Diabetic foot is associated with following type of gangrene -
Which type of artery is most commonly involved in PAN?
Which of the following statements about sickle cell disease is true?
Which antibody is primarily associated with warm autoimmune hemolytic anemia (AIHA)?
In which non-neoplastic condition is CEA commonly elevated?
What is the mode of inheritance for the most common form of hypophosphatemic rickets?
What is the immediate emergency treatment for carbon monoxide (CO) poisoning?
Which subtype of Acute Myeloid Leukemia (AML) is associated with the best prognosis?
Which of the following does not predispose to leukemia?
Shrinking Lung Syndrome is seen in:
NEET-PG 2015 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 11: Diabetic foot is associated with following type of gangrene -
- A. Dry gangrene
- B. Wet gangrene (Correct Answer)
- C. Gas gangrene
- D. Fournier's gangrene
Explanation: ***Wet gangrene*** - Diabetic foot commonly leads to **ischemia** and **infection** [1], resulting in wet gangrene characterized by moist, necrotic tissue. - This type of gangrene is associated with **rapid progression** and can result in systemic toxicity, making prompt treatment essential. *Fournier's gangrene* - This type of gangrene specifically affects the **perineal** region and is not directly associated with diabetic foot. - It usually arises from infections related to **perineal trauma** or surgical procedures. *Gas gangrene* - Caused by **Clostridium** species and typically follows a traumatic injury or surgical procedure, not specifically related to diabetes. - Presents with **crepitus** and rapid systemic symptoms, different from the chronic nature of diabetic ulcers. *Dry gangrene* - Associated with **chronic ischemia** and necrosis, it occurs in conditions like peripheral arterial disease, not primarily with infections seen in diabetic foot [1]. - It usually develops gradually without the sudden onset of symptoms characteristic of wet gangrene.
Question 12: Which type of artery is most commonly involved in PAN?
- A. Muscular (Correct Answer)
- B. Capillaries
- C. Elastic
- D. Arterioles
Explanation: ***Muscular*** - **Polyarteritis nodosa (PAN)** predominantly affects **medium to small-sized muscular arteries**, leading to inflammation, necrosis, and microaneurysms [1]. - This involvement often causes **organ ischemia** and symptoms related to the affected organs, such as the kidneys, gastrointestinal tract, and skin [1]. *Elastic* - **Elastic arteries**, such as the aorta and its major branches, are typically spared in PAN due to their larger size and distinct histological structure. - Diseases like **Takayasu arteritis** or **Giant cell arteritis** are more commonly associated with vasculitis affecting large elastic arteries. *Arterioles* - While arterioles can be affected in various forms of vasculitis, they are not the primary target in classic PAN. - Involvement of arterioles is more characteristic of **microscopic polyangiitis** or **Churg-Strauss syndrome** [2]. *Capillaries* - **Capillaries** are the smallest blood vessels, and their involvement is rare in PAN. - Conditions like **Henoch-Schönlein purpura** or some drug-induced vasculitides more typically affect capillaries, often resulting in palpable purpura [2].
Question 13: Which of the following statements about sickle cell disease is true?
- A. Sickling is completely reversible with oxygenation, making it clinically insignificant.
- B. Sickling leads to a significant increase in overall MCHC levels in the blood.
- C. Fetal hemoglobin inhibits sickling. (Correct Answer)
- D. Sickling occurs exclusively in the homozygous state and never in the heterozygous state.
Explanation: ***Sickling is reversible with oxygenation*** - When oxygen tension is restored, hemoglobin S can re-hydrate and revert to its normal shape, reducing sickling. - This reversible process is essential for managing episodes of vaso-occlusive crisis in sickle cell disease. *Fetal hemoglobin facilitates Sickling* - Fetal hemoglobin (HbF) actually inhibits sickling by stabilizing the erythrocyte shape and reducing the proportion of hemoglobin S [1]. - Individuals with higher levels of HbF experience fewer sickling-related complications [1]. *Sickling occurs both in heterozygous and homozygous state* - Sickling primarily occurs in the homozygous state (HbSS); heterozygotes (HbAS) usually do not experience significant sickling effects [1]. - Heterozygous individuals may have a selective advantage against malaria, but they are not prone to sickle cell crises. *Sickling Leads to decreased MCHC* - Sickling does not directly lead to decreased mean corpuscular hemoglobin concentration (MCHC); MCHC is typically normal in sickle cell patients. - In fact, sickle cell disease often results in hemolysis and can lead to increased MCHC in some cases.
Question 14: Which antibody is primarily associated with warm autoimmune hemolytic anemia (AIHA)?
