Hyperparathyroidism — MCQs
A 45-year-old man undergoes a parathyroidectomy given recurrent episodes of dehydration and kidney stones caused by hypercalcemia secondary to an elevated PTH level. He is recovering on the surgical floor on day 3. His temperature is 97.6°F (36.4°C), blood pressure is 122/81 mmHg, pulse is 84/min, respirations are 12/min, and oxygen saturation is 98% on room air. The patient is complaining of perioral numbness currently. What is the most appropriate management of this patient?
Secondary hyperparathyroidism due to Vit D deficiency shows :
All are true about primary hyperparathyroidism except which of the following?
Primary Hyperparathyroidism is associated with -
Which hormone increases with age?
All the following are seen in Hyperparathyroidism except:
A 45-year-old man presents with back pain and facial pain. Physical examination reveals coarse facial features and kyphosis. Laboratory examination shows elevated alkaline phosphatase. Radiographic studies demonstrate skull thickening with narrowing of foramina, and bowing of the femur and tibia. Bone biopsy reveals a mosaic pattern of bone spicules with prominent osteoid seams. Which of the following neoplasms occurs with increased frequency in patients with this disorder?
Splaying and cupping of the metaphysis is seen in which of the following conditions?
Bone density is decreased in which of the following conditions?
A 40-year-old female presents with urine darkening on standing, joint pain and stiffness, and pigment deposition in joints. What is the probable diagnosis?
Hyperparathyroidism Indian Medical PG Practice Questions and MCQs
Question 1: A 45-year-old man undergoes a parathyroidectomy given recurrent episodes of dehydration and kidney stones caused by hypercalcemia secondary to an elevated PTH level. He is recovering on the surgical floor on day 3. His temperature is 97.6°F (36.4°C), blood pressure is 122/81 mmHg, pulse is 84/min, respirations are 12/min, and oxygen saturation is 98% on room air. The patient is complaining of perioral numbness currently. What is the most appropriate management of this patient?
- A. Potassium
- B. TSH level
- C. Vitamin D
- D. Observation
- E. Calcium gluconate (Correct Answer)
Explanation: ***Calcium gluconate*** - The patient's presentation of **perioral numbness** following a parathyroidectomy, especially given a history of hypercalcemia, is highly suggestive of **hypocalcemia**. - **Calcium gluconate** is indicated for acute symptomatic hypocalcemia to rapidly raise serum calcium levels and alleviate symptoms. *Potassium* - There is no clinical indication for **potassium** supplementation; the symptom of perioral numbness is not associated with potassium imbalance. - Parathyroidectomy and hypercalcemia primarily affect calcium and phosphate metabolism, not typically potassium. *TSH level* - A **TSH level** is used to assess thyroid function, which is generally not directly affected by parathyroidectomy unless thyroid tissue was incidentally damaged. - The symptoms presented do not suggest a thyroid dysfunction. *Vitamin D* - While **vitamin D** is crucial for calcium absorption and might be used in chronic management of hypocalcemia, it would not provide the immediate relief needed for acute symptomatic hypocalcemia. - Acute symptoms like perioral numbness require a rapid elevation of serum calcium. *Observation* - **Observation** is inappropriate given the patient's symptomatic presentation of **perioral numbness**, which indicates acute and potentially worsening hypocalcemia. - Untreated symptomatic hypocalcemia can progress to more severe complications such as seizures, arrhythmias, and laryngospasm.
