This 34‐year‐old woman presented with an 8‐month history of frequent emergency department visits related to episodically severe and progressively frequent nausea, vomiting, and abdominal pain. She had no neurological symptoms at the time. Despite of extensive diagnostic tests and procedures, the etiology of the bouts remained elusive. She was treated empirically for gastritis and irritable bowel syndrome, but her symptoms persisted and worsened. She eventually presented obtunded (a Glasgow Coma Scale of 10) with acute decompensated hydrocephalus that occurred after exploratory abdominal laparoscopy. Emergent ventriculostomy was performed to relieve intracranial pressure. She recovered back to her baseline within a day. Further cranial MRI evaluation demonstrated a cystic tumor in the fourth ventricle with the associated obstructive hydrocephalus. She subsequently underwent a suboccipital craniotomy for a gross total tumor resection. Intraoperatively, the tumor mass was noted to adhere to the area postrema (AP). The diagnosis of neurenteric cyst (NC) was confirmed with histological examination. Her symptoms of nausea, vomiting, and abdominal pain were all resolved on postoperative day 1. She was discharged home in 5 days uneventfully. No recurrent symptoms were reported on her one‐year follow‐up visit.
Intracranial NCs are benign, rare lesions of the central nervous system that most typically present with headache, mass effect, or location‐specific symptoms. They most frequently occur in the spinal cord, followed by infratentorial, then supratentorial locations. The majority of NCs are infratentorial. Total surgical resection is strongly recommended for NCs. The AP is a sensory circumventricular organ associated with the fourth ventricle, first associated with nausea and vomiting in the 1940s/'50s. Compared with other brain regions, the AP is highly vascularized. Those vessels are characterized by a leaky fenestrated epithelium and blood‐filled Virchow–Robin spaces, enabling the neurons of the region to monitor the chemical composition of the peripheral bloodstream. Further, the AP has both afferent and efferent projections to other brain stem nuclei, most significantly the nucleus of the solitary tract and parabrachial nuclei, suggesting that it may be not only a sensory organ but also may play a role in integrating brain stem autonomic regulation and gustatory sensation.
We describe an uncommon presentation of an already rare central nervous system cyst. The AP has few associated published case studies — the presentation of our patient may be relevant to understanding lesions of the AP in future patients. Our case also serves as a reminder to consider a neurological etiology for common and nonspecific symptoms that lack an alternative explanation. One of the medical challenges illustrated by this case is the need to define when, in the context of nonspecific symptoms such as nausea and vomiting, a neurological etiology should be considered.
To cite this abstract:Miller C, Wang B, Wang H. Neurenteric Cyst of the Area Postrema — a Case Report. Abstract published at Hospital Medicine 2013, May 16-19, National Harbor, Md. Abstract 274. Journal of Hospital Medicine. 2013; 8 (suppl 2). https://www.shmabstracts.com/abstract/neurenteric-cyst-of-the-area-postrema-a-case-report/. Accessed April 21, 2019.