A unique presentation of hyponatremia and seizures in a 2-month-old child with cystic fibrosis: a case report

Cystic fibrosis is an autosomal recessive disorder that causes a broad range of clinical findings and can present unusually as electrolyte disturbance, such as hyponatremia that causes seizures in children. CASE PRESENTATION: We report a case of a 2-month-old infant who presented with an episode of grand mal seizure induced by hyponatremia and moderate episodes of milky vomiting after breastfeeding. CLINICAL DISCUSSION: Proper investigations showed normal cardiac and renal functions. Ultrasonography showed no pathological changes. Laboratory tests performed showed hyponatremia, mild hypokalemia, and hypochloremia. Urinary electrolyte results were normal. While broadening the scope of differential diagnosis in order to reach a final diagnosis, the sweat chloride level was elevated, which confirmed the diagnosis of cystic fibroses. CONCLUSION: We aim to share our case to keep cystic fibroses in mind as a differential diagnosis when dealing with hyponatremic seizures in children.