Causes of reversible nephrogenic diabetes insipidus: A systematic review

Assessment of drug-induced electrolyte disorders in intensive care units: a multicenter observational study

Objective

Electrolyte disorder (ED) is frequently encountered critically ill patients during admission or admission to the intensive care unit (ICU). This study aimed to determine the frequency of ED encountered in ICU patients to evaluate the relationship of ED with drugs.

Methods

This prospective, multicenter study was conducted in the medical and anesthesiology ICUs of two training and research hospitals and included patients with at least one ED during admission or hospitalization in the ICUs. The relationship between ED and the drug was evaluated by calculating the logistic probabilistic method scale (LPMS) and the expert panel's evaluation. The correlation between EDs and LPMS was determined using Kendal tau. A binary logistic regression model was preferred in the analysis of factors related to ED. Statistical significance was set as p < 0.05.

Results

A total of 117 patients were included in the study. A total of 165 EDs were detected, including at least one in 88 (75.2%) patients. According to the expert panel, 61 (21.7%) of EDs were drug-related, whereas according to the LPMS, 111 (39.6%) (p < 0.001). Mortality (50% vs. 13.7%) and mechanical ventilation rates (52.2% vs. 17.2%) were significantly higher in patients with ED (p < 0.001). Patients with ED had 8.352 times higher odds of exhibiting mortality (OR: 8.352, %95 CI: 1.598-43.648, p: 0.012) and need mechanical ventilation with higher odds of 3.229 (OR: 3.229 95% CI: 0.815-12.787 p: 0.045). Patient who required enteral or parenteral feeding were associated with an increased likelihood of exhibiting ED (respectively OR: 30.057, %95 CI: 2.265-398.892, p: 0.01, OR: 5.537, %95 CI: 1.406-21.800, p: 0.014).

Conclusion

EDs are very common in the ICU. Dysnatremia was detected more commonly in other EDs. It has also been found that patients with ED are more often under mechanical ventilation, have more prolonged hospitalizations, and have higher mortality rates than patients without ED. The suitability of LPMS for assessing ED-drug relationships in the ICU context is questioned.

Lithium-induced Nephrogenic Diabetes Insipidus with Efficacy of Desmopressin in Combination with Thiazide Diuretics and Non-steroidal Anti-inflammatory Drugs: A Case Report with a Review of the Literature

Nephrogenic diabetes insipidus (NDI) is characterized by excessive urination and an inability to concentrate urine. Lithium is the most common cause of acquired NDI. Treatment typically involves thiazide diuretics and nonsteroidal anti-inflammatory drugs (NSAIDs). However, the efficacy of desmopressin in NDI remains unclear. We herein report a case of lithium-induced NDI in a 71-year-old woman with lithium-induced NDI. Thiazide diuretics and NSAIDs reduced the urine output by approximately 40% compared to pretreatment, while the addition of desmopressin reduced it by approximately 70%. This case suggests that desmopressin can be a viable treatment option for lithium-induced NDI.

New Advances in the Pharmacology and Toxicology of Lithium: A Neurobiologically Oriented Overview

Over the last six decades, lithium has been considered the gold standard treatment for the long-term management of bipolar disorder due to its efficacy in preventing both manic and depressive episodes as well as suicidal behaviors. Nevertheless, despite numerous observed effects on various cellular pathways and biologic systems, the precise mechanism through which lithium stabilizes mood remains elusive. Furthermore, there is recent support for the therapeutic potential of lithium in other brain diseases. This review offers a comprehensive examination of contemporary understanding and predominant theories concerning the diverse mechanisms underlying lithium's effects. These findings are based on investigations utilizing cellular and animal models of neurodegenerative and psychiatric disorders. Recent studies have provided additional support for the significance of glycogen synthase kinase-3 (GSK3) inhibition as a crucial mechanism. Furthermore, research has shed more light on the interconnections between GSK3-mediated neuroprotective, antioxidant, and neuroplasticity processes. Moreover, recent advancements in animal and human models have provided valuable insights into how lithium-induced modifications at the homeostatic synaptic plasticity level may play a pivotal role in its clinical effectiveness. We focused on findings from translational studies suggesting that lithium may interface with microRNA expression. Finally, we are exploring the repurposing potential of lithium beyond bipolar disorder. These recent findings on the therapeutic mechanisms of lithium have provided important clues toward developing predictive models of response to lithium treatment and identifying new biologic targets. SIGNIFICANCE STATEMENT: Lithium is the drug of choice for the treatment of bipolar disorder, but its mechanism of action in stabilizing mood remains elusive. This review presents the latest evidence on lithium's various mechanisms of action. Recent evidence has strengthened glycogen synthase kinase-3 (GSK3) inhibition, changes at the level of homeostatic synaptic plasticity, and regulation of microRNA expression as key mechanisms, providing an intriguing perspective that may help bridge the mechanistic gap between molecular functions and its clinical efficacy as a mood stabilizer.

Chapter 1: Evaluation of kidney function in patients undergoing anticancer drug therapy, from clinical practice guidelines for the management of kidney injury during anticancer drug therapy 2022

The prevalence of CKD may be higher in patients with cancer than in those without due to the addition of cancer-specific risk factors to those already present for CKD. In this review, we describe the evaluation of kidney function in patients undergoing anticancer drug therapy. When anticancer drug therapy is administered, kidney function is evaluated to (1) set the dose of renally excretable drugs, (2) detect kidney disease associated with the cancer and its treatment, and (3) obtain baseline values for long-term monitoring. Owing to some requirements for use in clinical practice, a GFR estimation method such as the Cockcroft-Gault, MDRD, CKD-EPI, and the Japanese Society of Nephrology's GFR estimation formula has been developed that is simple, inexpensive, and provides rapid results. However, an important clinical question is whether they can be used as a method of GFR evaluation in patients with cancer. When designing a drug dosing regimen in consideration of kidney function, it is important to make a comprehensive judgment, recognizing that there are limitations regardless of which estimation formula is used or if GFR is directly measured. Although CTCAEs are commonly used as criteria for evaluating kidney disease-related adverse events that occur during anticancer drug therapy, a specialized approach using KDIGO criteria or other criteria is required when nephrologists intervene in treatment. Each drug is associated with the different disorders related to the kidney. And various risk factors for kidney disease associated with each anticancer drug therapy.