Question 2: Secondary hyperparathyroidism due to Vit D deficiency shows :
- A. Hypocalcemia (Correct Answer)
- B. Hypophosphatemia
- C. Hypercalcemia
- D. Hyperphosphatemia
Explanation: ***Hypocalcemia*** - **Vitamin D deficiency** leads to decreased intestinal absorption of calcium, causing **hypocalcemia** [3]. - This persistent **low serum calcium** is the primary stimulus for the parathyroid glands to increase PTH secretion, leading to secondary hyperparathyroidism [1], [2]. *Hypophosphatemia* - While PTH typically promotes phosphate excretion in the kidneys leading to hypophosphatemia, in **secondary hyperparathyroidism due to vitamin D deficiency**, the effect on phosphate can be variable [3]. - The goal of increased PTH is to raise calcium, and maintaining some level of phosphate is necessary for bone health and proper calcium regulation. Early or mild deficiency may not show significant hypophosphatemia. *Hypercalcemia* - **Hypercalcemia** is a characteristic feature of **primary hyperparathyroidism**, where the parathyroid glands autonomously overproduce PTH [1]. - In secondary hyperparathyroidism (due to vitamin D deficiency), the PTH is elevated in response to **low calcium**, and sustained significant hypercalcemia is not expected; in fact, the underlying problem is **hypocalcemia** [1]. *Hyperphosphatemia* - **PTH** generally acts to lower serum phosphate levels by promoting its renal excretion [2]. - Therefore, **hyperphosphatemia** is not typically observed in secondary hyperparathyroidism; rather, a more common finding would be normal or low phosphate due to the elevated PTH [3].
Question 3: All are true about primary hyperparathyroidism except which of the following?
- A. Nephrolithiasis
- B. Loss of lamina dura
- C. Decreased calcium (Correct Answer)
- D. Increased alkaline phosphatase
Explanation: ***Decreased calcium*** - Primary hyperparathyroidism is characterized by **excessive parathyroid hormone (PTH)** secretion, which leads to **hypercalcemia (increased calcium levels)**, not decreased calcium [1]. - PTH's main actions are to raise serum calcium by increasing **bone resorption**, **renal calcium reabsorption**, and **calcitriol synthesis** [2]. *Nephrolithiasis* - **Hypercalcemia** from primary hyperparathyroidism leads to increased calcium excretion in the urine, increasing the risk of **calcium oxalate stones** (nephrolithiasis) [3]. *Increased alkaline phosphatase* - PTH stimulates osteoclastic activity, leading to **increased bone turnover** and release of enzymes like **alkaline phosphatase**, particularly in cases with significant bone involvement. - Alkaline phosphatase levels may also be elevated due to **osteitis fibrosa cystica**, a severe form of bone disease associated with primary hyperparathyroidism. *Loss of lamina dura* - Chronic hyperparathyroidism can cause characteristic changes in bone, including the **resorption of the lamina dura** around the teeth, which is visible on dental radiographs. - This is a direct consequence of PTH-mediated **osteoclastic activity** in areas of high bone turnover.
Question 4: Primary Hyperparathyroidism is associated with -
- A. Increased serum PTH and Hypercalcemia (Correct Answer)
- B. Decreased serum PTH and Hyporcalcemia
- C. Decreased serum PTH and Hypercalcemia
- D. Increased serum PTH and Hyporcalcemia
Explanation: ***Increased serum PTH and Hypercalcemia*** - **Primary hyperparathyroidism** results from an autonomous overproduction of **parathyroid hormone (PTH)**, usually by an adenoma or hyperplasia [1]. - This excess PTH leads to increased calcium reabsorption from bones and kidneys, causing **hypercalcemia** [2][4]. *Decreased serum PTH and Hyporcalcemia* - This combination is characteristic of **hypoparathyroidism**, where insufficient PTH production leads to low calcium levels [3]. - Primary hyperparathyroidism, by definition, involves *increased* PTH [4]. *Decreased serum PTH and Hypercalcemia* - This might be seen in cases of **non-PTH-mediated hypercalcemia**, such as malignancy, where high calcium levels suppress normal PTH secretion [4]. - However, in primary hyperparathyroidism, PTH would be **elevated** [1]. *Increased serum PTH and Hyporcalcemia* - This scenario typically points to **secondary hyperparathyroidism**, where the parathyroid glands are overactive in response to chronic low calcium levels (e.g., due to **chronic kidney disease** or **Vitamin D deficiency**) [1][3]. - In primary hyperparathyroidism, the elevated PTH directly *causes* hypercalcemia [4].
