# Clinical Cases: Pediatric Endocrine Disorders

## Case 1: Diabetic Ketoacidosis - New Onset Type 1 Diabetes

### Patient Demographics
- **Age:** 10-year-old female
- **Sex:** Female

### Chief Complaint
"She's been drinking a lot of water, urinating frequently, and now she's vomiting and seems confused."

### History of Present Illness
A 10-year-old previously healthy female presents with 3 weeks of progressive polyuria, polydipsia, and a 4 kg weight loss despite increased appetite. Over the past 2 days, she has developed nausea, vomiting, and abdominal pain. Today, she became increasingly lethargic and her breathing has become deep and rapid. Her parents initially thought she had a stomach virus. There is no prior history of diabetes, but her maternal grandmother has type 2 diabetes. She has had no recent illnesses or medication use.

### Physical Examination
- **General:** Ill-appearing, lethargic but arousable, deep rapid breathing (Kussmaul respirations)
- **Vital signs:** Temp 36.5°C, HR 130 bpm, RR 32/min (deep), BP 95/60 mmHg, Weight 28 kg (down from 32 kg 3 weeks ago)
- **HEENT:** Dry mucous membranes, sunken eyes, fruity odor on breath
- **Cardiovascular:** Tachycardic, regular rhythm, no murmur
- **Respiratory:** Clear, deep breathing
- **Abdomen:** Soft, diffusely tender, no guarding or rebound
- **Skin:** Dry, poor turgor (tenting)
- **Neurologic:** Lethargic, oriented to person only, moves all extremities

### Workup
- **Point-of-care glucose:** 485 mg/dL
- **BMP:** Na 131 mEq/L (corrected Na 138), K 5.4 mEq/L, Cl 98 mEq/L, HCO3 8 mEq/L, BUN 28 mg/dL, Cr 1.1 mg/dL, Glucose 478 mg/dL
- **Anion gap:** 25 (elevated)
- **VBG:** pH 7.12, pCO2 18 mmHg
- **Serum ketones:** Strongly positive (beta-hydroxybutyrate 6.8 mmol/L)
- **Urinalysis:** Glucose 3+, ketones 3+
- **HbA1c:** 12.8%

### Diagnosis
**Diabetic ketoacidosis (severe) as initial presentation of Type 1 diabetes mellitus**

### Clinical Reasoning
This child presents with classic new-onset type 1 diabetes complicated by severe DKA. The triad of polyuria, polydipsia, and weight loss reflects hyperglycemia and catabolism from insulin deficiency. DKA criteria are met: glucose >200 mg/dL, pH <7.3 (actually <7.15, indicating severe DKA), bicarbonate <15 mEq/L, and positive ketones. The elevated anion gap reflects unmeasured ketoacids. The HbA1c of 12.8% indicates the hyperglycemia has been present for weeks. The abdominal pain is common in DKA and typically resolves with treatment. Her altered mental status places her at higher risk for cerebral edema.

### Management
1. **Initial fluid resuscitation:** 10 mL/kg NS bolus over 1 hour (not faster due to cerebral edema risk)
2. **Maintenance fluids:** Calculate deficit replacement over 24-48 hours; use 0.45% or 0.9% NS based on sodium trends
3. **Insulin infusion:** Start regular insulin 0.05-0.1 units/kg/hour AFTER initial fluid bolus
4. **Potassium replacement:** Add 40 mEq/L KCl to fluids once K <5.5 mEq/L and patient urinating
5. **Add dextrose:** When glucose reaches 250-300 mg/dL, add D5 or D10 to fluids while continuing insulin until acidosis resolves
6. **Monitoring:** Glucose hourly, BMP Q2-4h, neuro checks Q1h
7. **Cerebral edema precautions:** Head of bed 30 degrees; have mannitol or 3% saline at bedside; watch for headache, altered mental status, bradycardia, hypertension
8. **Transition:** When pH >7.3, bicarbonate >15, patient eating, transition to subcutaneous insulin with basal-bolus regimen
9. **Diabetes education:** Initiate comprehensive education before discharge

### Clinical Image
![Diabetic ketoacidosis presentation](case_01_image.jpg)

**Image Description:** Clinical presentation of diabetic ketoacidosis demonstrating the typical signs of dehydration and metabolic derangement seen in this serious diabetes complication.