A novel association of osmotic demyelination in Sjögren's syndrome prompts revisiting role of aquaporins in CNS demyelinating diseases: A literature review

BACKGROUND

Primary Sjögren's syndrome (SS) is a chronic systemic autoimmune disease with varied neurological manifestations. SS is associated with anti-aquaporin-4 antibody (AQP4-IgG)-positive neuromyelitis optica spectrum disorder (NMOSD), a demyelinating autoimmune disorder of the central nervous system (CNS). Intriguingly, there are reports of osmotic demyelinating syndrome (ODS), a supposedly non-inflammatory disorder, in the context of SS and renal tubular acidosis (RTA), both of which are not yet established risk factors for ODS.

METHODS

A literature search was undertaken to identify case reports of ODS in patients with SS. Details of the clinical and laboratory features of these patients were compiled. Additionally, we searched for NMOSD in patients with SS. We looked for co-existing RTA in patients with SS-ODS as well as SS-NMOSD. We also screened for reports of ODS in RTA without underlying SS.

RESULTS & DISCUSSION

We identified 15 patients (all women, median age 40 years) with ODS in SS, and all of these patients had comorbid RTA. There were only three reported cases of ODS in RTA without underlying SS. We identified a total of 67 patients with SS-NMOSD, of whom only 3 (4.5%) had RTA. Hence, unlike NMOSD, the development of ODS in SS requires a prolonged osmotic or electrolyte abnormality caused by the comorbid RTA. The 15 patients with ODS and SS -RTA, showed heterogeneous clinical manifestations and outcomes. The most common symptom was quadriparesis, seen in 14 of the 15 patients. Eleven of the 15 patients had one of the following features, either alone or in combination: worsening of the sensorium, extensor plantar response, dysphagia/dysarthria, and facial palsy. The latter four manifestations were present at the onset in 7 patients and later in the course of the illness in the remaining 4 patients. Ocular palsy was seen in only four of the 15 patients and was a late manifestation. One patient who had extensive long-segment myelitis and subsequent ODS died, but most patients recovered without significant sequelae. None had hyponatremia, while all patients had hypokalemia and/or hypernatremia. Hypokalemia causing nephrogenic diabetes insipidus (NDI) followed by rapid rise in sodium and the resultant osmotic stress could potentially explain the occurrence of ODS in SS-RTA. Aquaporin (AQP) in astrocytes is implicated in ODS, and renal AQP is downregulated in NDI. Antibodies against AQPs are present in some patients with SS. Defective AQP is therefore a common link underlying all the connected diseases, namely SS, NDI, and ODS, raising the possibility of immune-mediated AQP dysfunction in the pathogenesis.

CONCLUSION

The hitherto unreported association between SS-RTA and ODS may implicate SS and/or RTA in the development of ODS. In the setting of SS-RTA, ODS must be suspected when a patient with flaccid quadriparesis does not respond to the correction of potassium or develops additional neurological features along with a rise in sodium. Defective functions of AQPs may be a possible mechanism linking demyelinating CNS lesions, SS, and RTA. Studies evaluating AQP functions and serum antibodies against AQPs in these conditions are warranted.

Electrolytes disturbances in cancer patients

PURPOSE OF REVIEW

Hypernatremia, hyperphosphatemia, hypocalcaemia, hyperkalaemia and hypermagnesemia are electrolytes disturbances that can arise in cancer patients in relation to unique causes that are related to the cancer itself or its treatment and can lead to delay or interruption of cancer therapy. This article summarizes these main causes, the proposed pathophysiology and the recommended management for these disturbances.

RECENT FINDINGS

There have been many cancer drugs approved in the field of oncology over the past several years and a subset of these drugs have been associated with electrolytes disturbances. This includes, for example, immune checkpoint inhibitor related hyperkalemia, fibroblast growth factor 23 inhibitor associated hyperphosphatemia and epidermal growth factor receptor inhibitor associated hypomagnesemia and hypocalcaemia.

SUMMARY

This article provides an updated review of certain electrolytes disturbance in cancer patients and allows clinicians to have a greater awareness and knowledge of these electrolyte abnormalities in efforts to early recognition and timely management.

Effect of Admission Serum Calcium Levels and Length of Stay in Patients with Acute Pancreatitis: Data from the MIMIC-III Database

Objective. We retrospectively investigated the effect of admission serum calcium levels on length of stay (LOS) in patients hospitalized with acute pancreatitis (AP). Methods. Clinical data for 3156 patients diagnosed with AP were obtained from the Multiparametric Intelligent Monitoring in Intensive Care III (MIMIC-III) database. Restricted cubic spline curve (RCS) functions of dose-response analysis curves and logistic regression analysis were used to analyze the relationship between admission serum calcium levels and the LOS. Results. All patients were divided into 2 groups (<8.5 mg/dl group and ≥8.5 mg/dl group) based on RCS analysis. RCS showed a significant nonlinear negative correlation between blood calcium levels and the LOS ( $p<0.001$ ). In addition, compared with patients with blood calcium <8.5 mg/dl, multivariate logistic regression analysis showed that patients with blood calcium ≥8.5 mg/dl had a reduced risk of the LOS >2 days (aOR = 0.653; 95% CI 0.507–0.842; $p=0.001$ ), a reduced risk of the LOS >5 days (aOR = 0.589; 95% CI 0.503–0.689; $p<0.001$ ), and a reduced risk of the LOS >7 days (aOR = 0.515; 95% CI 0.437–0.609; $p<0.001$ ). And similar results were found in the subgroup analysis. Conclusion. Our findings suggest that low blood calcium increases the LOS in patients with AP. More attention is needed for patients with combined low blood calcium levels (<8.5 mg/dl) in hospitalized AP patients.

Diagnosis and management of hypernatraemia in children

Hypernatraemia is most commonly caused by excessive loss of solute-free water or decreased fluid intake; less often, the aetiology is salt intoxication. Especially infants, young children and individuals with a lack of access to water are at risk of developing hypernatraemia. Diagnosis is based on detailed history, physical examination and basic laboratory tests. Correction of hypernatraemia must be slow to prevent cerebral oedema and irreversible brain damage. This article reviews the aetiology, differential diagnosis and management of conditions associated with paediatric hypernatraemia. Distinguishing states with water deficiency from states with salt excess is important for proper management of hypernatraemic patients.

