A ＂tricky＂ subarachnoid hemorrhage

To the editor： We report a tricky subarachnoid haemorrhage （SAH）. Our patient was a 59-year-old woman with generalizedheadache for 1 day, which was constricting in nature and rated grade 6/10. Her symptoms were aggravated by lying flat and improved with vomiting. The Glasgow coma scale was lull, blood pressure was 142/83 mmHg and pulse 75 beats/min. There was neither neck stiffness nor focal neurological deficit. Fundoscopic examination was normal. She was noted to have hyponatremia （sodium （Na） 122 mmol/L） with serum osmolarity 263 mmol/kg, urine osmolarity 582 mmol/kg, urine Na I 17 retool/L, nomaal thyroid stimulating hormone and cortisol level.