Endocrinology Practice Questions

Q: What is the disease this child, who also has hepatosplenomegaly and intellectual disability, is suffering from?

Mucopolysaccharidosis. ***Mucopolysaccharidosis*** - The triad of **coarse facial features**, **hepatosplenomegaly**, and **intellectual disability** is characteristic of mucopolysaccharidosis, particularly **Hurler syndrome** (MPS I). - This lysosomal storage disorder causes accumulation of **glycosaminoglycans**, leading to progressive multisystem involvement including skeletal abnormalities and organomegaly. *Gaucher disease* - **Type 1 Gaucher disease** (most common) typically presents with hepatosplenomegaly but **no CNS involvement** or intellectual disability. - Patients usually have **normal facial features** and lack the coarse facies seen in mucopolysaccharidoses. *Phenylketonuria* - Causes **intellectual disability** and developmental delays but does **not cause hepatosplenomegaly** or organomegaly. - Results from **phenylalanine hydroxylase deficiency**, leading to toxic accumulation of phenylalanine metabolites affecting brain development. *Krabbe's disease* - A **leukodystrophy** that primarily affects white matter, causing severe neurological deterioration and intellectual disability. - Does **not cause hepatosplenomegaly** and presents mainly with progressive neurological symptoms and spasticity.

Q: Which of the following is a common presentation of juvenile hypothyroidism?

Growth retardation. **Explanation:** **Juvenile Hypothyroidism** refers to hypothyroidism acquired after the period of infancy (usually after 2 years of age). Unlike congenital hypothyroidism, the clinical presentation is often subtle and insidious. 1. **Why Growth Retardation is Correct:** The hallmark of juvenile hypothyroidism is a **deceleration in growth velocity**, leading to short stature. Thyroid hormones are essential for linear bone growth and skeletal maturation. A key clinical finding is that the **bone age is significantly delayed** compared to the chronological age. This is often the earliest and most common reason for presentation in clinical practice. 2. **Analysis of Incorrect Options:** * **Mental Retardation (B):** This is a feature of **Congenital Hypothyroidism** if not treated within the first few weeks of life. In juvenile hypothyroidism, the brain is already developed, so while children may show sluggishness or poor school performance, permanent intellectual disability (mental retardation) does not occur. * **Delayed Puberty (C):** While hypothyroidism can cause delayed puberty, it is classically associated with **Precocious Puberty** (Van Wyk-Grumbach Syndrome). High levels of TSH can cross-react with FSH receptors, leading to early breast development or testicular enlargement. * **Umbilical Hernia (D):** This is a classic sign of **Congenital Hypothyroidism** (infantile presentation), along with a large tongue and prolonged jaundice, rather than the juvenile form. **High-Yield NEET-PG Pearls:** * **Most common cause:** Hashimoto’s Thyroiditis (Autoimmune). * **Earliest Sign:** Growth failure (falling across centiles on a growth chart). * **Dental Sign:** Delayed eruption of permanent teeth. * **Van Wyk-Grumbach Syndrome:** Triad of Juvenile Hypothyroidism, Precocious Puberty, and Delayed Bone Age.

Q: A 2-week-old infant presents with protracted vomiting and poor oral intake. Examination reveals signs of dehydration and ambiguous genitalia. Serum electrolytes show hyponatremia, hypochloremia, and normal bicarbonate. Which of the following is the most common cause of ambiguous genitalia in this context?

21-hydroxylase deficiency. **Explanation:** The clinical presentation of a neonate with **protracted vomiting, dehydration, and ambiguous genitalia** (virilization in a female) strongly suggests **Congenital Adrenal Hyperplasia (CAH)**. **1. Why 21-hydroxylase deficiency is correct:** This is the most common cause of CAH (>90% of cases). A deficiency in this enzyme impairs the conversion of progesterone to deoxycorticosterone (mineralocorticoid pathway) and 17-OH progesterone to 11-deoxycortisol (glucocorticoid pathway). * **Salt-wasting:** Lack of aldosterone leads to hyponatremia, hyperkalemia (though this patient has hypochloremia, the electrolyte shift is classic for salt-wasting), and dehydration. * **Virilization:** Shunting of precursors into the androgen pathway causes ambiguous genitalia in 46,XX females. **2. Why other options are incorrect:** * **11-hydroxylase deficiency:** While it causes virilization, it leads to the accumulation of 11-deoxycorticoserone (a weak mineralocorticoid), which typically causes **hypertension and hypokalemia**, rather than salt-wasting and dehydration. * **5-alpha-reductase deficiency:** This affects 46,XY males, causing undervirilization (female-appearing or ambiguous external genitalia). It does **not** cause electrolyte imbalances or vomiting. * **Maternal ingestion of drugs:** While this can cause virilization of a female fetus, it would not cause the systemic "salt-wasting crisis" (vomiting/dehydration) seen in this infant. **High-Yield Clinical Pearls for NEET-PG:** * **Gold Standard Diagnosis:** Elevated serum **17-hydroxyprogesterone (17-OHP)** levels. * **Classic Electrolyte Triad:** Hyponatremia, Hyperkalemia, and Metabolic Acidosis. * **Karyotype:** Most infants with CAH and ambiguous genitalia are **46,XX** (genotypic females). * **Management:** Immediate fluid resuscitation and replacement of glucocorticoids (Hydrocortisone) and mineralocorticoids (Fludrocortisone).

