Chapter 28: Endocrine Dysfunction in Children

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Welcome back to The Deep Dive.

Today we are tackling a system of the body that I think a lot of us find a little mysterious.

It's invisible, it's all chemical, but when it goes wrong, the effects are, well, they're absolutely everywhere.

They are.

We're talking about the endocrine system.

They are.

And specifically, we are diving into Chapter 28 of Wong's Essentials of Pediatric Nursing, looking at the child with endocrine dysfunction.

And this isn't just, you know, a biology refresher.

We are really looking at this through the lens of pediatric nursing.

We have a very specific mission today.

We do.

We want to translate these really complex hormonal pathways, which can feel like a ton of abstract chemistry,

into safe, effective practice.

So we're talking about things like growth, metabolism, and sexual maturation.

Exactly.

And the reason this matters so much for nurses, I mean, really for anyone caring for kids, is that endocrine disorders, they just rarely show up with a flashing neon sign.

Right.

They masquerade, they look like behavioral changes, or a child who's just always tired, or a kid who suddenly starts wetting the bed again.

So it's detective work.

You have to look past the surface symptoms to find the chemical culprit.

It is, 100%.

Nurses are often the frontline for spotting these really subtle cues.

And catching them early is the difference between, you know, a minor course correction and a life -altering complication like brain damage, or even diabetic ketoacidosis.

Okay.

So let's set the stage before we get into the specific diseases.

What is the endocrine system, really, in the simplest terms?

Think of it as a thermostat.

That's the classic analogy for what we call the negative feedback loop.

So the whole system controls metabolism, energy, growth, fluid balance.

It does all this using chemical messengers called hormones.

And just like a thermostat, detects when the room is too cold and turns on the heat.

The gland turns on.

Right.

The endocrine glands detect low hormone levels and they turn on production.

When the levels get high enough, the thermostat clicks off and production stops.

And when that thermostat breaks, you refreeze or you roast.

Precisely.

And in the body, that means either hypofunction,

so too little hormone, or hyperfunction, way too much.

Okay.

Let's start at the top.

The boss,

the master gland,

the pituitary.

The pituitary gland.

It's this tiny pea -sized structure at the base of the brain, but it absolutely runs the show.

And it's divided into two lobes, the anterior and the posterior.

And they do very different things.

Very different.

We need to treat them almost like separate organs when we think about what can go wrong.

Okay.

So let's start with the anterior pituitary.

This is the part that's responsible for growth, right?

So what happens when the master gland isn't doing its job here?

Well, a major issue we see is hypotuitarism and specifically growth hormone deficiency.

This is when the pituitary just isn't putting out enough of that hormone, somatotropin or GH.

And I'm guessing the main symptom is

they don't grow.

They don't.

But the pattern is really specific and this is so important for the assessment.

Usually these babies, they grow normally for the first year.

So everything seems fine at first.

Everything seems fine.

But then the curve just flattens.

They start tracking below the third percentile on the growth chart.

So it's a drop off.

It's not that they were always small.

It's that they stopped keeping up with their peers.

Correct.

And because GH also affects muscle mass and metabolism, these kids might look sort of obese, even though they aren't overeating.

Oh, that's interesting.

Yeah.

They have stunted height, but good nutrition.

They often have these very youthful cherubic facial features.

So they look younger than they actually are.

How do we diagnose that?

Is it just a blood test to check the hormone levels?

Blood tests are part of it for sure.

But a really crucial tool is the hand -wrist x -ray.

An x -ray.

What are you looking for?

We're looking for bone age.

We look at the ossification centers in the bones.

And if the bone age is delayed, meaning the bones look, you know, younger than the child's chronological age, that's actually good news in a way.

Why is that good news?

I would think any kind of delayed development is bad.

It's good news because it means the growth plates or the epiphysis, they haven't closed yet.

Ah, so there's still time.

There is still potential for growth if we treat it.

If the bone age matched the chronological age in a short child, it might mean their growth is already done.

But a delay means the window is still open.

And the treatment is just more hormone.

Biosynthetic growth hormone injections.

