INI-CET 2024 - Internal Medicine Practice Questions

Q: A patient presents with fever and retro-orbital pain. Which investigation should be conducted next for confirmation of dengue fever?

NS1 antigen test. ***NS1 antigen test*** - The **NS1 antigen test** is highly sensitive and specific for dengue in the **early stages** of infection (typically 0-7 days after symptom onset), which is when a patient with fever and retro-orbital pain would likely present. - It detects a non-structural protein of the dengue virus, indicating **active viral replication**. *Viral culture* - **Viral culture** for dengue is time-consuming and technically demanding, making it impractical for rapid diagnosis in clinical settings, especially when an urgent confirmation is needed for patient management. - It is primarily used for research purposes rather than routine clinical diagnosis [2]. *IgM ELISA* - **IgM ELISA** detects antibodies produced in response to dengue infection, which typically become detectable **5-7 days after symptom onset**. - While useful for confirming dengue in later stages of illness, it may yield a **false negative** result if performed too early in the course of the disease [2]. *PCR* - **PCR (Polymerase Chain Reaction)** detects dengue viral RNA and is highly sensitive and specific in the **early acute phase** of infection (first 5 days) [1]. - However, it is generally more expensive, requires specialized laboratory equipment, and has a longer turnaround time compared to the NS1 antigen test, making NS1 a more accessible initial diagnostic choice.

Q: Which of the following statements about obstructive sleep apnea is false?

Contraction of pharyngeal muscles can worsen obstruction. ***Contraction of pharyngeal muscles can worsen obstruction*** - In **obstructive sleep apnea (OSA)**, the pharyngeal muscles are normally responsible for maintaining airway patency [1]. - A *contraction* of these muscles would *open* the airway, whereas *relaxation* or *loss of tone* leads to collapse and obstruction. *Apnea is associated with high respiratory effort* - During an **apneic episode** in OSA, the airway is *obstructed*, leading to continued but **unsuccessful inspiratory efforts** against a closed airway. - This results in a significant increase in **respiratory effort** as the diaphragm and accessory muscles try to overcome the obstruction. *Apnea is associated with fall in SpO2* - The cessation of airflow during **apnea** prevents **gas exchange**, leading to a progressive decrease in **oxygen saturation (SpO2)**. - This **hypoxia** is a hallmark physiological consequence of apneic events and often triggers arousal from sleep [2]. *Apnea is associated with sudden awakening* - The combination of **hypoxia** and **hypercapnia** (increased CO2), along with the increased respiratory effort, stimulates the central nervous system [2]. - This stimulation causes a **brief arousal or awakening** from sleep, often accompanied by gasping or snorting, to re-establish airway patency.

Q: Which of the following is typically not associated with upper motor neuron (UMN) lesions?

Atrophy. ***Atrophy*** - **Severe atrophy** (significant muscle wasting) is a hallmark of **lower motor neuron (LMN) lesions**, where the direct innervation to the muscle is interrupted, leading to denervation and subsequent muscle mass loss [1]. - While some disuse atrophy can occur with UMN lesions due to **immobility**, it is typically not as pronounced or rapid as that seen with LMN lesions [1]. *DTR increased* - **Increased deep tendon reflexes (DTRs)**, also known as hyperreflexia, are a classic sign of **upper motor neuron (UMN) lesions** due to the loss of inhibitory control from higher centers on spinal reflex arcs [1]. - The stretch reflex arc becomes more excitable without descending modulation, leading to exaggerated responses. *Spasticity* - **Spasticity** is characterized by a **velocity-dependent increase in muscle tone** with increased resistance to passive stretch, often accompanied by hyperreflexia [1]. - This is a cardinal sign of **upper motor neuron (UMN) lesions**, resulting from the disinhibition of spinal reflex mechanisms. *Rigidity* - **Rigidity** is a form of hypertonia characterized by a **constant resistance to passive movement** throughout the entire range of motion, independent of the speed of movement [2]. - While it can be seen in some UMN conditions involving the basal ganglia (such as Parkinson's disease), it is **not a typical or direct consequence of UMN tract lesions** in the way spasticity is [2],[3].

