Cerebral salt-wasting syndrome (CSWS) is a medical entity that leads to hyponatremia and hypovolemia due to dehydration, as a result of an acute or chronic and persistent underlying CNS disorder, including trauma, tumors, and other pathologies.

Patients present with the clinical manifestations of hyponatremia and hypovolemia. In general, a case of very mild hyponatremia tends to produce no noticeable symptoms; however, it has been observed that even non-severe hyponatremia can lead to devastating clinical manifestations [1]. A serum sodium concentration lower than 135 mEq/L, but over 115 mEq/L usually leads to nausea and malaise. Values less than 135 mEq/L lead to profound neurological symptomatology due to cerebral edema, including a diminished level of consciousness and lethargy, cephalalgia, epileptic phenomena and, eventually, even a comatose state [2]. There is a positive correlation between the decrease in sodium levels and the aggravation of symptoms: as the concentration of sodium in the serum of the patient declines, symptoms are exacerbated.

Hypovolemia leads to symptoms that entail dried mucous membranes (oral or nasal cavity), dry skin that lacks elasticity, sunken anterior fontanelle, and tachycardia. Profound hypovolemia causes hypotension. A vital clinical characteristic of patients affected by cerebral salt-wasting syndrome is that the aforementioned manifestations tend to respond positively to volume and sodium replacement [3] [4]. Massive polyuria that can be reversed with the simultaneous administration of vasopressin and cortisone acetate, hypotension, the absence of cardiac symptoms and hypovolemia, constitute a potential clinical picture of a patient with central diabetes insipidus and CSWS, according to a recent study [5].

• Weight Loss

  Significant Weight Loss Weight loss is often used as a surrogate for malnutrition. [northshore.org]

  In CSW, expect signs and symptoms of dehydration, including dry mucous membranes, poor skin turgor, tachycardia, orthostatic hypotension, weight loss, and a negative fluid balance (with output exceeding intake). [americannursetoday.com]

  She had a history of significant weight loss for the last six months. On examination she was drowsy and on admission Glasgow coma scale was 7/15. [jpma.org.pk]

  Intravascular volume depletion Historical features suggesting hypovolemia include thirst, abrupt weight loss, decreasing urinary frequency, and negative fluid balance. 11. [slideshare.net]

  A 6-month-old girl presented with low grade continuous fever, weight loss (one month), and right focal seizure. She was exclusively breast fed. Her father was receiving treatment for pulmonary tuberculosis. [annalsofian.org]

• Epilepsy

  The Dysautonomia Center PubMed Health-Familial Dysautonomia Panayiotopoulos Syndrome Panayiotopoulos Syndrome is also known as Autonomic Epilepsy or Benign Childhood Autonomic Epilepsy. [dysautonomiainternational.org]

  Occurrence of acute hyponatremia (48 h or less) can cause neurogenic pulmonary edema, cerebral infarction, shortness of breath, epilepsy, brain herniation, even death [ 8 ]. [omicsonline.org]

  Ketogenic diet A ketogenic diet has been well established as an effective alternative treatment for some cases of epilepsy and has gained popularity for use in conjunction with standard treatments for glioblastoma. [northshore.org]

• Diarrhea

  Other symptoms frequently associated with dysautonomia include headaches, pallor, malaise, facial flushing, constipation or diarrhea, nausea, acid reflux, visual disturbances, numbness, nerve pain, trouble breathing, chest pain, loss of consciousness, [en.wikipedia.org]

  Diarrhea Drink plenty of fluids to replace those lost from diarrhea, including water, ginger ale, and sports drinks. Let carbonated drinks lose their fizz before you drink them. Eat foods and liquids that are high in sodium and potassium. [northshore.org]

• Orthostatic Hypotension

  He had signs of hypovolemia, such as orthostatic hypotension, dry mucosa, decreased skin turgor, hemoconcentration, contraction alkalosis, and high BUN/Cr ratio. [ncbi.nlm.nih.gov]

  Advanced symptoms include muscle cramps, lightheadedness, dizziness or vertigo, feelings of anxiety or panic, increased heart rate or slowed heart rate, low blood pressure and orthostatic hypotension which can result in fainting. [en.wikipedia.org]

  But now when you assess him, you find that he can't follow simple commands, has orthostatic hypotension, and is oliguric with dry mucous membranes. [journals.lww.com]

  In CSW, expect signs and symptoms of dehydration, including dry mucous membranes, poor skin turgor, tachycardia, orthostatic hypotension, weight loss, and a negative fluid balance (with output exceeding intake). [americannursetoday.com]

