A 51-year-old Afro-Caribbean lady with a history of primary hyperparathyroidism, type 2 diabetes and hypertension was admitted with confusion. Her medication at the time included five anti-hypertensives.
She was treated for an infection but despite a long course of antibiotics she remained confused with visual hallucinations and aggression.
She was noted to have resistant hypertension with systolic blood pressures over 220 mmHg and persistent hypokalaemia, this prompted assessment for endocrine causes. On examination there was no evidence of cushingoid features. Low dose dexamethasone suppression tests revealed morning cortisols between 500 and 600 nmol/l however due to suspected non-concordance from the psychosis a repeat suppression test with 2 mg i.v. dexamethasone was administered. This also showed failure to suppress with a morning cortisol of 875 nmol/l and ACTH of 149 ng/l.
Baseline cortisol was 972 nmol/l and ACTH was 250.9 ng/l; following a high dose dexamethasone suppression test, cortisol was 885 nmol/l with ACTH 247 ng/l confirming ACTH dependant Cushings syndrome.
MRI with contrast showed no evidence of pituitary adenoma and a CT scan revealed a 3.3 cm right lung nodule with bilateral adrenal hyperplasia compared to previous scans.
Her psychosis worsened despite antipsychotic medication therefore etomidate 3 mg/kg was administered in an ITU setting but was ineffective. Subsequently ketoconazole 600 mg TDS was tried with no improvement and random plasma cortisols remained over 1000 nmol/l.
She underwent a resection of the nodule which stained positive for TTF-1, synaptophysin, CD56 and chromogranin, in keeping with carcinoid. The patients psychosis, blood pressure and glycaemia improved with cortisol levels settling to 100 nmol/l.
This complex case highlights the unusual presentation of Cushings syndrome from an ACTH secreting carcinoid lung tumour. It highlights the extreme and resistant psychosis that can accompany such patients, not previously described in literature. Acute psychosis in a young patient with resistant hypertension, diabetes and hypokalaemia should lead to suspicion of hypercortisolaemia.