Down-beat nystagmus is seen in lesion of ?
Down beat nystagmus is seen in?
What condition is associated with copper deposition in the cornea?
What is Reifenstein syndrome?
Which of the following is not an absolute indication for hemodialysis?
Which of the following is NOT a feature of scleroderma?
A 40-year-old male patient presents to the Emergency department with central chest pain for 2 hours. The ECG shows ST segment depression and cardiac troponins are elevated. The patient has a positive history of previous PCI 3 months back. He is administered Aspirin, Clopidogrel, Nitrates, and LMWH in the Emergency Department and shifted to the coronary care unit. What is the best recommended course of further action?
What is the best immediate management strategy for a patient experiencing respiratory alkalosis due to anxiety-induced hyperventilation?
Adrenal reserve is best tested by means of infusion with
What is the recommended time frame for completing a blood transfusion after initiation?
NEET-PG 2013 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 81: Down-beat nystagmus is seen in lesion of ?
- A. Cerebellum (Correct Answer)
- B. Basal ganglia
- C. Hippocampus
- D. Brainstem
Explanation: ***Cerebellum*** * **Down-beat nystagmus (DBN)** is most commonly associated with lesions in the **craniocervical junction** and **posterior fossa**, particularly affecting the **flocculonodular lobe** of the cerebellum. * The cerebellum plays a crucial role in maintaining **gaze stability** and coordinating eye movements; damage to specific cerebellar pathways can disrupt the vestibulo-ocular reflex, leading to DBN [1]. *Brainstem* * While the **brainstem** contains critical circuits for eye movements, lesions here typically result in other forms of nystagmus, such as **up-beat nystagmus** or **gaze-evoked nystagmus**, depending on the specific structures involved [1]. * Damage to brainstem nuclei or pathways controlling vertical gaze is usually indicated by different patterns of oculomotor dysfunction. *Basal ganglia* * Lesions in the **basal ganglia** are primarily associated with **movement disorders** like Parkinson's disease or Huntington's disease. * They do not typically cause primary nystagmus; any ocular abnormalities would generally be secondary to global motor control issues rather than direct involvement in oculomotor pathways. *Hippocampus* * The **hippocampus** is a key structure involved in **memory formation** and spatial navigation. * Lesions in the hippocampus cause **amnesia** and navigational deficits, but they are not directly involved in eye movement control or the generation of nystagmus.
Question 82: Down beat nystagmus is seen in?
- A. Brain stem lesions
- B. Pontine hemorrhage and other conditions
- C. Labyrinthine damage and other conditions
- D. Arnold Chiari malformation and other conditions (Correct Answer)
Explanation: ***Arnold Chiari malformation and other conditions*** - Downbeat nystagmus is a characteristic finding in Arnold-Chiari malformations, especially **Chiari type 1**, due to compression of cerebellar structures. - Other conditions associated with downbeat nystagmus include **medullary lesions**, **magnesium deficiency**, and **lithium toxicity** [1]. *Brain stem lesions* - While brainstem lesions can cause various nystagmus types, **pure downbeat nystagmus** is less commonly the primary or most specific finding compared to cerebellar involvement [1]. - **Upbeat nystagmus** and other complex nystagmus patterns are more often associated with brainstem lesions like those in the tegmentum. *Pontine hemorrhage and other conditions* - Pontine hemorrhages are more commonly associated with **ocular bobbing**, **blink reflex abnormalities**, or **horizontal gaze palsies**, rather than downbeat nystagmus. - A pontine hemorrhage would typically present with more severe neurological deficits such as **coma** or **quadriparesis**, which are not directly associated with isolated nystagmus. *Labyrinthine damage and other conditions* - **Peripheral vestibular abnormalities** from labyrinthine damage typically cause **horizontal or torsional nystagmus**, often suppressed by visual fixation. - Downbeat nystagmus is a **central vestibular sign**, indicating a problem with central vestibular processing rather than the peripheral labyrinth [1].
Question 83: What condition is associated with copper deposition in the cornea?
- A. Keratoglobus
- B. Keratoconus
- C. Siderosis
- D. Wilson's disease (Correct Answer)
Explanation: ***Wilson's disease*** - Wilson's disease is a genetic disorder of **copper metabolism** leading to excess copper accumulation in various tissues, including the cornea [1]. - This copper deposition in the posterior Descemet's membrane of the cornea forms a distinctive golden-brown or greenish-brown ring known as the **Kayser-Fleischer ring**. *Keratoconus* - This condition is characterized by progressive thinning and steepening of the cornea, causing it to bulge into a **cone-like shape**. - It primarily affects vision due to irregular astigmatism and does not involve copper deposition. *Keratoglobus* - Keratoglobus is a rare corneal ectatic disorder where the entire cornea is thinned and bulges forward, giving it a **globe-like appearance**. - It is congenital and typically runs in families, and it is not associated with copper deposition. *Siderosis* - Siderosis refers to the deposition of **iron** in various tissues, often due to chronic hemorrhage or metallic foreign bodies. - In the eye, it can occur after intraocular iron foreign bodies, leading to retinal degeneration and other ocular complications, but it does not involve copper.
