Abstract: SA-PO539
"Tubular Intoxication": Phosphatidylethanol Testing to Diagnose Alcohol-Induced Hypomagnesemia
Session Information
- Acid-Base, Calcium, Potassium, and Magnesium Disorders: Clinical
October 26, 2024 | Location: Exhibit Hall, 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
- Cima, Sophia M., University of Nebraska Medical Center College of Medicine, Omaha, Nebraska, United States
- Lowe, Aj, University of Nebraska Medical Center College of Medicine, Omaha, Nebraska, United States
- Hawkins, Jay L., University of Nebraska Medical Center, Omaha, Nebraska, United States
- Ravipati, Prasanth, University of Nebraska Medical Center, Omaha, Nebraska, United States
Introduction
Hypomagnesemia occurs with chronic alcohol (EtOH) use through multiple pathways including intestinal malabsorption, decreased dietary intake, and importantly, renal magnesium wasting. Previous data has shown that discrepancy between patient reported EtOH consumption and true EtOH intake is common. A new test, called Phosphatidylethanol (PEth), is an invaluable tool in identifying EtOH consumption patterns and alcohol-related disorders. PEth accumulates with repeat ethanol exposure, and thus, PEth reliably indicates a person’s EtOH consumption over the prior 28 days. We present a case series of 3 patients with uncertain etiology of hypomagnesemia, in which PEth testing confirmed a diagnosis of chronic EtOH consumption resulting in renal magnesium wasting.
Case Description
A 68-year-old man and 58-year-old woman were referred to nephrology clinic for hypomagnesemia refractory to supplementation. They had chronic magnesium levels of 1.2-1.4 mg/dL and 1.1-1.5 mg/dL, respectively. A 33-year-old man was admitted to the hospital due to muscle spasms and weakness and was found to have magnesium level of 0.9 mg/dL. Fractional excretion of magnesium on a random urine sample was greater than 8% in all patients. All patients had normal renal function, were without additional risk factors for renal magnesium wasting, and reported consuming less than 6 drinks per week. PEth levels (ng/mL) were 1,401, 206, 337 – indicating severe EtOH consumption (level > 200) and consistent with EtOH intake beyond the patients’ report.
Discussion
In the setting of hypomagnesemia associated with renal magnesium wasting, the differential is broad, including EtOH consumption. EtOH consumption as reported by patients can be difficult to quantify and can be misleading. With the novel use of PEth testing, these three patients were ultimately diagnosed with EtOH use disorder as the cause of their hypomagnesemia and referred to addiction services. In the evaluation of hypomagnesemia, PEth testing can help clinicians identify EtOH use disorder and help optimize management strategy, potentially reducing the need for additional work up (genetic testing, medication adjustments, additional consultations).