Most common cause of iron-deficiency anemia in the elderly?

Correct Answer: D

Rationale: The correct answer is D: Gastrointestinal blood loss. In the elderly, gastrointestinal blood loss is the most common cause of iron-deficiency anemia due to conditions like peptic ulcers, gastritis, and colorectal cancer. Blood loss leads to decreased iron levels, causing anemia. Malnutrition (A) can contribute but is less common in the elderly. Chronic kidney disease (B) typically leads to anemia of chronic disease, not iron-deficiency anemia. Medication side effects (C) may cause anemia, but gastrointestinal blood loss is more prevalent in the elderly population.

Correct Answer: B

Rationale: The correct answer is B: Vitamin B12 deficiency. Anemia in a strict vegetarian is likely due to inadequate intake of Vitamin B12 found in animal products essential for red blood cell production. Iron deficiency (A) is common in vegetarians but not the primary cause of anemia in this case. Erythropoietin defect (C) is rare and not specific to vegetarianism. Calcium deficiency (D) does not directly cause anemia.

Correct Answer: B

Rationale: The correct answer is B: Absolute lymphocytosis. This is the most important diagnostic criterion for Chronic Lymphocytic Leukemia (CLL). CLL is characterized by a high number of mature-looking lymphocytes in the blood. The presence of absolute lymphocytosis (>5,000/microliter) is a key feature in diagnosing CLL. Hypogammaglobulinemia (choice A) can occur in CLL but is not the primary diagnostic criterion. Male predominance (choice C) and enlarged lymph nodes (choice D) are common features of CLL but do not serve as the primary diagnostic criterion.

Correct Answer: B

Rationale: The correct answer is B: Vector infective for life. Dengue fever is caused by the dengue virus, which is transmitted to humans through the bite of infected Aedes mosquitoes. Once a mosquito is infected with the virus, it remains infective for the rest of its life, making it a lifelong vector for dengue transmission. This is why controlling mosquito populations is crucial in preventing the spread of dengue fever. Choice A (DNA virus) is incorrect because dengue fever is caused by an RNA virus, not a DNA virus. Choice C (Prefers polluted water) is incorrect as Aedes mosquitoes, the vector for dengue, breed in clean, stagnant water. Choice D (Joint symptoms more than chikungunya) is incorrect as joint symptoms are actually more common and severe in chikungunya fever, not in dengue fever.

Correct Answer: C

Rationale: The correct answer is IgE (Choice C) as it is the least present immunoglobulin in the body. IgE is primarily involved in allergic responses and defense against parasites. IgA (Choice A) is present in mucosal linings, IgD (Choice B) is involved in the activation of B cells, and IgM (Choice D) is the first antibody produced in response to an infection. Therefore, IgE is the least abundant immunoglobulin compared to the other choices.