Endocrine Questions Flashcards
Which of the following is NOT a clinical finding associated with cortisol excess?**
A) Weight gain/growth failure
B) Osteopenia
C) Hypotension
D) Acne, purple striae
Answer:** C) Hypotension
Explanation: Cortisol excess often leads to hypertension, not hypotension
What is a common cause of exogenous glucocorticoid excess?**
A) Autoimmune disease
B) Long-term steroid medication use
C) Pituitary tumor
D) Adrenal tumor
Answer:** B) Long-term steroid medication use
Explanation: Exogenous glucocorticoid excess is commonly due to prolonged use of steroid medications.
Which test is appropriate to diagnose cortisol excess?**
A) Serum aldosterone
B) Serum sodium
C) 24-hour urine for free cortisol
D) ACTH stimulation test
Answer:** C) 24-hour urine for free cortisol
Explanation: A 24-hour urine collection to measure free cortisol is a standard diagnostic test to assess cortisol excess.
In a child with suspected cortisol excess, what symptom would differentiate it from simple obesity?**
A) Weight gain
B) Delayed puberty
C) Increased appetite
D) Normal bone density
Answer:** B) Delayed puberty
Explanation: Delayed puberty can indicate Cushing’s syndrome (a form of cortisol excess), which differentiates it from simple obesity.
Which management strategy should be considered for someone experiencing cortisol excess due to long-term use of glucocorticoids?**
A) Increase calorie intake
B) Initiate high-dose diuretics
C) Wean off steroid doses gradually
D) Start anti-hypertensive medication immediately
Answer:** C) Wean off steroid doses gradually
Explanation: It is essential to gradually taper off glucocorticoid doses to prevent adrenal insufficiency and allow the body to adjust.
A 35-year-old woman presents to the clinic with complaints of persistent weight gain over the past year, despite maintaining a similar diet as before. She reports menstrual irregularities, acne, and noticeable facial swelling. Her blood pressure is 150/95 mmHg.
Questions:
1. Based on the clinical presentation, what condition should be suspected?
2. Which diagnostic test would help confirm your suspicion?
3. If the condition is related to an endogenous source, such as a pituitary tumor, what could the condition be termed?
Answers and Explanations:**
1. Cushing’s Syndrome
- The symptoms of weight gain, especially facial plethora, menstrual irregularities, and hypertension point towards Cushing’s syndrome due to cortisol excess.
-
24-hour urine free cortisol test
- This test would measure the free cortisol levels excreted in urine over 24 hours, confirming if there’s excess cortisol production indicative of Cushing’s syndrome.
-
Cushing’s Disease
- If the cortisol excess is due to an endogenous source such as a pituitary adenoma causing excessive secretion of ACTH, the condition is specifically termed Cushing’s Disease.
A 16-year-old male comes for an evaluation of growth concerns. He has gained significant weight but has seen limited height increase over the past year. On exam, he has hirsutism, purple striae on his abdomen, and his blood pressure is recorded at 160/100 mmHg.
Questions:
1. What potential endocrine disorder does this presentation suggest?
2. What secondary effect of glucocorticoid excess could explain his growth failure?
3. After confirming the diagnosis, what would be the initial management step if he has been on long-term prednisone for another condition?
*Answers and Explanations:**
1. Cushing’s Syndrome
- The combination of growth retardation, weight gain, hirsutism, purple striae, and hypertension suggests hypercortisolism, typical of Cushing’s Syndrome.
-
Suppression of Growth Hormone Secretion
- Cortisol excess can suppress the secretion of growth hormone, leading to growth failure or arrest despite nutritional adequacy.
-
Gradual Tapering of Prednisone
- If the cause is iatrogenic due to long-term prednisone use, the management would involve a gradual tapering of the steroid under medical supervision to allow normal adrenal function to resume.
A 45-year-old male complains of new-onset compulsive eating and difficulties controlling his weight. He also reports low energy, diabetes that has become harder to control, and new hair growth on his body. On examination, you observe a rounded face and ecchymosis on his arms.
Questions:
1. What is a likely initial hypothesis for his symptoms?
2. Which other condition might mimic similar symptoms that should be ruled out initially?
3. Once Cushing’s syndrome is diagnosed, how should the possible cause of endogenous cortisol excess be investigated?
Cushing’s Syndrome**
- The constellation of symptoms—compulsive behavior, weight gain, hyperglycemia, and hair changes suggest excessive cortisol levels that align with Cushing’s syndrome.
-
Obesity
- Obesity can mimic some of these symptoms (e.g., weight gain, diabetes); however, obesity wouldn’t typically present with the other systemic changes, such as spontaneous bruising or facial changes.
-
Blood ACTH Levels and Imaging
- After confirming cortisol excess with appropriate tests, next steps would involve measuring ACTH levels to differentiate between ACTH-dependent and independent causes, alongside imaging studies such as MRI of the pituitary or CT of the adrenal glands for further elucidation.
