Cerebral salt wasting syndrome: review

Cerebral Salt Wasting Syndrome in the Setting of Hypovolemic Isotonic Hyponatremia: A Case Report

Cerebral salt wasting syndrome (CSWS) is a condition characterized as the loss of sodium secondarily due to an intracranial process, commonly following the neurosurgical resection of mass lesions. This condition leads to a hypovolemic hypotonic hyponatremia. The identification of this syndrome is often mistaken for syndrome of inappropriate anti-diuretic hormone (SIADH). The treatment for both conditions is vastly different. Given the risk of mortality when balancing sensitivities in hyponatremia and its commonality in clinical scenarios, a distinction is crucial. In this case report, we discuss a patient who presented with CSWS following the surgical resection of a pituitary adenoma. She subsequently developed hypernatremia, treated with DDAVP for the suspicion of diabetes insipidus. Once this was discontinued, she further presented with worsening hyponatremia. This hyponatremia persisted even after the discontinuation of DDAVP, with no significant intervention leading to hypovolemic isotonic hyponatremia, supporting a diagnosis of CSWS. Our findings stress the importance of the proper identification of hyponatremia with guided treatment following neurosurgical intervention and give physicians an insight into the anomalies of hyponatremia that should be further discussed.

Phenotypic Heterogeneity in Patients with Mutations in the Mitochondrial Complex I Assembly Gene NDUFAF5

BACKGROUND

Rare mutations in NADH:ubiquinone oxidoreductase complex assembly factor 5 (NDUFAF5) are linked to Leigh syndrome.

OBJECTIVE

We aimed to describe clinical characteristics and functional findings in a patient cohort with NDUFAF5 mutations.

METHODS

Patients with biallelic NDUFAF5 mutations were recruited from multi-centers in Taiwan. Clinical, laboratory, radiological, and follow-up features were recorded and mitochondrial assays were performed in patients' skin fibroblasts.

RESULTS

Nine patients from seven unrelated pedigrees were enrolled, eight homozygous for c.836 T > G (p.Met279Arg) in NDUFAF5 and one compound heterozygous for p.Met279Arg. Onset age had a bimodal distribution. The early-onset group (age <3 years) presented with psychomotor delay, seizure, respiratory failure, and hyponatremia. The late-onset group (age ≥5 years) presented with normal development, but slowly progressive dystonia. Combing 25 previously described patients, the p.Met279Arg variant was exclusively identified in Chinese ancestry. Compared with other groups, patients with late-onset homozygous p.Met279Arg were older at onset (P = 0.008), had less developmental delay (P = 0.01), less hyponatremia (P = 0.01), and better prognosis with preserved ambulatory function into early adulthood (P = 0.01). Bilateral basal ganglia necrosis was a common radiological feature, but brainstem and spinal cord involvement was more common with early-onset patients (P = 0.02). A modifier gene analysis showed higher concomitant mutation burden in early-versus late-onset p.Met279Arg homozygous cases (P = 0.04), consistent with more impaired mitochondrial function in fibroblasts from an early-onset case than a late-onset patient.

CONCLUSIONS

The p.Met279Arg variant is a common mutation in our population with phenotypic heterogeneity and divergent prognosis based on age at onset. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Suspected medullary washout leading to severe polyuria following delayed cerebral ischemia: a case report

BACKGROUND

Delayed cerebral ischemia is a clinical entity commonly encountered in patients presenting with acute neurological injury and is often complicated by dysnatremias, such as the cerebral salt wasting syndrome. In this case report, we described an exceptional case of polyuria attributed to an initial cerebral salt wasting phenomenon and iatrogenic-induced medullary washout.

CASE PRESENTATION

A 53-year-old woman was admitted to our hospital for the management of a Modified Fisher scale grade 4 subarachnoid hemorrhage due to a ruptured posterior communicating aneurysm. She was initially managed with coil embolization and external ventricular drain due to secondary hydrocephalus. Throughout the course of her hospitalization, she developed severe polyuria reaching up to 40L per day. To keep up with the excessive urinary losses and maintain appropriate cerebral perfusion, fluid replacement therapy was adjusted every hour, reaching up to 1.3 L of crystalloid per hour in addition to aminergic support. An initial diagnosis of partial diabetes insipidus, followed by a cerebral salt wasting syndrome was suspected. While the urine output continued to increase, her serum urea concentration progressively decreased to a point of almost being undetectable on day 9. At that time, the presence of an interstitial medulla washout was hypothesized. Various pharmacological and non-pharmacological interventions were progressively introduced to regain normal renal homeostasis, including non-steroidal anti-inflammatory drugs, fludrocortisone, oral urea and high-protein intake. Medications were progressively weaned, and the patient was successfully discharged from the ICU.

CONCLUSIONS

Cerebral salt wasting should be considered in the initial differential diagnosis of a patient presenting with polyuria in the context of acute neurological injury. Early recognition of this entity is critical to quickly implement proper management. However, as shown in this case report, the concomitance of delayed cerebral ischemia may complexify that management.

Cerebral Salt Wasting Syndrome Following Right Occipital Craniotomy in a Patient With Metastatic Lung Adenocarcinoma

Cerebral salt wasting syndrome (CSW) is characterized by excessive natriuresis leading to hyponatremia and hypovolemia. It is commonly encountered among patients who have undergone brain trauma or subarachnoid hemorrhage. The occurrence of CSW after neurosurgical procedures has been frequently reported in the pediatric age group; however, it is a rare phenomenon in adults. We describe the case of a 59-year-old female who developed symptoms of polyuria and polydipsia after a right occipital craniotomy.

Sodium Homeostasis, a Balance Necessary for Life

Body sodium (Na) levels must be maintained within a narrow range for the correct functioning of the organism (Na homeostasis). Na disorders include not only elevated levels of this solute (hypernatremia), as in diabetes insipidus, but also reduced levels (hyponatremia), as in cerebral salt wasting syndrome. The balance in body Na levels therefore requires a delicate equilibrium to be maintained between the ingestion and excretion of Na. Salt (NaCl) intake is processed by receptors in the tongue and digestive system, which transmit the information to the nucleus of the solitary tract via a neural pathway (chorda tympani/vagus nerves) and to circumventricular organs, including the subfornical organ and area postrema, via a humoral pathway (blood/cerebrospinal fluid). Circuits are formed that stimulate or inhibit homeostatic Na intake involving participation of the parabrachial nucleus, pre-locus coeruleus, medial tuberomammillary nuclei, median eminence, paraventricular and supraoptic nuclei, and other structures with reward properties such as the bed nucleus of the stria terminalis, central amygdala, and ventral tegmental area. Finally, the kidney uses neural signals (e.g., renal sympathetic nerves) and vascular (e.g., renal perfusion pressure) and humoral (e.g., renin-angiotensin-aldosterone system, cardiac natriuretic peptides, antidiuretic hormone, and oxytocin) factors to promote Na excretion or retention and thereby maintain extracellular fluid volume. All these intake and excretion processes are modulated by chemical messengers, many of which (e.g., aldosterone, angiotensin II, and oxytocin) have effects that are coordinated at peripheral and central level to ensure Na homeostasis.