Chemotherapy Side-Effects: Not All DNA Damage Is Equal

Recent advances have increased survival rates of children and adults suffering from cancer thanks to effective anti-cancer therapy, such as chemotherapy. However, during treatment and later in life they are frequently confronted with the severe negative side-effects of their life-saving treatment. The occurrence of numerous features of accelerated aging, seriously affecting quality of life, has now become one of the most pressing problems associated with (pediatric) cancer treatment. Chemotherapies frequently target and damage the DNA, causing mutations or genome instability, a major hallmark of both cancer and aging. However, there are numerous types of chemotherapeutic drugs that are genotoxic and interfere with DNA metabolism in different ways, each with their own biodistribution, kinetics, and biological fate. Depending on the type of DNA lesion produced (e.g., interference with DNA replication or RNA transcription), the organ or cell type inflicted (e.g., cell cycle or differentiation status, metabolic state, activity of clearance and detoxification mechanisms, the cellular condition or micro-environment), and the degree of exposure, outcomes of cancer treatment can largely differ. These considerations provide a conceptual framework in which different classes of chemotherapeutics contribute to the development of toxicities and accelerated aging of different organ systems. Here, we summarize frequently observed side-effects in (pediatric) ex-cancer patients and discuss which types of DNA damage might be responsible.

The cascade to a serendipitous discovery of lithium-induced nephrogenic diabetes insipidus

Lithium therapy is a common treatment for affective disorders and is widely regarded as a lifesaving drug. However, because its elimination is almost wholly unchanged via the kidneys, both acute and long-term adverse effects relating to toxicity may occur, including declining renal function and nephrogenic diabetes insipidus (DI). DI may be difficult to detect and is frequently preceded by dehydration and which, in our patient, was discovered by chance. We describe a case of an elderly woman on chronic lithium therapy for bipolar affective disorder who initially presented with dehydration from vomiting but possibly developed extra-pontine myelinolysis (EPM) after over-zealous correction of hyponatraemia. Steroids administered appeared to have prevented further progression but a persisting hyperosmolar state then alerted us to the presence of nephrogenic DI. Although both conditions were later successfully reversed with no obvious chronic sequelae, the recovery of the patient was protracted. Clinicians should be vigilant for complications of managing dehydration states in people prescribed with lithium.

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

Diabetes insipidus is a disorder characterized by excretion of large amounts of hypotonic urine. Four entities have to be differentiated: central diabetes insipidus resulting from a deficiency of the hormone arginine vasopressin (AVP) in the pituitary gland or the hypothalamus, nephrogenic diabetes insipidus resulting from resistance to AVP in the kidneys, gestational diabetes insipidus resulting from an increase in placental vasopressinase and finally primary polydipsia, which involves excessive intake of large amounts of water despite normal AVP secretion and action. Distinguishing between the different types of diabetes insipidus can be challenging. A detailed medical history, physical examination and imaging studies are needed to detect the aetiology of diabetes insipidus. Differentiation between the various forms of hypotonic polyuria is then done by the classical water deprivation test or the more recently developed hypertonic saline or arginine stimulation together with copeptin (or AVP) measurement. In patients with idiopathic central DI, a close follow-up is needed since central DI can be the first sign of an underlying pathology. Treatment of diabetes insipidus or primary polydipsia depends on the underlying aetiology and differs in central diabetes insipidus, nephrogenic diabetes insipidus and primary polydipsia. This review will discuss issues and newest developments in diagnosis, differential diagnosis and treatment, with a focus on central diabetes insipidus.

Bendamustine-induced nephrogenic diabetes insipidus - A case report

INTRODUCTION

In patients with relapsed or refractory lymphoma, high-dose chemoimmunotherapy with subsequent autologous hematopoietic cell transplantation (HCT) is a standard of care. Bendamustine, an alkylating agent, is used in the BeEAM (bendamustine, etoposide, cytarabine, melphalan) protocol for conditioning therapy before autologous HCT in patients with relapsed or refractory lymphoma who are eligible for transplant. There is no consensus regarding an optimal salvage regimen and the approach varies according to toxicity.

CASE REPORT

We present a case of partial nephrogenic diabetes insipidus after receiving bendamustine, as part of the BeEAM protocol.Management and outcome: The patient was managed with parenteral fluid administration and intranasal desmopressin before the condition resolved on its own.

DISCUSSION

We summarize published reports of bendamustine-induced diabetes insipidus.

Anticancer Medications and Sodium Dysmetabolism

Therapeutic advances have revolutionised cancer treatment over the last two decades, but despite improved survival and outcomes, adverse effects to anticancer therapy such as dyselectrolytaemias do occur and need to be managed appropriately. This review explores essential aspects of sodium homeostasis in cancer with a focus on alterations arising from anticancer medications. Sodium and water balance are tightly regulated by close interplay of stimuli arising from hypothalamic osmoreceptors, arterial and atrial baroreceptors and the renal juxtaglomerular apparatus. This delicate balance can be disrupted by cancer itself, as well as the medications used to treat it. Some of the conventional chemotherapeutics, such as alkylating agents and platinum-based drugs, can cause hyponatraemia and, on rare occasions, hypernatraemia. Other conventional agents such as vinca alkaloids, as well as newer targeted cancer therapies including small molecule inhibitors and monoclonal antibodies, can cause hyponatraemia, usually as a result of inappropriate antidiuretic hormone secretion. Hyponatraemia can also sometimes occur secondarily to drug-induced hypocortisolism or salt-wasting syndromes. Another atypical but distinct mechanism for hyponatraemia is via pituitary dysfunction induced by immune checkpoint inhibitors. Hypernatraemia is uncommon and occasionally ensues as a result of drug-induced nephrogenic diabetes insipidus. Identification of the aetiology and appropriate management of these conditions, in addition to averting treatment-related problems, can be lifesaving in critical situations.

Diabetes Insipidus After Discontinuation of Vasopressin Infusion for Treatment of Shock

OBJECTIVES

Vasopressin has achieved common usage for the treatment of catecholamine-requiring and catecholamine-resistant shock. Diabetes insipidus is a syndrome characterized by excretion of abnormally large volumes of dilute urine. To date, very few reports of diabetes insipidus after discontinuation of vasopressin infusion have been published; the majority of previous reports describe neurosurgical patients. The purpose of the present study was to investigate the occurrence rate of diabetes insipidus after discontinuation of vasopressin infusion among patients treated with vasopressin infusion for shock.

DESIGN

Retrospective analysis of electronic health records of patients receiving continuous vasopressin infusion for the treatment of shock within a 5-year period (2012-2016).

SETTING

Medical, surgical, and cardiothoracic ICUs within one academic medical center.

PATIENTS

One-thousand eight-hundred ninety-six patients received vasopressin infusion for the treatment of shock.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The occurrence rate of diabetes insipidus after discontinuation of vasopressin infusion was 1.53% among all patients. Sixteen of 29 patients with diabetes insipidus after discontinuation of vasopressin infusion had undergone cardiothoracic intervention, such as coronary artery bypass graft and valve replacement surgery, extracorporeal membrane oxygenation, and placement of ventricular assist devices. No neurosurgical patients were identified in our cohort. In a control group of patients receiving norepinephrine but not vasopressin infusion for treatment of shock, criteria for diabetes insipidus were observed in two of 1,320 subjects (0.15%).

