Cerebral Salt-Wasting Syndrome in a Patient With Neuroleptic Malignant Syndrome

Mechanism, spectrum, consequences and management of hyponatremia in tuberculous meningitis

Hyponatremia is the commonest electrolyte abnormality in hospitalized patients and is associated with poor outcome. Hyponatremia is categorized on the basis of serum sodium into severe (< 120 mEq/L), moderate (120-129 mEq/L) and mild (130-134mEq/L) groups. Serum sodium has an important role in maintaining serum osmolality, which is maintained by the action of antidiuretic hormone (ADH) secreted from the posterior pituitary, and natriuretic peptides such as atrial natriuretic peptide and brain natriuretic peptide. These peptides act on kidney tubules via the renin angiotensin aldosterone system. Hyponatremia <120mEq/L or a rapid decline in serum sodium can result in neurological manifestations, ranging from confusion to coma and seizure. Cerebral salt wasting (CSW) and syndrome of inappropriate secretion of ADH (SIADH) are important causes of hyponatremia in tuberculosis meningitis (TBM). CSW is more common than SIADH. The differentiation between CSW and SIADH is important because treatment of one may be detrimental for the other; evidence of hypovolemia in CSW and euvolemia or hypervolemia in SIADH is used for differentiation. In addition, evidence of dehydration, polyuria, negative fluid balance as assessed by intake output chart, weight loss, laboratory evidence and sometimes central venous pressure are helpful in the diagnosis of these disorders. Volume contraction in CSW may be more protracted than hyponatremia and may contribute to border zone infarctions in TBM. Hyponatremia should be promptly and carefully treated by saline and oral salt, while 3% saline should be used in severe hyponatremia with coma and seizure. In refractory patients with hyponatremia, fludrocortisone helps in early normalization of serum sodium without affecting polyuria or functional outcome. In SIADH, V2 receptor antagonist conivaptan or tolvaptan may be used if the patient is not responding to fluid restriction. Fluid restriction in SIADH has not been found to be beneficial in TBM and should be avoided.

Mechanism, spectrum, consequences and management of hyponatremia in tuberculous meningitis

Hyponatremia is the commonest electrolyte abnormality in hospitalized patients and is associated with poor outcome. Hyponatremia is categorized on the basis of serum sodium into severe (< 120 mEq/L), moderate (120-129 mEq/L) and mild (130-134mEq/L) groups. Serum sodium has an important role in maintaining serum osmolality, which is maintained by the action of antidiuretic hormone (ADH) secreted from the posterior pituitary, and natriuretic peptides such as atrial natriuretic peptide and brain natriuretic peptide. These peptides act on kidney tubules via the renin angiotensin aldosterone system. Hyponatremia <120mEq/L or a rapid decline in serum sodium can result in neurological manifestations, ranging from confusion to coma and seizure. Cerebral salt wasting (CSW) and syndrome of inappropriate secretion of ADH (SIADH) are important causes of hyponatremia in tuberculosis meningitis (TBM). CSW is more common than SIADH. The differentiation between CSW and SIADH is important because treatment of one may be detrimental for the other; evidence of hypovolemia in CSW and euvolemia or hypervolemia in SIADH is used for differentiation. In addition, evidence of dehydration, polyuria, negative fluid balance as assessed by intake output chart, weight loss, laboratory evidence and sometimes central venous pressure are helpful in the diagnosis of these disorders. Volume contraction in CSW may be more protracted than hyponatremia and may contribute to border zone infarctions in TBM. Hyponatremia should be promptly and carefully treated by saline and oral salt, while 3% saline should be used in severe hyponatremia with coma and seizure. In refractory patients with hyponatremia, fludrocortisone helps in early normalization of serum sodium without affecting polyuria or functional outcome. In SIADH, V2 receptor antagonist conivaptan or tolvaptan may be used if the patient is not responding to fluid restriction. Fluid restriction in SIADH has not been found to be beneficial in TBM and should be avoided.

Is cerebral salt wasting related to sympathetic dysregulation in tuberculous meningitis?

BACKGROUND

Cerebral Salt wasting (CSW) is common in Tuberculous Meningitis (TBM) and is suggested to be due to sympathetic dysregulation of renal blood supply but has not been proven.

OBJECTIVE

To evaluate plasma Catecholamines in TBM patients with CSW and correlate with the markers of stress.

MATERIALS AND METHODS

The diagnosis of TBM was based on clinical, CSF and MRI criteria. Catecholamines level was measured by LC-MS on admission, at the time of hyponatremia and on correction of hyponatremia. Catecholamine levels were correlated with clinical and laboratory markers of stress, hyponatremia and severity of CSW using pre-defined criteria.