Question 5: Which hormone increases with age?
- A. GH
- B. Prolactin
- C. Parathormone (Correct Answer)
- D. Insulin
Explanation: ***Parathormone*** - **Parathormone (PTH)** levels in the blood tend to increase with age, often due to a decline in renal function and reduced vitamin D synthesis, leading to compensatory hyperparathyroidism. - This age-related increase in PTH can contribute to **bone demineralization** and an increased risk of osteoporosis. *GH* - **Growth hormone (GH)** levels generally **decrease with age**, leading to a condition known as somatopause. - Reduced GH contributes to changes in body composition, such as increased adiposity and decreased lean muscle mass, as well as reduced bone density. *Prolactin* - **Prolactin** levels typically remain relatively stable or may slightly decrease with age in men, while in women they can fluctuate due to hormonal changes like menopause but do not show a consistent increase with age. - High prolactin levels are often associated with specific pathological conditions like **prolactinomas** rather than normal aging. *Insulin* - While **insulin resistance** often increases with age, leading to higher fasting insulin levels in some individuals, the overall picture of insulin secretion can be complex and is often influenced by factors such as diet, exercise, and genetics rather than solely age. - A *decline in pancreatic beta-cell function* with age can also lead to impaired insulin secretion in some elderly individuals, complicating the simple relationship between age and insulin levels.
Question 6: All the following are seen in Hyperparathyroidism except:
- A. Pepper - pot skull
- B. Loss of lamina dura
- C. Calvarial thickening (Correct Answer)
- D. Subperiosteal erosion of bone
Explanation: ***Calvarial thickening*** - **Calvarial thickening** is typically associated with conditions like **Paget's disease** of bone or certain anemias, which increase bone deposition, whereas hyperparathyroidism leads to bone resorption. - In hyperparathyroidism, the primary skeletal manifestation is **osteoclastic bone resorption**, leading to thinning of cortical bone and loss of bone density, not thickening. *Pepper-pot skull* - This describes the radiographic appearance of the skull due to **resorption of trabecular bone** and formation of numerous small lucencies, giving it a "pepper-pot" or "salt-and-pepper" appearance. - It's a classic sign of **hyperparathyroidism**, indicating diffuse bone demineralization in the skull. *Loss of lamina dura* - The **lamina dura** is the dense bone lining the tooth socket, which appears as a radiopaque line around the tooth root on radiographs. - Its **loss or absence** is a characteristic sign of hyperparathyroidism due to generalized bone demineralization, as it is one of the first cortical bone structures to undergo resorption. *Subperiosteal erosion of bone* - This is considered the **pathognomonic radiographic sign** of hyperparathyroidism, particularly seen in the phalanges of the hand. - It results from excessive **osteoclastic activity** leading to resorption of bone directly beneath the periosteum.
Question 7: A 45-year-old man presents with back pain and facial pain. Physical examination reveals coarse facial features and kyphosis. Laboratory examination shows elevated alkaline phosphatase. Radiographic studies demonstrate skull thickening with narrowing of foramina, and bowing of the femur and tibia. Bone biopsy reveals a mosaic pattern of bone spicules with prominent osteoid seams. Which of the following neoplasms occurs with increased frequency in patients with this disorder?