CONCLUSIONS

Despite a paucity of published reports, diabetes insipidus after discontinuation of vasopressin infusion appears not to be a rare phenomenon, and is likely to be encountered by intensivists who regularly employ vasopressin for the treatment of vasoplegic shock. Previous reports consisted predominantly of neurosurgical patients. Our findings demonstrate the occurrence of diabetes insipidus after discontinuation of vasopressin infusion among patients with septic shock as well as vasoplegic shock after cardiothoracic intervention. The mechanism of diabetes insipidus after discontinuation of vasopressin infusion remains to be elucidated but may involve transient downregulation of V2 receptors induced by exposure to supraphysiological doses of vasopressin.

Lithium Chloride and GSK3 Inhibition Reduce Aquaporin-2 Expression in Primary Cultured Inner Medullary Collecting Duct Cells Due to Independent Mechanisms

Lithium chloride (LiCl) is a widely used drug for the treatment of bipolar disorders, but as a side effect, 40% of the patients develop diabetes insipidus. LiCl affects the activity of the glycogen synthase kinase 3 (GSK3), and mice deficient for GSK3β showed a reduction in the urine concentration capability. The cellular and molecular mechanisms are not fully understood. We used primary cultured inner medullary collecting duct cells to analyze the underlying mechanisms. LiCl and the inhibitor of GSK3 (SB216763) induced a decrease in the aquaporin-2 (Aqp2) protein level. LiCl induced downregulation of Aqp2 mRNA expression while SB216763 had no effect and TWS119 led to increase in expression. The inhibition of the lysosomal activity with bafilomycin or chloroquine prevented both LiCl- and SB216763-mediated downregulation of Aqp2 protein expression. Bafilomycin and chloroquine induced the accumulation of Aqp2 in lysosomal structures, which was prevented in cells treated with dibutyryl cyclic adenosine monophosphate (dbcAMP), which led to phosphorylation and membrane localization of Aqp2. Downregulation of Aqp2 was also evident when LiCl was applied together with dbcAMP, and dbcAMP prevented the SB216763-induced downregulation. We showed that LiCl and SB216763 induce downregulation of Aqp2 via different mechanisms. While LiCl also affected the mRNA level, SB216763 induced lysosmal degradation. Specific GSK3β inhibition had an opposite effect, indicating a more complex regulatory mechanism.

Impact of Changes in Serum Calcium Levels on In-Hospital Mortality

Background and objectives: Calcium concentration is strictly regulated at both the cellular and systemic level, and changes in serum calcium levels can alter various physiological functions in various organs. This study aimed to assess the association between changes in calcium levels during hospitalization and mortality. Materials and Methods: We searched our patient database to identify all adult patients admitted to our hospital from January 1st, 2009 to December 31st, 2013. Patients with ≥2 serum calcium measurements during the hospitalization were included. The serum calcium changes during the hospitalization, defined as the absolute difference between the maximum and the minimum calcium levels, were categorized into five groups: 0–0.4, 0.5–0.9, 1.0–1.4, 1.5–1.9, and ≥2.0 mg/dL. Multivariable logistic regression was performed to assess the independent association between calcium changes and in-hospital mortality, using the change in calcium category of 0–0.4 mg/dL as the reference group. Results: Of 9868 patients included in analysis, 540 (5.4%) died during hospitalization. The in-hospital mortality progressively increased with higher calcium changes, from 3.4% in the group of 0–0.4 mg/dL to 14.5% in the group of ≥2.0 mg/dL (p < 0.001). When adjusted for age, sex, race, principal diagnosis, comorbidity, kidney function, acute kidney injury, number of measurements of serum calcium, and hospital length of stay, the serum calcium changes of 1.0–1.4, 1.5–1.9, and ≥2.0 mg/dL were significantly associated with increased in-hospital mortality with odds ratio (OR) of 1.55 (95% confidence interval (CI) 1.15–2.10), 1.90 (95% CI 1.32–2.74), and 3.23 (95% CI 2.39–4.38), respectively. The association remained statistically significant when further adjusted for either the lowest or highest serum calcium. Conclusion: Larger serum calcium changes in hospitalized patients were progressively associated with increased in-hospital mortality.

Systematic review and practical guideline for the prevention and management of the renal side effects of lithium therapy

Lithium is the first line therapy of bipolar mood disorder. Lithium-induced nephrogenic diabetes insipidus (Li-NDI) and lithium nephropathy (Li-NP, i.e., renal insufficiency) are prevalent side effects of lithium therapy, with significant morbidity. The objective of this systematic review is to provide an overview of preventive and management strategies for Li-NDI and Li-NP. For this, the PRISMA guideline for systematic reviews was used. Papers on the prevention and/or treatment of Li-NDI or Li-NP, and (influenceable) risk factors for development of Li-NDI or Li-NP were included. We found that the amount of evidence on prevention and treatment of Li-NDI and Li-NP is scarce. To prevent Li-NDI and Li-NP we advise to use a once-daily dosing schedule, target the lowest serum lithium level that is effective and prevent lithium intoxication. We emphasize the importance of monitoring for Li-NDI and Li-NP, as early diagnosis and treatment can prevent further progression and permanent damage. Collaboration between psychiatrist, nephrologist and patients themselves is essential. In patients with Li-NDI and/or Li-NP cessation of lithium therapy and/or switch to another mood stabilizer should be considered. In patients with Li-NDI, off label therapy with amiloride can be useful.

Nrf2 activation protects against lithium-induced nephrogenic diabetes insipidus

Lithium (Li) is the mainstay pharmacotherapeutic mood stabilizer in bipolar disorder. Its efficacious use is complicated by acute and chronic renal side effects, including nephrogenic diabetes insipidus (NDI) and progression to chronic kidney disease (CKD). The nuclear factor erythroid-derived 2-related factor 2 (Nrf2) pathway senses and coordinates cellular responses to oxidative and electrophilic stress. Here, we identify that graded genetic activation of Nrf2 protects against Li-induced NDI (Li-NDI) and volume wasting via an aquaporin 2-independent mechanism. Renal Nrf2 activity is differentially expressed on functional segments of the nephron, and its activation along the distal tubule and collecting duct directly modulates ion transporter expression, mimicking paradoxical effects of diuretics in mitigating Li-NDI. In addition, Nrf2 reduces cyclooxygenase expression and vasoactive prostaglandin biosynthesis. Pharmacologic activation of Nrf2 confers protective effects, confirming this pathway as a potentially novel druggable target for the prevention of acute and chronic renal sequelae of Li therapy.