Q: The features of neonatal hyperthyroidism include all except?

Goiter is rare. **Explanation:** Neonatal hyperthyroidism (Neonatal Graves' Disease) is a rare but serious condition typically caused by the transplacental passage of maternal **Thyroid Stimulating Immunoglobulins (TSI)**. **Why "Goiter is rare" is the correct (incorrect statement) answer:** In neonatal hyperthyroidism, **goiter is actually a common and characteristic finding**. The maternal antibodies (TSI) stimulate the fetal thyroid gland, leading to hyperplasia and enlargement. A large goiter in a neonate can occasionally cause airway obstruction or interfere with swallowing. **Analysis of other options:** * **Triangular facies and Craniosynostosis:** Chronic exposure to excess thyroid hormones in utero or early infancy accelerates bone growth. This leads to premature fusion of cranial sutures (craniosynostosis) and a characteristic triangular facial appearance (frontal bossing with a pointed chin). * **Congestive Cardiac Failure (CCF):** Hyperthyroidism induces a hyperdynamic state. Neonates often present with severe tachycardia, arrhythmias, and high-output cardiac failure, which is a leading cause of mortality if untreated. * **Advanced Osseous Maturation:** Thyroid hormone is a potent stimulator of bone maturation. Affected neonates often show advanced bone age on X-rays (e.g., presence of the distal femoral epiphysis earlier than expected). **Clinical Pearls for NEET-PG:** * **Etiology:** Most cases are transient, resolving in 3–12 weeks as maternal antibodies are cleared from the infant's circulation. * **Clinical Features:** Irritability, poor weight gain despite polyphagia (voracious appetite), exophthalmos, and hepatosplenomegaly. * **Treatment:** The drug of choice is **Methimazole**. Propranolol is used to manage tachycardia/CCF, and Lugol’s iodine may be used to acutely inhibit hormone release.

Q: Features of Laurence-Moon-Bardet-Biedl syndrome include all of the following EXCEPT?

Cataract. **Explanation:** Laurence-Moon-Bardet-Biedl (LMBB) syndrome is a rare autosomal recessive ciliopathy characterized by multi-system involvement. The correct answer is **Cataract**, as it is not a classic feature of this syndrome. Instead, the hallmark ocular finding is **Retinitis Pigmentosa** (rod-cone dystrophy), which leads to night blindness and progressive vision loss. **Analysis of Options:** * **Hypogonadism (Option A):** This is a primary feature, often manifesting as delayed puberty, small genitalia, or infertility due to hypogonadotropic hypogonadism. * **Obesity (Option B):** Truncal obesity is one of the most common and earliest signs, typically appearing in early childhood. * **Polydactyly (Option C):** Post-axial polydactyly (extra digits on the ulnar/fibular side) is a classic diagnostic criterion. * **Cataract (Option D):** While vision is affected, it is due to retinal degeneration, not lens opacification. Therefore, Cataract is the "Except" option. **Clinical Pearls for NEET-PG:** * **The "Pentad" of LMBB:** 1. Obesity, 2. Hypogonadism, 3. Polydactyly, 4. Retinitis Pigmentosa, 5. Mental Retardation (Intellectual disability). * **Renal Involvement:** Chronic renal failure is the most common cause of morbidity and mortality in these patients. * **Distinction:** Historically, **Laurence-Moon** was associated with spastic paraplegia and no polydactyly, while **Bardet-Biedl** featured polydactyly and obesity. They are now often grouped together as a spectrum. * **Mnemonic:** Remember **"PRORH"** (Polydactyly, Retinitis pigmentosa, Obesity, Renal failure, Hypogonadism).

Q: A newborn baby presents with tachycardia, hypotension, and irritability. USG revealed normal ovaries, and the karyotype is 46,XX. Which of the following biochemical abnormalities is not typically seen in this clinical scenario?