- A. Astrocytoma
- B. Hodgkin's lymphoma
- C. Meningioma
- D. Osteosarcoma (Correct Answer)
Explanation: ### Explanation **Diagnosis: Paget’s Disease of Bone (Osteitis Deformans)** The clinical presentation of coarse facial features (leontiasis ossea), kyphosis, and bowing of long bones, combined with isolated elevation of **Alkaline Phosphatase (ALP)**, strongly suggests Paget’s disease. The pathognomonic histological finding is the **"Mosaic pattern"** (jigsaw-puzzle appearance) of bone, caused by prominent cement lines reflecting haphazard bone remodeling. #### Why Osteosarcoma is the Correct Answer: The most dreaded complication of long-standing Paget’s disease (especially polyostotic forms) is the development of a secondary malignancy. **Osteosarcoma** occurs in approximately 1% of patients with Paget’s disease. In an elderly patient, the sudden onset of new pain, swelling, or a pathological fracture in a Pagetic bone should immediately raise suspicion for **Pagetoid Sarcoma** (Osteosarcoma). #### Why Other Options are Incorrect: * **A. Astrocytoma & C. Meningioma:** While Paget’s disease causes skull thickening and narrowing of cranial foramina (leading to hearing loss or cranial nerve palsies), it does not predispose patients to primary brain or meningeal tumors. * **B. Hodgkin’s Lymphoma:** There is no established pathophysiological link between the disordered bone remodeling of Paget’s disease and the development of lymphomas. #### NEET-PG High-Yield Pearls: * **Stages of Paget’s:** 1. Osteolytic (Osteoclast-mediated) → 2. Mixed → 3. Osteosclerotic (Burned-out phase). * **Markers:** Elevated Serum ALP and Urinary Hydroxyproline; **Normal** Serum Calcium and Phosphate. * **Radiology:** "Cotton wool" appearance of the skull, "Picture frame" vertebrae, and "Blade of grass" (V-shaped) lytic lesions in long bones. * **Treatment of Choice:** Bisphosphonates (Zoledronic acid) to inhibit osteoclast activity. * **Common Complication:** High-output heart failure (due to extensive arteriovenous shunts in hypervascular bone).
Question 8: Splaying and cupping of the metaphysis is seen in which of the following conditions?
- A. Rickets (Correct Answer)
- B. Scurvy
- C. Paget's disease
- D. Lead poisoning
Explanation: **Explanation:** **Rickets** is the correct answer because it is characterized by a failure of mineralization of the osteoid at the growth plate. In Rickets, the zone of provisional calcification fails to form, leading to an accumulation of unmineralized hypertrophic chondrocytes. This causes the metaphysis to become soft, weak, and bulky. Under the stress of weight-bearing or muscle pull, the softened metaphysis expands laterally (**Splaying**) and becomes concave or hollowed out (**Cupping**). Additionally, the margins appear irregular and fuzzy (**Fraying**). **Why other options are incorrect:** * **Scurvy:** Caused by Vitamin C deficiency, it affects collagen synthesis. Radiographic hallmarks include the *White line of Frankel* (dense zone of provisional calcification), *Wimberger’s ring* (epiphyseal lucency), and *Pelkan spurs*, rather than cupping. * **Paget’s Disease:** A disorder of bone remodeling characterized by excessive resorption and disorganized formation. Key findings include cortical thickening, coarsened trabeculae, and "Picture frame" vertebrae. * **Lead Poisoning:** Characterized by "Lead lines," which are dense transverse radiopaque bands at the metaphysis due to impaired resorptive activity. **High-Yield Clinical Pearls for NEET-PG:** * **Earliest sign of Rickets:** Craniotabes (softening of skull bones). * **Earliest radiological sign of Rickets:** Rarefaction (fading) of the zone of provisional calcification. * **Rachitic Rosary:** Palpable/visible enlargement of costochondral junctions (rounded in Rickets, angular/sharp in Scurvy—known as Scorbutic Rosary). * **Healing sign:** The reappearance of the zone of provisional calcification is the first sign of radiological healing.
Question 9: Bone density is decreased in which of the following conditions?
