Endocrine Abstracts

A 67-year-old lady was admitted through her General Practitioner with a history of reduced oral intake & unresponsiveness. She was diagnosed to have an insulinoma in 2012 and has been on diazoxide 75 mg thrice daily as she was deemed to be unfit for any surgical intervention. On clinical examination, she was pyrexial, tachycardic, hypoxic and had an initial GCS of 3. She was noted to have shingles on her chest & right basal coarse crackles.

On admission her blood glucose was surprisingly found to be elevated at 44 mmol/L considering her past diagnosis of an insulinoma. She was clinically dry with a sodium of 162 mmol/L, Urea of 32 mmol/L, Creatinine of 162 umol/L and a Serum osmolality of 408 mmol/kg. She had a positive varicella zoster (VZ) PCR and a CTPA confirmed a right lower lobe consolidation. Her HbA1c was 39 mmol/mol.

The above clinical & investigation findings supported a diagnosis of Hyperosmolar hyperglycemia state (HHS) triggered by pneumonia & VZ infection. She was given IV fluids, IV antibiotics, variable rate IV insulin infusion & IV acyclovir. Her Diazoxide was stopped on admission.

Diazoxide was believed to be a potential agent precipitating HHS in our patient through its inhibitory effect on pancreatic insulin release & subsequent uninhibited glycogenolysis. In our patient, the effect was likely to have been amplified by sepsis triggering adrenocortical and catecholamine release potentiating further glycogenolysis. She recovered well in the next 48 hours and was discharged home. Unfortunately she was re-admitted again few days later and died in hospital due to bronchopneumonia.

To our knowledge this is a first case report of this kind where HHS has developed as a complication of diazoxide therapy for insulinoma. This case warns the possibilities and dangers of diazoxide therapy and highlights the importance of monitoring blood glucose & ketones particularly during intercurrent illnesses.