A 6-month-old infant is brought to the clinic due to a persistent cough, difficulty breathing, and wheezing. The child is frequently positioned in a semi-upright, tripod position. On examination, you notice nasal flaring and intercostal retractions. What is the most likely diagnosis?**
A) Asthma
B) Bronchiolitis
C) Foreign body aspiration
D) Croup
Answer: B) Bronchiolitis**
Explanation:
Bronchiolitis is a common condition in infants usually caused by the respiratory syncytial virus (RSV). It presents with symptoms of upper respiratory infection that progress to cough, wheezing, and respiratory distress. The age and combination of symptoms suggest bronchiolitis rather than asthma (uncommon under the age of 1), foreign body aspiration (often presents acutely), or croup (commonly has a barking cough and stridor).
A 10-year-old boy presents with a sore throat, fever, and tender cervical lymphadenopathy. On examination, you notice a red rash that feels like sandpaper and the presence of a strawberry tongue. Which diagnosis is most likely?**
A) Infectious mononucleosis
B) Scarlet fever
C) Kawasaki disease
D) Hand, foot, and mouth disease
Answer: B) Scarlet fever**
Explanation:
Scarlet fever results from a streptococcal infection and includes a triad of symptoms: a sore throat, fever, and a characteristic “sandpaper” rash, as well as a strawberry tongue. Infectious mononucleosis causes sore throat and lymphadenopathy but not the specific rash. Kawasaki disease also involves strawberry tongue but is associated with prolonged fever and specific criteria for diagnosis. Hand, foot, and mouth disease has vesicular rashes on the hands, feet, and inside the mouth.
An 18-month-old girl presents to the clinic with a fever and rash that started on her trunk three days ago and has now spread to her face and extremities. Her vaccination history is incomplete. The rash is described as erythematous maculopapular. Which disease is most likely?**
A) Roseola
B) Measles
C) Fifth disease
D) Varicella
Answer: B) Measles**
Explanation:
The clinical presentation is suggestive of measles, particularly the progression of the erythematous maculopapular rash beginning on the trunk and spreading to the face and extremities. The patient’s age and incomplete vaccination history increase the suspicion for measles. Roseola typically starts with a high fever and resolves before the rash appears, starting from the trunk and spreading. Fifth disease has a distinctive “slapped cheek” appearance. Varicella (chickenpox) rash is vesicular, not maculopapular.
*A mother is concerned because her 4-month-old infant continually turns his head to one side and has a noticeable flat spot developing on his head. What condition is most likely responsible for these symptoms?**
A) Craniosynostosis
B) Plagiocephaly
C) Torticollis
D) Hydrocephalus
Answer: C) Torticollis**
Explanation:
Torticollis refers to a condition where an infant holds their head tilted to one side, often because of muscular tightness in the neck (congenital muscular torticollis). This can lead to positional plagiocephaly, which is the flattening observed on one side of the head due to the continuous head position. Craniosynostosis involves premature fusion of skull sutures and hydrocephalus is excessive accumulation of cerebrospinal fluid, usually presenting with other symptoms like increased head circumference.
Which vaccine is contraindicated in a child who is known to have a severe allergy to gelatin?**
A) Inactivated Poliovirus Vaccine (IPV)
B) Haemophilus influenzae type b (Hib) vaccine
C) Measles, Mumps, and Rubella (MMR) vaccine
D) Pneumococcal Conjugate Vaccine (PCV13)
C) Measles, Mumps, and Rubella (MMR) vaccine**
Explanation:
The MMR vaccine is contraindicated in individuals with a severe allergy to gelatin, as gelatin is used as a stabilizer in some vaccines. The other vaccines listed generally do not contain gelatin, although formulations can vary; always checking the specific vaccine ingredient list is critical for safety.
What is the most common cause of congenital hypothyroidism in infants in the western world?**
A) Iodine deficiency
B) Thyroidectomy
C) Hashimoto’s thyroiditis
D) Abnormality in thyroid gland development
Answer: D) Abnormality in thyroid gland development**
Explanation:
Congenital hypothyroidism is frequently caused by abnormal development of the thyroid gland or its inability to produce thyroid hormones. This contrasts with acquired hypothyroidism in older children, where Hashimoto’s thyroiditis is a common cause in the western world.
Which of the following symptoms are commonly associated with acquired hypothyroidism in children?**
A) Hypoglycemia and sweating
B) Hyperactivity and rapid growth
C) Delayed puberty and weight gain
D) Tachycardia and tremors
Answer: C) Delayed puberty and weight gain**
Explanation:
Acquired hypothyroidism in children often presents with growth failure, delayed puberty, weight gain, fatigue, dry skin, and other systemic symptoms. These reflect the reduced metabolic activity caused by low thyroid hormone levels.