  Commonly used signs of hypovolaemia include orthostatic tachycardia or hypotension, increased capillary refill time, increased skin turgor, dry mucous membranes and a sunken anterior fontanel. [jnaccjournal.org]

• Confusion

  This syndrome is often confused with dilutional hyponatremia secondary to inappropriate ADH secretion. Accurate diagnosis and management are mandatory for to improve the course of the disease. [ncbi.nlm.nih.gov]

  In this article, it was aimed to report a patient with CSWS which progresses with low percentage in intensive care unit patients with head trauma, is frequently confused with inappropriate antidiuretic hormone syndrome and progresses mortally when not [ingentaconnect.com]

  Hyponatremia signs and symptoms—confusion, lethargy, decreased level of consciousness, seizures, and coma—are common, too. [americannursetoday.com]

  On july 9th he became confused. Cerebral CT was performed with no significant changes. His natremia dropped to 128 mEq/l, with development of poliuria despite maintenance of desmopressin doses. [endocrine-abstracts.org]

• Seizure

  She presented 16 days postoperatively, and following two grand mal seizures was found to be profoundly hyponatraemic (sodium 101 nmol/l). [ncbi.nlm.nih.gov]

  The typical patient does not "convulse" as seen in grand mal seizures. The child is awake, able to speak and may vomit or feel like he is going to vomit. Sometimes the child is arisen from sleep during the seizure. [dysautonomiainternational.org]

  Hypo¬natremia also raises the seizure risk, so take appropriate seizure precautions. Also keep suction set up in the patient’s room. For better visual monitoring, the patient may need to be moved to a visible area on the unit. [americannursetoday.com]

• Lethargy

  Values less than 135 mEq/L lead to profound neurological symptomatology due to cerebral edema, including a diminished level of consciousness and lethargy, cephalalgia, epileptic phenomena and, eventually, even a comatose state. [symptoma.com]

  Hyponatremia signs and symptoms—confusion, lethargy, decreased level of consciousness, seizures, and coma—are common, too. [americannursetoday.com]

  Symptoms include lethargy, agitation, headache, altered consciousness, seizures,and coma. The severity of symptoms typically reflects the magnitude and rapidity of the decrease in serum sodium concentration. [slideshare.net]

  Symptoms include lethargy, agitation, headache, altered consciousness, seizures and coma. [17], [18] Serum osmolality Normal serum osmolality is 285-295 mosmosm/L. This is found to be decreased in SIADH but is either normal or decreased in CSWS. [jnaccjournal.org]

• Slurred Speech

  speech, somnolence, syncope, and even aggravation of their underlying disease ( 6, 12, 28, 29 ). [cjasn.asnjournals.org]

• Somnolence

  […] severe RSW to treat an erroneous diagnosis of SIADH has been reported to lead to an array of clinical consequences of ECV depletion that include weakness, loss of appetite, severe postural hypotension, disturbances in gait and mentation, slurred speech, somnolence [cjasn.asnjournals.org]

CSWS is a syndrome difficult to diagnose, due to the lack of a specific set of tests to detect any pathognomonic result. The primary difficulty is its differentiation from the syndrome of inappropriate antidiuretic hormone secretion (SIADH), due to a significant similarity between these two distinct entities. The workup involved in the diagnostic procedure encompasses:

Serum sodium concentration

Reveals hyponatremia, namely a serum sodium concentration < 135 mEq/L.

Urinary output

CSWS is expected to lead to increased urine flow and dilute urine, whereas SIADH leads to a low urine flow and concentrated urine.

Urinary sodium concentration

CSWS leads to a high urinary sodium concentration, that exceeds 40 mEq/L, followed by a negative net sodium balance.

Uric acid

Fractional excretion of uric acid (FEUA) is increased in patients with the cerebral salt-wasting syndrome and hyperuricemia is detected. These findings tend to remain, despite the reversion or hyponatremia. On the contrary, the same findings that are observed in SIADH tend to regress after the correction of serum sodium [6] [7].

Phosphate

Cerebral salt-wasting syndrome leads to an increase in the fractional excretion of phosphate (FEP), in contradistinction to SIADH [7].

