Pediatric Endocrine Disorders

A 4-day-old male infant is brought to the emergency department due to poor feeding, excessive sleepiness, and jittery movements. He was born at 39 weeks of gestation via uncomplicated vaginal delivery to a 28-year-old primigravid mother. Vital signs show a temperature of 36.1°C (97.0°F), heart rate of 165/min, respiratory rate of 45/min, and blood pressure of 58/36 mmHg. Physical examination reveals a lethargic neonate with mild scleral icterus. Genitourinary examination shows bilateral nonpalpable testes and a stretched penile length of 1.4 cm (normal for term > 2.5 cm). Laboratory studies reveal a capillary blood glucose of 34 mg/dL. He is given an intravenous dextrose bolus with improvement in his symptoms. Additional laboratory results are as follows:

Which of the following is the most likely diagnosis?

Match each pediatric patient's clinical presentation with the most likely underlying diagnosis.

A 6-year-old girl is brought to the pediatric endocrinology clinic by her parents due to breast development and rapid growth over the past 6 months. Physical examination reveals Tanner stage 3 breast development and Tanner stage 2 pubic hair. Her height has recently crossed from the 50th to the 95th percentile for age. Assuming her evaluation ultimately leads to a diagnosis of idiopathic central precocious puberty requiring pharmacotherapy, arrange the following clinical steps in the correct chronological order from initial diagnostic evaluation to final management.

A 6-year-old girl is brought to the clinic by her parents due to bilateral breast development and a recent rapid increase in height. Her past medical history is unremarkable. Physical examination reveals Tanner stage 3 breast development and Tanner stage 2 pubic hair. Assume each subsequent test in her workup yields findings that require progression to the next definitive step in the standard diagnostic and therapeutic algorithm for central precocious puberty.

Arrange the following steps in the most appropriate sequential order for the evaluation and management of this patient.

A $7$-year-old female patient is seen in the pediatric endocrinology office for an evaluation of early physical maturation. The parents first noticed the development of breast tissue about $8$ months ago. Recently, she has outgrown her clothes much faster than her peers. On physical examination, her height is at the $95$ th percentile, whereas she had historically tracked along the $50$ th percentile. She has Tanner stage $3$ breasts and Tanner stage $2$ pubic hair. Radiographic assessment of the left wrist indicates a skeletal age of $10$ years. A random serum luteinizing hormone (LH) level is markedly elevated. Which of the following is the most appropriate next step in the evaluation of this patient?

A macrosomic male infant born at $39$ weeks gestation develops persistent hypoglycemia. At $24$ hours of life, despite receiving a continuous intravenous infusion of $10\%$ dextrose at a glucose infusion rate (GIR) of $8$ mg/kg/min, his point-of-care blood glucose is $40$ mg/dL. He is lethargic but maintaining his airway and hemodynamic stability. The medical team suspects congenital hyperinsulinism and prepares to definitively evaluate and manage his condition.

Arrange the following steps in the optimal sequential order for the diagnostic workup and management of this patient.

Pair the following pediatric clinical presentations and laboratory findings with their corresponding endocrine diagnoses.

Review the following pediatric case scenarios involving abnormal physical findings or thyroid function laboratory results. Pair each patient profile with the correct underlying endocrine etiology.

A 9-year-old boy is brought to the clinic for evaluation of poor growth. Over the past 2 years, his height has decreased from the 50th to the 5th percentile, while his weight has increased from the 50th to the 75th percentile. The patient also complains of being constantly tired, feeling cold, and waking up 3 to 4 times a night to urinate and drink water. He has no significant past medical history. His temperature is $36.2^\circ\text{C}$, blood pressure is $90/60\text{ mmHg}$, and pulse is $58/\text{min}$. Physical examination shows dry skin and delayed relaxation of the deep tendon reflexes. He is at Tanner stage 1 for pubic hair and genital development.

Laboratory results are as follows:

Which of the following is the most likely etiology of this patient's current condition?

A 5-day-old female neonate is evaluated in the nursery for persistent tachycardia, irritability, and poor weight gain. She was born at 38 weeks gestation via spontaneous vaginal delivery. Her current weight is 2.8 kg, down from a birth weight of 3.2 kg. Vital signs show a temperature of $37.5^\circ\text{C}$ ($99.5^\circ\text{F}$), heart rate of $192/\text{min}$, and respiratory rate of $52/\text{min}$. Physical examination reveals a restless infant with warm, flushed skin and a wide-eyed stare. The mother has a history of Graves disease and was treated with a total thyroidectomy four years ago; she takes levothyroxine daily and maintained normal thyroid hormone levels throughout her pregnancy. Laboratory studies of the infant demonstrate a thyroid-stimulating hormone (TSH) level of $<0.01\ \mu\text{U/mL}$ and an elevated free thyroxine (T4) level. Which of the following is the most likely underlying mechanism for this neonate's clinical presentation?

An $8$-year-old boy is brought to the emergency department by his parents due to abdominal pain, nausea, vomiting, and progressive lethargy over the past $24$ hours. The parents report that he has been drinking excessive amounts of water and urinating frequently for the past three weeks. On physical examination, he is lethargic but arousable, tachycardic, and has deep, rapid respirations with a fruity breath odor. Capillary blood glucose is measured at $480 \text{ mg/dL}$. Arrange the following steps in the most appropriate chronological sequence for the initial acute management of this patient's condition.