Cerebral Salt Wasting Syndrome Associated with Status Epilepticus

Cerebral salt wasting syndrome (CSWS) is defined as a renal loss of sodium in cerebral disorders causing hyponatremia and loss of extracellular fluid volume. Similar laboratory findings may be seen in other conditions such as syndrome of inappropriate antidiuretic hormone secretion (SIADH). A 58-year-old male visited our emergency department because of the sudden development of seizures during sleep. Magnetic resonance imaging revealed subtle high signal intensity in the right hippocampus on diffusion-weighted imaging. Ictal rhythmic discharges were observed in the concordant area. Altered metal status, polyuria and laboratory test findings including hyponatremia were compatible with CSWS. After hydration and salt replacement, his mental state and hyponatremia gradually recovered. For diagnosing CSWS, meticulous physical examinations including analysis of fluid balance are essential. CSWS should be considered in patients with hyponatremia and polyuria. Accurate diagnosis of CSWS and SIADH is crucial as the treatment plans for these two conditions are completely different.

Disorders of Salt and Water Balance After Pituitary Surgery

Transsphenoidal surgery is the first-line treatment for many clinically significant pituitary tumors and sellar lesions. Although complication rates are low when performed at high-volume centers, disorders of salt and water balance are relatively common postoperatively. Both, or either, central diabetes insipidus (recently renamed arginine vasopressin deficiency - AVP-D), caused by a deficiency in production and/or secretion of arginine vasopressin, and hyponatremia, most commonly secondary to the syndrome of inappropriate antidiuresis, may occur. These conditions can extend hospital stay and increase the risk of readmission. This article discusses common presentations of salt and water balance disorders following pituitary surgery, the pathophysiology of these conditions, and their diagnosis and management.

Differential diagnosis between syndrome of inappropriate antidiuretic hormone secretion and cerebral/renal salt wasting syndrome in children over 1 year: proposal for a simple algorithm

Hyponatremia, especially if acute and severe, can be a life-threatening condition. Several conditions can trigger hyponatremia. In this review, we will discuss two conditions that can determine euvolemic hyponatremia: the cerebral/renal salt wasting (CRSW) syndrome and the syndrome of inappropriate secretion of antidiuretic hormone (SIADH), including the two subtypes: reset osmostat (RO) and nephrogenic syndrome of inappropriate antidiuresis (NSIAD) and their differential diagnoses. Despite the passage of over 70 years since its first description, to date, the true etiopathogenesis of CRSW syndrome, a rare cause of hypovolemic/euvolemic hyponatremia, is almost unknown. SIADH, including RO and NSIAD, is sometimes difficult to differentiate from CRSW syndrome; in its differential diagnosis, the clinical approach based on the evaluation of the extracellular volume (ECV) was proven insufficient. We therefore suggest a simple diagnostic algorithm based on the assessment of the degree of hyponatremia, urinary osmolality, and the assessment of the fraction of urate excretion (FEUa) in conditions of hyponatremia and after serum sodium correction, to be applied in children over 1 year of life.

Cerebral Salt Wasting Syndrome (CSW): An unusual cause of hypovolemia after spontaneous cerebral hemorrhage successfully treated with fludrocortisone

Our objective is to demonstrate the interest of thinking about Cerebral salt wasting syndrome (CSW) in front of hyponatremia with severe hypovolemia after a brain injury, and at the same time the interest to differentiate between Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH) and Cerebral salt wasting syndrome (CSW) as two etiologies to be evoked in front of a hyponatremia with brain injury.

Case report: We report the case of a 63-year-old patient with a recent history of hemorrhagic stroke admitted for severe hypovolemic shock in whom the investigations find a very deep hypotonic hyponatremia secondary to a cerebral salt wasting syndrome successfully treated with fludrocortisone.

Discussion: CWS is characterized by hypotonic hyponatremia associated with cerebral associated with hypovolemia, the difficulty of the diagnosis is explained by the points of convergences with SIADH which is also presented with hyponatremia. The treatment is based on filling with saline, if the symptoms are severe, hypertonic saline has its place. Fludrocortisone has proven its effectiveness in the correction of refractory hyponatremia in CWS.

Conclusion: It is essential to differentiate between hyponatremia in CWS and hyponatremia in SIADH because the medical care is categorically different.

Frequency of Hyponatremia in Patients of Tuberculosis Bacterial Meningitis in a Tertiary Care Hospital

Introduction Tuberculous meningitis (TBM) brings significant morbidity and mortality worldwide. Hyponatremia has long been documented as a potentially grave metabolic result of TBM. The syndrome of inappropriate antidiuretic hormone (SIADH) secretion has been supposed to be accountable for the majority of cases of hyponatremia in TBM. Cerebral salt wasting syndrome (CSWS) is being progressively reported as a basis of hyponatremia in some of these cases. Differentiating CSWS from SIADH can be challenging but is vital because treatment of these two conditions is profoundly different. Objective The rationale of our study is to determine the frequency of hyponatremia and etiology in patients presenting with TBM in a tertiary care hospital in order to establish the local perspective as there is paucity of local data. Methods A total of 160 hospitalized patients at a tertiary care hospital in Pakistan who fulfilled the inclusion criteria were enrolled in this study after informed consent. The study was conducted for six months at the department of neurology, Jinnah Postgraduate Medical Centre (JPMC), Karachi, Pakistan. Brief history was taken and demographic information was entered in the performa by researchers. The data was collected and analyzed on Statistical Package for Social Sciences (SPSS) version 18.0 (IBM Corp., Armonk NY, USA). Demographic data were presented as simple descriptive statistics giving mean and standard deviation for age, height, weight, GCS (Glasgow Coma Scale), serum sodium and duration of symptoms. Frequencies and percentages were calculated for categorical variables like gender, hypertension, smoking status, T2DM (Type 2 Diabetes Mellitus), BMRC (British Medical Research Council Contemporary Clinical Criteria for TBM) stage, hyponatremia, SIADH and CSWS. Effect modifiers were controlled through stratification of age, gender, hypertension, smoking status, T2DM, BMRC stage and duration of symptoms to see the effect of these on the outcome variable (hyponatremia). Quantitative data were presented as simple descriptive statistics giving mean and standard deviation and qualitative variables were presented as frequency and percentages. Post stratification chi-square test was applied with a p-value of ≤0.05 taken as significant. Results In our study, out of 160 patients with TBM, 40% (64) had hyponatremia. Moreover, 14.4% and 25.6% had SIADH and CSWS, respectively with 60% (96) of patients were male and 40% (64) were female. Mean age of patients in our study was 46.78±2.81 years. Whereas, mean duration of symptoms, serum sodium, GCS, height and weight in our study was 1.2±0.78 weeks, 128.65±7.52 mmol/L and 11.21±3.14%, 158±7.28 cm and 78.7±9.87 kg, respectively. Conclusion This study concluded that the frequency of hyponatremia among patients of TBM was significant, consistent with previous studies. Privation of proper assessment and management can lead to grave and permanent neurological consequences, as well as death. Healthcare providers should be aware of the implication of sodium deregulation among patients of TBM and differentiate between the numerous therapeutic preferences in order to advocate safe and effective treatment.

