Case Study: Cushing’s Syndrome

N Kieffer

Leicester Royal Infirmary, UHL NHS Trust

Endocrine Nurses Training Course 10-12 September 2003
St Aidan's College, University of Durham, Windmill Hill, Durham DH1 3LJ

Cushing’s Syndrome occurs when circulating concentrations of corticosteroids are elevated. This can be due to either ACTH dependent or non-ACTH dependent causes. If not iatrogenic, ACTH dependent sources can be from pituitary adenomas or ectopic ACTH producing tumours and non-ACTH dependent sources can be from adrenal adenomas or adrenal carcinomas.

In December 2002 L. was referred to the Endocrine clinic at Leicester Royal Infirmary. The symptoms she reported, an elevated fasting blood glucose (11mmols/l) and a 24hr urinary cortisol of 2276nmols/24hrs prompted the GP to query Cushing’s disease.

L. was seen in clinic in early January 2003. She gave an almost classical history of weight gain, facial hirsutism but thinning of hair on head, spontaneous bruising, muscle weakness and a recent diagnosis of diabetes. She was on no medication, had no significant past history or family history. She was on sick leave from her job as a PA.

Examination showed a ‘buffalo hump’, facial hirsutism, and red striae in abdominal and underarm areas and an elevated blood pressure. She was started on treatment of Gliclazide 40mgs b.d. for her diabetes and several tests and investigations were ordered.

Over the next few weeks L. underwent a low dexamethasone test, a high dexamethasone test and a CRF test. She also had an MRI scan of both her pituitary gland and her adrenal glands.

The MRI scan of the adrenals was normal. Results from the tests suggested an ectopic source but the MRI scan of the pituitary showed a pituitary adenoma. A petrosal sinus catheter was performed on the 17th March 2003 to confirm the source as pituitary and following this L. was started on Metyrapone. The petrosal sinus catheter confirmed that the source was pituitary and L. was referred for transphenoidal surgery but, at her request, it was agreed that this should be deferred until after her planned holiday at the end of July.

Gliclazide was stopped after L. telephoned to report low blood glucose levels and feeling ‘shaky’.

At clinic visit in July L. reported that she felt much better and had returned to work part-time. Cortisol levels were stable on Metyrapone but she reported several elevated blood glucose readings. Gliclazide was restarted on a dose of 40mgs o.d.

Surgery is planned for August 26th 2003 and post-surgery endocrine assessment is planned for 1st September.

The opinions expressed in this paper are those of the speaker and do not necessarily reflect the views of the Society