**Source:** Wikimedia Commons
**URL:** https://commons.wikimedia.org/wiki/File:Diabetic_ketoacidosis.jpg
**License:** CC BY-SA 4.0

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## Case 2: Congenital Adrenal Hyperplasia - Salt-Wasting Crisis

### Patient Demographics
- **Age:** 12-day-old male
- **Sex:** Male

### Chief Complaint
"He won't eat and seems very weak."

### History of Present Illness
A 12-day-old male is brought to the emergency department with poor feeding, lethargy, and vomiting for 2 days. He was born at term via uncomplicated vaginal delivery. Birth weight was 3.5 kg. He was breastfeeding well initially but has become increasingly difficult to feed over the past 48 hours, with frequent spitting up. Today, he has been very sleepy and difficult to arouse. His diaper has been dry for 8 hours. Newborn screening results are pending. There is no family history of endocrine disorders, but the parents are first cousins.

### Physical Examination
- **General:** Lethargic, weak cry, mottled skin, poor responsiveness
- **Vital signs:** Temp 36.2°C (low), HR 180 bpm, RR 55/min, BP 55/35 mmHg, Weight 3.1 kg (down from 3.5 kg at birth - 11% weight loss)
- **HEENT:** Sunken fontanelle, dry mucous membranes
- **Cardiovascular:** Tachycardic, weak pulses, delayed capillary refill (4 seconds)
- **Respiratory:** Tachypneic, clear lungs
- **Abdomen:** Soft, non-distended
- **Genitourinary:** Normal male external genitalia, normal phallus size, bilateral descended testes
- **Skin:** Hyperpigmented scrotum and nipples

### Workup
- **Point-of-care glucose:** 42 mg/dL (low)
- **BMP:** Na 118 mEq/L (critically low), K 7.8 mEq/L (critically high), Cl 95 mEq/L, HCO3 14 mEq/L, BUN 35 mg/dL, Cr 0.8 mg/dL, Glucose 38 mg/dL
- **VBG:** pH 7.22
- **ECG:** Peaked T waves, widened QRS
- **17-hydroxyprogesterone:** 8,500 ng/dL (markedly elevated; normal <100)
- **Cortisol:** 2.1 mcg/dL (low for stress)
- **ACTH:** 450 pg/mL (markedly elevated)
- **Newborn screen (just resulted):** Elevated 17-OHP flagged

### Diagnosis
**Congenital adrenal hyperplasia (21-hydroxylase deficiency, salt-wasting form) with adrenal crisis**

### Clinical Reasoning
This male infant presents with classic salt-wasting adrenal crisis from 21-hydroxylase deficiency CAH. The presentation at 10-14 days of life is typical, as it takes time for the salt-wasting to become clinically apparent after the protective effect of maternal hormones wears off. The hyponatremia, hyperkalemia, hypoglycemia, and shock reflect both glucocorticoid and mineralocorticoid deficiency. The hyperpigmentation results from ACTH excess (ACTH shares precursors with melanocyte-stimulating hormone). Males present with crisis because they have normal genitalia at birth (unlike virilized females who are often diagnosed earlier) and may not be diagnosed until critically ill.

### Management
1. **Immediate resuscitation:** IV/IO access, NS 20 mL/kg bolus; repeat as needed
2. **Treat hyperkalemia:** Calcium gluconate 100 mg/kg IV (cardioprotection), insulin/glucose, kayexalate if needed
3. **Treat hypoglycemia:** D10W bolus 2 mL/kg, then continuous dextrose infusion
4. **Stress-dose hydrocortisone:** 25 mg IV bolus, then 25 mg IV Q6h (50-100 mg/m²/day)
5. **Mineralocorticoid:** Fludrocortisone 0.1 mg PO daily once stable and able to take orally
6. **Salt supplementation:** NaCl 1-2 g/day in divided doses with feeds
7. **Monitoring:** Frequent electrolytes, glucose; cardiac monitoring
8. **Long-term:** Maintenance hydrocortisone (10-15 mg/m²/day divided TID), fludrocortisone, NaCl supplements; stress dosing education; genetic counseling for family

### Clinical Image
![Adrenal crisis presentation](case_01_image.jpg)

**Image Description:** Clinical presentation demonstrating the metabolic derangements and clinical findings associated with adrenal insufficiency in pediatric patients.

**Source:** Wikimedia Commons
**URL:** https://commons.wikimedia.org/wiki/File:Diabetic_ketoacidosis.jpg
**License:** CC BY-SA 4.0