Distinguishing cerebral salt wasting syndrome and syndrome of inappropriate ADH in a patient with traumatic brain injury

A previously healthy 48-year-old woman was referred to our intensive care unit (ICU) from a neurosurgical ward due to deterioration of her conscious level. She had a road traffic accident 6 days earlier. On admission to the hospital, a brain CT demonstrated subarachnoid haemorrhage which was considered not amenable to surgical intervention. A second CT brain performed shortly after admission to ICU showed no change in comparison to the initial CT. Serum sodium level on ICU admission was 108 mEq/L; serum and urine osmolalities were 223 mOsm/kg and 438 mOsm/kg, respectively. Her hyponatraemia was initially attributed to syndrome of inappropriate antidiuretic hormone. However, a clinical impression of low volume status raised the suspicion of cerebral salt wasting syndrome. She was managed by infusion of hypertonic saline and fluids for 5 days and discharged from ICU after improvement of her conscious level and normalisation of serum sodium.

Severe symptomatic hyponatremia due to cerebral salt wasting syndrome in a patient with traumatic head injury and Dandy-Walker malformation of the brain

Cerebral salt wasting (CSW) is an uncommon cause of hyponatremia characterized by extracellular volume depletion, high urine sodium concentration and osmolality, and low serum uric acid concentration in association with central nervous system (CNS) disease. Distinguishing CSW from the syndrome of inappropriate secretion of antidiuretic hormone (SIADH), a much more common form of hyponatremia in this setting, can be challenging because both present with identical laboratory features. However, treatment of CSW and SIADH differs, making a correct diagnosis important. Here we present a case of CSW in a 75-year-old man in whom severe hyponatremia and volume depletion were discovered in the setting of traumatic head injury and Dandy-Walker malformation of the brain, a rare congenital brain malformation. Treatment with intravenous normal saline and later oral salt supplementation and fludrocortisone was successful.

Delayed Postoperative Hyponatremia Following Endoscopic Transsphenoidal Surgery for Non-Adenomatous Parasellar Tumors

Little is known about delayed postoperative hyponatremia (DPH) accompanied with transsphenoidal surgery for non-adenomatous skull base tumors (NASBTs). Consecutive data on 30 patients with parasellar NASBT was retrospectively reviewed with detailed analyses on perioperative serial sodium levels. Serological DPH (sodium ≤ 135 mmol/L) was observed in eight (27%), with four (13%) of them being symptomatic. DPH developed on postoperative day 7-12 where the mean sodium levels were 134 mmol/L (a mean of 7 mmol/L drop from the baseline) in asymptomatic and 125 mmol/L (a mean of 17.5 mmol/L drop from the baseline) in symptomatic DPH. Serological DPH was accompanied with "weight loss and hemoconcentration (cerebral salt wasting type)" in four (50%), "weight gain and hemodilution (syndrome of inappropriate antidiuretic hormone secretion type)" in three (38%), and no significant weight change in one. Intraoperative extradural retraction of the pituitary gland was the only significant factor for serological DPH (p = 0.035; odds ratio, 12.25 (95% confidence interval, 1.27-118.36)). DPH should be recognized as one of the significant postsurgical complications associated with TSS for NASBTs. Although the underlying mechanism is still controversial, intraoperative extradural compression of the pituitary gland and subsequent dysregulation of the hypothalamo-hypophyseal axis may be responsible.

Hyponatremia in Patients with Hematologic Diseases

Hyponatremia is the most common electrolyte disorder in clinical practice and is associated with increased morbidity and mortality. It is frequently encountered in hematologic patients with either benign or malignant diseases. Several underlying mechanisms, such as hypovolemia, infections, toxins, renal, endocrine, cardiac, and liver disorders, as well as the use of certain drugs appear to be involved in the development or the persistence of hyponatremia. This review describes the pathophysiology of hyponatremia and discusses thoroughly the contributing factors and mechanisms that may be encountered specifically in patients with hematologic disorders. The involvement of the syndrome of inappropriate antidiuretic hormone (SIADH) secretion and renal salt wasting syndrome (RSWS) in the development of hyponatremia in such patients, as well as their differential diagnosis and management, are also presented. Furthermore, the distinction between true hyponatremia and pseudohyponatremia is explained. Finally, a practical algorithm for the evaluation of hyponatremia in hematologic patients, as well as the principles of hyponatremia management, are included in this review.

Tubercular meningitis presenting as cerebral salt wasting syndrome in an adult: A case report

Introduction

Cerebral salt wasting syndrome (CSWS) is a cause of hyponatremia in the setting of intracranial pathologies such as Central Nervous System (CNS) trauma, infections, and tumors. It is important to differentiate CSWS from the syndrome of inappropriate antidiuretic hormone secretion (SIADH) as their management differs. CSWS leads to hypovolemia as opposed to euvolemia or hypervolemia in SIADH. SIADH is managed with fluid restriction and this could worsen CSWS which is managed with adminstration of intravenous crystalloids to correct hyponatremia.

Case summary

A 42-year-old male was admitted after a week of low-grade fever with easy fatigability, hypersomnolence, and excessive thirst. He had polyuria which started 5 days before presentation, and unintentionally lost 3 kg of weight in the past month. He had orthostatic hypotension, and was dehydrated, but vital signs were normal with the exception of his temperature. Cerebrospinal fluid (CSF) analysis revealed a glucose of 42 mg/dl, protein 170 mg/dl, cell count 28/mm³ with 65% lymphocytes which was consistant with tubercular meningitis. CSF AFB culture was positive in addition to a positive CSF PCR for M. tuberculosis.

Discussion

Presentation of CNS infection with tuberculosis may be non-specific and its insidious onset could lead to delayed or missed diagnosis; however persistent constitutional symptoms and signs with history of weight loss and a close contact with tuberculosis may raise the possibility of tuberculosis. Early diagnosis and treatment has an excellent prognosis, but any delay contributes to death and disability despite anti-tubercular drug therapy.CSWS should be managed with salt and volume replacement, but more importantly, the causative CNS insult should also be confirmed and addressed.

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Presentation of tubercular meningitis may be non-specific and its insidious onset could lead to delayed or missed diagnosis.

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CSWS is characterized by hyponatremia along with increased urinary sodium excretion and extracellular volume contraction.

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Early diagnosis and treatment has an excellent prognosis, but any delays contribute to death and disability despite of ATT in patient with tubercular meningitis.

Management of Intracranial Pressure Part II: Nonpharmacologic Interventions

Pharmacologic and nonpharmacologic interventions are available to treat patients who experience serious elevations in intracranial pressure (ICP). In some cases, patients may experience ICP that is refractory to treatment. Significant negative effects on cerebral blood flow, tissue oxygenation, and cerebral metabolism occur as a result of intracranial hypertension, leading to secondary brain injury. In part 2 of this series, nonpharmacologic interventions for ICP and ICP refractory to treatment are discussed. Interventions include neurologic monitoring (bedside assessment and multimodal monitoring), ventilatory support, fluid and electrolyte maintenance, targeted temperature management, and surgical intervention. Technology is always evolving, and the focus of multimodal monitoring here includes devices to monitor ICP, brain tissue oxygen tension, and cerebral blood flow and cerebral microdialysis monitors. Nursing care of these patients includes perspicacious assessment and integration of data, monitoring ventilatory and hemodynamic functioning, and appropriate patient positioning. Nurses must collaborate with the interprofessional care team to ensure favorable patient outcomes while utilizing an evidence-based guideline for the management of ICP.