• Decreased Central Venous Pressure

  A review of renal/CSWS reveals three studies involving hyponatremic neurosurgical patients who had decreased blood volume, decreased central venous pressure, and inappropriately high urinary sodium concentrations in the majority of them, suggesting that [ncbi.nlm.nih.gov]

• Hyponatremia

  The appropriate treatment of CSW syndrome is opposite the usual treatment of hyponatremia caused by SIADH. [ncbi.nlm.nih.gov]

• Hypertriglyceridemia

  Pseudohyponatremia Before the development of methods to directly measure electrolytes, falsely low sodium values could be obtained in the setting of hypertriglyceridemia, which results in the displacement of the aqueous phase from a given volume of serum [clinicaladvisor.com]

Treatment of cerebral salt wasting consists of hydration and salt replacement. This article uses a case report to discuss the importance of recognition of this syndrome, and treatment concerns are reviewed. [ncbi.nlm.nih.gov]

This case emphasizes the poor prognosis that may result from the rapid correction of profound hyponatraemia. [ncbi.nlm.nih.gov]

Objectives INTRODUCTION Definition PATHOPHYSIOLOGY Etiology EPIDEMIOLOGY History Physical Examination Workup DIAGNOSIS DIFFERENTIAL DIAGNOSIS TREATMENT Prognosis SUMMARY 3. [slideshare.net]

As long as accurate and timely diagnosis, appropriate treatment, the prognosis is good. About CSWS pathogenesis remains to be further studied. [omicsonline.org]

The report included 81 individuals with tuberculous meningitis, 39.5% of whom suffered ischemic stroke; 50% of these stroke patients had cerebral salt wasting. [12] Prognosis Cerebral salt-wasting syndrome usually develops in the first week following [emedicine.medscape.com]

The etiology of this hyponatremia is often diagnosed as syndrome of inappropriate diuretic hormone (SIADH). Fluid restriction is usually the first line of treatment. However, this can exacerbate vasospasm and produce resultant ischemia. [ncbi.nlm.nih.gov]

(See Pathophysiology, Etiology, and Presentation.) [emedicine.medscape.com]

Objectives INTRODUCTION Definition PATHOPHYSIOLOGY Etiology EPIDEMIOLOGY History Physical Examination Workup DIAGNOSIS DIFFERENTIAL DIAGNOSIS TREATMENT Prognosis SUMMARY 3. [slideshare.net]

Kojima et al have described an animal model of cerebral salt-wasting syndrome that may allow better clarification of the condition’s etiology. [8] Epidemiology Occurrence in the United States Exact incidence data for this disorder are not available. [emedicine.medscape.com]

Role of nutritional status in predicting quality of life outcomes in cancer--a systematic review of the epidemiological literature. Nutr J 11: 27, 2012. [northshore.org]

All 3 syndromes affect both sodium and water balance; however, they have differences in pathophysiology, diagnosis, and treatment. [ncbi.nlm.nih.gov]

Differences in the pathophysiology of this disorder mandate a unique therapeutic approach which may be essential to avoiding serious electrolyte disturbances. [nature.com]

PATHOPHYSIOLOGY The SNS promotes Na˖, uric acid &water reabsorption in the proximal tubule, as well as renin release. [slideshare.net]

(See Pathophysiology, Etiology, and Presentation.) [emedicine.medscape.com]

[…] the prevention of hyponatremia in hospitalized patients with CNS disease and a more hypertonic fluid may be required. [ncbi.nlm.nih.gov]

1. Grant P, Ayuk J, Bouloux PM, et al. The diagnosis and management of inpatient hyponatraemia and SIADH. Eur J Clin Invest. 2015 Aug; 45(8): 888–894.
2. Sherlock M, O'Sullivan E, Agha A, et al. Incidence and pathophysiology of severe hyponatraemia in neurosurgical patients. Postgrad Med J. 2009 Apr. 85(1002):171-5.
3. Cerdà-Esteve M, Cuadrado-Godia E, Chillaron JJ, et al. Cerebral salt wasting syndrome: review. Eur J Intern Med 2008; 19: 249–54
4. El-Amin Abdel-Latif M, Chan PWK, Yu-Teik Goh A, Chai-See Lum L. Cerebral salt wasting syndrome following atlantoaxial fracture dislocation in Down syndrome. BMJ Case Rep. 2009.
5. Wu X, Zhou X, Gao L, et al. Diagnosis and Management of Combined Central Diabetes Insipidus and Cerebral Salt Wasting Syndrome After Traumatic Brain Injury. World Neurosurg. 2016 Apr. 88:483-7.
6. Moritz ML. Syndrome of inappropriate antidiuresis and cerebral salt wasting syndrome: are they different and does it matter?. Pediatr Nephrol. 2012 May. 27(5):689-93. [Medline].
7. Maesaka JK, Miyawaki N, Palaia T, Fishbane S, Durham JH. Renal salt wasting without cerebral disease: diagnostic value of urate determinations in hyponatremia. Kidney Int. 2007 Apr. 71(8):822-6.