Q: A male with hyperpigmentation tanner stage 5 presents with hypertension & precocious puberty. The causative defect is:

11 beta hydroxylase deficiency. ***11 beta hydroxylase deficiency*** - This deficiency leads to an accumulation of **11-deoxycortisol** and **deoxycorticosterone (DOC)**, a potent mineralocorticoid [1]. - **DOC excess** causes **hypertension** and **hypokalemia**, while the shunting of precursors to the androgen pathway results in **precocious puberty** in males and virilization in females, along with **hyperpigmentation** due to increased ACTH [1]. *17 alpha hydroxylase deficiency* - This deficiency impairs the synthesis of **cortisol** and **sex steroids**, leading to an accumulation of **mineralocorticoid precursors (DOC and corticosterone)**. - Patients typically present with **hypertension**, **hypokalemia**, and **absent or rudimentary secondary sexual characteristics** (delayed puberty/sexual infantilism) due to the lack of androgens/estrogens, not precocious puberty. *17 beta hydroxylase deficiency* - This enzyme is crucial for the final step in sex steroid synthesis (e.g., testosterone from androstenedione). - A deficiency would lead to **impaired sexual development** and **ambiguous genitalia or undervirilization** in males, along with delayed puberty, completely contradictory to precocious puberty. *21 beta hydroxylase deficiency* - This is the **most common cause of congenital adrenal hyperplasia (CAH)**, leading to a profound deficiency in cortisol and aldosterone, and an excess in androgens [1]. - Patients typically present with **salt-wasting crises** (due to aldosterone deficiency) or **virilization** (due to androgen excess), but usually **hypotension** (due to salt wasting) or normal blood pressure, not hypertension alongside precocious puberty in this specific manner [1].

Q: Which of the following is the MOST common complication associated with GERD?

Esophagitis. ***Esophagitis*** - **Reflux of gastric acid** into the esophagus directly irritates the esophageal lining, leading to inflammation and cellular damage, commonly presenting as esophagitis [1]. - This recurrent irritation causes histological changes such as **basal cell hyperplasia** and **elongation of papillae**, which are hallmarks of reflux-induced injury [1]. *Chronic cough* - While chronic cough can be a symptom of GERD, it is considered an **extraesophageal manifestation** rather than a direct complication of esophageal mucosal damage. - Its prevalence is lower than esophagitis among GERD complications and it's less direct consequence of acid exposure to the esophagus itself. *Dental erosion* - **Acid reflux** can lead to dental erosion due to the direct contact of acidic gastric contents with tooth enamel. - However, this is less common than esophagitis, which is a direct and frequent consequence of **mucosal acid exposure** within the esophagus [1].

Q: Most reliable indicator of some dehydration?

Thirst. Thirst - **Thirst** is a physiological response to even mild dehydration and is often the **earliest and most reliable indicator** that the body needs fluids [1], [2]. - It reflects an increase in **plasma osmolality**, signaling the brain to initiate fluid-seeking behaviors [1], [2]. *Lethargy* - **Lethargy** indicates more severe dehydration or other underlying conditions, making it a less specific and sensitive early indicator. - It suggests significant neurological impairment due to fluid and electrolyte imbalances, rather than just some dehydration. *Delayed skin pinch* - A **delayed skin pinch** (decreased skin turgor) is a sign of *significant* dehydration, indicating a substantial loss of interstitial fluid. - This sign is often less reliable in infants and the elderly due to differences in skin elasticity. *Sunken eyes* - **Sunken eyes** are a sign of more **moderate to severe dehydration**, reflecting significant fluid volume depletion, especially in infants. - It is not an early or subtle indicator of "some dehydration" but rather a late manifestation [3].

Q: Which of the following disorders presents with repeated catalase positive infections?

