Résumé

Hyponatremia is the most frequently observed metabolic disorder, with 38% of patients experiencing an episode during their hospitalization. The neuro-intensive care patient population is particularly at risk, with a prevalence estimated at 50%. For many years, the sole explanation was syndrome of inappropriate antidiuretic hormone secretion (SIADH). First described by Peters et al. in 1950, cerebral salt wasting syndrome (CSWS) corresponds to renal sodium loss occurring during an intracranial pathology, leading to hyponatremia and a decrease in effective plasma volume. We present a case of salt wasting syndrome during bacterial meningitis occurring three days after external ventricular drainage (EVD) for a posterior fossa tumor in the neuro-intensive care unit. The patient was hospitalized for the management of intracranial hypertension. He underwent central venous drainage followed by EVD. Five days after surgery, the patient developed postoperative bacterial meningitis caused by methicillin-resistant Staphylococcus aureus (MRSA). He presented with persistent cardiovascular collapse and preload dependence, associated with polyuria and general dehydration. In addition, he had hyponatremia (116 mmol/L) with elevated 24-hour urinary sodium excretion (184 mmol/24 h). Renal function tests and ultrasound were normal. After 48 hours of treatment, the patient was placed on fluid restriction in anticipation of SIADH, but hyponatremia and hyperdiuresis persisted. A trial of hypertonic saline and hydrocortisone infusions was administered. His neurological status gradually improved, and his serum sodium level stabilized following this treatment. A diagnosis of salt-wasting syndrome was ultimately made. The patient's condition improved, with further neurological improvement.

Mot-clés :

Cerebral Salt Wasting Syndrome (Csw), Hyponatremia, Brain Natriuretic Peptide (Bnp), Meningitis, Brain Tumor