Suprasellar arachnoid cyst resulting in the syndrome of inappropriate antidiuretic hormone secretion

Abstract

<jats:p>The syndrome of inappropriate antidiuretic hormone secretion (SIADH) is occasionally seen after hypothalamic injury or dysfunction, although it typically occurs in association with other endocrine disturbances. It is has never been described as a presenting feature of a suprasellar arachnoid cyst (SAC) in the pediatric population. The authors describe the case of an enlarging SAC resulting in SIADH as the only presenting feature, with an otherwise normal hypothalamic-pituitary axis.</jats:p> <jats:p>An SAC was diagnosed in utero in this 5-month-old girl who had a normal functioning hypothalamic-pituitary axis on presentation. Because of cyst enlargement and hydrocephalus, the patient was scheduled for surgery; however, preoperative labs revealed SIADH. After stabilizing the serum sodium concentration with fluid restriction and the administration of 3% sodium chloride, the patient underwent endoscopic cyst fenestration. Postoperatively, she had complete resolution of the SIADH.</jats:p> <jats:p>Syndrome of inappropriate antidiuretic hormone secretion as the presenting symptom of an SAC has not been previously described. In the aforementioned patient, the proposed mechanism for SIADH was enlargement of the suprasellar arachnoid cyst causing compression of the supraoptic and paraventricular nuclei and thus overstimulating the secretion of arginine vasopressin, which resulted in SIADH.</jats:p> <jats:p>The association of SIADH with an SAC is reportable, as is the resolution of the SIADH via cyst fenestration. The authors suggest that SIADH is an uncommon presenting feature of SACs and that syndrome resolution is possible with cyst decompression.</jats:p>

Rapid deterioration of primary fourth ventricular outlet obstruction resulting in syndrome of inappropriate antidiuretic hormone secretion

“…With immediate resolution of SIADH with resolution of intraventricular hypertension, it is important to note that SIADH could be triggered by intraventricular hypertension. SIADH in our case might also have been provoked by acute compression of the supraoptic and paraventricular nuclei because of intraventricular hypertension and acute increase in ICP.…”

“…To the best of our knowledge, only four patients with non‐tumoral hydrocephalus have been diagnosed as having SIADH prior to surgical procedures, and all of them were adult patients with NPH . SIADH is also uncommon as a presenting symptom secondary to raised pressure hydrocephalus associated with a brain tumor or cyst . This is the first report of an infant with non‐tumoral raised pressure hydrocephalus who developed SIADH.…”

“…The typical endocrine disturbances of a patient with hydrocephalus are precocious puberty and short stature . Hydrocephalus may also be the cause of syndrome of inappropriate antidiuretic hormone secretion (SIADH), but few cases have been reported . In the pediatric population, only one female infant has been reported to have SIADH as a presenting feature of a suprasellar arachnoid cyst (SAC) with hydrocephalus and the main cause of her SIADH could be enlargement of the SAC causing compression of the hypothalamus rather than hydrocephalus .…”

“…6 Hydrocephalus may also be the cause of syndrome of inappropriate antidiuretic hormone secretion (SIADH), but few cases have been reported. [7][8][9][10][11][12][13] In the pediatric population, only one female infant has been reported to have SIADH as a presenting feature of a suprasellar arachnoid cyst (SAC) with hydrocephalus and the main cause of her SIADH could be enlargement of the SAC causing compression of the hypothalamus rather than hydrocephalus. 13 We report here a previously well infant who devel-oped SIADH accompanied by rapid deterioration of symptoms of intracranial hypertension resulting from obstructive tetraventricular hydrocephalus without any underlying cause and significant malformations, except for a barely visible membranous obstacle at the foramen of Magendie in magnetic resonance imaging (MRI).…”

A case of a cerebral cavernous malformation of the third ventricle that caused the syndrome of inappropriate secretion of antidiuretic hormone

“…SIADH due to suprasellar tumors, such as Rathke's cleft cysts, craniopharyngiomas, germ cell tumors, arachnoid cysts, and pituitary adenomas, sometimes occurs before surgery, because the mass might cause inappropriate ADH release by direct mechanical stimulation and ischemic changes at the osmoreceptor and ADH-secreting neurons. [12] In our case, SIADH might have resulted from compression of the bilateral hypothalamus by rapid enlargement of the CCM due to intralesional hemorrhage, and it improved by decompression of the hypothalamus after surgery.…”