CGD. ***CGD*** - Chronic Granulomatous Disease (CGD) is characterized by a defect in **NADPH oxidase**, preventing phagocytes from producing a **respiratory burst** to kill certain bacteria and fungi. - Patients with CGD are particularly susceptible to infections by **catalase-positive organisms** because these organisms degrade hydrogen peroxide, which CGD phagocytes rely on for killing. *Chediak higashi syndrome* - This syndrome involves defective lysosomal trafficking, leading to impaired neutrophil chemotaxis and degranulation, resulting in recurrent infections, but not specifically to **catalase-positive organisms**. - Other features include **partial albinism**, peripheral neuropathy, and normal respiratory burst. *SCID* - Severe Combined Immunodeficiency (SCID) involves a profound defect in both **T-cell and B-cell immunity**, leading to severe and recurrent infections by a wide range of pathogens, not limited to catalase-positive ones [1]. - Patients typically present in infancy with **failure to thrive**, opportunistic infections, and lack of lymphoid tissue [1]. *X linked hypogammaglobulinemia* - Also known as **Bruton's agammaglobulinemia**, this disorder involves a defect in B-cell maturation, leading to the absence of antibodies and recurrent bacterial infections [1]. - The infections are typically with **encapsulated bacteria** and are not specifically linked to catalase-positive organisms [1].

Q: Least common cause for bilateral pedal edema

Chronic vascular insufficiency. ***Chronic vascular insufficiency*** - While chronic venous insufficiency is a common cause of bilateral pedal edema, **arterial insufficiency** (a type of chronic vascular insufficiency) is a much less common cause of pure edema and is more often associated with **ischemic pain**, **ulcers**, and **skin atrophy** [1]. - **Arterial insufficiency** primarily causes limb ischemia rather than significant edema, differentiating it from situations where fluid retention is the primary issue [2]. *CKD* - **Chronic kidney disease (CKD)** leads to impaired fluid and sodium excretion, causing generalized fluid overload. - This fluid overload commonly manifests as **bilateral pedal edema** due to gravity-dependent fluid accumulation. *CLD* - **Chronic liver disease (CLD)**, particularly cirrhosis, results in **portal hypertension** and decreased hepatic synthesis of **albumin**. - This leads to reduced oncotic pressure and increased hydrostatic pressure, driving fluid into the extravascular space, often causing **ascites** and **bilateral pedal edema**. *HF with reduced ejection fraction* - **Heart failure with reduced ejection fraction (HFrEF)** impairs the heart's ability to pump blood effectively, leading to fluid backup in the venous system [2]. - This increased hydrostatic pressure in the peripheral capillaries directly causes **bilateral pedal edema** as fluid extravasates into the interstitial space [2].

Q: All of the following regarding ankylosing spondylitis are true except:

Non-erosive arthritis. ***Non-erosive arthritis*** - Ankylosing spondylitis is characterized by **erosive changes**, particularly at the discovertebral and sacroiliac joints, which can lead to **syndesmophyte formation** and eventual *ankylosis* (fusion) of the spine [1]. - The disease involves inflammation and subsequent **ossification of ligaments**, leading to structural damage rather than being purely non-erosive [1]. *HLA B27 is positive in >90%* - A strong association with **HLA-B27** is a hallmark of ankylosing spondylitis, with over 90% of Caucasian patients testing positive, making it a key diagnostic marker [1]. - While not universally present, its high prevalence further supports this statement as being true [1]. *More common in males than females* - Ankylosing spondylitis typically has a male-to-female predominance, with males generally experiencing **more severe disease progression** and spinal involvement. - While the diagnostic criteria have evolved to recognize a more equitable distribution, the classic presentation often highlights male prevalence. *Typically occurs in late teens to early adulthood (peak onset 20s-30s), but can present after 40 in rare cases* - The onset of ankylosing spondylitis symptoms most commonly occurs in **young adults**, typically between the ages of 20 and 40 [1]. - While less common, a small percentage of patients may experience symptom onset later in life, though this is less typical of the disease's natural history.

Q: A 50-year-old male with a history of chronic alcoholism presents with altered sensorium and signs of portal hypertension. What is the most appropriate initial management step?