And this is where the nursing education part is just huge.

Maly shots.

I imagine that's a lot for a family to manage.

It is a ton.

And the nurse has to teach the family how to do it.

But here's a specific tip that comes straight from the physiology.

Okay.

You have to administer the injection at bedtime.

So we're asking parents to give a daily injection.

That's already a huge ask.

And you're saying the source material highlights a very specific constraint on when to give it.

Bedtime is non -negotiable.

Is that just for convenience?

No, not at all.

It's pure biology.

This is one of those cool moments where nursing practice has to perfectly mirror physiology.

You have to understand that the pituitary is, well, it's a creature of the night.

A creature of the night.

I like that.

Exactly.

Natural growth hormone isn't released in a steady stream, like a leaky faucet.

It's pulsatile.

It comes in bursts.

And the biggest, most important surge happens specifically during deep sleep.

Usually about 45 to 90 minutes after the child drifts off.

So if we give the synthetic hormone at eight in the morning.

You're fighting the body's natural rhythm.

By giving it right before sleep, we are trying to perfectly simulate that natural nocturnal spike.

You're tricking the body.

You're tricking the body into thinking it's doing the work itself.

It's all about optimizing uptake.

If you give in the morning, you're essentially wasting a portion of that very expensive, very vital medication because the body just isn't primed to receive it.

That makes total sense.

Okay.

Now, what if the thermostat gets stuck in the on position?

Too much growth hormone.

Right.

That leads to pituitary hyperfunction.

And the outcome depends entirely on when it happens.

When in their development.

If you have excess GH before those growth plates close, you get gigantism.

The child grows incredibly tall, sometimes eight feet or even more.

And if it happens after the plates are already closed.

Then the bones can't grow longer, so they just grow thicker.

That's acromegaly.

So like sideways growth.

You see transverse growth.

A thick face, a heavy jaw, very large hands and feet.

For nurses, if you see a child with this kind of rapid growth, you need to watch for headaches.

Headaches.

Why headaches?

Yeah.

Remember, this is often caused by a tumor on the pituitary.

That tumor takes up space in the skull, right?

It causes pressure.

You also need to watch for signs of diabetes because growth hormone actually opposes insulin.

Too much GH can shoot your blood sugar way up.

Okay.

Let's move to another issue involving the anterior pituitary.

Precocious puberty.

This is when the alarm clock rings way, way too early.

Way too early.

We're talking about sexual development before age nine in boys or age eight in girls.

Sometimes even younger, depending on ethnicity.

It's just confusing for the child and absolutely terrifying for the parents.

I can only imagine.

What causes it?

Well, in what we call central precocious puberty or CPP, the hypothalamus essentially just wakes up too early.

Interestingly, in about half of the cases, it might actually regress on its own without treatment.

Really?

Yeah.

But if it doesn't, we have to treat it because those hormones will ripen the bones way too fast.

The growth plates will close early and the child will end up being a very short adult.

So we have to hit the pause button on puberty.

Exactly.

We use a drug called Lupralide or Lupron Depot.

It slows everything down to preserve their final adult height potential.

But there's a huge psychosocial piece here for the nurse.

I was just going to ask about that.

I mean, you have a six -year -old who might look like a 12 -year -old.

Right.

And people tend to treat them like they're 12.

The nurse has to constantly remind everyone, parents, teachers, family, to dress and treat the child according to their chronological age.

Their body has changed, but their mind is still six.

Precisely.

And their sexual interests, that's another thing parents worry about.

It's usually appropriate for a six -year -old, not what their body might suggest.

It's a really important distinction to make.

That is such an important distinction.

Okay, let's shift lobes.

The posterior pituitary.

This is all about fluid balance, isn't it?

It is.

The key player here is ADH antidiuretic hormone.

I like to call it the don't pee hormone.

The don't pee hormone.

I can remember that.

It tells the kidneys to hold onto water.

So if you don't have enough of the don't pee hormone.

You get diabetes insipidus or DI.

We remember this with the phrase high and dry.

High and dry.

Okay, unpack that for me.

High sodium in the blood because they're losing all their water and dry because they are profoundly dehydrated.

