Diabetes mellitus (pediatrics): Clinical sciences

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Introduction0:00–0:29

Diabetes mellitus, or DM, is a condition characterized by reduced insulin secretion or resistance to insulin, which eventually results in various issues with carbohydrate, protein, and fat metabolism.
Now, there are three main types of diabetes mellitus, including type 1 diabetes mellitus, type 2 diabetes mellitus, and monogenic diabetes, also called maturity-onset diabetes of the young.

Unstable Patient0:29–1:01

Now, if your pediatric patient is presenting with a chief concern suggesting Diabetes Mellitus, first perform an ABCDE assessment to determine if they are unstable or stable.
If unstable, stabilize their airway, breathing, and circulation. Next, obtain IV access, begin IV fluids, and put your patient on continuous vital sign monitoring, including blood pressure, heart rate, and pulse oximetry.
Finally, if needed, provide supplemental oxygen.Once you initiate acute management, obtain a focused history and physical examination, and obtain labs, including serum blood glucose, BMP, serum beta-hydroxybutyrate concentration, urinalysis, and arterial blood gas.

H&P, Labs1:01–1:46

Your patient or their caregiver often reports polyuria, polydipsia, and polyphagia, as well as vomiting, abdominal pain, or confusion.
The physical examination may reveal somnolence often in combination with tachycardia, hypotension, and Kussmaul respirations, which refer to a consistently rapid, deep pattern of breathing.
Other important findings include fruity breath and dry mucous membranes! At this point, suspect Diabetic Ketoacidosis or DKA and assess the criteria for biochemical diagnosis.

DKA criteria1:46–2:16

These include a blood glucose level greater than 200 milligrams per deciliter; arterial pH less than 7.3 OR serum bicarbonate level less than 15 milliequivalents per liter; a beta-hydroxybutyrate concentration of 3 millimoles per liter or higher, and moderate to severe ketonuria.
If your patient meets the criteria, diagnose DKA. Now, keep in mind that up to 25% of children with new-onset DM first present with DKA, and many report a precipitating event, such as an infection or acute illness.

DKA2:16–3:59

However, DKA can also occur in patients with previously diagnosed DM as a result of disrupted insulin treatment. Once you diagnose DKA, begin IV fluid resuscitation to correct dehydration and hyperosmolality, and start an IV insulin drip.
Additionally, begin electrolyte repletion, and monitor sodium and potassium levels. However, be cautious because aggressive correction of hyperglycemia can lead to rapid fluctuations in serum osmolality, resulting in cerebral edema and subsequent complications, like seizures.
If you suspect cerebral edema, give intravenous mannitol. Finally, don’t forget to treat any underlying cause!
Now, here’s a clinical pearl to keep in mind! Another important complication of diabetes mellitus is hyperosmolar hyperglycemic syndrome.
If labs reveal glucose levels above 600 mg/dL; pH above 7.3; bicarbonate levels greater than 18 with variable anion gap; serum osmolality above 320 mOsm/kg; with minimal to none serum and urine ketones, diagnose hyperosmolar hyperglycemic syndrome.
Keep in mind that this condition is typically seen in older patients with type 2 diabetes mellitus!Okay, now let’s go back to the ABCDE assessment and take a look at stable patients.

Stable Patients3:59–4:44

First, obtain a focused history and physical exam. Patients or their caregivers typically report 3 P’s, which include polydipsia, polyphagia, and polyuria.
Moreover, previously toilet-trained children may even develop secondary enuresis. Some patients might report weight loss as well as a family history of DM or other autoimmune conditions, such as thyroid or celiac disease.
Physical exam findings are often unremarkable but may include oral or perineal thrush as well as dry mucous membranes. At this point, suspect diabetes mellitus, so order labs, including hemoglobin A1c, fasting and random blood glucose, and consider obtaining an oral glucose tolerance test.

Suspect DM4:44–5:36

Next, assess findings using the diagnostic criteria for diabetes mellitus. These include hemoglobin A1C of 6.5 percent or greater; fasting blood glucose of 126 milligrams per deciliter or greater; a random blood glucose 200 milligrams per deciliter or greater; or a blood glucose during a 2-hour OGTT that is 200 milligrams per deciliter or greater.
However, remember, these criteria are only useful if your patient is presenting with symptoms of DM. If asymptomatic, you might need to repeat testing to confirm diabetes.
Now, if your patient meets the criteria, diagnose Diabetes Mellitus, and order additional labs to identify the type. Start by obtaining C-peptide levels and islet cell autoantibodies, such as glutamic acid decarboxylase, or GAD65.Now, here’s a clinical pearl to keep in mind!