RESULTS

There were 24 patients with TBM (12 with CSW) and 12 controls. The median age of patients was 31 (18-75) years and 12 (50 %) were females. TBM patients with CSW had significantly higher levels of catecholamines compared to controls (p < 0.001). TBM patients with CSW had higher levels of norepinephrine than those without CSW (p = 0.034). Sequential studies revealed that dopamine and epinephrine increased at the time of hyponatremia and declined on its correction. Severity of TBM was related to dopamine (p = 0.04) and severity of CSW was related to epinephrine (p = 0.016).

CONCLUSION

CSW in TBM seems to be related to catecholamine dysregulation.

[Symptomatic hyponatremia in a 43-year-old woman after a skiing accident with head injuries]

This article reports the case of a 43-year-old woman who presented to the emergency room with headache and paresthesia after a fall on the head while skiing. She had clinical signs of volume depletion and blood test showed severe hyponatremia. Cerebral imaging was unremarkable. The diagnosis of cerebral salt-wasting syndrome (CSWS) was made, which is defined by the presence of extracellular volume depletion due to a tubular defect in renal sodium transport in patients with normal adrenal and thyroid function. The disease is mostly secondary to a neurological disease or head trauma. The patient rapidly improved after volume therapy and treatment with mineralocorticoids. The differentiation of CSWS from the syndrome of inappropriate antidiuretic hormone (SIADH) secretion can be challenging but the distinction is important because treatment options are very different.

Diagnosis and Treatment of Cerebral Salt Wasting Syndrome With Cryptococcal Meningitis in HIV Patient

Hyponatremia is one of the most common electrolyte imbalances in HIV patients. The differential diagnosis may include hypovolemic hyponatremia, syndrome of inappropriate antidiuretic hormone secretion (SIADH), and adrenal insufficiency. Here, we describe a case of hyponatremia secondary to cerebral salt wasting syndrome (CSWS) in an HIV patient with cryptococcal meningitis. A 52-year-old man with a history of diabetes and HIV was admitted for headache and found to have cryptococcal meningitis. He was also found to have asymptomatic hyponatremia. He had signs of hypovolemia, such as orthostatic hypotension, dry mucosa, decreased skin turgor, hemoconcentration, contraction alkalosis, and high BUN/Cr ratio. The laboratory findings revealed sodium of 125 mmol/L, potassium of 5.5 mmol/L, urine osmolality of 522 mOsm/kg, urine sodium of 162 mmol/L, and urine chloride of 162 mmol/L. We started normal saline for hypovolemia, each 1 L prior and after amphotericin therapy. However, hypovolemia did not improve significantly despite IV fluid. Cosyntropin stimulation test was negative, and renin level was 0.25 ng·mL·h, with the aldosterone level of <1 ng/dL, the serum brain natriuretic peptide of 15 pg/mL, and serum uric acid of 2.8 mg/dL. The diagnosis of CSWS was suspected, fludrocortisone was tried, and hypovolemia and hyponatremia improved. Cryptococcal meningitis in HIV patients can present with CSWS, and the distinction between CSWS and SIADH is important because the treatment for CSWS is different than that of SIADH. Both share a similar clinical picture except that CSWS presents with constant hypovolemia despite volume replacement. Salt tablets, normal saline, or fludrocortisone can be used for treatment.

Cerebral salt wasting syndrome: review

Hyponatremia is the most frequent electrolyte disorder in critically neurological patients. Cerebral salt wasting syndrome (CSW) is defined as a renal loss of sodium during intracranial disease leading to hyponatremia and a decrease in extracellular fluid volume. The pathogenesis of this disorder is still not completely understood. Sympathetic responses as well as some natriuretic factors play a role in this syndrome. Distinction between SIADH and CSW might be difficult. The essential point is the volemic state. It is necessary to rule out other intermediate causes. Treatment requires volume replacement and maintenance of a positive salt balance. Mineral corticoids may be useful in complicated cases.

Syndrome de perte de sel d'origine cérébrale avec hyponatrémie au cours d'une méningite bactérienne

Subarachnoid hemorrhage is the most common cause of cerebral salt wasting syndrome. There are few reports of this condition in infectious meningitis. We describe a patient with hyponatremia and bacterial meningitis. Hyponatremia rapidly improved after administration of sodium chloride. The purpose of this report is to alert clinicians to the fact that hyponatremic patients with central nervous system disease do not necessarily have a syndrome of inappropriate secretion of antidiuretic hormone (SIADH), but may have cerebral salt wasting syndrome. By contrast with SIADH, the treatment requires saline administration.