Question 84: What is Reifenstein syndrome?
- A. Partial androgen insensitivity syndrome due to receptor mutation. (Correct Answer)
- B. Complete androgen insensitivity syndrome with female external genitalia
- C. 5-alpha reductase deficiency causing ambiguous genitalia
- D. Gonadal dysgenesis with streak gonads
Explanation: Partial androgen insensitivity syndrome due to receptor mutation. - **Reifenstein syndrome** is a form of **partial androgen insensitivity syndrome (PAIS)**, characterized by varying degrees of undervirilization in 46,XY individuals. [4] - It results from mutations in the **androgen receptor (AR) gene**, leading to impaired androgen signaling. [4] *Complete androgen insensitivity syndrome with female external genitalia* - This describes **complete androgen insensitivity syndrome (CAIS)**, where affected individuals are 46,XY with completely female external genitalia, normal breast development, but no uterus. [4] - Unlike Reifenstein syndrome, there are no signs of virilization. [4] *5-alpha reductase deficiency causing ambiguous genitalia* - **5-alpha reductase deficiency** impedes the conversion of testosterone to the more potent **dihydrotestosterone (DHT)**, which is crucial for external male genital development. - While it causes **ambiguous genitalia**, it's a defect in hormone metabolism, not the androgen receptor itself. *Gonadal dysgenesis with streak gonads* - **Gonadal dysgenesis** refers to conditions where the gonads (testes or ovaries) fail to develop or develop abnormally, often leading to **streak gonads**. [3] - This is a primary gonadal developmental defect, distinct from disorders of androgen action or synthesis. [1], [2]
Question 85: Which of the following is not an absolute indication for hemodialysis?
- A. GI bleeding (Correct Answer)
- B. Convulsions
- C. Pericarditis
- D. Hyperkalemia of 6.5 mEq/L
Explanation: ***GI bleeding*** - While patients on dialysis may experience gastrointestinal bleeding, it is not a direct indication for initiating or continuing **hemodialysis**. - **GI bleeding** in end-stage renal disease (ESRD) patients can be due to various causes and requires specific management of the bleeding itself, not necessarily an alteration in dialysis prescription. *Convulsions* - **Convulsions** in patients with renal failure, especially due to uremia, are a severe manifestation of **uremic encephalopathy**. - This is an absolute indication for **hemodialysis** as it rapidly removes uremic toxins causing central nervous system dysfunction. *Pericarditis* - **Uremic pericarditis**, characterized by inflammation of the pericardium due to accumulation of uremic toxins, is a serious complication of renal failure. - It is an absolute indication for **hemodialysis** to prevent further cardiac complications like cardiac tamponade. *Hyperkalemia of 6.5 mEq/L* - Severe **hyperkalemia** (typically > 6.0-6.5 mEq/L) is a life-threatening electrolyte imbalance that can cause cardiac arrhythmias. - **Hemodialysis** is highly effective in rapidly removing potassium from the body and is an absolute indication, especially if unresponsive to other medical therapies.
Question 86: Which of the following is NOT a feature of scleroderma?
- A. Restrictive cardiomyopathy
- B. Halitosis
- C. Syndactyly (Correct Answer)
- D. Decrease in tone of LES
Explanation: ***Syndactyly*** - **Syndactyly** (fusion of digits) is a congenital anomaly and is **not** a typical feature of scleroderma. - Scleroderma primarily involves **fibrosis** and vascular changes, leading to skin thickening, not digit fusion [1]. *Decrease in tone of LES* - A **decrease in tone of the lower esophageal sphincter (LES)** is a common gastrointestinal manifestation of scleroderma. - This leads to **gastroesophageal reflux disease (GERD)** and related symptoms due to smooth muscle atrophy and fibrosis. *Restrictive cardiomyopathy* - **Restrictive cardiomyopathy** can occur in scleroderma due to **myocardial fibrosis**, leading to impaired diastolic filling. - This is a serious cardiac complication that can cause **heart failure**. *Halitosis* - **Halitosis** (bad breath) can be an indirect manifestation of scleroderma, often associated with severe **GERD**. - Impaired esophageal motility and reflux are common in scleroderma and can contribute to dental problems and **oral dysbiosis**, which can cause halitosis.
Question 87: A 40-year-old male patient presents to the Emergency department with central chest pain for 2 hours. The ECG shows ST segment depression and cardiac troponins are elevated. The patient has a positive history of previous PCI 3 months back. He is administered Aspirin, Clopidogrel, Nitrates, and LMWH in the Emergency Department and shifted to the coronary care unit. What is the best recommended course of further action?
