-2 at regular postnatal follow-ups. The patient developed polydipsia and polyuria three months prior to admission, then he was considered as primary polydipsia by endocrinology and was treated with fluid restriction while the examination was negative. Renal ultrasound at follow-up demonstrated severe left hydronephrosis with an anterior-posterior diameter (APD) of 6.25 cm three months after symptom onset. Diuretic renography (DR) revealed a renal function of 13.7% with a glomerular filtration rate (GFR) of 11.25 mL/min. The patient was otherwise asymptomatic without any abdominal pain or vomiting. He underwent left pyelostomy immediately as well as laparoscopic left dismembered ureteropelvioplasty after three months, and a diagnosis of UPJO was confirmed. The patient had an uncomplicated postoperative recovery and the result of follow-up renal ultrasound was stable. However, the symptoms of polydipsia and polyuria did not improve significantly. He underwent pituitary magnetic resonance imaging (MRI) and pathological examination, the results of which were consistent with central DI caused by Langerhans cell hyperplasia four months postoperatively. This case indicates the need to pay attention to children with mild hydronephrosis undergoing regular observation and conservative treatment, as a sudden aggravation of the hydronephrosis and a rapid decline of renal function may occur if DI persists.

Postoperative diabetes insipidus: how to define and grade this complication?

PURPOSE

Although transient diabetes insipidus (DI) is the most common complication of pituitary surgery, there is no consensus on its definition. Polyuria is the most overt symptoms of DI, but can also reflect several physiological adaptive mechanisms in the postoperative phase. These may be difficult to distinguish from and might coincide with DI. The difficulty to distinguish DI from other causes of postoperative polyuria might explain the high variation in incidence rates. This limits interpretation of outcomes, in particular complication rates between centers, and may lead to unnecessary treatment. Aim of this review is to determine a pathophysiologically sound and practical definition of DI for uniform outcome evaluations and treatment recommendations.

METHODS

This study incorporates actual data and the experience of our center and combines this with a review of literature on pathophysiological mechanisms and definitions used in clinical studies reporting of postoperative DI.

RESULTS

The occurrence of excessive thirst and/or hyperosmolality or hypernatremia are the best indicators to discriminate between pathophysiological symptoms and signs of DI and other causes. Urine osmolality distinguishes DI from osmotic diuresis.

CONCLUSIONS

To improve reliability and comparability we propose the following definition for postoperative DI: polyuria (urine production > 300 ml/hour for 3 h) accompanied by a urine specific gravity (USG) < 1.005, and at least one of the following symptoms: excessive thirst, serum osmolality > 300 mosmol/kg, or serum sodium > 145 mmol/L. To prevent unnecessary treatment with desmopressin, we present an algorithm for the diagnosis and treatment of postoperative DI.

Distribution of plasma copeptin levels and influence of obesity in children and adolescents

In recent years, a more stable AVP surrogate, called copeptin, has been used as an adjuvant diagnostic tool for dysnatremia in adults and appears to be promising even in the pediatric age. The aim of this study is to present the distribution of plasma copeptin in a large pediatric cohort and to observe the influence of fluid consumption and obesity on its values. A cohort of 128 children and adolescents was divided into two groups on the basis of nocturnal deprivation (group A) or free access to oral fluids in the 6-8 h before blood collection (group B). At all distribution percentiles, copeptin levels were higher (p < 0.0001) in group A, as were plasma sodium levels and osmolality (p = 0.02 and p = 0.008, respectively). The influence of BMI on copeptin levels was investigated by dividing the cohort into nonobese (group C) and obese children and adolescents (group D). Copeptin levels were higher in group D (p = 0.04).Conclusion: The measurement of copeptin could represent a useful tool for the diagnostic pathway of dysnatremic conditions, but its interpretation should take into consideration the state of hydration. Furthermore, it could also be a promising marker for obesity and metabolic syndrome, although this hypothesis needs further studies to be confirmed. What is Known: • Copeptin use as a diagnostic tool in AVP-related disorders, such as diabetes insipidus or syndrome of inappropriate secretion of antidiuretic hormone, is well established in adults • In pediatric age, few studies are available, but the preliminary data, including our previous study, seems to be promising. What is New: • In this study, we represent the distribution of copeptin levels in a pediatric cohort and show the significant influence of fluid ingestion on its plasma levels. • Also BMI seems to be a significant variable on copeptin levels and may be used as an obesity marker in pediatric age.