DM5:36–6:18

C-peptide is a portion of the proinsulin molecule that’s removed during insulin production. Even though C-peptide and insulin are secreted into the blood in similar amounts, insulin is metabolized more rapidly, so C-peptide levels provide a better estimate of insulin secretion.If C-peptide levels are low and any islet cell autoantibodies are positive, diagnose type 1 diabetes mellitus.

T1DM6:18–8:52

In this type, autoimmune destruction of pancreatic islet beta cells results in severe insulin deficiency and subsequent hyperglycemia.
Next, begin insulin therapy.Start with 0.5 to 1 unit per kilogram per day, with half of the total daily dose given as long-acting basal insulin, and the other half given as bolus doses of rapid-acting insulin for meals and snacks.
Bolus dosing is based on the insulin-to-carbohydrate ratio, where one unit of rapid-acting insulin usually covers up to 15 grams of carbohydrates.
Additionally, bolus dosing can be based on blood sugar correction, where one unit of rapid-acting insulin usually drops the blood sugar levels by around 50 milligrams per deciliter.
But, keep in mind that the response depends on many factors, including puberty and the patient's insulin sensitivity. Similarly, blood glucose targets will depend on several factors, including the patient’s age, activity level, and the level of supervision required.Next, provide diabetes management education and support, including how to administer insulin, how to monitor and interpret blood glucose levels, and how to manage hypo- and hyperglycemia.
Your patient should also work with a dietician to learn how to count carbs, determine pre-meal insulin dosing, and adjust insulin dosing for changes in routine, like illness and increased physical activity.
Now, keep in mind that type 1 diabetes is often associated with other autoimmune conditions, like celiac disease and hypothyroidism, so be sure to screen for these conditions too!
Finally, follow your patient’s response to treatment to ensure adequate glycemic control, which helps prevent long-term complications, like diabetic retinopathy, neuropathy, and nephropathy.
Many children also benefit from a psychosocial assessment for support as they adjust to a new lifestyle.Here’s a clinical pearl to keep in mind!
Patients who require frequent glucose testing might require a continuous glucose monitor. Similarly, an insulin pump is a wearable device that provides a continuous insulin infusion, and some glucose monitors and insulin pumps can communicate in real time.

Non-immune-mediated DM8:52–9:29

Alright, let’s switch gears and consider patients with normal or elevated C-peptide levels and negative pancreatic islet antibodies.
In this case, diagnose non-immune-mediated diabetes mellitus, and assess your patient’s characteristics. If your patient is less than 25 years old and has a history of neonatal diabetes or a multigenerational family history of DM, with an affected parent, suspect maturity-onset diabetes of the young, or MODY.
In this case, your first step is to obtain genetic testing.If you identify a single gene mutation, such as GCK or HNF, diagnose MODY, which is an autosomal dominant condition associated with impaired insulin release.

MODY9:29–10:12

Disease severity depends on the specific mutation, but most patients don’t require insulin. Unlike type 2 diabetes, MODY isn’t associated with insulin resistance or progressive loss of insulin secretion.
Once you diagnose it, provide education and encourage lifestyle and dietary modifications. Finally, if needed, start your patient on oral sulfonylureas to stimulate insulin secretion, and be sure to offer genetic counseling.
However, if the genetic testing reveals no mutations, your patient likely has type 2 diabetes mellitus.Now, let’s go back to your patient’s characteristics one more time!

T2DM10:12–11:13

If your patient has a family history of type 2 diabetes, and the physical exam reveals elevated BMI, hypertension, and acanthosis nigricans, you can diagnose type 2 diabetes without genetic testing.
This condition is characterized by insulin resistance and progressive loss of pancreatic insulin secretion. Most commonly, it co-occurs with metabolic syndrome, which consists of abdominal obesity, insulin resistance, dyslipidemia, and hypertension.
Management primarily relies on education about blood glucose monitoring and lifestyle changes, like exercise and healthy eating.
Many patients will also require oral hypoglycemic medications, such as metformin, and some may require insulin.Alright, as a quick recap… If you suspect diabetes mellitus and your patient meets the criteria for DKA, begin IV fluid resuscitation, intravenous insulin, and electrolyte repletion and monitoring.

Review11:13–11:52

On the flip side, if your patient is stable and meets the criteria for diabetes mellitus, obtain C-peptide levels and islet cell autoantibodies.
Low C-peptide levels and positive autoantibodies are diagnostic for type 1 diabetes. However, normal or elevated C-peptide levels and negative antibodies indicate non-immune-mediated Diabetes Mellitus, such as MODY and type
Diabetes mellitus (pediatrics): Video and Causes | Osmosis