Introduction: Hyponatremia associated with rhabdomyolysis is a rare event and a correct diagnostic approach is required to rule out this or other diseases as a primary cause and to avoid other complications resulting from a lack of appropriate treatment.
Case presentation: A 64-year-old Caucasian woman presented to our facility with worsening fatigue, slurred speech, nausea and vomiting, and high serum levels of creatine kinase and myoglobin together with hyponatremia. Normal arterial blood gas analysis results, normal serum potassium levels, increased urine sodium levels, urine specific gravity of >1003N/m3 and low urine volume suggested an endocrine etiology. Her low cortisol and thyroid hormone serum levels suggested a pituitary disorder. A magnetic resonance imaging study showed atrophy of her pituitary gland. A more detailed study of our patient's obstetric history revealed a post-partum hemorrhage 30 years earlier. She was diagnosed as having late-onset Sheehan's syndrome and treated with hormone replacement therapy, which normalized her clinical picture.
Conclusions: This case report shows that, in hyponatremia-associated rhabdomyolysis, an endocrinological origin should always be considered. This should include Sheehan's syndrome as it can occur with late onset.