A patient who is infected with hookworms produces signs and symptoms of anemia. Which of the following can be seen in the peripheral blood smear of the patient?

Correct Answer: B

Rationale: The correct answer is B: Basophilic stippling. Basophilic stippling is a common finding in the peripheral blood smear of patients infected with hookworms due to lead poisoning, which can occur as a result of hookworm infection. Basophilic stippling is seen as the presence of small, dark blue granules within red blood cells and is indicative of impaired heme synthesis. Howell-Jolly bodies (A) are remnants of nuclear material in red blood cells and are typically seen in patients with functional asplenia. Target cells (C) are seen in conditions such as liver disease and hemoglobinopathies. Spherocytes (D) are seen in conditions like hereditary spherocytosis or autoimmune hemolytic anemia, but not specifically in hookworm infection.

Correct Answer: C

Rationale: The correct answer is C: Microangiopathic hemolytic anemia. Schistocytes are fragmented red blood cells seen in conditions where RBCs are physically sheared or damaged as they pass through small blood vessels. In microangiopathic hemolytic anemia, abnormal or damaged blood vessels cause mechanical destruction of RBCs, leading to the formation of schistocytes. Sickle cell trait (A) and Thalassemia (B) are genetic disorders that do not typically cause schistocytes. Idiopathic thrombocytopenic purpura (D) is a condition characterized by low platelet count, not associated with schistocytes.

Correct Answer: C

Rationale: Platelets change their shape during platelet aggregation to form a plug at the site of vascular injury. This process involves platelets adhering to the injured blood vessel wall, becoming activated, and then changing shape to form a clot. Vasodilation is not an initial response, as vasoconstriction occurs to reduce blood loss. Clotting factors are essential for clot formation and play a significant role. Serotonin is released from platelets during aggregation but does not directly stimulate aggregation. The correct choice, C, directly correlates with the physiological process of platelet aggregation in response to vascular injury.

Correct Answer: B

Rationale: The correct answer is B because the Aedes mosquito, the vector for dengue fever, remains infective for life once it is infected with the dengue virus. This is due to the virus establishing a lifelong infection in the mosquito's salivary glands. The other choices are incorrect because: A) Dengue is caused by an RNA virus, not a DNA virus. C) The Aedes mosquito prefers clean, stagnant water for breeding, not polluted water. D) Joint symptoms are commoner in chikungunya, not dengue fever.

Correct Answer: C

Rationale: Virchow's node is a left supraclavicular lymph node that typically receives lymphatics from abdominal organs. The correct answer is C: prostate because the prostate is not an abdominal organ and does not drain into Virchow's node. The other choices, A: testes, B: stomach, and D: breast, all drain into the abdominal lymphatic system, making them potential sources of lymphatic drainage to Virchow's node.