The cardinal signs are polyuria, that's excessive peeing, and polydipsia insatiable thirst.

And this is what you mentioned bedwetting earlier.

That's a classic sign.

Yes, this is a classic red flag.

If you have a seven -year -old who has been toilet trained for years and suddenly starts wetting the bed or needs to drink water constantly, you have to think about DI.

What about in babies?

In an infant, they might just be incredibly irritable and you know, milk doesn't soothe them.

They stop crying only if you give them water.

Wow, how do we confirm it?

With a water deprivation test.

We restrict fluids and see what happens.

In a healthy kid, their urine would get concentrated and dark because the body is saving water.

Right.

In a kid with DI, they just keep peeing, dilute, clear urine even though they're dehydrating.

Their body simply cannot shut off the tap.

And the fix for that?

We replace the hormone with a drug called DDAVP or desmopressin.

It's usually a nasal spray or an injection.

And here is a critical, critical nursing alert for the injectable form.

I'm ready.

If you are using the oil -based suspension, you have to shake it.

You must resuspend it until you can actually see the brown particles floating around.

And if you don't?

If you don't, the oil stays at the top.

The drug sinks to the bottom and you might just inject oil.

The patient gets no medication at all.

That is a life or death detail right there.

Shake the vial.

Okay.

Got it.

Now what's the opposite of DI?

That would be SIADH,

syndrome of inappropriate antidiuretic hormone.

And this one is low and wet.

Too much don't pee hormone.

Exactly.

The body holds onto way too much water.

This dilutes all the sodium in the blood.

So you get hyponatremia, dangerously low sodium.

And why is that so dangerous?

Because low sodium causes water to shift into the brain cells.

You get brain swelling.

So the top nursing priority here is seizure precautions.

Absolutely essential.

And you have to restrict fluid strictly to prevent the brain from swelling any further.

It's a very delicate balancing act.

Okay.

So pituitary, master gland.

Anterior is growth and puberty.

Posterior is fluid balance.

Let's move down the neck to the thyroid.

The thyroid.

This little gland regulates your basal metabolic rate or BMR.

It's basically the engine speed of your body.

And in infants, this is critical for brain growth, right?

Absolutely crucial.

That's why we have mandatory newborn screening for it.

Confederal hypothyroidism is an emergency for the developing brain.

If we miss it in those first few weeks, the intellectual disability is permanent.

But it can also happen in older kids.

Yes.

In older kids, we see what's called juvenile hypothyroidism.

What does that look like?

Think slow.

Everything slows down.

Decelerated growth is often the first sign you'll see.

Then you get dry skin, puffiness around the eyes,

constipation, lethargy, cold intolerance.

The engine is just idling too low.

And the treatment for that is pretty straightforward.

It is, yeah.

Daily oral replacement with levothyroxine.

But it takes a while to work.

It's not an overnight fix, and families need to understand that.

Now, what about a goiter?

I always picture this huge lump on someone's neck.

It is an enlargement of the thyroid gland.

But here's the tricky part.

It can happen if the thyroid is underactive, overactive, or even working perfectly normally.

Really?

Yeah.

It's just the gland trying to compensate for something.

Is it dangerous?

It can be.

A major nursing alert here.

If an infant is born with a goiter, it can press on their trachea.

It is an airway emergency.

Wow.

You might need to hyperextend the baby's neck just to open the airway, and you absolutely have to have a tracheostomy set ready at the bedside just in case.

Yikes.

So what's the most common cause of thyroid disease in kids?

That would be lymphocytic thyroiditis, also known as Hashimoto's disease.

It's an autoimmune condition.

The body basically attacks its own thyroid.

And what would a nurse feel on assessment?

You'll feel an enlarged, firm, non -tender, movable thyroid.

Pretty classic presentation.

And on the flip side, we have hyperthyroidism, Grave's disease.

Right.

Now the engine is racing.

Everything speeds up.

These kids have a voracious appetite.

They're losing weight.

They're heat intolerant, emotionally labile.

Their heart is racing tachycardia.