*A newborn screening reveals elevated TSH levels. What is the next best step in confirming a diagnosis of congenital hypothyroidism?**
A) MRI of the pituitary gland
B) Serum free T4 measurement
C) Conduct an iodine uptake test
D) Perform a bone age study
Answer: B) Serum free T4 measurement**
Explanation:
Following a newborn screening that shows elevated TSH, measuring serum free T4 levels helps confirm congenital hypothyroidism. Elevated TSH with low or normal free T4 levels indicates primary hypothyroidism.
Which physical examination finding is least likely to be present in an infant with congenital hypothyroidism at birth?**
A) Macroglossia
B) Poor feeding
C) Tachypnea
D) Large fontanelles
Answer: C) Tachypnea**
Explanation:
Tachypnea, or rapid breathing, is not typically associated with congenital hypothyroidism. Instead, infants may show symptoms like prolonged jaundice, constipation, macroglossia, poor muscle tone, poor feeding, and potentially large fontanelles.
A 12-year-old child presents with fatigue, weight gain, and dry skin. Laboratory tests show elevated TSH and normal free T4. What is the most likely diagnosis?**
A) Central hypothyroidism
B) Subclinical hypothyroidism
C) Thyroid-binding globulin deficiency
D) Overt (clinical) hypothyroidism
Answer: B) Subclinical hypothyroidism**
Explanation:
Subclinical hypothyroidism is indicated by elevated TSH levels while free T4 remains within the normal range. It can present with symptoms like fatigue and dry skin, although not all individuals show symptoms.
When dealing with hypothyroidism, which condition warrants treatment with levothyroxine in children?**
A) Thyroid Binding Globulin (TBG) deficiency
B) Subclinical hypothyroidism with normal Free T4
C) TSH elevation with low Free T4
D) Central hypothyroidism with normal Free T4
Answer: C) TSH elevation with low Free T4**
Explanation:
Treatment with levothyroxine is indicated when there is an elevation in TSH along with a low free T4, suggestive of primary hypothyroidism. TBG deficiency does not require treatment, and central hypothyroidism often presents with normal or low TSH and should be referred for evaluation.
What is the recommended levothyroxine dosage range for an infant aged 0-3 months with hypothyroidism?**
A) 2-3 mcg/kg/day
B) 5-6 mcg/kg/day
C) 6-8 mcg/kg/day
D) 10-15 mcg/kg/day
Answer: D) 10-15 mcg/kg/day**
Explanation:
For infants aged 0-3 months, the recommended dosage is 10-15 mcg/kg/day. This period requires a relatively higher dose to support rapid growth and development.
Which dosage is appropriate for a child aged 6-12 years who needs levothyroxine therapy?**
A) 2-3 mcg/kg/day
B) 4-5 mcg/kg/day
C) 6-8 mcg/kg/day
D) 5-6 mcg/kg/day
Answer: B) 4-5 mcg/kg/day**
Explanation:
Children aged 6-12 years require a dosage of 4-5 mcg/kg/day to ensure appropriate thyroid hormone levels for growth and metabolism.
At what recommended dosage range should levothyroxine be prescribed for an adolescent older than 12 years?**
A) 2-3 mcg/kg/day
B) 5-6 mcg/kg/day
C) 8-10 mcg/kg/day
D) 10-15 mcg/kg/day
Answer: A) 2-3 mcg/kg/day**
Explanation:
For adolescents older than 12 years, the recommended levothyroxine dosage is 2-3 mcg/kg/day, reflecting the decrease in dose required as children age and their growth rates stabilize.
How does the levothyroxine dosage for an infant aged 6-12 months compare to that of an infant aged 3-6 months?**
A) They are the same
B) The dosage is higher for 6-12 months
C) The dosage is lower for 3-6 months
D) The dosage steadily increases with age
Answer: B) The dosage is higher for 6-12 months**
Explanation:
For an infant aged 6-12 months, the dosage is 6-8 mcg/kg/day, which is higher compared to 8-10 mcg/kg/day for infants aged 3-6 months. As infants grow, their dosage initially increases before decreasing again with age.
Which age group should receive 5-6 mcg/kg/day of levothyroxine?**
A) 0-3 months
B) 3-6 months
C) 1-5 years
D) 6-12 years
*Answer: C) 1-5 years**
What is the appropriate levothyroxine dosage range for an infant aged 0-3 months?**
A) 5-6 mcg/kg/day
B) 8-10 mcg/kg/day
C) 10-15 mcg/kg/day
D) 2-3 mcg/kg/day
*Answer: C) 10-15 mcg/kg/day**
Explanation:
Infants aged 0-3 months require 10-15 mcg/kg/day to support rapid development.
What dosage of levothyroxine is recommended for an infant aged 3-6 months?**
A) 2-3 mcg/kg/day
B) 8-10 mcg/kg/day
C) 6-8 mcg/kg/day
D) 10-15 mcg/kg/day
*Answer: B) 8-10 mcg/kg/day**
Explanation:
The dosage for infants aged 3-6 months is 8-10 mcg/kg/day, reflecting slightly reduced needs as compared to newborns
