DÄ internationalArchive8/2026Polyuria as an Initial Manifestation of Spontaneous Intracranial Hypotension

Clinical Snapshot

Polyuria as an Initial Manifestation of Spontaneous Intracranial Hypotension

Dtsch Arztebl Int 2026; 123: 219. DOI: 10.3238/arztebl.m2026.0014

Zhong, Q; Lai, B

LNSLNS
Figure: Brain MRI revealed diffuse dural enhancement (A, arrows), forming the “Mercedes-Benz” sign. The sagittal view (B) shows pituitary engorgement with a height of approximately 9.98 mm.
Figure 1
Figure: Brain MRI revealed diffuse dural enhancement (A, arrows), forming the “Mercedes-Benz” sign. The sagittal view (B) shows pituitary engorgement with a height of approximately 9.98 mm.

A 38-year-old woman had a 20–day history of progressive polyuria. Tests excluded diabetes mellitus and insipidus. The patient subsequently developed orthostatic headache relieved in the recumbent position, along with nausea, vomiting, otalgia, and phonophobia, 5 days prior to admission. Brain MRI showed diffuse dural enhancement (Figure a), pituitary engorgement (Figure b), venous sinus distension, and bilateral frontotemporal subdural hygromas. Lumbar puncture confirmed spontaneous intracranial hypotension (SIH) with an opening pressure of 56 mmH2O. After 1 week of conservative management (bed rest, hydration), both polyuria and headache resolved completely without recurrence at 1-month follow-up. Although a published case report suggested that polyuria could cause intracranial hypotension, the simultaneous onset and resolution of polyuria with SIH in our patient supports it being a rare manifestation of the condition. We hypothesize that altered intracranial dynamics in SIH may transiently disrupt hypothalamic pituitary function. In SIH, cerebrospinal fluid loss leads to pituitary venous congestion, which in turn causes engorgement of the highly vascularized pituitary gland.

Qinglin Zhong, MD, Department of Neurosurgery, Ganzhou People‘s Hospital

Binglin Lai, MD, Ganzhou Institute of Medical Imaging, Ganzhou Key Laboratory of Medical Imaging and Artificial Intelligence, Medical Imaging Center, Ganzhou People‘s Hospital, Ganzhou Hospital-Nanfang Hospital, Southern Medical University, binglin723.lai@outlook.com

Funding: Clinical Research Center for Medical Imaging in Jiangxi Province [Grant number 20223BCG7400199].

Conflict of interest statement: The authors declare that no conflict of interest exists.

Cite this as: Zhong Q, Lai B: Polyuria as an initial manifestation of spontaneous intracranial hypotension. Dtsch Arztebl Int 2026; 123: 219a.
DOI: 10.3238/arztebl.m2026.0014