Effects of oxytocin administration on the hydromineral balance of median eminence-lesioned rats

In the clinical setting, acute injuries in hypothalamic mediobasal regions, along with polydipsia and polyuria, have been observed in patients with cerebral salt wasting (CSW). CSW is also characterised by hypovolaemia and hyponatraemia as a result of an early increase in natriuretic peptide activity. Salt and additional amounts of fluid are the main treatment for this disorder. Similarly, experimental lesions to these brain regions, which include the median eminence (ME), produce a well-documented neurological model of polydipsia and polyuria in rats, which is preceded by an early sodium excretion of unknown cause. In the present study, oxytocin (OT) was used to increase the renal sodium loss and prolong the hydroelectrolyte abnormalities of ME-lesioned animals during the first few hours post-surgery. The objective was to determine whether OT-treated ME-lesioned animals increase their sodium appetite and water intake to restore the volume and composition of extracellular body fluid. Electrolytic lesion of the ME increased water intake, urinary volume and sodium excretion of food-deprived rats and also decreased urine osmolality and estimated plasma sodium concentration. OT administration at 8 hours post-surgery reduced water intake, urine output and plasma sodium concentration and also increased urine osmolality and urine sodium excretion between 8 and 24 hours post-lesion. From 24 to 30 hours, more water and hypertonic NaCl was consumed by OT-treated ME-lesioned rats than by physiological saline-treated-ME-lesioned animals. Food availability from 30 to 48 hours reduced the intake of hypertonic saline solution by ME/OT animals, which increased their water and food intake during this period. OT administration therefore appears to enhance the natriuretic effect of ME lesion, producing hydroelectrolyte changes that reduce the water intake of food-deprived animals. Conversely, the presence of hypertonic NaCl increases the fluid intake of these animals, possibly as a result of the plasma sodium depletion and hypovolaemic states previously generated. Finally, the subsequent increase in food intake by ME/OT animals reduces their need for hypertonic NaCl but not water, possibly in response to osmotic thirst. These results are discussed in relation to a possible transient activation of the ME with the consequent secretion of natriuretic peptides stored in terminal swellings, which would be augmented by OT administration. Electrolytic lesion of the ME may therefore represent a useful neurobiological model of CSW.

Clinical Spectrum of Hyponatremia in Patients with Stroke

Introduction

Hyponatremia is a common electrolyte imbalance, which is readily observed in patients with ischemic as well as hemorrhagic stroke. It is mostly hypoosmolal and may be due to syndrome of inappropriate anti-diuretic hormone (SIADH) or cerebral salt wasting syndrome (CSWS). The aim of this study was to evaluate the clinical spectrum of hyponatremia in patients of both hemorrhagic and ischemic strokes.

Methods

In this prospective observational study, all patients admitted with stroke were screened for serum sodium levels right after hospital admission. Patients with serum sodium levels <135 mEq/L were included. Their demographic characteristics, type of stroke, etiology of hyponatremia, and site of hemorrhage/vascular territory ischemia was included.

Results

Hyponatremia was diagnosed in 34.2% of patients. Their mean serum sodium level was 130.4 ± 3.5 (mEq/L). Ischemic stroke was more common in the hyponatremia group (67.7%), and SIADH was a more common cause of hyponatremia (71.1%). In hyponatremic patients with hemorrhagic stroke, right putamen hemorrhage was seen in 50% of patients with SIADH, and right thalamus was seen in 73.3% patients with CSWS. In hyponatremic patients with ischemic stroke, left middle cerebral artery ischemia was seen in 47% patients with SIADH and right middle cerebral artery ischemia was seen in 55% patients with CSWS.

Conclusion

In patients with hyponatremia secondary to stroke, ischemic stroke is a common entity. SIADH remains a more frequently witnessed underlying pathology in hyponatremic stroke patients.

Posterior pituitary dysfunction following traumatic brain injury: review

Neurohypophysial dysfunction is common in the first days following traumatic brain injury (TBI), manifesting as dysnatremia in approximately 1 in 4 patients. Both hyponatremia and hypernatremia can impair recovery from TBI and in the case of hypernatremia, there is a significant association with excess mortality. Hyponatremia secondary to syndrome of inappropriate antidiuretic hormone secretion (SIAD) is the commonest electrolyte disturbance following TBI. Acute adrenocorticotropic hormone (ACTH)/cortisol deficiency occurs in 10-15% of TBI patients and can present with a biochemical picture identical to SIAD. For this reason, exclusion of glucocorticoid deficiency is of particular importance in post-TBI SIAD. Cerebral salt wasting is a rare cause of hyponatremia following TBI. Hyponatremia predisposes to seizures, reduced consciousness, and prolonged hospital stay. Diabetes insipidus (DI) occurs in 20% of cases following TBI; where diminished consciousness is present, appropriate fluid replacement of renal water losses is occasionally inadequate, leading to hypernatremia. Hypernatremia is strongly predictive of mortality following TBI. Most cases of DI are transient, but persistent DI is also predictive of mortality, irrespective of plasma sodium concentration. Persistent DI may herald rising intracranial pressure due to coning. True adipsic DI is rare following TBI, but patients are vulnerable to severe hypernatremic dehydration, exacerbation of neurologic deficits and hypothalamic complications, therefore clinicians should be aware of this possible variant of DI.

Chronic hyponatremia in a patient with renal salt wasting and without cerebral disease: relationship between RSW, risk of fractures and cognitive impairment

Renal salt wasting syndrome (RSW) is defined as a renal loss of sodium leading to hyponatremia and a decrease in extracellular fluid volume (ECV). Differentiation of this disorder from the syndrome of inappropriate antidiuretic hormone secretion (SIADH), a common cause of hyponatremia, can be difficult because both can present with hyponatremia and concentrated urine with natriuresis. Our clinical case about a 78-year-old woman with a recent fracture of the right femur not only confirms that this syndrome can occur in patients without intracranial pathologies (CT documented), but depicts how the hyponatremia caused by RSW can show a chronic, oscillating course. This is an interesting point of view because it suggests to us to consider RSW in the differential diagnosis of patients with chronic hyponatremia.

Early Effects of Enteral Urea on Intracranial Pressure in Patients With Acute Brain Injury and Hyponatremia

BACKGROUND

Hyponatremia occurs commonly after acute brain injury and is often due to the syndrome of inappropriate antidiuretic hormone secretion (SIADH). Urea administration is 1 therapeutic option.

METHODS

In our Department, enteral urea is routinely administered to patients with acute brain injury who develop hyponatremia consistent with SIADH and do not respond to an initial sodium load. We reviewed the records of all patients over a 2-year period, who had acute brain injury, received enteral urea because of hyponatremia, and had intracranial pressure (ICP) monitoring using an intraventricular catheter. We recorded demographic, biological, and clinical data; mean ICP values during the 6 hours before and after the first dose of urea were also recorded.