Hypercalcemia Heralding Pneumocystis jirovecii Pneumonia in an HIV-Seronegative Patient with Diffuse Cutaneous Systemic Sclerosis

Pneumocystis pneumonia (PCP) is a life-threatening fungal infection occurring in immunocompromised patients such as HIV-positive patients with low CD4 cell count or patients under heavy immunosuppressive therapy. We report the case of a 59-year-old male with severe diffuse cutaneous systemic sclerosis presenting with asthenia, dry cough and worsening shortness of breath for the last 15 days. Biological studies were remarkable for PTH-independent severe hypercalcemia with low 25-hydroxyvitamin D and a paradoxically elevated 1,25-dihydroxyvitamin D. Early bronchoalveolar lavage allowed for PCP diagnosis and targeted treatment. We discuss the underlying physiopathology and difficulties regarding prophylaxis and treatment.

Partial nephrogenic diabetes insipidus associated with lithium therapy

A 40-year-old Caucasian man developed excessive thirst and polyuria particularly at night over the preceding 6 months. He had been taking lithium for 16 years for the treatment of bipolar affective disorder. Investigations revealed subnormal maximum urinary concentrating ability after 8 hours of water deprivation and only a borderline response of urine osmolality to exogenous desmopressin given by intramuscular injection. A plasma copeptin concentration was elevated at 23 pmol/L. These results were consistent with partial nephrogenic diabetes insipidus. He was encouraged to increase his water intake as dictated by his thirst. In addition, he received amiloride with some improvement in his symptoms. Clinicians should be aware of the risk of nephrogenic diabetes insipidus with long-term lithium use and seek confirmation by a supervised water deprivation test augmented with a baseline plasma copeptin. If increased water intake is insufficient to control symptoms, amiloride may be considered.

Diabetes insipidus

Diabetes insipidus (DI) is a disorder characterized by excretion of large amounts of hypotonic urine. Central DI results from a deficiency of the hormone arginine vasopressin (AVP) in the pituitary gland or the hypothalamus, whereas nephrogenic DI results from resistance to AVP in the kidneys. Central and nephrogenic DI are usually acquired, but genetic causes must be evaluated, especially if symptoms occur in early childhood. Central or nephrogenic DI must be differentiated from primary polydipsia, which involves excessive intake of large amounts of water despite normal AVP secretion and action. Primary polydipsia is most common in psychiatric patients and health enthusiasts but the polydipsia in a small subgroup of patients seems to be due to an abnormally low thirst threshold, a condition termed dipsogenic DI. Distinguishing between the different types of DI can be challenging and is done either by a water deprivation test or by hypertonic saline stimulation together with copeptin (or AVP) measurement. Furthermore, a detailed medical history, physical examination and imaging studies are needed to ensure an accurate DI diagnosis. Treatment of DI or primary polydipsia depends on the underlying aetiology and differs in central DI, nephrogenic DI and primary polydipsia.

Partial nephrogenic diabetes insipidus associated with Castleman's disease

Background

Nephrogenic diabetes insipidus (DI) secondary to a urinary tract obstruction is a rare condition. Herein, we report a case of partial nephrogenic DI due to obstructive uropathy in a patient with Castleman’s disease.

Case presentation

A 78-year-old man underwent computed tomography (CT) at his local hospital because of persistent edema of the leg and polyuria (both lasting approximately 2 months); retroperitoneal fibrosis was detected on the CT scan. An abdominal CT scan showed bilateral hydronephrosis, and a surgical biopsy of the para-aortic lymph node revealed Castleman’s disease. To resolve the hydronephrosis, a double J stent was inserted; however, his polyuria continued. As his serum osmolality (311 mOsm/kg) was greater than 300 mOsm/kg, and his serum sodium level was 149 mEq/L, a water deprivation test was not performed. On a vasopressin challenge test, his urine was not sufficiently concentrated to the expected range, indicating partial nephrogenic DI. He was treated with hydrochlorothiazide (25 mg/day), and his urine output gradually decreased to within the normal range. The patient recovered uneventfully and underwent treatment for Castleman’s disease.

Conclusion

To the best of our knowledge, this is the first case of partial nephrogenic DI due to obstructive uropathy associated with Castleman’s disease.

Electronic supplementary material

The online version of this article (10.1186/s12882-019-1343-9) contains supplementary material, which is available to authorized users.

Managing polyuria during lithium treatment: a preliminary prospective observational study

Objectives:

Lithium-treated patients with polyuria are at increased risk of lithium toxicity. We aimed to describe the clinical benefits and risks of different management strategies for polyuria in community lithium-treated patients.

Methods:

This is a naturalistic, observational, prospective 12-month cohort study of lithium-treated patients with polyuria attending a community mental health service in Dublin, Ireland. When polyuria was detected, management changed in one of four ways: (a) no pharmacological change; (b) lithium dose decrease; (c) lithium substitution; or (d) addition of amiloride.

Results:

Thirty-four participants were diagnosed with polyuria and completed prospective data over 12 months. Mean 24-hour urine volume decreased from 4852 to 4344 ml (p = 0.038). Mean early morning urine osmolality decreased from 343 to 338 mOsm/kg (p = 0.823). Mean 24-hour urine volume decreased with each type of intervention but did not attain statistical significance for any individual intervention group. Mean early morning urine osmolality decreased in participants with no pharmacological change and increased in participants who received a change in medication but these changes did not attain statistical significance. Only participants who discontinued lithium demonstrated potentially clinically significant changes in urine volume (mean decrease 747 ml in 24 hours) and early morning urine osmolality (mean increase 31 mOsm/kg) although this was not definitively proven, possibly owing to power issues.

Conclusions:

Managing polyuria by decreasing lithium dose does not appear to substantially improve objective measures of renal tubular dysfunction, whereas substituting lithium may do so. Studies with larger numbers and longer follow-up would clarify these relationships.

Elevated admission serum calcium phosphate product as an independent risk factor for acute kidney injury in hospitalized patients

BACKGROUND

Increased serum calcium-phosphate product (CaP) can result in acute kidney injury (AKI) due to tubular and interstitial calcium phosphate deposits. CaP of > 55 mg²/dL² is also associated with systemic calcification. However, the risk of AKI development among hospitalized patients with different admission calcium-phosphate product levels remains unclear.