And you might see exothelmos.

The bulging eyes.

Bulging eyes, yes.

I've heard of something called thyroid storm.

That sounds terrifying.

It is a life -threatening crisis.

Severe tachycardia, high fever, vomiting.

It can be triggered by an infection or if a child just stops their meds abruptly.

So what's the nurse's role there in managing a child with hyperthyroidism?

The environment is key.

These kids are revving so high, you need to limit their activity.

A quiet environment is crucial.

Schoolwork only.

No vigorous exercise in gym class until their levels normalize.

Or you risk serious heart complications.

You have to basically force the engine to idle down.

Okay, right next door to the thyroid are the parathyroids.

These handle calcium, right?

Yes.

Parathyroid hormone, or PTH, it acts like a calcium miner.

It pulls calcium out of the bones and into the blood.

So hyperthyroidism means low PTH, which means low calcium.

Low PTH equals low calcium.

And low calcium makes muscles go absolutely crazy.

We call it tetany.

Muscle cramps, tingling, twitching.

This is where you have those specific signs with the funny names, right?

Schwastek and Trousseau.

Vital for nursing exams and for real life.

Remind us what they are.

The Schwasti sign is a facial twitching when you tap the facial nerve on the cheek.

And the Trousseau sign is a carpal spasm.

The hand curls in on itself when you pump up a blood pressure cuff on the arm.

And if you see those signs?

Seize your precautions immediately.

And you need to have IV calcium gluconate ready to go.

But be really careful of that IV if it leaks into the tissue, if it extravasates, it causes necrosis, it eats the skin.

Noted.

Calcium is serious business.

Okay, let's move down to the kidneys.

Or, well, on top of them, the adrenal glands.

The adrenal cortex.

It produces three types of steroids.

Glucocorticoids, which is sugar.

Mineral corticoids, which is salt.

And sex steroids.

Sugar, salt, and sex.

I can remember that.

It's a good mnemonic.

Let's talk about when the adrenals fail.

Adrenal crisis.

Acute adrenocortical insufficiency.

This is a true medical emergency.

It can happen from trauma, an overwhelming infection like meningocosemia, or, and this is a common one, from stopping steroid meds abruptly.

What does it look like?

It looks like shock.

Hypotension.

A weak, thready pulse, cold, clammy skin.

Their blood pressure just bottoms out because they don't have the cortisol to maintain their vascular tone.

And the fix.

Fluids and cortisol.

Immediately.

You give IV fluids to bring up the blood pressure and you give solucortef, which is hydrocortisone, to replace the hormone.

Now, what about the chronic version of that?

Addison disease.

Chronic insufficiency.

These kids often have hyperpigmentation.

They look bronze or really tanned, especially in their skin creases.

They crave salt and they're just generally weak.

There is a stress rule for these families, isn't there?

There is, and it is absolutely non -negotiable.

Because their body cannot mount a natural stress response, if the child gets sick, has a fever, or needs surgery, the parents must triple the cortisol dosage.

Triple the dose.

If they don't, the child can go into shock and die.

It's that serious.

Got it.

Now, what if you have the opposite problem?

Too much cortisol.

Cushing syndrome.

Cushings.

In children, this is usually iatrogenic, meaning we caused it by giving high -dose steroids for something else, like asthma or an autoimmune disease.

What are the telltale signs?

The classic moon face, a very round face, the buffalo hump of fat on the back of the neck, red stretch marks we call striae, and poor wound healing.

And I assume we just stop the steroids.

No.

Never, ever stop abruptly.

That will trigger in a genal crisis.

You have to taper gradually.

And a good tip is to try to give the steroids in the morning to mimic the body's natural diurnal rhythm.

I want to slow down on congenital adrenal hyperplasia, or CAH.

The text mentions 21 hydroxylase deficiency.

That sounds like the kind of phrase that makes nursing students' eyes glaze over.

It does.

Can we unpack what is actually breaking down here?

Let's do it.

Let's visualize the adrenal gland as a factory.

This factory has three assembly lines running side by side.

Line one makes aldosterone for salt balance.