RESULTS

We included 40 patients (23 subarachnoid hemorrhage, 8 traumatic brain injury, 6 intracranial hemorrhage, 2 postbrain tumor surgery, and 1 ischemic stroke); median age was 54 years (IQRs, 44 to 63 y) and median admission APACHE II score was 19 (13 to 19); 6-month survival was 63%. Median baseline sodium was 133 mEq/L (131 to 135 mEq/L). No patients received additional therapy to decrease ICP during the 6 hours following urea initiation. After the first urea dose (15 g), ICP decreased from 14 (13 to 18 mm Hg) to 11 mm Hg (8 to 13 mm Hg) (P<0.001). Changes in ICP were not correlated to changes in sodium (r=0.02). The reduction in ICP was larger in patients with ICP≥15 mm Hg (n=22) than in the others (-8 mm Hg [-14 to -3 mm Hg] vs. -2 mm Hg [-3 to 0 mm Hg], P=0.001).

CONCLUSIONS

Enteral urea administration in patients with acute brain injury and hyponatremia is associated with a significant reduction in ICP independent of changes in sodium levels.

Mild water restriction with or without urea for the longterm treatment of syndrome of inappropriate antidiuretic hormone secretion (SIADH): Can urine osmolality help the choice?

BACKGROUND

Treatment options for chronic SIADH include water restriction (WR) and urea. The usefulness of urine osmolality to guide the choice of the treatment option is not clearly defined. We hypothesized that urine osmolality can indicate whether treatment with mild water restriction alone could be successful.

METHODS

Retrospective Review of clinical and biochemical (blood and urine) data of patients with chronic SIADH treated for at least one year with mild WR (1.5-2l/day) either with or without urea.

RESULTS

Twenty nine patients were included. Nine patients were treated by mild WR. Mean serum sodium (SNa) and mean Uosm were 129±2mEq/l and 274±78mOsm/kgH2O respectively before WR, and increased to 138.5±3mEq/l and 505±87mOsm/kgH₂O (P<0.001). Eight patients were treated with mild WR and 15g urea daily, the SNa and Uosm before treatment were 127.5±3mEq/l and 340±100mOsm/kgH₂O respectively and increased to 136.5±1mEq/l and 490±151mOsm/kgH₂O (P<0.001). Four of the eight patients had a permanent low solute intake which contributed to hyponatremia. Twelve patients needed 30g urea daily combined with mild WR. The SNa and Uosm were respectively 126±2mEq/l and 595±176mOsm/kgH₂O and increased to 136.5±2mEq/l and 698±157mOsm/kgH₂O (P<0.05). Uosm increased in most of the treated patients.

CONCLUSIONS

About 30% of patients could be treated by moderate WR alone. All these patients presented an initial urine osmolality lower than 400mOsm/kgH₂O.

Mycoplasma pneumoniae- associated encephalitis complicated by cerebral salt wasting syndrome

Cerebral salt wasting syndrome can occur in children with encephalitis. Clinicians should be aware of hyponatremia in patients who develop polyuria with the signs of dehydration and deteriorated consciousness. Furthermore, patients who present with status epilepticus or who are suspected to have high intracranial pressure may have an increased risk of cerebral salt wasting syndrome.

Cerebral salt wasting syndrome in patients with minor head trauma - two case reports

We describe two polytrauma patients without severe head trauma who developed Cerebral Salt Wasting Syndrome (CSWS) during their stay in our ICU with natriuresis, hyponatremia and hypovolemia. Hyponatremia encountered in CSWS and the syndrome of inadequate antidiuretic hormone secretion (SIADH) is a common electrolyte finding in patients with severe head trauma, subarachnoid hemorrhage, malignancy and infections of the central nervous system. CSWS was an unexpected electrolyte finding in our patients with minor head trauma without neurological or neurosurgical problems. To rule out other causes of hyponatremia (SIADH, secondary adrenal dysfunction and thyroid dysfunction) a correct diagnosis is very important, as proper treatment of CSWS with fluid and salt replacement will decrease mortality and morbidity. In conclusion, CSWS should be suspected in any polytrauma patient with minor head trauma and hyponatremia.

Concurrence of Inappropriate Antidiuretic Hormone Secretion and Cerebral Salt Wasting Syndromes after Traumatic Brain Injury

Syndrome of inappropriate antidiuretic hormone (SIADH) and cerebral salt wasting syndrome (CSWS) as the two most common neuroendocrine diseases, have been recognized and understood by many neurologists. Although SIADH and CSWS are the common causes of central hyponatremia after traumatic brain injury (TBI), a few cases are mixed, with the coexistence of the two pathological pathomechanism. However, the mixed type of both SIADH and CSWS has not been clearly reported in any literature. Here, we present the first description of the concurrent syndrome of SIADH and CSWS after TBI in four patients who underwent standard diagnostic procedures, treatment and follow up. Our findings further support that this rare neuroendocrine disease may exist in clinical practice, in which the traditional-conventional treatment shows poor efficacy.

Electrolyte Disturbances in Critically Ill Cancer Patients: An Endocrine Perspective

Electrolyte disturbances are frequently encountered in critically ill oncology patients. Hyponatremia and hypernatremia as well as hypocalcemia and hypercalcemia are among the most commonly encountered electrolyte abnormalities. In the intensive care unit, management of critical electrolyte disturbances is focused on initial evaluation and immediate treatment plan to prevent severe complications. A PubMed search was performed to identify best available evidence for evaluation and management of dysnatremias, hypocalcemia, and hypercalcemia. Current literature was reviewed regarding the management of electrolyte disturbances. The role of new therapeutic options, for example, vaptans for hyponatremia, teriparatide for hypocalcemia, and denosumab for hypercalcemia, is discussed. Early diagnosis and appropriate management are expected to reduce adverse outcomes.

A Study of Hyponatremia in Acute Encephalitis Syndrome: A Prospective Study From a Tertiary Care Center in India

PURPOSE:

To evaluate the frequency and causes of hyponatremia in acute encephalitis syndrome (AES) and its effect on outcome.

PATIENTS AND METHODS:

Consecutive patients with AES were subjected to neurological evaluation including Glasgow Coma Scale, focal weakness, movement disorder, and reflex changes. The etiology of AES was based on blood and cerebrospinal fluid enzyme-linked immunosorbent assay and polymerase chain reaction. We have categorized patients into neurological or systemic AES. Hyponatremia was diagnosed if 2 consecutive serum sodium levels were below 135 mEq/L, 24 hours apart. Serum and urinary osmolality and electrolytes were measured on alternate days. Fluid intake, output, and body weight were measured daily. The hyponatremia was categorized into syndrome of inappropriate secretion of antidiuretic hormone (SIADH), cerebral salt wasting (CSW), or miscellaneous group. Outcome at 1 month was assessed by modified Rankin scale.

RESULTS:

Of 79 patients, 34 had neurologic AES and 45 had systemic AES; 22 (27.8%) patients had hyponatremia. The neurologic AES as compared to systemic AES was more commonly associated with hyponatremia (38.2% vs 20%, P = .07), need longer hospitalization (25.0 vs 12.5 days, P = .003), and longer time for sodium correction (13.3 vs 8.2 days, P = .05). The hyponatremia was due to CSW in 12 patients, SIADH in 2 patients, and indeterminate in 8 patients. Thirty-six patients had poor outcome (15 died) and 43 had good outcome which was not related to hyponatremia.

CONCLUSION:

Hyponatremia occurs in one-third of patients with AES, being commoner in neurologic AES, and CSW is the commonest cause.