METHODS

All adult hospitalized patients who had both admission serum calcium and phosphate levels available from 2009 through 2013 were enrolled. Admission CaP was categorized based on its distribution into six groups (<22, 22- < 27, 27- < 32, 32- < 37, 37- < 42 and ≥42 mg²/dL²). The odds ratio (OR) of in-hospital mortality by admission CaP, using the CaP category of < 22 mg²/dL² as the reference group, was obtained by logistic regression analysis.

RESULTS

After excluding patients with end-stage renal disease, without serum creatinine measurement, and those who presented with AKI at the time of admission, a total of 9,864 patients were studied. In-hospital AKI occurred in 1,478 patients (15.0%). The incidence of AKI among patients with admission CaP < 22, 22 to < 27, 27 to < 32, 32 to < 37, 37 to < 42, and ≥42 mg²/dL² was 11.1%, 12.4%, 14.9%, 15.2%, 17.5%, and 19.9%, respectively. After adjusting for potential confounders, a CaP ≥37 mg²/dL² was associated with an increased risk of developing AKI with OR of 1.53 (CI 1.19-1.96) and 1.63 (CI 1.25-2.14) in patients with admission CaP 37- < 42 and ≥42, respectively. Subgroup analysis based on eGFR consistently demonstrated that CaP ≥37 mg²/dL² was associated with an increased risk of developing AKI in both chronic kidney disease (CKD) and non-CKD patients.

CONCLUSION

Elevated admission CaP was independently associated with an increased risk for in-hospital AKI.

Lithium treatment, nephrogenic diabetes insipidus and the risk of hypernatraemia: a retrospective cohort study

BACKGROUND

Hypernatraemia is a serious condition that can potentially become life threatening. It is known that lithium is associated with polyuria and nephrogenic diabetes insipidus, risk factors for hypernatraemia. In this study, we tested the hypothesis that lithium treatment was a risk factor for hypernatraemia.

METHODS

We performed a retrospective cohort study in the Swedish region of Norrbotten into the effects and potential adverse effects of lithium treatment and other mood stabilizers (LiSIE). For this particular study, we included all patients who had experienced at least one episode with a sodium concentration ⩾150 mmol/L between 1997 and 2013. Medical records were reviewed regarding past or current lithium exposure, diabetes insipidus and other potential risk factors for hypernatraemia.

RESULTS

Of 2463 patients included, 185 (7.5%) had experienced 204 episodes of hypernatraemia within the 17-year review period. In patients 65 years or older, infections dominated as the cause with 51%. In patients younger than 65 years, intoxications, particularly with alcohol, dominated as the cause with 35%. In the whole sample, dehydration accounted for 12% of episodes, 25% of which in the context of suspected or confirmed nephrogenic diabetes insipidus. Of all episodes, 25% resulted in death, with infection being the most common cause of death in 62% of cases.

CONCLUSIONS

In our sample, infections and harmful use of substances including alcohol were the most common causes of hypernatraemia. Both current and past use of lithium also led to episodes of hypernatraemia, when associated with nephrogenic diabetes insipidus. Clinicians should remain vigilant, have a low threshold for checking sodium concentrations and consider even risk factors for hypernatraemia beyond lithium.

CONGENITAL NEPHROGENIC DIABETES INSIPIDUS IN A PRETERM INFANT: CASE PRESENTATION

Context

Diabetes insipidus (DI) is rare in the neonatal period but of great importance due to increased renal risk and mental retardation despite treatment.

Objective

This report describes the case of a patient with congenital nephrogenic diabetes insipidus (NDI). Detection of this pathology during the neonatal period, especially in premature newborns, is difficult because of the electrolyte variations that occur as a result of the immature kidney function.

Subjects and methods

The subject was a preterm infant with very low birth weight (VLBW) and persistent hypernatremic hyperosmolarity that developed polyuria and polydipsia in the first weeks of life.

Results

Taking into account blood and urine laboratory tests, vasopressin levels, as well as family history, the infant was diagnosed with congenital NDI. Early treatment allowed a good development, proving that the prevention of long-term complications is possible through multidisciplinary care and frequent monitoring. The particularity of this case was the presence of persistently elevated presepsin levels. This association prompted the investigation into underlying renal hypernatremia.

Conclusions

NDI is a rare condition and the onset in the neonatal period is a sign of severity and hereditary causality. Early diagnosis, symptomatic treatment and multidisciplinary monitoring may decrease the risk of long-term complications.

Admission calcium levels and risk of acute kidney injury in hospitalised patients

BACKGROUND

The risk of acute kidney injury (AKI) development among hospitalised patients with elevated calcium levels on admission remains unclear. The aim of this study was to assess the risk of AKI in hospitalised patients stratified by various admission serum calcium levels.

METHODS

This is a single-centre retrospective study conducted at a tertiary referral hospital. All hospitalised adult patients who had admission calcium levels available between 2009 and 2013 were enrolled. Admission calcium was categorised based on its distribution into six groups (≤7.9, 8.0-8.4, 8.5-8.9, 9.0-9.4, 9.5-9.9, and ≥10.0 mg/dL). The primary outcome was hospital-acquired AKI. Logistic regression analysis was performed to obtain the odds ratio of AKI for various admission calcium strata using calcium levels of 8.0-8.4 mg/dL (lowest incidence of AKI) as the reference group.

RESULTS

A total of 12 784 patients were studied. Hospital-acquired AKI occurred in 1779 (13.9%) patients. The incidence of AKI among patients with admission calcium ≤7.9, 8.0-8.4, 8.5-8.9, 9.0-9.4, 9.5-9.9 and ≥10 mg/dL was 14.7%, 11.7%, 11.8%, 14.6%, 15.8% and 17.3%, respectively. After adjusting for potential confounders, admission calcium levels ≤7.9, 9.0-9.4, 9.5-9.9 and ≥10 mg/dL were associated with increased risk of AKI with odds ratios of 1.36 (95%CI 1.08-1.72), 1.29 (95%CI 1.08-1.56), 1.38 (95%CI 1.14-1.68) and 1.51 (95%CI 1.19-1.91), respectively.

CONCLUSION

Admission hypocalcaemia and hypercalcaemia are associated with an increased risk for hospital acquired AKI. Patients with admission hypercalcaemia (≥10 mg/dL) carry a 1.51-fold risk for AKI development during hospitalisation.

