Hi, this is Tom, and in this episode I'm going to be going through adrenal insufficiency in children.

And you can find notes at zero to finals.com and in the zero to finals pediatrics book.

And you can find flashcards and questions at members.0.0.5.com.

And at the end of the episode, we'll go through some questions to test you on what you've just heard.

So let's jump straight in.

Adrenal insufficiency is where the adrenal glands do not produce enough steroid hormones, particularly cortisol and

aldosterone. Steroids are essential for life, making the condition life-threatening.

Let's start by talking about glucocorticoids and mineralocorticoids. The adrenalocytes produce two types of steroid hormones.

Cortisol, which is a glucocorticoid, and aldosterone, which is a mineralocorticoid.

Glucocorticoids, like cortisol, help the body to cope with stress.

Cortisol has several actions in the body.

It increases alertness, inhibits the immune system and reduces inflammation,

inhibits bone formation, raises blood glucose levels, increases metabolism and supports

cardiovascular function like heart rate, blood pressure and the cardiac output. Mineralocorticoids

like aldosterone help regulate the balance of electrolytes and the blood pressure.

They act on the nephrons in the kidneys to increase sodium reabsorption from the distal tubule,

increase potassium secretion from the distal tubule,

and increase hydrogen secretion from the distal tubule and increase hydrogen secretion from the collecting ducks.

The key things to remember are that aldosterone causes more sodium to be reabsorbed and retained

in the body and more potassium to be secreted in the urine.

Let's go through the adrenal axis.

The hypothalamus releases corticotropin releasing hormone, or CRH,

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