Which of the following conditions is the classic example of acute intravascular hemolysis triggered by oxidative stress?
What is the most common site of gastrointestinal stromal tumors (GISTs)?
Which condition is most commonly associated with systemic amyloidosis?
What is the term for the collapse of a lung?
Serological testing of patient shows HBsAg, IgM anti-HBc and HBeAg positive. The patient has -
HIV post exposure prophylaxis should be started within?
Among the following, most reliable test for screening of diabetes mellitus?
What is the primary electrolyte found in Oral Rehydration Salts (ORS) at a concentration of 75 mEq/L?
Tabes dorsalis is seen in -
Meningitis with rash is seen in -
NEET-PG 2012 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 21: Which of the following conditions is the classic example of acute intravascular hemolysis triggered by oxidative stress?
- A. Hereditary spherocytosis
- B. Sickle cell disease
- C. Acute G6PD deficiency (Correct Answer)
- D. None of the options
Explanation: ***b and c*** - Intravascular hemolysis is commonly associated with both **Acute G6PD deficiency** and **Hereditary spherocytosis**, leading to destruction of red blood cells in the bloodstream [1]. - These conditions are characterized by **high levels of hemoglobinuria** and **low haptoglobin**, indicative of intravascular hemolysis. *Sickle cell ds* - Sickle cell disease primarily causes **extravascular hemolysis** due to splenic sequestration rather than **intravascular** destruction [3]. - The clinical features include **vaso-occlusive crises** and splenic infarction rather than hemolysis within the blood vessels. *Acute G6PD* - While acute G6PD deficiency can lead to hemolysis, it is typically **triggered by oxidative stress** rather than occurring continuously [2]. - The hemolysis in G6PD deficiency occurs more in an **extravascular** manner unless acute stress occurs, which can result in **acute intravascular hemolysis, marked by anemia, hemoglobinemia, and hemoglobinuria** [4]. *Hereditary spherocytosis* - This condition primarily causes **extravascular hemolysis** through the spleen, where abnormal spherocytes are destroyed [1]. - Although it leads to anemia, the hallmark of hereditary spherocytosis is the **spleen's role** in hemocyte destruction rather than intravascular hemolysis.
Question 22: What is the most common site of gastrointestinal stromal tumors (GISTs)?
- A. Ileum
- B. Esophagus
- C. Colon
- D. Stomach (Correct Answer)
Explanation: Stomach - The stomach is the most common site for gastrointestinal stromal tumors (GISTs), accounting for approximately 60-70% of cases. - GISTs in the stomach often present with symptoms like abdominal pain or bleeding and are associated with mutations in the KIT gene. Ileum - Although GISTs can occur in the ileum, they are far less common than those found in the stomach, representing about 10-15% of cases [1]. - GISTs in the ileum tend to present differently, often with intestinal obstruction or pain [1]. Esophagus - Esophageal GISTs are rare and account for only about 5% of GIST cases, making them an uncommon location. - Symptoms are usually related to dysphagia or chest pain, not typical for GISTs arising from more common sites. Colon - Although GISTs can occur in the colon, their frequency is much lower compared to the stomach and represents a small percentage of cases. - Clinical features in colonic GISTs can mimic other colorectal tumors, often causing obstruction or bleeding rather than classic GIST symptoms.
Question 23: Which condition is most commonly associated with systemic amyloidosis?
- A. Chronic Kidney Disease (Correct Answer)
- B. Multiple Myeloma
- C. Rheumatoid Arthritis
- D. Familial Mediterranean Fever
Explanation: Type II DM - Amyloidosis is commonly associated with **chronic diseases** like type II diabetes mellitus due to insulin resistance leading to amyloid deposition [4]. - The presence of **amiloid in the pancreas** often correlates with the complications of this type of diabetes [3]. *Maturity onset DM* - While maturity-onset diabetes can lead to complications, it is often synonymous with **type II DM**, making this distinction inaccurate regarding amyloidosis. - This term is less commonly used and does not emphasize the direct link to amyloidosis seen in type II diabetes. *HTN* - Hypertension itself is not a direct cause of amyloidosis; it typically results from other underlying conditions. - The association of amyloidosis with hypertension is usually **secondary**, not a primary condition leading to amyloid deposits [2]. *Type I DM* - Type I diabetes is primarily **autoimmune**, resulting in insulin-deficient states and does not strongly associate with amyloidosis like type II [1]. - The amyloid deposits seen in type I are much less common compared to type II or associated chronic conditions.
Question 24: What is the term for the collapse of a lung?
