Cerebral salt wasting
- Biff F Palmer, MD
Biff F Palmer, MD
- Professor of Internal Medicine
- University of Texas Southwestern Medical Center
Hyponatremia is a common electrolyte disorder in the setting of central nervous system (CNS) disease. This is usually attributed to the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) [1-4].
Cerebral salt wasting (CSW) is another potential cause of hyponatremia in those with CNS disease, particularly patients with subarachnoid hemorrhage. CSW is characterized by hyponatremia and extracellular fluid depletion due to inappropriate sodium wasting in the urine . However, some authorities contend that CSW does not really exist and is only a misnomer for what is actually SIADH, with the putative salt wasting being due to unappreciated volume expansion [6,7].
Issues related to CSW, including the differentiation from SIADH, will be reviewed here. The causes and diagnosis of hyponatremia, causes and treatment of SIADH, and the general management of patients with subarachnoid hemorrhage are presented separately. (See "Causes of hyponatremia in adults" and "Diagnostic evaluation of adults with hyponatremia" and "Pathophysiology and etiology of the syndrome of inappropriate antidiuretic hormone secretion (SIADH)" and "Treatment of hyponatremia: Syndrome of inappropriate antidiuretic hormone secretion (SIADH) and reset osmostat" and "Treatment of aneurysmal subarachnoid hemorrhage".)
With respect to pathophysiology, two issues need to be addressed: the mechanism of salt wasting and the mechanism of hyponatremia.
The mechanism by which cerebral disease might lead to renal salt wasting is poorly understood. Two putative mechanisms are disruption of neural input to the kidney and central elaboration of a circulating natriuretic factor [8,9]:
- Hasan D, Wijdicks EF, Vermeulen M. Hyponatremia is associated with cerebral ischemia in patients with aneurysmal subarachnoid hemorrhage. Ann Neurol 1990; 27:106.
- Sherlock M, O'Sullivan E, Agha A, et al. The incidence and pathophysiology of hyponatraemia after subarachnoid haemorrhage. Clin Endocrinol (Oxf) 2006; 64:250.
- Wartenberg KE, Schmidt JM, Claassen J, et al. Impact of medical complications on outcome after subarachnoid hemorrhage. Crit Care Med 2006; 34:617.
- Qureshi AI, Suri MF, Sung GY, et al. Prognostic significance of hypernatremia and hyponatremia among patients with aneurysmal subarachnoid hemorrhage. Neurosurgery 2002; 50:749.
- Gutierrez OM, Lin HY. Refractory hyponatremia. Kidney Int 2007; 71:79.
- Singh S, Bohn D, Carlotti AP, et al. Cerebral salt wasting: truths, fallacies, theories, and challenges. Crit Care Med 2002; 30:2575.
- Carlotti AP, Bohn D, Rutka JT, et al. A method to estimate urinary electrolyte excretion in patients at risk for developing cerebral salt wasting. J Neurosurg 2001; 95:420.
- Palmer BF. Hyponatremia in patients with central nervous system disease: SIADH versus CSW. Trends Endocrinol Metab 2003; 14:182.
- Palmer BF. Hyponatraemia in a neurosurgical patient: syndrome of inappropriate antidiuretic hormone secretion versus cerebral salt wasting. Nephrol Dial Transplant 2000; 15:262.
- Al-Mufti H, Arieff AI. Hyponatremia due to cerebral salt-wasting syndrome. Combined cerebral and distal tubular lesion. Am J Med 1984; 77:740.
- Berendes E, Walter M, Cullen P, et al. Secretion of brain natriuretic peptide in patients with aneurysmal subarachnoid haemorrhage. Lancet 1997; 349:245.
- Berger TM, Kistler W, Berendes E, et al. Hyponatremia in a pediatric stroke patient: syndrome of inappropriate antidiuretic hormone secretion or cerebral salt wasting? Crit Care Med 2002; 30:792.
- Harrigan MR. Cerebral salt wasting syndrome: a review. Neurosurgery 1996; 38:152.
- Levin ER, Gardner DG, Samson WK. Natriuretic peptides. N Engl J Med 1998; 339:321.
- Steele MK, Gardner DG, Xie PL, Schultz HD. Interactions between ANP and ANG II in regulating blood pressure and sympathetic outflow. Am J Physiol 1991; 260:R1145.
