Hyponatremia Case Studies

In “Severe Hyponatremia Associated with Pre-Eclampsia,” published in Gynecological Endocrinology, the authors present the case of a 25-year-old pregnant woman (25 weeks gestation) who presents with “mild physical signs of edema along with hypertension, proteinuria, and a severe hyponatremia (113 mEq/L).” Her condition was diagnosed as hypervolemic hyponatremia. Labor was induced and the hyponatremia resolved within 72 hours after treatment with water restriction.

In their conclusion, the authors noted that “The pathogenesis of pre-eclampsia-associated hyponatremia is relatively unknown. A non-osmotic stimulation of vasopressin release in the setting of a hypervolemic state with low effective circulating plasma volume is thought to be the main mechanism. Advanced maternal age and nephrotic range proteinuria have been postulated as risk factors, but their causal role remains unclear. Fluid restriction is a reasonable treatment, and maternal outcomes are favorable. This condition is a rare indication for urgent delivery, but neonatal outcomes are variable.”

In “Severe Hyponatremia and MRI Point to Diagnosis of Tuberculous Meningitis in the Southwest USA,” published in BMJ Case Reports, the authors describe the case of a 21-year-old Indian woman who presented with complaints of “headache, fever, mood disturbance and nausea” lasting three days. The patient had a positive screening purified protein derivative tuberculosis skin test with normal chest x-ray and signs of meningeal irritation, which led the treating clinicians to order a lumbar puncture and start treatment for bacterial meningitis.

Although they suspected the patient might have tuberculous meningitis, the authors wrote that “the diagnosis was clouded by the rapid onset of symptoms and recent major psychosocial stressors.” The patient also subsequently developed severe hyponatremia.

A brain MRI revealed the presence of tuberculomas; a diagnosis of tuberculous meningitis was confirmed by cerebrospinal fluid culture and the patient was started on appropriate treatment.

In their review of this case, the authors observed that increasing globalization of society “makes uncommon diagnoses present in unlikely locations.” They also noted that hyponatremia is a common complication associated with tuberculous meningitis, and that while cognitive and mood changes can indicate the presence of tuberculous meningitis, an MRI can aid in diagnosis of this condition.