General pathology — Past Paper Questions & Answers

Question 1

A 40-year-old woman had laparoscopic surgery 3 months ago. Now she has a small 0.5 cm nodule beneath the skin at the incision site that was sutured. Which of the following cell types is most likely to be most characteristic of the inflammatory response in this situation?

Accepted Answer

Giant cell — The suture is a foreign material and produces a foreign body reaction. Persistence of the stimulus recruits macrophages that are activated and transformed to giant cells, in this case foreign body giant cells. ---

Question 2

A 39-year-old man incurs a burn injury to his hands and arms while working on a propane furnace. Over the next 3 weeks, the burned skin heals without the need for skin grafting. Which of the following is the most critical factor in determining whether the skin in the region of the burn will regenerate?

Accepted Answer

Persistence of skin appendages — The skin appendages have epithelium from which the surface epidermis can regenerate. A partial thickness burn retains epithelial elements in the skin. This is why a full thickness burn is much worse and requires grafting. ---

Question 3

A 36-year-old woman has been taking acetylsalicylic acid (aspirin) for arthritis for the past 4 years. Her joint pain is temporarily reduced via this therapy. However, she now has occult blood identified in her stool. Which of the following substances is most likely inhibited by aspirin to cause this complication?

Accepted Answer

Thromboxane — Asprin inhibits thromboxane A2 production by platelets, which reduces the ability of platelets to plug small vascular defects. Thromboxane is in the cyclooxygenase arm of the arachidonic acid pathway. ---

Question 4

A 17-year-old truck driver is involved in a collision. He incurs blunt force abdominal trauma. In response to this injury, cells in tissues of the abdomen are stimulated to enter the G1 phase of the cell cycle from the G0 phase. Which of the following cell types is most likely to remain in G0 following this injury?

Accepted Answer

Skeletal muscle — Skeletal and cardiac muscle cells do not typically proliferate in response to injury, and necrotic cells are replaced by connective tissue. Remaining striated muscle cells, however, can undergo hypertrophy. ---

Question 5

A 19-year-old woman who works indoors spends a day outside gardening. She does not wear a hat or sunscreen. That evening her partner remarks that her face appears red. Which of the following dermal changes most likely accounts for her red appearance?

Accepted Answer

Vasodilation — The inflammatory reaction of sunburn involves vasodilation and leakage of fluid. Vasodilation imparts a red color, which can fade quickly. Prostaglandins are generated through the cyclooxygenase pathway of arachidonic acid metabolism and induce vasodilation. Histamine contributes to vasodilation. Sunburn is typically superficial, and keratinocytes of the epidermis may undergo apoptosis and slough off. ---

Question 6

A 55-year-old man has a history of hypercholesterolemia with coronary artery disease and suffered a myocardial infarction 2 years ago. He now presents with crushing substernal chest pain. Which of the following laboratory tests is most useful in diagnosing the cause of his chest pain?

Accepted Answer

Increased serum troponin — Troponins are released from the damaged striated muscle. Cell damage leads to leakage of intracellular contents, such as enzymes or other proteins. Some of these are more specific for certain tissues to aid in diagnosis. ---

Question 7

A 45-year-old man has been working hard all day long carrying loads of bricks to build a wall. He takes a non-steroidal anti-inflammatory drug (ibuprofen). Which of the following processes is this drug most likely to diminish in his arms?

Accepted Answer

Pain — Aspirin, indomethacin, and NSAIDS block the cyclo- oxygenase arm of the arachidonic acid pathway, which generates the prostaglandins that play a role in development of pain as a consequence of the inflammatory process. The inflammation here is minimal but widespread as a consequence of the overuse of the connective tissues in the arms. ---

Question 8

A 31-year-old man has a puncture wound to his thumb, which becomes secondarily infected with Staphylococcus aureus organisms. Which of the following functions is most likely to be served by lymphatics at the site of his injury to produce a specific immune response to these organisms?

Accepted Answer

Transport antigen presenting cells — Antigen presenting cells such as dendritic cells and macrophages which have trapped antigen in peripheral tissues can be transported to lymph nodes where they encounter specific clones of memory cells capable of responding to those specific antigens, and this typically happens within a day. ---

General pathology — Past Paper Questions & Answers

Questions, Answers & Explanations