Hereditary Nephrogenic Diabetes Insipidus: Pathophysiology and Possible Treatment. An Update

Under physiological conditions, excessive loss of water through the urine is prevented by the release of the antidiuretic hormone arginine-vasopressin (AVP) from the posterior pituitary. In the kidney, AVP elicits a number of cellular responses, which converge on increasing the osmotic reabsorption of water in the collecting duct. One of the key events triggered by the binding of AVP to its type-2 receptor (AVPR2) is the exocytosis of the water channel aquaporin 2 (AQP2) at the apical membrane the principal cells of the collecting duct. Mutations of either AVPR2 or AQP2 result in a genetic disease known as nephrogenic diabetes insipidus, which is characterized by the lack of responsiveness of the collecting duct to the antidiuretic action of AVP. The affected subject, being incapable of concentrating the urine, presents marked polyuria and compensatory polydipsia and is constantly at risk of severe dehydration. The molecular bases of the disease are fully uncovered, as well as the genetic or clinical tests for a prompt diagnosis of the disease in newborns. A real cure for nephrogenic diabetes insipidus (NDI) is still missing, and the main symptoms of the disease are handled with s continuous supply of water, a restrictive diet, and nonspecific drugs. Unfortunately, the current therapeutic options are limited and only partially beneficial. Further investigation in vitro or using the available animal models of the disease, combined with clinical trials, will eventually lead to the identification of one or more targeted strategies that will improve or replace the current conventional therapy and grant NDI patients a better quality of life. Here we provide an updated overview of the genetic defects causing NDI, the most recent strategies under investigation for rescuing the activity of mutated AVPR2 or AQP2, or for bypassing defective AVPR2 signaling and restoring AQP2 plasma membrane expression.

Medical Complications of Psychiatric Treatment: An Update

Psychiatric medications are used commonly in hospitalized patients and are particularly indicated in patients who are critically ill to manage many conditions. Due to their many indications in the intensive care unit (ICU), psychiatric medications should be closely monitored in these medically compromised patients for adverse reactions and medical complications because they may affect essentially all organ systems. These range from life-threatening reactions to other less significant effects, such as sedation, to other detrimental complications, such as pancreatitis. Knowledge of psychopharmacology as well as the diagnosis and treatment of these complications is imperative in treating patients in the ICU.

Arginine vasopressin (AVP): a review of its historical perspectives, current research and multifunctional role in the hypothalamo-hypophysial system

INTRODUCTION

This publication reviews the function of arginine vasopressin and focuses on the morphologic and functional correlation between the hormone and its effect on stress, the hypophysial-adrenocortical axis, neuroimmune responses, renal function and corticotroph pituitary tumors.

MATERIALS AND METHODS

A literature review was performed using various search engines for information regarding the morphology and the multifunctional role of arginine vasopressin.

RESULTS

Although a large number of studies were published discussing these interactions, there are several important areas that are still obscure.

CONCLUSION

The questions of how does arginine vasopressin affect the morphology and function of these various areas, and how does the secretion of ACTH and adrenocortical hormones influence the morphology of arginine vasopressin-producing cells and their hormone secretion requires further investigation.

Electrolyte disorders associated with the use of anticancer drugs

The use of anticancer drugs is beneficial for patients with malignancies but is frequently associated with the occurrence of electrolyte disorders, which can be hazardous and in many cases fatal. The review presents the electrolyte abnormalities that can occur with the use of anticancer drugs and provides the related mechanisms. Platinum-containing anticancer drugs induce hypomagnesemia, hypokalemia and hypocalcemia. Moreover, platinum-containing drugs are associated with hyponatremia, especially when combined with large volumes of hypotonic fluids aiming to prevent nephrotoxicity. Alkylating agents have been linked with the occurrence of hyponatremia [due to syndrome of inappropriate antidiuretic hormone secretion (SIADH)] and Fanconi's syndrome (hypophosphatemia, aminoaciduria, hypouricemia and/or glucosuria). Vinca alkaloids are associated with hyponatremia due to SIADH. Epidermal growth factor receptor monoclonal antibody inhibitors induce hypomagnesemia, hypokalemia and hypocalcemia. Other, monoclonal antibodies, such as cixutumumab, cause hyponatremia due to SIADH. Tyrosine kinase inhibitors are linked to hyponatremia and hypophosphatemia. Mammalian target of rapamycin inhibitors induce hyponatremia (due to aldosterone resistance), hypokalemia and hypophosphatemia. Other drugs such as immunomodulators or methotrexate have been also associated with hyponatremia. The administration of estrogens at high doses, streptozocin, azacitidine and suramin may induce hypophosphatemia. Finally, the drug-related tumor lysis syndrome is associated with hyperphosphatemia, hyperkalemia and hypocalcemia. The prevention of electrolyte derangements may lead to reduction of adverse events during the administration of anticancer drugs.

Diagnostic Accuracy of Tests for Polyuria in Lithium-Treated Patients

In lithium-treated patients, polyuria increases the risk of dehydration and lithium toxicity. If detected early, it is reversible. Despite its prevalence and associated morbidity in clinical practice, it remains underrecognized and therefore undertreated. The 24-hour urine collection is limited by its convenience and practicality. This study explores the diagnostic accuracy of alternative tests such as questionnaires on subjective polyuria, polydipsia, nocturia (dichotomous and ordinal responses), early morning urine sample osmolality (EMUO), and fluid intake record (FIR). This is a cross-sectional study of 179 lithium-treated patients attending a general adult and an old age psychiatry service. Participants completed the tests after completing an accurate 24-hour urine collection. The diagnostic accuracy of the individual tests was explored using the appropriate statistical techniques. Seventy-nine participants completed all of the tests. Polydipsia severity, EMUO, and FIR significantly differentiated the participants with polyuria (area under the receiver operating characteristic curve of 0.646, 0.760, and 0.846, respectively). Of the tests investigated, the FIR made the largest significant change in the probability that a patient experiences polyuria (<2000 mL/24 hours; interval likelihood ratio, 0.18 and >3500 mL/24 hours; interval likelihood ratio, 14). Symptomatic questioning, EMUO, and an FIR could be used in clinical practice to inform the prescriber of the probability that a lithium-treated patient is experiencing polyuria.