Cerebral Salt-Wasting Syndrome Caused by Minor Head Injury

A 34-year-old woman was admitted to hospital after sustaining a head injury in a motor vehicle accident (day 1). No signs of neurological deficit, skull fracture, brain contusion, or intracranial bleeding were evident. She was discharged without symptoms on day 4. However, headache and nausea worsened on day 8, at which time serum sodium level was noted to be 121 mEq/L. Treatment with sodium chloride was initiated, but serum sodium decreased to 116 mEq/L on day 9. Body weight decreased in proportion to the decrease in serum sodium. Cerebral salt-wasting syndrome was diagnosed. This case represents the first illustration of severe hyponatremia related to cerebral salt-wasting syndrome caused by a minor head injury.

Cerebral Salt-wasting Syndrome and Inappropriate Antidiuretic Hormone Syndrome after Subarachnoid Hemorrhaging

Hyponatremia is a common finding after subarachnoid hemorrhaging (SAH) and can be caused by either cerebral salt-wasting syndrome (CSWS) or syndrome of inappropriate antidiuretic hormone (SIADH). Distinguishing between these two entities can be difficult because they have similar manifestations, including hyponatremia, serum hypo-osmolality, and high urine osmolality. We herein report the case of a 60-year-old man who suffered from SAH complicated by hyponatremia. During his initial hospitalization, he was diagnosed with CSWS. He was readmitted one week later with hyponatremia and was diagnosed with SIADH. This is the first report of SAH causing CSWS followed by SIADH. These two different sources of hyponatremia require different treatments.

Post-cytokine-release Salt Wasting as Inverse Tumor Lysis Syndrome in a Non-cerebral Natural Killer-cell Neoplasm

The pathogenesis of cerebral/renal salt-wasting syndrome remains unknown. We herein present a case of salt-wasting syndrome with a natural killer-cell neoplasm without cerebral invasion. A 78-year-old man with hemophagocytic syndrome received two cycles of chemotherapy that did not induce tumor lysis syndrome, but repeatedly caused polyuria and natriuresis. The expression of tumor necrosis factor-α in the neoplasm led us to hypothesize that an oncolysis-induced cytokine storm may have caused renal tubular damage and salt wasting. Our theory may explain the pathogenic mechanism of cerebral/renal salt-wasting syndrome associated with other entities, including cerebral disorders, owing to the elevation of cytokine levels after subarachnoid hemorrhage.

SODIUM AND WATER IMBALANCE AFTER SELLAR, SUPRASELLAR, AND PARASELLAR SURGERY

OBJECTIVE

To report the frequency of sodium and water disturbances (SWDs) in patients undergoing sellar, suprasellar, and parasellar surgery (SSPS).

METHODS

We conducted a cross-sectional, retrospective study on 115 patients in the Aga Khan University Hospital after ethical approval. Patients were 16 years old or older undergoing pituitary or sellar surgeries. We collected data on basic sociodemographic characteristics and clinical indication for surgery. We noted laboratory values for serum electrolytes, plasma and urine osmolality, urine sodium, and 24-hour fluid balance from the immediate postoperative day until discharge and follow-up. We recorded medical management plans. We also recorded diabetes insipidus (DI), syndrome of inappropriate antidiuretic hormone (SIADH), cerebral salt wasting (CSW), triphasic response, and hyponatremia, according to the diagnostic definitions. Finally, we performed data analysis using Statistical Package for the Social Sciences, version 19.0.

RESULTS

Of 115 patients, there were 61.7% males, mean age 42.3 ± 13.86 years, 91.3% had pituitary adenoma (73.0% nonfunctioning), and 86.1% underwent transsphenoidal surgical approach. Transient DI occurred from days 1 to 6, peaking with 57.4% on day 2. Permanent DI and SIADH were rare. We did not note typical triphasic response or CSW in any of the patients. However, isolated hyponatremia occurred in 11%, and 20.9% had DI with hyponatremia.

CONCLUSION

Transient DI is the most common postoperative SWD after SSPS. Hyponatremia occurred alone and following DI. This is the first study describing postoperative SWDs after different sellar surgeries in Pakistan.

ABBREVIATIONS

ADH = antidiuretic hormone CSW = cerebral salt wasting DI = diabetes insipidus SIADH = syndrome of inappropriate antidiuretic hormone SSPS = sellar, suprasellar, and parasellar surgery SWD = sodium and water disturbance.

A 5-Year-Old With Fever, Headache, Neck Stiffness, and Leg Pain

A 5-year-old boy presented with fever, headache, fatigue, neck stiffness, and 2 episodes of nocturnal urinary incontinence, prompting a visit to the emergency department. He had experienced intermittent frontal headaches and leg and buttock pain for several months, which had worsened over the previous 2 weeks. His history was notable for a spinal hemangioma with vascular tract, but he was otherwise healthy. On examination, he was febrile and tachycardic. He held his neck slightly rotated to the right with limited range of motion in all directions due to pain. No focal neurologic deficits were noted, and sensation and deep tendon reflexes were intact bilaterally. He was able to bear weight on both legs. There was no spinal tenderness or limitation in range of motion of his back and hips. There were no cutaneous manifestations, including no sacral dimple. A complete blood count with differential revealed leukocytosis of 31.98 × 103/µL (78.6% neutrophils, 16% bands). C-reactive protein was elevated at 2.4 mg/dL (0-1 mg/dL), and serum electrolytes, liver function tests, uric acid, and lactate dehydrogenase were within normal limits for age. Blood cultures were obtained before admission. Here we present his case, diagnostic evaluation, ultimate diagnosis, and complications.

Cerebral salt-wasting syndrome in a child with Wernicke encephalopathy treated with fludrocortisone therapy: A case report

RATIONALE FOR THIS CASE REPORT

Cerebral Salt-Wasting Syndrome (CSWS) is characterized by hyponatremia and sodium wasting in the urine. These conditions are triggered by various neurosurgical disorders such as subarachnoid hemorrhage, brain tumor, head injury, and brain surgery. To our knowledge, CSWS caused by Wernicke encephalopathy (WE) has been rarely reported.

PRESENTING CONCERNS OF THE PATIENT

A 2-year-old male patient presented to our hospital due to a seizure attack. He had been neglected and refused to take food for a long time (body weight < 3rd percentile). During admission, the patient showed low serum osmolality, high urine osmolality, dehydration state, increased urine output, and negative water balance, a diagnosis of CSWS was made.

DIAGNOSES, INTERVENTIONS, AND OUTCOMES

Brain MRI displayed symmetrical lesions of T2WI and FLAIR high signal intensity in the peri-aqueductal and hypothalamic areas, which suggests Wernicke encephalopathy. For the early diagnosis of WE, neuroimaging studies can be an important marker. Thiamine hydrochloride was administered at a dose of 100 mg/day for 3 weeks. Cerebral salt-wasting syndrome was subsequently diagnosed due to persistent hyponatremia, dehydrated state, and high urine sodium with massive urination.

MAIN LESSONS LEARNED FROM THIS CASE

Wernicke encephalopathy is a very rare cause of cerebral salt-wasting syndrome in pediatrics patients. The patient had a good outcome after hypertonic solution and fludrocortisone therapy.