Line two makes cortisol for stress and sugar.

And line three makes androgens or sex hormones.

Salt, sugar, and sex.

The three S's again.

Right.

Now, to make cortisol in line two, you need a specific worker and enzyme called 21 hydroxylase.

In CAH, that worker's missing.

He just didn't show up for his shift.

Though line two completely stops.

Line two halts.

The body stops making cortisol.

But here's the kicker.

The brain doesn't know the worker is missing.

The brain just sees low cortisol levels and starts screaming at the factory, make more, make more.

It pumps out ACTH to stimulate the whole factory.

But the factory literally can't make cortisol.

It can't.

But because the factory is being stimulated so aggressively, it dumps all its raw materials onto the only line that is working, which is line three, the androgen line.

Oh, I see.

So it's not just that they don't have cortisol.

It's that all the resources are being diverted to testosterone production.

Bingo.

You get a massive overflow of male hormones.

That's why a female infant with CAH is born with ambiguous genitalia.

Her body has been flooded with androgens and utero.

And what about the salt part?

Well, line one often shares that same missing worker.

So you have no salt regulation either.

You have a baby who is masculinized on the outside, but internally they are on the verge of a salt wasting crisis that can stop their heart.

So for the nurse, seeing ambiguous genitalia isn't just a cosmetic issue.

It requires urgent medical evaluation.

Absolutely.

And supporting the parents through the shock and the eventual gender assignment discussions is a huge part of the care.

I mean, this is a profound crisis for a family expecting a boy or a girl and being told, we aren't sure.

One last adrenal issue, pheochromocytoma.

Try saying that three times fast.

Well, I'll just stick to pheo.

It's a tumor on the adrenal medulla that secretes catecholamines epinephrine.

So a constant adrenaline overdose.

Yes.

You see hypertension, a racing heart, sweating, a bad headache.

But here is the massive nursing alert for this one.

Okay.

Do not palpate the abdomen.

Why not?

Nurses palpate abdomens all the time.

If you push on that tumor, you can squeeze out a massive burst of epinephrine.

You can cause a severe hypertensive crisis right there on the exam table.

If you even suspect a pheo, keep your hands off the belly.

Hands off.

Understood.

We've arrived at the big one.

The most common metabolic disease in children.

Disorders of the pancreas.

Diabetes mellitus.

This is a huge topic.

In pediatrics, we are mostly dealing with type 1, though unfortunately type 2 is increasing due to the obesity epidemic.

What's the fundamental difference?

Type 1 is an immune mediated destruction of the beta cells.

The body kills its own insulin factory.

It's an absolute insulin deficiency.

Type 2 is resistance.

The insulin is there, but the locks on the cells are rusty and don't work well.

Let's focus on type 1 for a minute.

The pathophysiology is essentially starvation in the midst of plenty, right?

That's a great way to put it.

The blood is full of sugar or glucose, but it can't get into the cells without insulin.

So the cells are literally starving.

And that leads to the classic symptoms, the three P's.

The three P's, polyuria, polydipsia, and polyphagia.

Okay, break them down for us.

Polyuria.

The blood sugar gets so high it spills into the urine.

And sugar pulls water with it.

That's osmotic diuresis, so the kid pees constantly.

Polydipsia.

Right.

Because they are peeing so much, they become dehydrated and incredibly thirsty.

And polyphagia.

The cells are starving, so they send constant hunger signals to the brain, even though the blood sugar is sky high.

And if we don't catch it at this stage?

The body switches to plan B, burning fat and protein for fuel.

The byproduct of burning fat is ketones, and ketones are acidic.

This leads directly to decay diabetic ketoacidosis.

Let's talk about the nightmare scenario.

DKA.

A child comes into the ER.

They are breathing like a freight train.

Cousmal respirations.

Their breath smells like rotting fruit.

And their blood sugar is, say, 600.

It's a terrifying presentation.

Now, my instinct, and I think the instinct of any compassionate person, is to look at that blood sugar of 600 and say, we need to bring that down now.

I want to grab the insulin.

And if you do that, you might kill the patient.

That is a very counterintuitive statement.