Determinants of hypercalcemia and hypercalciuria in immobilized trauma patients

Hypercalcemia and hypercalciuria secondary to immobilization can be occasionally severe, producing an array of symptoms. This study looked at possible determinants of hypercalcemia and hypercalciuria in immobilized trauma patients. This is a prospective observational study carried out over a period of 7 months. Fifty-five immobilized trauma patients were evaluated weekly for 4 weeks for symptoms of hypercalcemia, total serum calcium and 24-h urinary calcium. The number of limbs immobilized had a significant relationship with hypercalcemia at the end of week 1 (P<0.001) and week 4 (P=0.008) and with hypercalciuria at the end of week 1 only (P<0.001). The number of bones fractured also had a significant relationship with hypercalcemia at the end of week 1 (P=0.005) and week 4 (P=0.019), as well as with hypercalciuria at the end of week 1 (P<0.001) and week 2 (P=0.036). Weight loss was significantly associated with hypercalcemia at the end of week 4 (P=0.014) and with hypercalciuria at the end of week 3 (P<0.001) and week 4 (P<0.001), whereas polyuria and polydipsia had a significant association with hypercalciuria at the end of week 2 (P<0.001) and week 3 (P=0.030). The number of limbs immobilized and bones fractured showed an early significant relationship with the development of hypercalcemia and hypercalciuria. Weight loss showed late association with hypercalcemia and hypercalciuria, whereas polyuria and polydipsia showed early association with hypercalciuria.

Risk factors for polyuria in a cross-section of community psychiatric lithium-treated patients

OBJECTIVES

Polyuria increases the risk of dehydration and lithium toxicity in lithium-treated patients. Risk factors have been inconsistently described and the variance of this adverse effect remains poorly understood. This study aimed to establish independent risk factors for polyuria in a community, secondary-level lithium-treated sample of patients.

METHODS

This was a cross-sectional study of the lithium-treated patients attending a general adult and an old age psychiatry service. Participants completed a 24-hour urine collection. Urine volume and the presence of polyuria were the outcomes of interest. The relationship between outcome and the participant's demographic and clinical characteristics was explored with univariable and multivariable analysis.

RESULTS

A total of 122 participants were included in the analysis, with 38% being diagnosed with polyuria. Female gender and increased body weight independently predicted the presence of polyuria (standardized regression coefficient 1.01 and 0.94, respectively; p = 0.002 and p = 0.003, respectively). Female gender and increased body weight, lithium dose, and duration of lithium treatment independently predicted higher 24-hour urine volumes (standardized regression coefficients 0.693, p < 0.0005; 0.791, p < 0.0005; 0.276, p = 0.043; 0.181, p = 0.034, respectively). Of three different weight metrics, lean body weight was the most predictive.

CONCLUSIONS

Female gender and increased body weight explain part of the variance of this adverse effect. Both risk factors offer fresh insights into the pathophysiology of this potentially reversible and dangerous adverse effect of lithium treatment. Future research should focus on understanding the differences between the genders and between different body compositions in terms of lithium pharmacokinetics and pharmacodynamics.

A novel therapeutic effect of statins on nephrogenic diabetes insipidus

Statins competitively inhibit hepatic 3-hydroxy-3-methylglutaryl-coenzyme A reductase, resulting in reduced plasma total and low-density lipoprotein cholesterol levels. Recently, it has been shown that statins exert additional ‘pleiotropic’ effects by increasing expression levels of the membrane water channels aquaporin 2 (AQP2). AQP2 is localized mainly in the kidney and plays a critical role in determining cellular water content. This additional effect is independent of cholesterol homoeostasis, and depends on depletion of mevalonate-derived intermediates of sterol synthetic pathways, i.e. farnesylpyrophosphate and geranylgeranylpyrophosphate. By up-regulating the expression levels of AQP2, statins increase water reabsorption by the kidney, thus opening up a new avenue in treating patients with nephrogenic diabetes insipidus (NDI), a hereditary disease that yet lacks high-powered and limited side effects therapy. Aspects related to water balance determined by AQP2 in the kidney, as well as standard and novel therapeutic strategies of NDI are discussed.

Tubulointerstitial injury associated with chemotherapeutic agents

Chemotherapy holds tremendous potential in improving the survival of patients with cancer. However, the side effects of these drugs, including those that affect the kidney, can adversely affect patient outcomes. Prompt recognition of these adverse kidney effects allows early intervention that can minimize or prevent patient morbidity. In this review, we examine the nephrotoxic potential of chemotherapy drugs. In concentrating on tubulointerstitial injury, we will review common agents that result in acute kidney injury due to acute tubular necrosis, tubulopathies, crystal nephropathy, acute interstitial nephritis, and chronic interstitial nephritis, and we will present preventive and management strategies.

Do Antidepressants Lower the Prevalence of Lithium-associated Hypernatremia in the Elderly? A Retrospective Study

Background

Clinically important measures of lithium-induced nephrogenic diabetes insipidus (NDI) such as hypernatremia have not been well-studied. This is especially relevant for the elderly who, in comparison to younger adults, may become symptomatic and require hospitalization with relatively small elevations in sodium levels. We hypothesized that antidepressant use, which has been associated with the syndrome of inappropriate antidiuretic hormone secretion, has a protective effect against lithium-associated hypernatremia in the elderly.

Methods

Retrospective cohort study of 55 geriatric psychiatry outpatients followed at tertiary-care hospitals. Patients using lithium and antidepressants were compared with those using lithium alone for prevalence rates of hypernatremia during a 15-year observational period.

Results

The prevalence of hypernatremia was less in patients who had concurrent use of lithium and antidepressants, as compared to lithium alone 3/35 (8.6%) vs. 8/20 (40%), OR 0.14, p = .011.

Conclusions

Our results suggest that elderly lithium patients are less likely to develop hypernatremia if they are taking antidepressants concurrently. Whether antidepressants may be useful in the prevention of lithium-associated hypernatremia should be assessed in future prospective observational or treatment studies.

Nephrogenic diabetes insipidus: essential insights into the molecular background and potential therapies for treatment

The water channel aquaporin-2 (AQP2), expressed in the kidney collecting ducts, plays a pivotal role in maintaining body water balance. The channel is regulated by the peptide hormone arginine vasopressin (AVP), which exerts its effects through the type 2 vasopressin receptor (AVPR2). Disrupted function or regulation of AQP2 or the AVPR2 results in nephrogenic diabetes insipidus (NDI), a common clinical condition of renal origin characterized by polydipsia and polyuria. Over several years, major research efforts have advanced our understanding of NDI at the genetic, cellular, molecular, and biological levels. NDI is commonly characterized as hereditary (congenital) NDI, arising from genetic mutations in the AVPR2 or AQP2; or acquired NDI, due to for exmple medical treatment or electrolyte disturbances. In this article, we provide a comprehensive overview of the genetic, cell biological, and pathophysiological causes of NDI, with emphasis on the congenital forms and the acquired forms arising from lithium and other drug therapies, acute and chronic renal failure, and disturbed levels of calcium and potassium. Additionally, we provide an overview of the exciting new treatment strategies that have been recently proposed for alleviating the symptoms of some forms of the disease and for bypassing G protein-coupled receptor signaling.