A 14-year-old boy is brought to the clinic for evaluation of worsening fatigue, cold intolerance, and constipation over the past 4 months. He has also experienced frequent morning nausea and lightheadedness when standing up quickly. His parents note that his growth has slowed significantly over the past year. Eight months ago, the patient was involved in a severe motor vehicle collision that resulted in a traumatic brain injury requiring a 3-week intensive care unit stay. His height is at the 15th percentile and his weight is at the 35th percentile. Blood pressure is $90/60 \text{ mm Hg}$ while sitting and drops to $75/50 \text{ mm Hg}$ upon standing.

Laboratory evaluation reveals:
- Sodium: $132 \text{ mEq/L}$
- Potassium: $4.0 \text{ mEq/L}$
- Thyroid-stimulating hormone (TSH): $1.4 \text{ \mu U/mL}$ (Normal: $0.5 - 4.5 \text{ \mu U/mL}$)
- Free T4: $0.5 \text{ ng/dL}$ (Normal: $0.9 - 1.7 \text{ ng/dL}$)

Which of the following is the most appropriate next step in the management of this patient?

Match the following clinical and laboratory profiles of pediatric patients to the most likely underlying endocrine disorder.

Match the following clinical presentations of suspected adrenal enzyme deficiencies with their most likely underlying diagnosis. Evaluate both the mineralocorticoid status and the degree of virilization to determine the correct enzyme defect.

An $8$-month-old boy is evaluated in the pediatric emergency department for irritability, poor feeding, and passing copious amounts of dilute-appearing urine over the past three days. His parents report that he frequently demands breast milk or water but often vomits shortly afterward. His birth and prenatal history were unremarkable. He is currently at the $5$ th percentile for weight and $25$ th percentile for length, having dropped from the $50$ th percentile for weight at his $4$-month visit. Temperature is $37.1^\circ\text{C}$ ($98.8^\circ\text{F}$), blood pressure is $85/50 \text{ mm Hg}$, and pulse is $160/\text{min}$. Physical examination shows dry mucous membranes, a sunken anterior fontanelle, and poor skin turgor. Initial laboratory studies show:

Serum sodium: $154 \text{ mEq/L}$
Serum potassium: $4.0 \text{ mEq/L}$
Serum osmolality: $318 \text{ mOsm/kg H}_2\text{O}$
Urine osmolality: $95 \text{ mOsm/kg H}_2\text{O}$

The patient is admitted, and subcutaneous desmopressin is administered. Two hours later, a repeat urine osmolality is $105 \text{ mOsm/kg H}_2\text{O}$. Which of the following is the most appropriate long-term pharmacotherapy to reduce polyuria in this patient?

A $9$-month-old boy is brought to the clinic for a routine evaluation. His parents are concerned because he is not yet sitting without support and seems less active than his older siblings were at this age. He was born at $40$ weeks gestation following an uncomplicated pregnancy. The state newborn screening, which utilizes a primary thyroid-stimulating hormone (TSH) assay, was reported as normal. Over the last six months, his length has fallen from the $50$ th to the $5$ th percentile, and his weight has fallen from the $40$ th to the $10$ th percentile. On physical examination, the infant has generalized hypotonia, a prominent forehead, and a remarkably small phallus.

Laboratory testing reveals the following:

Which of the following is the most likely underlying cause of this patient's clinical and laboratory findings?

A $12$-year-old adolescent is brought to the emergency triage in a lethargic state. The parents note a three-week history of unquenchable thirst, frequent nighttime urination, and a $4\text{-kg}$ weight loss. Clinical examination reveals deep, rapid respirations and a heart rate of $135\text{/min}$. Point-of-care testing shows a capillary blood glucose of $580 \text{ mg/dL}$. A venous blood gas demonstrates a pH of $7.08$ and a calculated anion gap of $24 \text{ mEq/L}$. The patient is diagnosed with severe diabetic ketoacidosis (DKA). Arrange the following therapeutic interventions in the appropriate chronological order, reflecting the standard pediatric endocrine protocol to safely correct the metabolic derangement while minimizing the risk of cerebral edema.

An 8-year-old girl is referred to the pediatric endocrinology clinic for evaluation of growth failure. Her parents report that she is the shortest in her class and has not needed a larger shoe size or new clothing sizes in the past two years. Review of her growth chart shows a height that has crossed two major percentile lines downward over the last 30 months, currently resting below the 1st percentile. Her weight is tracking consistently at the 45th percentile. She has no history of headaches, visual changes, gastrointestinal symptoms, or cold intolerance. Physical examination is unremarkable, with normal visual fields and Tanner stage 1 pubertal development. Arrange the following diagnostic and management steps in the most appropriate chronological order for evaluating this patient's growth deceleration.

During a routine kindergarten physical, the physician notes that a 5-year-old boy has grown significantly faster than his peers. His parents report that he has developed axillary hair and adult-like body odor over the last six months. He is otherwise healthy and takes no medications. Vital signs show a blood pressure of $134/86\text{ mm Hg}$ (greater than the 99th percentile for his age and height). Physical examination reveals a muscular habitus and moderate facial acne. Genitourinary examination demonstrates Tanner stage III pubic hair, an enlarged phallus, and bilateral testicular volumes of $2\text{ mL}$. Radiographic imaging of the left wrist indicates a bone age of 9 years, and his serum testosterone is markedly elevated. Which of the following laboratory abnormalities is most likely to be found in this patient?

Match each clinical presentation of a pediatric patient with the most likely underlying endocrine condition.