Hyperglycemia. **Explanation:** The clinical presentation of a newborn with tachycardia, hypotension (signs of shock), and irritability, combined with a **46,XX karyotype** and normal ovaries, is classic for **Congenital Adrenal Hyperplasia (CAH)**, most commonly due to **21-hydroxylase deficiency**. **1. Why Hyperglycemia is the Correct Answer:** In 21-hydroxylase deficiency, there is a block in the conversion of progesterone to deoxycorticosterone and 17-hydroxyprogesterone to 11-deoxycortisol. This leads to a **deficiency in Cortisol**. Since cortisol is a counter-regulatory hormone that promotes gluconeogenesis and glycogenolysis, its absence leads to **Hypoglycemia**, not hyperglycemia. Therefore, hyperglycemia is not typically seen in this scenario. **2. Analysis of Incorrect Options:** * **Hyponatremia & Hyperkalemia:** These occur due to **Aldosterone deficiency**. Aldosterone normally reabsorbs sodium and excretes potassium/hydrogen ions in the distal tubule. Its absence leads to "salt-wasting," resulting in low sodium and high potassium. * **Hypoglycemia:** As explained above, this is a direct result of glucocorticoid (cortisol) deficiency. **Clinical Pearls for NEET-PG:** * **Most Common Cause:** 21-hydroxylase deficiency (90-95% of CAH cases). * **Diagnostic Marker:** Elevated levels of **17-hydroxyprogesterone (17-OHP)**. * **Genitalia:** In 46,XX females, excess androgens cause **ambiguous genitalia** (virilization), though internal organs (ovaries/uterus) remain normal. * **Management:** Acute adrenal crisis requires aggressive fluid resuscitation (Normal Saline) and IV Hydrocortisone. * **Karyotype Tip:** Always look for the mismatch between karyotype (46,XX) and physical signs of virilization to spot CAH questions.

Q: Inheritance pattern of Familial hypophosphatemic Rickets is:

X-linked dominant. **Explanation:** **Familial Hypophosphatemic Rickets (FHR)**, also known as Vitamin D-resistant rickets, is most commonly caused by a mutation in the **PHEX gene** (Phosphate regulating gene with Homologies to endopeptidases on the X chromosome). 1. **Why X-linked Dominant is Correct:** The PHEX mutation leads to increased levels of **FGF-23** (Fibroblast Growth Factor-23), a phosphaturic hormone. Excess FGF-23 inhibits renal phosphate reabsorption and suppresses the activation of Vitamin D (1-alpha-hydroxylase activity). Because it is **X-linked dominant**, the condition is expressed in both hemizygous males and heterozygous females. It is one of the classic examples of X-linked dominant inheritance frequently tested in NEET-PG. 2. **Why Other Options are Incorrect:** * **Autosomal Recessive/Dominant:** While rare forms of hypophosphatemic rickets exist (e.g., ADHR or ARHR), the "Familial" or "Classic" form specifically refers to the X-linked variety. * **X-linked Recessive:** In FHR, a single mutant allele on the X chromosome is sufficient to cause the clinical phenotype in females; therefore, it is not recessive. **High-Yield Clinical Pearls for NEET-PG:** * **Biochemical Profile:** Low serum phosphate, **Normal** serum calcium, **Normal** 25(OH)D, but inappropriately low/normal 1,25(OH)₂D, and **Elevated Alkaline Phosphatase**. * **Clinical Feature:** Unlike nutritional rickets, **rachitic rosary and tetany are rare**; the primary manifestation is lower limb bowing and short stature. * **Treatment:** Oral phosphate supplementation and **Calcitriol** (active Vitamin D). * **Rule of Thumb:** If a question mentions "Rickets non-responsive to Vitamin D," think of FHR or Vitamin D Dependent Rickets (VDDR).

Q: The parents of a 4-week-old girl complain that their baby is apathetic and sluggish. On physical examination, the child's abdomen is large and exhibits an umbilical hernia. The skin is pale and cold, and the temperature is 35°C (95°F). Which of the following provides a plausible explanation for the signs and symptoms of this child?