- A. IgE
- B. IgM
- C. IgG (Correct Answer)
- D. IgD
Explanation: ***IgG*** - **Warm autoimmune hemolytic anemia (AIHA)** is primarily associated with **IgG antibodies**, which mediate hemolysis at body temperature [1]. - IgG antibodies typically bind to red blood cells and lead to their destruction by the **reticuloendothelial system** [1]. *IgM* - Often involved in **cold agglutinin disease**, not warm AIHA, as it primarily reacts at lower temperatures [2]. - Usually results in **hemolysis** in peripheral areas, like the extremities, rather than at normal body temperature [2]. *IgD* - Known primarily as a marker on **B cells**, it plays a minimal role in hemolytic anemia and is not involved in antibody-mediated hemolysis. - Lack of significant **serological presence** in autoimmune hemolytic processes makes it an unlikely candidate. *IgE* - Primarily associated with **allergic reactions** and parasitic infections rather than autoimmune hemolytic conditions [2]. - Does not typically participate in **hemolysis** or bind to red blood cells in AIHA.
Question 15: In which non-neoplastic condition is CEA commonly elevated?
- A. Pancreatitis
- B. Inflammatory bowel disease (Correct Answer)
- C. Hemolytic anemia
- D. Liver disease
Explanation: ***Inflammatory bowel disease*** - **Carcinoembryonic antigen (CEA)** levels can be elevated in conditions involving active inflammation and rapid cell turnover within the gastrointestinal tract, such as **inflammatory bowel disease (IBD)** [1]. - While CEA is primarily a tumor marker, its elevation in IBD reflects the extensive mucosal inflammation and repair processes, rather than malignancy. *Hemolytic anemia* - **Hemolytic anemia** involves the destruction of red blood cells and does not typically lead to elevated CEA levels. - Elevated CEA is associated with certain epithelial conditions, not primary hematologic disorders. *Pancreatitis* - While **pancreatitis** can cause elevated levels of other markers like amylase and lipase, it is not consistently associated with elevated CEA. - CEA elevation in pancreatic conditions usually points towards a **pancreatic malignancy**. *Liver disease* - **Liver disease**, particularly severe inflammation or cirrhosis, can sometimes cause a mild elevation in CEA due to impaired clearance or increased production in damaged tissue. - However, levels are typically not as high or consistently elevated as in IBD, and significant elevation often prompts investigation for **primary hepatic or metastatic malignancy**.
Question 16: What is the mode of inheritance for the most common form of hypophosphatemic rickets?
- A. Autosomal Recessive (AR)
- B. Autosomal Dominant (AD)
- C. X-Linked Recessive (XR)
- D. X-Linked Dominant (XD) (Correct Answer)
Explanation: ***X-Linked Dominant (XD)*** - The most common form of hypophosphatemic rickets is **X-linked hypophosphatemic rickets (XLH)**, which is inherited in an X-linked dominant pattern. - This condition is caused by mutations in the **PHEX gene** on the X chromosome, leading to impaired phosphate reabsorption in the kidneys. *Autosomal Recessive (AR)* - While some rare forms of hypophosphatemic rickets exist with **autosomal recessive** inheritance, they are not the most common. - These forms typically involve mutations in genes affecting phosphate transport or vitamin D metabolism, distinct from the primary defect in XLH. *Autosomal Dominant (AD)* - There are also rare **autosomal dominant** forms of hypophosphatemic rickets, such as hereditary hypophosphatemic rickets with hypercalciuria (HHRH) or autosomal dominant hypophosphatemic rickets (ADHR). - However, these are less common than the X-linked dominant form (XLH). *X-Linked Recessive (XR)* - **X-linked recessive** inheritance typically affects males more severely and exclusively, with carrier females usually unaffected or mildly affected. - In X-linked dominant conditions like XLH, both males and females are affected, though females may exhibit variable expressivity.
Question 17: What is the immediate emergency treatment for carbon monoxide (CO) poisoning?
- A. 5% CO2 inhalation
- B. 10% CO2 inhalation
- C. High flow O2 (Correct Answer)
- D. Nitroglycerine
Explanation: ***High flow O2*** - **High-flow oxygen** is the immediate emergency treatment for CO poisoning because it helps to displace CO from **hemoglobin**, thereby increasing oxygen delivery to tissues [1], [2]. - CO has a much **higher affinity** for hemoglobin than oxygen, so administering high concentrations of oxygen helps to reverse this binding and accelerate CO elimination [2]. *5% CO2 inhalation* - Administering **CO2** would worsen the patient's condition as it can cause **respiratory acidosis** and increase cerebral blood flow, potentially exacerbating CO toxicity. - CO2 inhalation would not effectively displace **carbon monoxide** from hemoglobin. *10% CO2 inhalation* - Similar to 5% CO2, **10% CO2 inhalation** would be detrimental, leading to significant **acidosis** and further compromising respiratory function. - This treatment does not address the primary issue of **carbon monoxide** binding to **hemoglobin** [2]. *Nitroglycerine* - **Nitroglycerine** is a vasodilator primarily used for conditions like **angina** or **heart failure**; it has no role in treating CO poisoning. - It would not help in displacing **carbon monoxide** or improving tissue oxygenation.