- A. Emphysema
- B. Atelectasis (Correct Answer)
- C. Bronchitis
- D. Bronchiectasis
Explanation: ***Atelectasis*** - **Atelectasis** is the technical term for the **collapse of a lung** or a part of a lung, leading to reduced or absent gas exchange. - It can be caused by **obstruction of the airway** (e.g., mucus plug, foreign body) or external compression on the lung [1]. *Emphysema* - **Emphysema** is a chronic lung disease characterized by the **destruction of the alveoli**, leading to permanent enlargement of airspaces [2]. - It results in reduced elastic recoil of the lungs and is a type of **COPD (chronic obstructive pulmonary disease)** [2]. *Bronchiectasis* - **Bronchiectasis** is a chronic condition where the airways (bronchi) become **abnormally widened** and scarred. - This widening leads to a buildup of mucus, making the lungs vulnerable to **recurrent infections**. *Bronchitis* - **Bronchitis** is an inflammation of the lining of the bronchial tubes, which carry air to and from your lungs. - It typically causes a **cough** with mucus production and can be acute or chronic.
Question 25: Serological testing of patient shows HBsAg, IgM anti-HBc and HBeAg positive. The patient has -
- A. Acute hepatitis B with high infectivity (Correct Answer)
- B. Chronic hepatitis with high infectivity
- C. Acute on chronic hepatitis
- D. Chronic hepatitis B with low infectivity (not acute)
Explanation: ***Acute hepatitis B with high infectivity*** - The presence of **HBsAg** (hepatitis B surface antigen) indicates active infection, while **IgM anti-HBc** (IgM antibody to hepatitis B core antigen) is a marker of recent or acute infection [1]. - **HBeAg** (hepatitis B e-antigen) positivity signifies active viral replication and a high likelihood of infectivity [1]. *Chronic hepatitis B with low infectivity (not acute)* - **Chronic hepatitis B** is characterized by the presence of **HBsAg for more than six months**, but **IgM anti-HBc** would typically be negative; instead, **IgG anti-HBc** would be positive [1]. - **Low infectivity** would be indicated by the absence of **HBeAg**, replaced by **anti-HBe** (antibody to HBeAg) [1]. *Chronic hepatitis with high infectivity* - This diagnosis would show positive **HBsAg and HBeAg**, but the absence of **IgM anti-HBc** (presence of **IgG anti-HBc** instead) would distinguish it from acute infection [1]. - The presence of **IgM anti-HBc** is a crucial marker for an acute phase of hepatitis B rather than chronic. *Acute on chronic hepatitis* - This scenario would involve a patient with pre-existing **chronic hepatitis B** (positive HBsAg, IgG anti-HBc) experiencing a new acute flare-up, which could involve a resurgence of **HBeAg** or a new acute viral insult. - While **HBsAg** and **HBeAg** would be positive, the key differentiator would be the presence of both **IgM anti-HBc** (indicating the acute component) and **IgG anti-HBc** (indicating the chronic component), which is not fully described here to confirm acute on chronic.
Question 26: HIV post exposure prophylaxis should be started within?
- A. 1-2 hrs
- B. 14 hrs
- C. 18 hrs
- D. 72 hrs (Correct Answer)
Explanation: ***72 hrs*** - **Post-exposure prophylaxis (PEP)** aims to prevent HIV infection after potential exposure and should ideally be initiated as soon as possible, but no later than **72 hours** after exposure [1]. - Starting PEP within this window significantly increases its effectiveness in preventing HIV seroconversion. *1-2 hrs* - While initiating PEP as soon as possible is crucial, stating it must be within **1-2 hours** can be misleading as the window of effectiveness extends beyond this. - This timeframe might be an ideal, but not the absolute crucial limit for efficacy. *14 hrs* - This timeframe is **too restrictive** for the recommended window for PEP initiation. - Missing the opportunity within **14 hours** does not negate the effectiveness of PEP if started within the broader 72-hour window. *18 hrs* - Similar to **14 hours**, **18 hours** is an unnecessarily strict limit for PEP initiation. - Guidelines universally support starting PEP up to **72 hours** post-exposure for optimal benefit [1].
Question 27: Among the following, most reliable test for screening of diabetes mellitus?
