Endocrine Abstracts

64 years old lady with history of breast cancer (post lumpectomy followed by radical mastectomy) received chemotherapy with Epirvlacin 140 mg and cyclophosphamide 600 mg 1 day prior. Past medical history included hypertension on ramipril and type 2 diabetes on diet control. Bloods on day of chemotherapy normal particularly sodium 135 mmols/l. Presented in 18 hours after 20 seconds tonic clonic seizure noted by family followed by abnormal flexion. Presented with GCS 7 which then dropped to 5/15 following which patient needed intubation and ventilation. Bloods on admission revealed severe metabolic acidosis with pH 6.90 HCO3 12.4 and lactate 10.2. Sodium 110 mmols/l (normal 135-145 mmols/l) with glucose 12 mmols/l. Given 150mls hypertonic saline which made sodium rise to 119 mmols/l and rapidly normalized in 24 hours. As felt to be acute hyponatremia, advised by endocrinology to avoid further rapid rise with 5% dextrose. Hyponatremia screen included low serum osmolarity 247 (Normal 260-290), random urine sodium was 60, urine osmolarity was 606. This was felt to be similar to an SIADH picture. Lipid profile, TSH were normal. 9AM cortisol and short synacthen test revealed a basal cortisol of 506, 30 minutes cortisol of 881 and 60 minutes cortisol of 1050. Renal function and liver function were normal. MRI Brain/Pituitary was normal. CSF analysis was negative. Therefore, it was opined that seizures were related to medications rather than an intracranial pathology. Patient was gradually stepped down to ward and remained well without fluid restriction. This case highlights the importance of recognising complications associated with medications in chemotherapy day units particularly acute hyponatremia and calls into question whether we need a change in practice and monitoring/admission of these patients post chemotherapy for monitoring.