- A. Early Revascularization with PCI (Correct Answer)
- B. Continue conservative management and monitoring of cardiac enzymes and ECG
- C. Continue conservative management and plan for outpatient follow-up
- D. Immediate Revascularization with Coronary Angiography
Explanation: ***Early Revascularization with PCI*** - The patient presents with **NSTEMI** (ST depression, elevated troponins) and is already on antiplatelet and anticoagulant therapy. **Early revascularization** (ideally within 24 hours for high-risk NSTEMI) is indicated to restore blood flow and prevent further myocardial damage [1]. - Given the patient's history of prior **PCI** and the current NSTEMI presentation, this suggests possible **in-stent restenosis** or progression of coronary artery disease, making revascularization crucial. *Continue conservative management and monitoring of cardiac enzymes and ECG* - While initial conservative management with medications is appropriate, simply continuing monitoring without definitive intervention is insufficient for a **high-risk NSTEMI** patient. - The elevated troponins and ST depression indicate ongoing myocardial injury that requires active management beyond just observation [1]. *Continue conservative management and plan for outpatient follow-up* - This approach is entirely inappropriate for a patient presenting with an **acute coronary syndrome (NSTEMI)**. - Outpatient follow-up is for stable conditions, not for an ongoing cardiac event that requires urgent hospital-based intervention. *Immediate Revascularization with Coronary Angiography* - **Immediate revascularization** (within 90 minutes) is primarily indicated for **STEMI** (ST elevation myocardial infarction). - While coronary angiography will precede PCI, the term "immediate" in this context usually refers to the urgency seen in STEMI; NSTEMI typically warrants "early" rather than "immediate" intervention (within 12-24 hours for high-risk patients like this one) [1].
Question 88: What is the best immediate management strategy for a patient experiencing respiratory alkalosis due to anxiety-induced hyperventilation?
- A. Rebreathing in paper bag (Correct Answer)
- B. IPPV
- C. Normal saline
- D. Acetazolamide
Explanation: ***Rebreathing in paper bag*** - This helps to **increase the inspired CO2 concentration**, thereby correcting the hypocapnia (low CO2) caused by hyperventilation. - It's a simple, non-invasive method to raise arterial PCO2 and normalize blood pH in acute respiratory alkalosis. *IPPV* - **Intermittent positive pressure ventilation (IPPV)** would further reduce CO2 by assisting ventilation and is typically used for respiratory *acidosis* or failure [1]. - This intervention would worsen the patient's respiratory alkalosis rather than alleviating it. *Normal saline* - **Normal saline** administration is primarily used for volume expansion or to correct electrolyte imbalances; it does not directly address respiratory alkalosis. - It would not correct the underlying issue of excessive CO2 exhalation. *Acetazolamide* - **Acetazolamide** is a carbonic anhydrase inhibitor that reduces bicarbonate reabsorption and is used to treat metabolic alkalosis or as a diuretic. - It would not be an immediate or appropriate solution for acute respiratory alkalosis and might even worsen the acid-base balance if used improperly.
Question 89: Adrenal reserve is best tested by means of infusion with
- A. ACTH (Correct Answer)
- B. Metyrapone
- C. Corticosteroids
- D. LHRH
Explanation: ACTH - The **ACTH stimulation test**, also known as the **cosyntropin test**, is the most common dynamic test for assessing adrenal reserve. - Exogenous ACTH (cosyntropin) stimulates the adrenal glands to produce cortisol; a subnormal response indicates adrenal insufficiency. *Corticosteroids* - **Corticosteroids** are hormones (like cortisol) produced by the adrenal glands, or synthetic versions used as medications; they do not test adrenal reserve but rather *replace* adrenal function. - Administering corticosteroids would interfere with, rather than assess, the adrenal gland's ability to produce its own hormones. *LHRH* - **Luteinizing hormone-releasing hormone (LHRH)** is used to assess the function of the anterior pituitary gland and gonads, not the adrenal glands. - An LHRH stimulation test evaluates the pituitary's ability to release LH and FSH, which in turn stimulate gonadal hormone production. *Metyrapone* - The **metyrapone test** assesses the integrity of the **hypothalamic-pituitary-adrenal axis** by blocking cortisol synthesis, which should lead to an increase in ACTH and 11-deoxycortisol [1]. - While it evaluates a part of adrenal function, it is primarily used to differentiate between primary and secondary adrenal insufficiency, and not a direct measure of cortisol production capacity in response to stimulation.
Question 90: What is the recommended time frame for completing a blood transfusion after initiation?
- A. 1-4 hours (Correct Answer)
- B. 3-6 hours
- C. 4-8 hours
- D. 8-12 hours
Explanation: ***1-4 hours*** - This timeframe is recommended to **minimize the risk of bacterial growth** in the blood product, as bacteria can multiply quickly at room temperature. - Completing the transfusion within 4 hours also reduces the likelihood of **red blood cell degeneration** and loss of efficacy. *3-6 hours* - This period extends beyond the recommended maximum of 4 hours, increasing the risk of **bacterial proliferation** in the blood product. - Prolonged infusion times can also lead to a **decrease in the viability and function** of transfused cells. *4-8 hours* - Transfusing over 4-8 hours significantly elevates the risk of **bacterial contamination** and potential septic reactions. - The extended duration compromises the **quality and safety** of the blood product. *8-12 hours* - This timeframe is unacceptably long for a blood transfusion, posing a **critical risk of severe bacterial growth** and infection. - Blood products should not be administered beyond 4 hours due to the rapid decline in **cell integrity and increased adverse reaction potential**.