- A. Urine sugar
- B. Random sugar
- C. Fasting sugar (Correct Answer)
- D. Glucose tolerance test
Explanation: ***Fasting sugar*** - A **fasting plasma glucose** (FPG) test is the most common and reliable initial test for screening for **diabetes mellitus** because it measures blood glucose after an overnight fast (typically 8-12 hours), providing a baseline level unaffected by recent food intake [1]. - A fasting glucose level of **≥ 126 mg/dL** (7.0 mmol/L) on two separate occasions is diagnostic of diabetes, making it an excellent screening tool for identifying individuals with impaired glucose metabolism [1]. *Random sugar* - A random plasma glucose test can be used to diagnose diabetes if the level is **≥ 200 mg/dL** (11.1 mmol/L) in a symptomatic individual, but it is less reliable for screening asymptomatic individuals due to its variability depending on recent food intake [1]. - Because it can be measured at any time of day without regard to the last meal, it has a **lower sensitivity** for detecting early stages of diabetes compared to fasting glucose. *Glucose tolerance test* - An **oral glucose tolerance test** (OGTT) is highly sensitive and specific for diagnosing diabetes and impaired glucose tolerance, but it is more cumbersome and time-consuming, involving multiple blood draws over two hours after consuming a sugary drink. - While it is a definitive diagnostic test, its complexity makes it **less practical for routine screening** in large populations compared to simpler tests like fasting plasma glucose. *Urine sugar* - The presence of glucose in urine (glycosuria) indicates that blood glucose levels have exceeded the **renal threshold** (typically around 180 mg/dL), meaning the kidneys are unable to reabsorb all the glucose. - This is a **less sensitive and specific** method for screening, as it only becomes positive once blood glucose is significantly elevated, and it does not detect milder forms of impaired glucose metabolism or early diabetes.
Question 28: What is the primary electrolyte found in Oral Rehydration Salts (ORS) at a concentration of 75 mEq/L?
- A. Sodium (Correct Answer)
- B. Potassium
- C. Glucose
- D. Chloride
Explanation: ***Sodium*** - The primary electrolyte in **Oral Rehydration Salts (ORS)** is **sodium**, which is crucial for replacing losses due to diarrhea and facilitating water absorption in the intestines [1]. - The standard ORS formulation, recommended by the WHO, contains **75 mEq/L of sodium** to effectively rehydrate individuals with acute watery diarrhea [1]. *Potassium* - While **potassium** is an essential electrolyte found in ORS, its concentration is typically lower than sodium, usually around **20 mEq/L**. - Potassium helps replenish intracellular losses and supports normal cellular function, but it is not the primary electrolyte at the 75 mEq/L concentration. *Glucose* - **Glucose** is a crucial component of ORS, but it is a sugar, not an electrolyte. - Its role is to facilitate the co-transport of **sodium and water** across the intestinal wall, enhancing fluid absorption, but it does not contribute to the electrolyte concentration in mEq/L [1]. *Chloride* - **Chloride** is an electrolyte present in ORS, primarily to balance the charge of **sodium** and prevent hyynatremia. - Its concentration is typically around **65 mEq/L**, making it slightly less concentrated than sodium but still vital for maintaining electrolyte balance.
Question 29: Tabes dorsalis is seen in -
- A. Tertiary syphilis (Correct Answer)
- B. Primary syphilis
- C. Latent syphilis
- D. Secondary syphilis
Explanation: ***Tertiary syphilis*** - **Tabes dorsalis** is a neurological manifestation of **tertiary syphilis**, characterized by demyelination and degeneration of the posterior columns of the spinal cord [1]. - This leads to symptoms such as **ataxia**, **loss of proprioception**, **lightning pains**, and **Argyll-Robertson pupils**. *Primary syphilis* - Characterized by the presence of a **chancre**, a painless ulcer, at the site of infection [1]. - This stage typically occurs 3-90 days after exposure and is not associated with neurological complications of tabes dorsalis. *Latent syphilis* - This is a period during which there are **no clinical signs or symptoms** of syphilis, although the infection persists. - It can be early or late, but it is not the stage where overt neurological complications like tabes dorsalis arise [1]. *Secondary syphilis* - This stage typically presents with a **generalized mucocutaneous rash**, **lymphadenopathy**, and **condylomata lata** [1]. - While it can involve various organ systems, it does not typically include the severe neurological degeneration seen in tabes dorsalis.
Question 30: Meningitis with rash is seen in -
- A. Neisseria meningitidis (Correct Answer)
- B. H. influenzae
- C. Strepto. agalactae
- D. Pneumococcus
Explanation: **Neisseria meningitidis** - **Meningococcal meningitis** is classically associated with an acute onset of fever, headache, stiff neck, and a characteristic **petechial or purpuric rash** [1]. - The rash is due to widespread **vasculitis** and disseminated intravascular coagulation (DIC) caused by the bacteria. *H. influenzae* - While *H. influenzae* type b (Hib) was a major cause of bacterial meningitis before vaccination, it typically does not cause a *rash*. - Meningitis caused by *H. influenzae* presents with fever, headache, stiff neck, and altered mental status without dermatological manifestations. *Strepto. agalactiae* - *Streptococcus agalactiae* (Group B Strep) is a common cause of meningitis in **neonates** and infants. - It usually presents with non-specific symptoms like fever, lethargy, and poor feeding, and a rash is not a typical feature of GBS meningitis. *Pneumococcus* - *Streptococcus pneumoniae* (Pneumococcus) is another leading cause of bacterial meningitis in adults and children [1]. - Symptoms include fever, headache, stiff neck, and altered mental status, but a cutaneous rash is not characteristic of pneumococcal meningitis [1].