Syndrome of inappropriate secretion of antidiuretic hormone (SIADH) associated with lateral medullary syndrome: case report and literature review

Background

Only one case of syndrome of inappropriate secretion of antidiuretic hormone with lateral medullary syndrome has been reported so far. We report a case of lateral medullary syndrome showing syndrome of inappropriate secretion of antidiuretic hormone and analyze the pathomechanism underlying its clinical features.

Case presentation

A 67-year-old man was admitted to our hospital for dizziness, dysarthria, and dysphagia. He was diagnosed with lateral medullary syndrome based on the neurological examination and brain magnetic resonance imaging. Horner syndrome was absent. Asymptomatic hyponatremia appeared 9 days after admission and the patient was diagnosed with syndrome of inappropriate secretion of antidiuretic hormone. Fluid restriction and intravenous furosemide injection improved the hyponatremia.

Conclusion

Lateral medullary syndrome could be associated with syndrome of inappropriate secretion of antidiuretic hormone.

Atrial natriuretic factor: is it responsible for hyponatremia and natriuresis in neurosurgery?

Objective

To evaluate the presence of hyponatremia and natriuresis and their association with atrial natriuretic factor in neurosurgery patients.

Methods

The study included 30 patients who had been submitted to intracranial tumor resection and cerebral aneurism clipping. Both plasma and urinary sodium and plasma atrial natriuretic factor were measured during the preoperative and postoperative time periods.

Results

Hyponatremia was present in 63.33% of the patients, particularly on the first postoperative day. Natriuresis was present in 93.33% of the patients, particularly on the second postoperative day. Plasma atrial natriuretic factor was increased in 92.60% of the patients in at least one of the postoperative days; however, there was no statistically significant association between the atrial natriuretic factor and plasma sodium and between the atrial natriuretic factor and urinary sodium.

Conclusion

Hyponatremia and natriuresis were present in most patients after neurosurgery; however, the atrial natriuretic factor cannot be considered to be directly responsible for these alterations in neurosurgery patients. Other natriuretic factors are likely to be involved.

Cerebral Salt Wasting Syndrome following Head Injury in a Child Managed Successfully with Fludrocortisone

Cerebral salt wasting (CSW) syndrome is an important cause of hyponatremia in head injuries apart from syndrome of inappropriate antidiuretic hormone (SIADH). Proper diagnosis and differentiation between these two entities are necessary for management as the treatment is quite opposite in both conditions. Fludrocortisone can help in managing CSW where alone saline infusion does not work. We report a 17-month-old female child with head injury managed successfully with saline infusion and fludrocortisone.

Ten common pitfalls in the evaluation of patients with hyponatremia

Hyponatremia is the most common electrolyte disorder in hospitalized patients associated with increased morbidity and mortality. On the other hand, inappropriate treatment of hyponatremia (under- or mainly overtreatment) may also lead to devastating consequences. The appropriate diagnosis of the causative factor is of paramount importance for the proper management and avoidance of treatment pitfalls. Herein, we describe the most common pitfalls in the evaluation of the hyponatremic patient, such as failure to exclude pseudohyponatremia or hypertonic hyponatremia (related to glucose, mannitol or glycine), to properly assess urine sodium concentration and other laboratory findings, to diagnose other causes of hyponatremia (cerebral salt wasting, reset osmostat, nephrogenic syndrome of inappropriate antidiuresis, prolonged strenuous exercise, drugs) as well as inability to measure urine osmolality or delineate the diagnosis and cause of the syndrome of inappropriate antidiuretic hormone secretion. Clinicians should be aware of these common clinical practice pitfalls, which could endanger patients with hyponatremia.

Etiology of postoperative hyponatremia following pediatric intracranial tumor surgery

OBJECT Cerebral salt wasting (CSW) and the syndrome of inappropriate antidiuretic hormone secretion (SIADH) cause postoperative hyponatremia in neurosurgery patients, can be difficult to distinguish clinically, and are associated with increased morbidity. The authors aimed to determine risk factors associated with CSW and SIADH among children undergoing surgery for intracranial tumors. METHODS This retrospective cohort study included children 0-19 years of age who underwent a first intracranial tumor surgery with postoperative hyponatremia (sodium ≤ 130 mEq/L). CSW was differentiated from SIADH by urine output and fluid balance, exclusive of other causes of hyponatremia. The CSW and SIADH groups were compared with basic bivariate analysis and recursive partitioning. RESULTS Of 39 hyponatremic patients, 17 (44%) had CSW and 10 (26%) had SIADH. Patients with CSW had significantly greater natriuresis compared with those with SIADH (median urine sodium 211 vs 28 mEq/L, p = 0.01). Age ≤ 7 years and female sex were significant risk factors for CSW (p = 0.03 and 0.04, respectively). Both patient groups had hyponatremia onset within the first postoperative week. Children with CSW had trends toward increased sodium variability and symptomatic hyponatremia compared with those with SIADH. Most received treatment, but inappropriate treatment was noted to worsen hyponatremia. CONCLUSIONS The authors found that CSW was more common following intracranial tumor surgery and was associated with younger age and female sex. Careful assessment of fluid balance and urine output can separate patients with CSW from those who have SIADH, and high urine sodium concentrations (> 100 mEq/L) support a CSW diagnosis. Patients with CSW and SIADH had similar clinical courses, but responded to different interventions, making appropriate diagnosis and treatment imperative to prevent morbidity.

Hyponatremia in Neurotrauma: The Role of Vasopressin

Hyponatremia is frequent in patients suffering from traumatic brain injury, subarachnoid hemorrhage, or following intracranial procedures, with approximately 20% having a decreased serum sodium concentration to <125 mmol/L. The pathophysiology of hyponatremia in neurotrauma is not completely understood, but in large part is explained by the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). The abnormal water and/or sodium handling creates an osmotic gradient promoting the shift of water into brain cells, thereby worsening cerebral edema and precipitating neurological deterioration. Unless hyponatremia is corrected promptly and effectively, morbidity and mortality increases through seizures, elevations in intracranial pressure, and/or herniation. The excess mortality in patients with severe hyponatremia (<125 mmol/L) extends beyond the time frame of hospital admission, with a reported mortality of 20% in hospital and 45% within 6 months of follow-up. Current options for the management of hyponatremia include fluid restriction, hypertonic saline, mineralocorticoids, and osmotic diuretics. However, the recent development of vasopressin receptor antagonists provides a more physiological tool for the management of excess water retention and consequent hyponatremia, such as occurs in SIADH. This review summarizes the existing literature on the pathophysiology, clinical features, and management of hyponatremia in the setting of neurotrauma.

Cerebral salt-wasting syndrome after hematopoietic stem cell transplantation in adolescents: 3 case reports

Cerebral salt-wasting syndrome (CSWS) is a rare disease characterized by a extracellular volume depletion and hyponatremia induced by marked natriuresis. It is mainly reported in patients who experience a central nervous system insult, such as cerebral hemorrhage or encephalitis. The syndrome of inappropriate antidiuretic hormone secretion is a main cause of severe hyponatremia after hematopoietic stem cell transplantation, whereas CSWS is rarely reported. We report 3 patients with childhood acute leukemia who developed CSWS with central nervous system complication after hematopoietic stem cell transplantation. The diagnosis of CSW was made on the basis of severe hyponatremia accompanied by increased urine output with clinical signs of dehydration. All patients showed elevated natriuretic peptide and normal antidiuretic hormone. Aggressive water and sodium replacement treatment was instituted in all 3 patients and 2 of them were effectively recovered, the other one was required to add fludrocortisone administration.

