Question 211
A 52-year-old male presents to his family physician because of prolonged weakness and some back pain. An x-ray reveals some osteolytic lesions in his cranium. A serum protein electrophoresis reveals an increased amount of protein, with a spike in the gamma region. A subsequent bone marrow biopsy reveals 25% plasma cells. One year later, the man dies and an autopsy is performed. The pathologist identifies some vessels with a thickened wall that is eosinophilic and acellular. A specific stain is ordered and illustrated below. Of the following, what substance is within the wall of the vessel?
A. Cholesterol
B. Hemosiderin
C. Foreign material
D. Amyloid
E. Fibrosis
Answer for Question 211
Answer: D (Amyloid)
Explanation: The stain is a Congo red stain, which reveals apple-green birefringence (blue arrows) when staining amyloid. In patients with multiple myeloma, the amyloid is from the excessive production of light chains.
Question 212
A 23-year-old male is drinking at a bar downtown when, after watching a football game on television, a fight ensues. During the fight, he is knocked over and falls backward, striking his head on the floor of the bar, sustaining the injury illustrated below. Of the following, how will this injury most likely heal?
A. By primary intention
B. By secondary intention
C. By tertiary intention
D. By quaternary intention
Answer for Question 212
Answer: B (By secondary intention)
Explanation: The wound is a gaping laceration with rough irregular edges. Although the wound can be sutured closed in the emergency room, the wound edges will only be approximated, resulting in more granulation tissue, and a larger more prominent scar. Healing by primary intention occurs in surgical incisions, where there is close re-approximation of the edges of the wound, minimal granulation tissue to bridge the gaps, and minimal scar formation.
Question 213
A pathologist is working with a research laboratory to develop an immunohistochemical stain that will target the pathologic change identified by the arrows in the image. Of the following, which target would be most useful to identify this cellular change?
A. Phosphatidylcholine
B. Phosphatidylinositol
C. Phosphatidylglycerol
D. Phosphatidylserine
E. Phosphatidylethanolamine
Answer for Question 213
Answer: D (Phosphatidylserine)
Explanation: The cells indicated by the arrow are hepatocytes undergoing apoptosis (note the shrunken eosinophilic cell with a pyknotic nucleus). There is no neutrophilic response. The lymphocytes are in the portal tract–the patient has hepatitis. The expression of phosphatidylserine on the surface of the cell helps the body identify the apoptotic cell and remove it, without causing a significant inflammatory response
Question 214
A 33-year-old male is found unresponsive in the morning by his wife. She calls 9-1-1; however, he is declared dead and the coroner is summoned. His wife indicates that over the last week, he has been complaining of upper respiratory tract like symptoms. He has no past medical history and no history of sudden cardiac death in his family. An autopsy is performed and identifies the pathologic finding illustrated in the image (the scissors and finger are pulling open the pericardial sac). Of the following, what is the most likely cause of this man’s death?
A. A bacterial infection
B. A fungal infection
C. A viral infection
D. A metastatic neoplasm
E. Unreported trauma
Answer for Question 214
Answer: C (A viral infection)
Explanation: The image illustrates a serous pericardial effusion (white arrow; the clear liquid, with the heart visible through the effusion. The scissors is cutting the pericardial sac), which is a watery, cell-poor effusion. A, B, and D also result in an effusion, but, the infiltrate would be cell-rich, and thus cloudy and not clear. If undiagnosed trauma produced an effusion, it would be most likely hemorrhagic.
Question 215
A pathologist is examining a section of liver from a man he autopsied who was 67 years of age and died in a motor vehicle accident. His only past medical history was hypertension and chronic obstructive pulmonary disease associated with a 40 pack-year smoking history. The pathologist identifies the change illustrated in the image in the centrilobular hepatocytes. Of the following, what is the most likely etiology for this change?
A. A genetic mutation
B. Metastatic skin neoplasm
C. Smoking
D. Bile duct obstruction
E. Cellular wear
Answer for Question 215
Answer: E (Cellular wear)
Explanation: The pigment is lipofuscin, which is wear-and-tear pigment. The centrilobular hepatocytes are the last cells in the liver to receive oxygen, and therefore, the most prone to injury. The pigment is finely stippled and yellow-brown. It is also commonly found in the heart (around the nuclei) and in the neurons in older individuals. Pigment from smoking would be in the lungs and would not deposit in the liver; melanin is usually darker, and the pigment would not be found in the liver hepatocytes. Iron can appear similar, but there is no history of hemochromatosis or reason for multiple blood transfusions in the history. A Prussian blue stain will stain iron blue. Bilirubin is usually more globular (i.e., rounded, like little globs of material), shiny or smooth in texture, and yellow-green in color; however, to absolutely distinguish hemosiderin, lipofuscin, and bile in the hepatocytes would best be done with stains directed at iron and bile to exclude their presence. The location for the lipofuscin in the image (i.e., centrilobular hepatocytes) is classic, as this area has the highest degree of “wear and tear” in the liver.