Question 18: Which subtype of Acute Myeloid Leukemia (AML) is associated with the best prognosis?
- A. Acute myelo monocytic leukemia.
- B. Acute monocytic leukemia.
- C. Erythro leukemia
- D. Acute promyeloblastic leukemia (M3) (Correct Answer)
Explanation: ***Acute promyeloblastic leukemia (M.3)*** [1] - **Best prognosis** in acute myeloid leukemia (AML) is associated with acute promyeloblastic leukemia due to its responsiveness to **all-trans retinoic acid (ATRA)** treatment. [1] - This type often presents with a **prominent coagulopathy**, but successful treatment can lead to **long-term remission**. *Acute monocytic leukemia* - Generally associated with **poor prognosis** and is characterized by a high white blood cell count and organ infiltration. - It lacks the favorable features seen in acute promyeloblastic leukemia, such as effective treatment outcomes. *Erythroleukemia* - Known for having a **poor prognosis** due to its aggressive nature and frequent association with complex chromosomal abnormalities. [1] - Treatment responses are often suboptimal compared to that of acute promyeloblastic leukemia. *Acute myelomonocytic leukemia* - Typically has an **intermediate prognosis** [1] and presents with a mixture of myeloid and monocytic features. - It does not have the same treatment responsiveness and favorable outcomes as seen in acute promyeloblastic leukemia.
Question 19: Which of the following does not predispose to leukemia?
- A. Smoking
- B. Chemical exposure
- C. Alcohol (Correct Answer)
- D. Genetic disorder
Explanation: ***Alcohol*** - Alcohol consumption does not have a well-established association with an increased risk of leukemia compared to other factors. - While excessive alcohol can impact overall health, it is not considered a primary risk factor for developing leukemia. *Chemical exposure* - Certain chemicals, such as **benzene** and **formaldehyde**, are known to be **leukemogenic** and can increase the risk of leukemia. [1] - Occupational exposure to these chemicals has been linked to **acute myeloid leukemia (AML)** and other types of leukemia. [1] *Smoking* - Smoking has been clearly associated with an increased risk of **acute myeloid leukemia (AML)** and other hematologic malignancies. [1] - The toxins in tobacco smoke can cause **DNA damage**, contributing to the development of leukemia. *Genetic disorder* - Certain genetic disorders, like **Down syndrome** and **Fanconi anemia**, are associated with an increased risk of leukemia. - Individuals with these genetic predispositions have a higher likelihood of developing various forms of leukemia.
Question 20: Shrinking Lung Syndrome is seen in:
- A. SLE (Correct Answer)
- B. Rheumatoid Arthritis
- C. Scleroderma
- D. Sarcoidosis
Explanation: ***SLE*** - **Shrinking lung syndrome (SLS)** is a rare but recognized pulmonary manifestation of **systemic lupus erythematosus (SLE)** [1]. - It is characterized by **dyspnea**, **pleuritic chest pain**, and elevated diaphragms with reduced lung volumes, often without significant interstitial lung disease [1]. *Rheumatoid Arthritis* - While **rheumatoid arthritis** can cause various lung manifestations like **interstitial lung disease (ILD)**, pleural effusions, and rheumatoid nodules, **shrinking lung syndrome** is not typically associated with it [2]. - Lung disease in RA often involves **pulmonary fibrosis** or bronchiolitis, differing from the restrictive physiology of SLS. *Scleroderma* - **Scleroderma (Systemic Sclerosis)** commonly affects the lungs, primarily leading to **interstitial lung disease (ILD)** and **pulmonary hypertension** [1]. - **Shrinking lung syndrome**, with its characteristic restrictive pattern and elevated diaphragms, is not a typical presentation of lung involvement in scleroderma. *Sarcoidosis* - **Sarcoidosis** is characterized by the formation of **non-caseating granulomas**, primarily affecting the lungs and lymph nodes. - Lung involvement in sarcoidosis typically presents as **interstitial lung disease** or nodular infiltrates, not the distinct features of **shrinking lung syndrome** [3].