Posterior Reversible Encephalopathy Syndrome in a Patient With Primary Hyperaldosteronism (Conn Syndrome)

Posterior reversible encephalopathy syndrome (PRES) is an uncommon manifestation of severe hypertension. PRES most commonly manifests with headache, confusion, and vision loss, and typically, these symptoms are reversible (1).

Clinical Correspondence Section Editors: Robert Avery, DO Karl C. Golnik, MD Caroline Froment, MD, PhD An-Guor Wang, MD Posterior Reversible Encephalopathy Syndrome in a Patient With Primary Hyperaldosteronism (Conn Syndrome) Amir Ali, BSA, Subahari Raviskanthan, MBBS, Peter W. Mortensen, MD, Andrew G. Lee, MD P osterior reversible encephalopathy syndrome (PRES) is an uncommon manifestation of severe hypertension. PRES most commonly manifests with headache, confusion, and vision loss, and typically, these symptoms are reversible (1). We present a case of a patient with chronic poorly controlled hypertension in whom PRES was the initial presentation that prompted evaluation for secondary hypertension due to primary hyperaldosteronism (i.e., Conn syndrome). The patient had a right homonymous hemianopsia due to ischemic infarct after PRES. To the best of our knowledge, this is the first case of homonymous hemianopsia as a primary manifestation of Conn syndrome to be reported in the English language ophthalmic literature. A 61-year-old African American man presented to the emergency department with acute headache and visual loss. He had prior refractory hypertension since his thirties, type 2 diabetes mellitus, hypercholesterolemia, stage 3 chronic kidney disease, obesity, and prostate cancer requiring prostatectomy and radiation therapy. Surgical history was significant for type B aortic dissection requiring previous thoracic endovascular aortic repair and subsequent descending thoracic aneurysm repair. His medications included aspirin, amiloride, clonidine, metoprolol, spironolactone, potassium tablets, tadalafil, fesoterodine, magnesium, and a multivitamin. He did not smoke or drink alcohol. The School of Medicine (AA), University of Texas Medical Branch, Galveston, Texas; Department of Ophthalmology (SR, PM, AGL), Blanton Eye Institute, Houston Methodist Hospital, Houston, Texas; Departments of Ophthalmology (AGL), Neurology, and Neurosurgery, Weill Cornell Medicine, New York, New York; Department of Ophthalmology (AGL), University of Texas Medical Branch, Galveston, Texas; University of Texas MD Anderson Cancer Center (AGL), Houston, Texas; Texas A and M College of Medicine (AGL), Bryan, Texas; and Department of Ophthalmology (AGL), the University of Iowa Hospitals and Clinics, Iowa City, Iowa. The authors report no conflicts of interest. All named authors meet the International Committee of Medical Journal Editors (ICMJE) criteria for authorship for this article, take responsibility for the integrity of the work as a whole, and have given their approval for this version to be published. Address correspondence to Andrew G. Lee, MD, Department of Ophthalmology—Blanton Eye Institute, Houston Methodist Hospital, 6560 Fannin St. Ste 450 Houston, TX 77030; E-mail: aglee@ houstonmethodist.org Ali et al: J Neuro-Ophthalmol 2023; 43: e9-e11 patient’s blood pressure in the emergency department was 217/124 mm Hg. There were no neurological signs on initial examination. He was admitted to the intensive care unit and commenced on intravenous nicardipine, labetalol, and clonidine. Initial computed tomography (CT) of the brain was unremarkable. Four days into his admission, the patient developed acute confusion, gait disturbance, and urinary incontinence. Neurological assessment at this time revealed impaired attention, right-left confusion, and bilateral dysmetria. No vision abnormalities were noted. Repeat cranial CT and MRI in week 1 showed restricted diffusion, indicating cytotoxic edema, in the splenium of the corpus callosum on diffusion-weighted imaging (DWI). Serial MRI scans over the next month showed rapid progression of these diffusion restricting lesions into the posterior callosal body and bilateral parietal lobes with involvement of the subcortical U fibers. He also developed new nondiffusion restricting T2 fluid-attenuated inversion recovery (FLAIR) lesions in the caudate nuclei bilaterally and the left globus pallidum, suggestive of some vasogenic rather than cytotoxic edema. Of note, the diffusion restriction was maximal at the borders of the progressive lesions, more suggestive of a toxic/metabolic/hypertensive etiology. During this time, there was no significant worsening of his clinical features. Poor renal function precluded the use of gadolinium contrast. Further workup for causes of secondary hypertension revealed plasma renin level 0.09 ng/mL/ hour (normal 0.25–5.82), aldosterone 54 ng/dL (normal ,28), and potassium ranging between 2.8 and 3.1 mEq/ L (normal 3.5–5.1). An abdominal CT revealed a left 1.8 · 2.2-cm adrenal lesion. Adrenal venous sampling could not be performed, and he underwent laparoscopic left adrenalectomy. Catheter angiogram did not reveal renal artery stenosis. Infectious workup was negative, and lumbar puncture was unremarkable. A trial of intravenous methylprednisolone was given 3 months into the presentation because of ongoing