Cerebral salt wasting after traumatic brain injury: a review of the literature

Electrolyte imbalances are common among patients with traumatic brain injury (TBI). Cerebral salt wasting (CSW) is an electrolyte imbalance characterized by hyponatremia and hypovolemia. Differentiating the syndrome of inappropriate antidiuretic hormone and CSW remains difficult and the pathophysiological mechanisms underlying CSW are unclear. Our intent was to review the literature on CSW within the TBI population, in order to report the incidence and timing of CSW after TBI, examine outcomes, and summarize the biochemical changes in patients who developed CSW. We searched MEDLINE through 2014, hand-reviewed citations, and searched abstracts from the American Association for the Surgery of Trauma (2003-2014). Publications were included if they were conducted within a TBI population, presented original data, and diagnosed CSW. Publications were excluded if they were review articles, discussed hyponatremia but did not differentiate the etiology causing hyponatremia, or presented cases with chronic disease. Fifteen of the 47 publications reviewed met the selection criteria; nine (60%) were case reports, five (33%) were prospective and 1 (7%) was a retrospective study. Incidence of CSW varied between 0.8 - 34.6%. The populations studied were heterogeneous and the criteria used to define hyponatremia and CSW varied. Though believed to play a role in the development of CSW, increased levels of natriuretic peptides in patients diagnosed with CSW were not consistently reported. These findings reinforce the elusiveness of the CSW diagnosis and the need for strict and consistent diagnostic criteria.

Water and electrolyte disorders at long-term post-treatment follow-up in paediatric patients with suprasellar tumours include unexpected persistent cerebral salt-wasting syndrome

BACKGROUND

Patients with brain tumours have a high risk of water and electrolyte disorders (WED). Postsurgery diabetes insipidus (DI) may be transient or permanent, the syndrome of inappropriate antidiuretic hormone secretion (SIADH) and cerebral salt-wasting syndrome (CSWS) are usually transient.

METHODS

Retrospective study, including patients with suprasellar tumours, treated at Hôpital Necker, Institut Gustave-Roussy or Institut Curie, in Île-de-France, between 2007 and 2011. WED were noted if they persisted >1 month after surgery.

RESULTS

159 patients were included, 54.1% girls, 43.9% boys. Tumour types were: glioma (43.4%), craniopharyngioma (43.4%), germinoma (11.3%), others (1.9%). Age at diagnosis was 7.1 ± 4.6 years. The median time from end of treatment was 1.9 (0-7.8) years. DI was the most frequent disorder after tumour treatment (50.3%) and was significantly associated with surgery (p < 0.001). Persistent CSWS was present in 3.6%, persistent SIADH in 1.3%. Two cases of hypernatraemia were due to adipsia. Thyrotropin deficiency after treatment was noted in 68.9% of patients tested, adrenocorticotropin deficiency in 66.2%.

CONCLUSIONS

Patients with suprasellar tumours have a high incidence of long-term WED, mainly DI. Assessment of thyrotroph and corticotroph function, and thirst sensation, is necessary to diagnose and manage these disorders correctly. CSWS may be persistent in few patients and requires special attention to prescribe the appropriate care.

Neurosurgical Hyponatremia

Hyponatremia is a frequent electrolyte imbalance in hospital inpatients. Acute onset hyponatremia is particularly common in patients who have undergone any type of brain insult, including traumatic brain injury, subarachnoid hemorrhage and brain tumors, and is a frequent complication of intracranial procedures. Acute hyponatremia is more clinically dangerous than chronic hyponatremia, as it creates an osmotic gradient between the brain and the plasma, which promotes the movement of water from the plasma into brain cells, causing cerebral edema and neurological compromise. Unless acute hyponatremia is corrected promptly and effectively, cerebral edema may manifest through impaired consciousness level, seizures, elevated intracranial pressure, and, potentially, death due to cerebral herniation. The pathophysiology of hyponatremia in neurotrauma is multifactorial, but most cases appear to be due to the syndrome of inappropriate antidiuretic hormone secretion (SIADH). Classical treatment of SIADH with fluid restriction is frequently ineffective, and in some circumstances, such as following subarachnoid hemorrhage, contraindicated. However, the recently developed vasopressin receptor antagonist class of drugs provides a very useful tool in the management of neurosurgical SIADH. In this review, we summarize the existing literature on the clinical features, causes, and management of hyponatremia in the neurosurgical patient.

Symptomatic hyponatremia following lateral medullary infarction: a case report

BACKGROUND

Hyponatremia has been reported from patients with severe neurological disease, and the syndrome of inappropriate secretion of antidiuretic hormone and cerebral salt wasting syndrome are the two main etiologies of hyponatremia after brain injury. Here we describe a patient with a lateral medullary infarction who experienced symptomatic hyponatremia with finding suggestive of syndrome of inappropriate secretion of antidiuretic hormone followed by cerebral salt wasting syndrome.

CASE PRESENTATION

A 70-year-old Korean man visited emergency room complaining of sudden onset vertigo and gait disturbance. Neurological exam showed left side ataxia, Horner syndrome, and right side hypesthesia. Brain magnetic resonance imaging disclosed acute infarction involving left lateral medulla. His neurological status was stabilized, but he began to complain of non-vertiginous dizziness and general weakness five days after admission. Serum sodium level dropped from 131 mEq/mL to 122 mEq/mL with reduced serum osmolarity of 265 mOsm/L. The diagnosis of syndrome of inappropriate secretion of antidiuretic hormone was made and we restricted fluid intake, but his symptoms worsened and his mental status became drowsy. Follow up serum sodium level was 108 mEq/L with volume loss, suggesting cerebral salt wasting syndrome. We treated him with hypertonic saline and his consciousness was recovered.

CONCLUSION

This case shows symptomatic hyponatremia after lateral medullary infarction, providing insight about distinct pathogenesis of syndrome of inappropriate secretion of antidiuretic hormone and cerebral salt wasting syndrome.

Multiple electrolyte disorders in a neurosurgical patient: solving the rebus

BACKGROUND

It is important to ensure an adequate sodium and volume balance in neurosurgical patients in order to avoid the worsening of brain injury.Indeed, hyponatremia and polyuria, that are frequent in this patient population, are potentially harmful, especially if not promptly recognized.Differential diagnosis is often challenging, including disorders, which, in view of similar clinical pictures, present very different pathophysiological bases, such as syndrome of inappropriate antidiuresis, cerebral/renal salt wasting syndrome and diabetes insipidus.

CASE PRESENTATION

Here we present the clinical report of a 67-year-old man with a recent episode of acute subarachnoid haemorrhage, admitted to our ward because of severe hyponatremia, hypokalemia and huge polyuria.We performed a complete workup to identify the underlying causes of these alterations and found a complex picture of salt wasting syndrome associated to primary polydipsia. The appropriate diagnosis allowed us to correct the patient hydro-electrolyte balance.

CONCLUSION

The comprehension of the pathophysiological mechanisms is essential to adequately recognize and treat hydro-electrolyte disorders, also solving the most complex clinical problems.