Administer lactulose. ***Administer lactulose*** - The patient's presentation with altered sensorium and chronic alcoholism, coupled with signs of portal hypertension, strongly suggests **hepatic encephalopathy**. [1] - **Lactulose** is the most appropriate initial management step because it helps to reduce ammonia absorption from the gut by acidifying the colon and acting as an osmotic laxative, thereby improving neurological function. [1] *Perform upper gastrointestinal endoscopy (UGIE)* - While **portal hypertension** can lead to varices and bleeding, an UGIE is an invasive procedure and not the immediate priority for a patient presenting with altered sensorium due to suspected hepatic encephalopathy. - UGIE would be indicated if there were active **gastrointestinal bleeding** (e.g., hematemesis, melena) or hemodynamic instability, which are not explicitly mentioned as the primary concern. *Administer chlordiazepoxide* - **Chlordiazepoxide** is a benzodiazepine used to treat **alcohol withdrawal syndrome** (delirium tremens), which can also cause altered mental status. - However, given the signs of portal hypertension, **hepatic encephalopathy** is a more likely cause of altered sensorium, and benzodiazepines can worsen it by precipifying sedation. *Administer thiamine* - **Thiamine** administration is crucial in chronic alcoholics to prevent and treat **Wernicke-Korsakoff syndrome**, which can cause altered mental status, ophthalmoplegia, and ataxia. [2] - While important in all chronic alcoholics, addressing the potentially life-threatening ammonia toxicity in **hepatic encephalopathy** with lactulose takes precedence in the immediate management of altered sensorium.

Question 1

A patient presents with fever and retro-orbital pain. Which investigation should be conducted next for confirmation of dengue fever?

Accepted Answer

NS1 antigen test

Answer

Viral culture

Answer

IgM ELISA

Answer

PCR

Question 2

Which of the following statements about obstructive sleep apnea is false?

Accepted Answer

Contraction of pharyngeal muscles can worsen obstruction

Answer

Apnea is associated with high respiratory effort

Answer

Apnea is associated with fall in SpO2

Answer

Apnea is associated with sudden awakening

Question 3

Which of the following is typically not associated with upper motor neuron (UMN) lesions?

Accepted Answer

Atrophy

Answer

DTR increased

Answer

Spasticity

Answer

Rigidity

Question 4

A male with hyperpigmentation tanner stage 5 presents with hypertension & precocious puberty. The causative defect is:

Accepted Answer

11 beta hydroxylase deficiency

Answer

17 alpha hydroxylase deficiency

Answer

17 beta hydroxylase deficiency

Answer

21 beta hydroxylase deficiency

Question 5

Which of the following is the MOST common complication associated with GERD?

Accepted Answer

Esophagitis

Answer

Chronic cough

Answer

Dental erosion

Answer

None of the options

Question 6

Most reliable indicator of some dehydration?

Accepted Answer

Thirst

Answer

Lethargy

Answer

Delayed skin pinch

Answer

Sunken eyes

Question 7

Which of the following disorders presents with repeated catalase positive infections?

Accepted Answer

CGD

Answer

Chediak higashi syndrome

Answer

SCID

Answer

X linked hypogammaglobulinemia

Question 8

Least common cause for bilateral pedal edema

Accepted Answer

Chronic vascular insufficiency

Answer

CKD

Answer

CLD

Answer

HF with reduced ejection fraction

Question 9

All of the following regarding ankylosing spondylitis are true except:

Accepted Answer

Non-erosive arthritis

Answer

HLA B27 is positive in >90%

Answer

More common in males than females

Answer

Typically occurs in late teens to early adulthood (peak onset 20s-30s), but can present after 40 in rare cases

Question 10

A 50-year-old male with a history of chronic alcoholism presents with altered sensorium and signs of portal hypertension. What is the most appropriate initial management step?

Accepted Answer

Administer lactulose

Answer

Perform upper gastrointestinal endoscopy (UGIE)

Answer

Administer chlordiazepoxide

Answer

Administer thiamine

INI-CET 2024 — Internal Medicine