fluctuating neurological symptoms without any improvement. Four months after the initial presentation, the patient was referred for neuroophthalmic assessment for continued vision deficits, which he had been reporting since admission. On examination, his visual acuity was 20/50 in the right eye and 20/80 in the e9 Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited. Clinical Correspondence FIG. 1. Automated visual fields showing right homonymous hemianopsia—4 months after initial presentation. left eye. He read 5/14 Ishihara plates in each eye. The pupils were isocoric and reactive to light OU, with no relative afferent pupillary defect. External examination was normal. Automated visual field revealed a dense right homonymous hemianopsia with superimposed superior and inferior loss in the right eye and in the left eye (Fig. 1). Dilated fundus examination revealed marked arteriolar narrowing, resolving hemorrhages, and cotton wool spot consistent with grade III hypertensive retinopathy. Repeat MRI of the brain and orbit without contrast showed scattered subcortical and deep white matter T2/FLAIR hypertense signal abnormalities, involving the bilateral periventricular parietal lobes, and likely a left lateral geniculate nucleus lesion, with resulting encephalomalacia and gliosis (Fig. 2). DWI and gradient-related echo (GRE) MRI sequences were normal. Neuro-ophthalmic follow-up 3 months later was stable. Overall, his symptoms fit with PRES as a first presentation of primary hyperaldosteronism with ongoing right homonymous hemianopsia. PRES is a clinicalradiological condition that has multiple causes including severe hypertension, kidney disease, immunosuppressive therapies, and malignancy. Despite the name, the syndrome is not always posterior, may not be reversible, and may not be associated with encephalopathy (2). Clinical symptoms include vision abnormalities, encephalopathy, headache, and seizures, which typically resolve after a mean of 5.3 days (1). Radiological features on T2 images indicate focal vasogenic and cytotoxic edema, hemorrhage, and ischemia (1,3). PRES lesions may show restricted diffusion on DWI (suggestive of cytotoxic edema), nonrestricted diffusion on DWI (vasogenic edema), T2 FLAIR lesions, or any combination of these radiographic findings. GRE may also show hemorrhages (4). Our patient had many of the typical features of PRES, including acutely altered mental state and dysmetria. His urinary incontinence may have been a feature of his confusion but has also rarely been reported in PRES. e10 He had a residual right homonymous hemianopsia (consistent with ischemic infarct after cytotoxic edema) and residual bilateral periventricular parietal lobe hyperintensities—the visual findings are more common in PRES, which often affects the occipital cortex and posterior cerebral hemispheres in preference to the anterior cortices. The prognosis for PRES is varied, and some patients die (8%–17%) or suffer irreversible neurologic findings. Patients with PRES may show complete or incomplete recovery over days (70%–90%) to months (2,4). The risk FIG. 2. MRI B T2 FLAIR showing periventricular hyperintensity and a focal hyperintense lesion around the area of the left lateral geniculate nucleus—6 months after initial presentation. Ali et al: J Neuro-Ophthalmol 2023; 43: e9-e11 Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited. Clinical Correspondence of mortality increases based on underlying etiology, increased age, high C-reactive protein, associated subarachnoid hemorrhage, altered mental status as initial presentation, and altered coagulation state (2). Predicting recovery and speed of recovery is difficult. Territorial ischemia/infarcts and cytotoxic edema with diffusion restriction on DWI MRI, as in our patient, are associated with irreversible structural brain damage, residual clinical symptoms, and poorer outcomes (2). Intracranial hemorrhage occurs in 10%–25% of PRES cases. Severe hypertension is a main risk factor for PRES and may also be correlated with atypical lesions (4). Our patient is unique because of the development of ischemic infarction and PRES due to hypertensive emergency caused by Conn syndrome (primary hyperaldosteronism). Conn syndrome may present with uncontrolled hypertension, cardiovascular complications, stroke, kidney failure, and early death (5). Clinicians should be aware of secondary causes of hypertension in patients with PRES and that such patients may present with visual complaints. To the best of our knowledge, this is the first case of Conn syndrome associated with a homonymous hemianopsia in the English language ophthalmic literature. Ali et al: J Neuro-Ophthalmol 2023; 43: e9-e11 STATEMENT OF AUTHORSHIP Conception and design: A. Ali, S. Raviskanthan, P. Mortensen, A. G. Lee; Acquisition of data: A. Ali, S. Raviskanthan, P. Mortensen, A. G. Lee; c. Analysis and interpretation of data: A. Ali, S. Raviskanthan, P. Mortensen, A. G. Lee. Drafting the manuscript: A. Ali, S. Raviskanthan, P. Mortensen, A. G. Lee; Revising it for intellectual content: A. Ali, S. Raviskanthan, P. Mortensen, A. G. Lee. Final approval of the completed manuscript: A. Ali, S. Raviskanthan, P. Mortensen, A. G. Lee. 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