Matching Clinical Signs to Differential Diagnoses: PACES Cheatsheet (Endocrinology)

Matching Clinical Signs to Differential Diagnoses: PACES Cheatsheet (Endocrinology)

I did cheat sheets for all the possible constellation of signs I could think that may come up during a PACES exam. I mentioned in my PACES Exam Guide Series (Part 1) that best advise I received at the time I was revising was that “You don’t have time to think during the exam, So have your differentials ready at the tip of your tongue.” So I invested a fair bit of time doing pattern recognition – if “these” signs turn up the differentials are likely to be “this list”. And have this ready. So when you get a unilateral pure motor neurone patterns of weakness in the real deal, you have in impressive list ready to blurt out to the examiner. You sound more organised, systematic, confident if you have this but of knowledge under your belt so you focus your energy in PACES on how you come across rather than remembering what diagnoses can be at play here. And it worked – I attribute so much of my PACES Success where I scored 168/172 on the first attempt to this. So, thank you Registrar! 

Causes of Adrenal Failure/ Hypoadrenalism:

Primary Adrenal Failure

  • Autoimmune (commonest- Addisons disease)
  • TB (common worldwide)
  • Infiltrative causes: Malignant infiltration, Sarcoidosis, Haemachromatosis, amyloidosis
  • Waterhouse Frederickson Syndrome
  • Thrombotic disease

Secondary Adrenal Failure 

  • Iatrogenic (due to exogenous steroid administration)
  • Anterior pituitary failure due to tumour, stroke, apoplexy

Causes of hypercortisolism:

Cushing’s: 

  • Exogenous steroids
  • ACTH independent causes: adrenal adenoma, adrenal hyperplasia
  • ACTH dependent: Ectopic ACTH production, Pituitary adenoma

Pseudo-Cushings: related to Depression/alcoholism

Causes of hyperthyroidism:

  • Commonest: Graves (look for Grave’s Eye signs + history of autoimmune disease) and Toxic multinodular goitre
  • Thyroiditis: Neck Pain (subacute); recent child birth (postpartum); autoimmune (“Silent”)
  • Gestational Thyrotoxicosis
  • Drug Induced: contrast medium, amiodarone, lithium
  • Other causes: factitious thyroxine use

Causes of hypothyroidism:

  • Commonest: Autoimmune or Hashimoto’s thyroiditis
  • Post-treatment: thyroid ablation, radioiodine or surgery
  • Thyroiditis: Follow the transient hyperthyroid state
  • Drug-Induced: amiodarone, lithium, anti-thyroid medications

What are the complications of acromegaly?

  • Cardiovascular: Cardiomyopathy, diabetes, hypertension
  • Respiratory: Obstructive sleep apnoea
  • Gastrointestinal: Colonic cancer/Polyps
  • Renal: Hypercalciuria
  • Bones: OA