Kidney Week

Abstract: FR-PO0874

Acute Hyponatremic Encephalopathy in a Healthy Young Man After Bowel Preparation

Session Information

• Fluid, Electrolyte, and Acid-Base Disorders: Case Reports - 1
  October 23, 2026 | Location: Exhibit Hall A, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Fluid, Electrolytes, and Acid-Base Disorders

• 1102 Fluid, Electrolyte, and Acid-Base Disorders: Clinical

Authors

• Jeong, Seung Hee, Presbyterian Medical Center, Jeonju-si, Jeollabuk-do , Korea (the Republic of)

Seung Hee Jeong, MD

• Oh, Ju hwan, Presbyterian Medical Center, Jeonju-si, Jeollabuk-do , Korea (the Republic of)

Ju hwan Oh, MD

• Cho, A young, Presbyterian Medical Center, Jeonju-si, Jeollabuk-do , Korea (the Republic of)

A young Cho, MD

• Sun, In O, Presbyterian Medical Center, Jeonju-si, Jeollabuk-do , Korea (the Republic of)

In O Sun, MD, PhD

• Lee, Ha-Eun, Presbyterian Medical Center, Jeonju-si, Jeollabuk-do , Korea (the Republic of)

Ha-Eun Lee, MD

Introduction

Acute hyponatremia is a potentially life-threatening medical emergency that can cause cerebral edema and severe neurologic complications. Although generally considered safe, bowel preparation has been associated with acute hyponatremic encephalopathy. Previously reported cases have predominantly involved elderly or female patients, often with comorbidities or exposure to medications predisposing to hyponatremia, such as thiazide diuretics, desmopressin, or selective serotonin reuptake inhibitors. However, its occurrence in otherwise healthy young males remains rare.

Case Description

A 37-year-old man presented to the emergency department with a generalized seizure and altered mental status during colonoscopy preparation. He had a history of dyslipidemia treated with pitavastatin/ezetimibe. On examination, the patient had stable vital signs and was euvolemic. Laboratory evaluation revealed severe hypoosmolar hyponatremia (serum sodium 120 mEq/L; osmolality 259 mOsm/kg) with preserved renal function (serum creatinine 0.6 mg/dL) (Table 1). Thyroid and adrenal function were normal. Neuroimaging and cerebrospinal fluid analyses were unremarkable. Hypertonic saline (3% NaCl) was administered, increasing serum sodium to 132 mEq/L at 14 hours and 140 mEq/L at 42 hours, with complete neurologic recovery. Further history revealed ingestion of approximately 6 L of water within 2 hours and recent loxoprofen use.

Discussion

Elderly individuals are more susceptible to hyponatremia due to reduced renal free-water clearance and increased comorbidities, and women are more susceptible due to hormonal effects and greater exposure to medications. However, in this case, acute hyponatremic encephalopathy occurred in a healthy young man. Ingestion of approximately 6 L of water within 2 hours likely exceeded renal free-water excretory capacity, leading to acute water intoxication. Concomitant non-steroidal anti-inflammatory drug (NSAID) use may have further contributed by potentiating antidiuretic hormone activity and impairing free-water clearance. Clinicians should be aware that bowel preparation-associated hyponatremia can occur in otherwise healthy young males and should provide guidance to avoid excessive fluid intake and NSAID use.