Tanning in Addison's disease

Q: During a clinical exam for adrenal insufficiency, which 2 sites can easily be examined for the characteristic 'tanning'?

Answer: 

• skin creases (mostly palm) 
• buccal mucosa

Addison's disease (adrenal insufficiency) causes patchy and sometimes uniform skin tanning all over the body. Two characteristic sites of tanning to look for are skin creases (as of the palms) and the inside of the cheek (buccal mucosa). 

This tanning occurs due to increased production of melanocyte-stimulating hormone (MSH) and adrenocorticotropic hormone (ACTH) when the adrenal glands fail and cortisol production decreases. MSH stimulates melanocytes to produce more pigment, especially in areas that are mostly exposed to sunlight and pressure, such as the knuckles, knees, and armpits. The slang used for such tanning is either "bronzing or bronze man." It gives the patients a very peculiar look compared to the individuals around.

#endocrinology

#physical-exam

References:

1. Tong CV, Ooi XY. Addison's disease presenting with hyperpigmentation. BMJ Case Rep. 2021 Aug 17;14(8):e245610. doi: 10.1136/bcr-2021-245610. PMID: 34404673; PMCID: PMC8375727.

2. Munir S, Quintanilla Rodriguez BS, Waseem M. Addison Disease. 2024 Jan 30. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan–. PMID: 28723023.