The problem is high sugar.

Why is giving insulin the dangerous part?

Because you have to look at what else is happening in the blood.

When a child is in DKA, they are profoundly dehydrated.

Their whole vascular system is shrunken.

If you slam them with insulin right away, you drive glucose into the cells and water follows it.

You can cause massive fluid shifts that lead directly to cerebral edema.

You swell the brain.

You swell the brain.

And by trying to fix the sugar too fast, you crush the brain stem.

Wow.

But there is a second trap.

Potassium?

The heart.

The heart.

Insulin doesn't just open the door for sugar.

It acts like a shepherd for potassium, driving it back inside the cells.

These kids often have depleted total body potassium, even if their blood labs look normal at first.

If you start an insulin drip before you've verified they have enough potassium on board, you will bottom them out.

You will send them into cardiac arrest.

So the fluid's first rule isn't just about hydration.

It's about buying time to make sure you don't stop the heart while you're trying to fix the sugar.

Exactly.

We restore perfusion with isotonic saline first.

We check the T waves on the cardiac monitor.

Only when we know the tank is full and the heart is safe do we even touch the insulin.

Slow and steady wins the race in DKA.

Once they are out of the woods, it's about management.

Lifelong insulin therapy.

It's a lifelong balancing act.

We have rapid acting insulins like Novolog, short acting like Regular, intermediate like NPH, and long acting like Lantus.

It's a whole new language for families.

It seems like insulin pumps are becoming more and more common.

They are.

Pumps mimic the pancreas better by giving a continuous basal rate and then bolus doses for meals.

But they require a lot of commitment.

You have to do the math.

You have to count carbs.

You have to change the site every few days.

It's a lot of work.

And what about the goal?

What are we aiming for with blood sugar control?

We look at the hemoglobin A1C.

This test tells us the average blood sugar over the last two to three months.

For most kids, we want it to be below 7 .5 percent.

Let's talk about the scary moments at home.

Hypoglycemia versus hyperglycemia.

How do parents tell the difference quickly?

Hypoglycemia is so.

Low sugar hits fast.

The child gets irritable, shaky, sweaty.

We have a saying, cold and clammy, need some candy.

And the treatment?

10 to 15 grams of a simple carb, half a cup of juice or milk or glucose tabs.

If they pass out, the family needs to know how to give a glucagon injection.

And hyperglycemia.

High sugar.

That's more gradual.

They get lethargic, thirsty, their skin is dry, hot and dry, sugar high.

There is one rule about sick days that you highlighted in the notes, and it seems really important.

The crucial rule.

Never ever omit insulin during illness.

Even if the child isn't eating.

Why not?

Illness releases stress hormones, cortisol and epinephrine, that naturally raise blood sugar.

Parents often think, he's vomiting, he's not eating, I shouldn't give insulin.

That is how they end up back in the hospital in DKA.

They need to monitor for ketones and keep giving insulin, even if they have to adjust the dose.

We've covered a massive amount of ground from the pituitary all the way down to the pancreas.

If you had to boil this all down for the listener, what are the big takeaways?

I'd say first, growth is a vital sign.

If a child stops growing or grows way too fast, you have to think endocrine.

Second, safety is paramount.

We're talking about airway and a goiter.

Seize your precautions if sodium or calcium is low.

And careful cardiac monitoring in DKA.

These are the things that can kill a patient quickly.

And the third?

And finally, education is the treatment.

Most of these are chronic lifelong conditions.

The medicine isn't just the pill or the shot.

It's the family knowing how and why to give it every single day.

The nurse is really the bridge between the complex science and the family's daily life.

Exactly.

The endocrine system is a communication network.

When it breaks, the message gets lost.

And our job as nurses is to help reconnect those lines so the child can just be a child.

I love that, reconnecting the lines.

Well, that is a wrap on our deep dive into the pediatric endocrine system.

It's complex, it's chemical, but hopefully it's a little less mysterious now.

Always a pleasure.

This has been the Last Minute Lecture Team.

Thanks for listening.

And go ace that exam or that shift.

We'll see you in the next deep dive.