Severe Hypermagnesemia with Normal Renal Function Can Improve with Symptomatic Treatment

Case Reports in Emergency Medicine
20 Nov, 2020 ,

Yoshiaki Ishida et.al. presented a case of a 56-year-old woman presented with a history of constipation in spite of taking constipation medicine, including MgO. She was brought to our emergency department due to vomiting and diffuse distension of the abdomen. Sudden vomiting, weakness, and lower level of consciousness occurred during examination. Her blood pressure dropped to 77/34 mmHg, and deep tendon reflexes of the limbs disappeared. Abdominal computed tomography showed bowel distension with wall edema, and biochemical testing showed serum Mg at 13.5 mg/dl. She was diagnosed with severe hypermagnesemia associated with intestinal obstruction and administered intravenous loop diuretics and calcium preparation in addition to high volumes of normal saline. 

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A 56-year-old woman presented with an 8-day history of constipation. She had been in a support facility for individuals with disabilities for many years due to Down's syndrome. She was brought to our emergency department (ED) due to vomiting and diffuse distension of the abdomen.

She had a history of chronic constipation and had taken pharmacotherapies for constipation, including MgO at 1500 mg/day. Physical examination of the abdomen revealed only nontender distension and tympanic sounds on percussion.

Sudden vomiting, weakness, and reduced level of consciousness occurred during abdominal X-ray. While vital signs had been normal on arrival at our ED, her blood pressure dropped to 77/34 mmHg. She also showed a change to absence of deep tendon reflexes of the limbs. Electrocardiography showed a prolonged QT interval, abdominal X-ray showed accumulation of intestinal gas, and abdominal computed tomography showed bowel distension with wall edema.

Biochemical testing showed the following: glucose, 135 (73–109) mg/dl; albumin, 3.0 (4.1–5.1) mg/dl; blood urea nitrogen, 18 (8–20) mg/dl; creatinine (Cr), 0.76 (0.46–0.79) mg/dl; estimated glomerular filtration rate (eGFR), 61 ml/min/1.73 m2; calcium, 9.2 (8.7–10.3) mg/dl; and Mg, 13.5 (1.8–2.4) mg/dl.

From the above, she was diagnosed with severe hypermagnesemia associated with intestinal obstruction. Although we consulted with her family to explore the option of emergency hemodialysis, they instead decided to continue symptomatic treatment. Intravenous loop diuretics and calcium preparation bolus were administered while infusing high volumes of normal saline. She subsequently showed good diuresis and a large amount of defecation the next day. Serum Mg level steadily declined, reaching 7.3 mg/dl after 11 h, 3.6 mg/dl after 21 h, and 2.9 mg/dl after 27 h. By day 3, serum Mg level had almost normalized, at 2.5 mg/dl.

 As serum Mg level declined, her level of consciousness returned to usual. Eventually, she could walk unaided and was discharged on hospital day 15 with no sequelae.