- A. Osteoporosis (Correct Answer)
- B. Avascular necrosis of bone
- C. Osteopetrosis
- D. Fracture and collapse of cancellous bone
Explanation: **Explanation:** **1. Why Osteoporosis is the Correct Answer:** Osteoporosis is defined as a systemic skeletal disorder characterized by **low bone mass** and micro-architectural deterioration of bone tissue. In this condition, there is a proportional decrease in both the bone mineral (calcium/phosphate) and the bone matrix (collagen). Because the total amount of bone tissue per unit volume is reduced, the **bone mineral density (BMD)** is significantly decreased, leading to increased bone fragility and risk of fractures. **2. Why the Other Options are Incorrect:** * **Avascular Necrosis (AVN):** In the early stages, the bone density may appear normal. However, as the bone dies and attempts to repair (creeping substitution), it often appears **more dense (sclerotic)** on X-ray compared to surrounding osteoporotic bone. * **Osteopetrosis:** Also known as "Marble Bone Disease," this is a genetic disorder where osteoclast function is defective. This leads to a failure of bone resorption, resulting in **increased bone density** (though the bone is paradoxically brittle). * **Fracture and Collapse of Cancellous Bone:** When bone collapses (as seen in vertebral compression fractures), the trabeculae are crushed together. This compaction leads to a localized **increase in radiodensity** on imaging. **High-Yield Clinical Pearls for NEET-PG:** * **Gold Standard for Diagnosis:** DEXA Scan (Dual-Energy X-ray Absorptiometry). * **WHO Criteria:** Osteoporosis is defined as a **T-score ≤ -2.5**. * **Biochemical Profile:** In primary osteoporosis, Serum Calcium, Phosphate, and Alkaline Phosphatase (ALP) levels are typically **Normal**. * **Most Common Site of Fracture:** Vertebral body (compression fracture), followed by the neck of the femur and Colles' fracture.
Question 10: A 40-year-old female presents with urine darkening on standing, joint pain and stiffness, and pigment deposition in joints. What is the probable diagnosis?
- A. Phenylketonuria
- B. Tyrosinemia
- C. Alkaptonuria (Correct Answer)
- D. Tyrosinemia
Explanation: **Explanation:** The clinical presentation of **urine darkening on standing**, joint stiffness, and pigment deposition (ochronosis) is pathognomonic for **Alkaptonuria**. **1. Why Alkaptonuria is Correct:** Alkaptonuria is an autosomal recessive disorder caused by a deficiency of the enzyme **Homogentisate 1,2-dioxygenase**. This leads to the accumulation of **Homogentisic Acid (HGA)**. * **Urine Findings:** When urine is exposed to air (standing), HGA oxidizes into a melanin-like polymer, turning the urine black. * **Ochronosis:** HGA binds to connective tissues (cartilage, sclera, ears), causing bluish-black pigmentation. * **Arthropathy:** Long-term deposition in large joints (spine, hips, knees) leads to degenerative "Ochronotic arthritis," typically manifesting in the 4th decade of life. **2. Why Other Options are Incorrect:** * **Phenylketonuria (PKU):** Caused by Phenylalanine Hydroxylase deficiency. It presents with intellectual disability, "mousy" body odor, and hypopigmentation, not joint pigment deposition. * **Tyrosinemia:** Involves defects in the tyrosine catabolic pathway (e.g., Fumarylacetoacetate hydrolase). It primarily presents with liver failure, renal rickets (Fanconi syndrome), and a "cabbage-like" odor, but not black urine or ochronosis. **3. NEET-PG High-Yield Pearls:** * **Radiology:** Characterized by **intervertebral disc calcification** and narrowing at multiple levels (bamboo spine appearance, but unlike Ankylosing Spondylitis, it spares the sacroiliac joints). * **Diagnosis:** Confirmed by detecting Homogentisic acid in urine using **Gas Chromatography-Mass Spectrometry (GC-MS)**. * **Screening:** Benedict’s test is positive (reducing sugar), and Ferric Chloride test gives a transient deep blue/green color.
Want unlimited practice?
Get full access to all questions, explanations, and performance tracking.
Start For Free