Thyroid agenesis. **Explanation:** The clinical presentation of apathy, sluggishness, an umbilical hernia, a protuberant abdomen, and hypothermia (35°C) in a 4-week-old infant is a classic description of **Congenital Hypothyroidism**. **1. Why Thyroid Agenesis is Correct:** Thyroid dysgenesis (which includes **agenesis**, hypoplasia, or ectopy) is the most common cause of permanent congenital hypothyroidism (85%). Thyroid hormones are essential for metabolic rate and thermogenesis; hence, deficiency leads to hypothermia and cold, pale skin. The "sluggishness" reflects CNS depression and decreased metabolic activity. Other classic signs include a large fontanelle, macroglossia, and a characteristic umbilical hernia due to hypotonia of the abdominal muscles. **2. Why Incorrect Options are Wrong:** * **Cystic Fibrosis:** Typically presents with meconium ileus in neonates or failure to thrive and recurrent pneumonia later. It does not cause umbilical hernia or significant hypothermia. * **Muscular Dystrophy:** Duchenne or Becker muscular dystrophy usually manifests in early childhood (3–5 years) with motor delays, not as a multisystem metabolic collapse in a 4-week-old. * **Parathyroid Hyperplasia:** This would lead to hypercalcemia. While it can cause lethargy, it does not explain the umbilical hernia or the specific cutaneous and thermoregulatory findings seen here. **Clinical Pearls for NEET-PG:** * **Most common cause worldwide:** Iodine deficiency. * **Most common cause in non-endemic areas:** Thyroid dysgenesis (Agenesis is the most severe form). * **Screening:** Done via heel-prick test (TSH levels) at 48–72 hours of life. * **Treatment:** Levothyroxine must be started immediately to prevent permanent **neurocognitive impairment (Cretinism)**. * **Early Sign:** Prolonged physiological jaundice is often the earliest clinical clue.

Question 1

What is the disease this child, who also has hepatosplenomegaly and intellectual disability, is suffering from?

Accepted Answer

Mucopolysaccharidosis

Answer

Gaucher disease

Answer

Phenylketonuria

Answer

Krabbe's disease

Question 2

Which of the following is a common presentation of juvenile hypothyroidism?

Accepted Answer

Growth retardation

Answer

Mental retardation within 2 years

Answer

Delayed puberty

Answer

Umbilical hernia

Question 3

A 2-week-old infant presents with protracted vomiting and poor oral intake. Examination reveals signs of dehydration and ambiguous genitalia. Serum electrolytes show hyponatremia, hypochloremia, and normal bicarbonate. Which of the following is the most common cause of ambiguous genitalia in this context?

Accepted Answer

21-hydroxylase deficiency

Answer

5-alpha-reductase deficiency

Answer

11-hydroxylase deficiency

Answer

Maternal ingestion of virilizing drugs during pregnancy

Question 4

The features of neonatal hyperthyroidism include all except?

Accepted Answer

Goiter is rare

Answer

Triangular facies with craniosynostosis

Answer

Congestive cardiac failure

Answer

Advanced osseous maturation

Question 5

Features of Laurence-Moon-Bardet-Biedl syndrome include all of the following EXCEPT?

Accepted Answer

Cataract

Answer

Hypogonadism

Answer

Obesity

Answer

Polydactyly

Question 6

A 2-year-old child presents with a history of drowsiness, progressing to unconsciousness and seizures. On evaluation, the blood glucose level is found to be 25 mg/dL. Following the administration of 5 mL/kg of dextrose, there is no improvement. A repeat blood glucose measurement shows the level has risen to 130 mg/dL. Considering this clinical scenario, which of the following interventions could be detrimental?

Accepted Answer

2.5 mL/kg of 10% dextrose

Answer

Inhaled oxygen

Answer

Levetiracetam

Answer

Dexamethasone

Question 7

A newborn baby presents with tachycardia, hypotension, and irritability. USG revealed normal ovaries, and the karyotype is 46,XX. Which of the following biochemical abnormalities is not typically seen in this clinical scenario?

Accepted Answer

Hyperglycemia

Answer

Hypoglycemia

Answer

Hyponatremia

Answer

Hyperkalemia

Question 8

Inheritance pattern of Familial hypophosphatemic Rickets is:

Accepted Answer

X-linked dominant

Answer

Autosomal recessive

Answer

X-linked recessive

Answer

Autosomal dominant

Question 9

Ambiguous genitalia in males is due to which of the following conditions?

Accepted Answer

5-alpha reductase deficiency

Answer

Congenital adrenal hyperplasia

Answer

Cushing's disease

Answer

Aromatase deficiency

Question 10

The parents of a 4-week-old girl complain that their baby is apathetic and sluggish. On physical examination, the child's abdomen is large and exhibits an umbilical hernia. The skin is pale and cold, and the temperature is 35°C (95°F). Which of the following provides a plausible explanation for the signs and symptoms of this child?

Accepted Answer

Thyroid agenesis

Answer

Cystic fibrosis

Answer

Muscular dystrophy

Answer

Parathyroid hyperplasia

Endocrinology — MCQs

Endocrinology — MCQs

On this page

Practice by Chapter

Want unlimited practice?