- Nelson PB, Seif SM, Maroon JC, Robinson AG. Hyponatremia in intracranial disease: perhaps not the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). J Neurosurg 1981; 55:938.
- Wijdicks EF, Vermeulen M, ten Haaf JA, et al. Volume depletion and natriuresis in patients with a ruptured intracranial aneurysm. Ann Neurol 1985; 18:211.
- Levine JP, Stelnicki E, Weiner HL, et al. Hyponatremia in the postoperative craniofacial pediatric patient population: a connection to cerebral salt wasting syndrome and management of the disorder. Plast Reconstr Surg 2001; 108:1501.
- Sivakumar V, Rajshekhar V, Chandy MJ. Management of neurosurgical patients with hyponatremia and natriuresis. Neurosurgery 1994; 34:269.
- Lenhard T, Külkens S, Schwab S. Cerebral salt-wasting syndrome in a patient with neuroleptic malignant syndrome. Arch Neurol 2007; 64:122.
- Filippella M, Cappabianca P, Cavallo LM, et al. Very delayed hyponatremia after surgery and radiotherapy for a pituitary macroadenoma. J Endocrinol Invest 2002; 25:163.
- Sengupta K, Ali U, Andankar P. Cerebral salt wasting. Indian Pediatr 2002; 39:488.
- Ti LK, Kang SC, Cheong KF. Acute hyponatraemia secondary to cerebral salt wasting syndrome in a patient with tuberculous meningitis. Anaesth Intensive Care 1998; 26:420.
- Erduran E, Mocan H, Aslan Y. Another cause of hyponatraemia in patients with bacterial meningitis: cerebral salt wasting. Acta Paediatr 1997; 86:1150.
- Oster JR, Perez GO, Larios O, et al. Cerebral salt wasting in a man with carcinomatous meningitis. Arch Intern Med 1983; 143:2187.
- Ganong CA, Kappy MS. Cerebral salt wasting in children. The need for recognition and treatment. Am J Dis Child 1993; 147:167.
- Jiménez R, Casado-Flores J, Nieto M, García-Teresa MA. Cerebral salt wasting syndrome in children with acute central nervous system injury. Pediatr Neurol 2006; 35:261.
- Taplin CE, Cowell CT, Silink M, Ambler GR. Fludrocortisone therapy in cerebral salt wasting. Pediatrics 2006; 118:e1904.
- Naval NS, Stevens RD, Mirski MA, Bhardwaj A. Controversies in the management of aneurysmal subarachnoid hemorrhage. Crit Care Med 2006; 34:511.
- Wijdicks EF, Vermeulen M, Murray GD, et al. The effects of treating hypertension following aneurysmal subarachnoid hemorrhage. Clin Neurol Neurosurg 1990; 92:111.
- Maesaka JK, Imbriano LJ, Ali NM, Ilamathi E. Is it cerebral or renal salt wasting? Kidney Int 2009; 76:934.
- Maesaka JK, Venkatesan J, Piccione JM, et al. Abnormal urate transport in patients with intracranial disease. Am J Kidney Dis 1992; 19:10.
- Diringer MN, Wu KC, Verbalis JG, Hanley DF. Hypervolemic therapy prevents volume contraction but not hyponatremia following subarachnoid hemorrhage. Ann Neurol 1992; 31:543.
- Albanese A, Hindmarsh P, Stanhope R. Management of hyponatraemia in patients with acute cerebral insults. Arch Dis Child 2001; 85:246.
- Kinik ST, Kandemir N, Baykan A, et al. Fludrocortisone treatment in a child with severe cerebral salt wasting. Pediatr Neurosurg 2001; 35:216.
- Wijdicks EF, Vermeulen M, Hijdra A, van Gijn J. Hyponatremia and cerebral infarction in patients with ruptured intracranial aneurysms: is fluid restriction harmful? Ann Neurol 1985; 17:137.
- Hasan D, Lindsay KW, Wijdicks EF, et al. Effect of fludrocortisone acetate in patients with subarachnoid hemorrhage. Stroke 1989; 20:1156.
- Ishikawa SE, Saito T, Kaneko K, et al. Hyponatremia responsive to fludrocortisone acetate in elderly patients after head injury. Ann Intern Med 1987; 106:187.