Question 221
A 48-year-old male is involved in a motor vehicle accident and sustains a fracture of his left and right femur. His extrication from the car is difficult and on the way to the hospital, he sustains a cardiac arrest secondary to blood loss. He is resuscitated successfully. One day later, he complains of nausea and vomiting. Physical examination reveals a slightly enlarged and tender liver. Laboratory testing reveals elevated ALT and AST. The microscopic appearance of his condition is shown in the image. Of the following, what is the most likely etiology for his symptoms.
A. Undiagnosed hepatic trauma
B. Fat necrosis
C. Hypotension
D. Bacterial infection
E. Unspecified toxin exposure
Answer for Question 221
Answer: C (Hypotension)
Explanation: The patient has ischemic hepatitis–the pathologic change is centrilobular necrosis, which is commonly due to impaired perfusion of the liver due to hypotension (as could occur with blood loss and cardiac arrest). Blood enters the hepatic lobule at the portal tract (these cells survive in patients with centrilobular necrosis because they get the oxygen first) and filters down to the central vein (these cells die in patients with centrilobular necrosis, because they get oxygenated blood last, and with hypotension, may not be perfused). The cells around the central vein are undergoing coagulative necrosis. The dashed yellow line is the very rough dividing line between histologically viable hepatocytes and those undergoing necrosis.
Question 222
A 67-year-old male presented to his family physician with complaints of a painful red nodule on his hand. A short time ago, he was working outside on his farm and cut his hand on his plow. He washed the wound when he was done with his work, and did not think twice about it. He has no history of drug use and has only had one sexual partner during his life, his wife of 44 years. He has had type II diabetes mellitus for 10 years. A biopsy of the wound reveals the findings illustrated in the image below. Of the following, what is the most likely diagnosis?
A. Xanthoma
B. Calcinosis
C. Gaucher disease
D. Cryptococcal infection
E. Cytomegalovirus infection
F. Granulomatous inflammation
Answer for Question 222
Answer: D (Cryptococcal infection)
Explanation: Although the man is not immunocompromised, Cryptococcal infections can occur in immunocompetent individuals. Skin infections are one manifestation, and most commonly occur in males. In tissue, the characteristic capsule (blue arrow) surrounding the fungal organism (yellow arrow) is easily identified; however, the organism can be highlighted with PAS or mucicarmine.
Question 223
A surgical pathologist is examining a liver biopsy from a patient in the hospital who is being seen by the internal medicine service. He identifies the microscopic finding illustrated in the image. Of the following, what would examination of the patient reveal?
A. Large bruise on the chest
B. Fingers with remote burnt skin (dry and yellow)
C. Large dark black mole on the back
D. Yellow skin
E. Prominent psoriasis
F. Fungal skin infection
G. Numerous tattoos
Answer for Question 223
Answer: D (Yellow skin)
Explanation: The pigment is bile (blue arrows); which can appear more globular (rounded) and yellow-green than other pigments (lipofuscin is more finely stippled; hemosiderin is most often more variable in size or chunky in appearance); patients who are jaundiced (i.e., the yellow skin) can have evidence of cholestasis (bile accumulation) in the liver. No fungal organisms are present. A large bruise would not result in a deposition of iron in the liver that is so easily identifiable as the pigment in the image. Melanin, associated with melanoma, is more often finely stippled and black. Tattoo pigment remains localized. Fingers with dry yellow discolorations is consistent with a smoker; smoker’s pigment is finely stippled and brown-yellow or black, and occurs in the lung, not the liver. Psoriasis is not commonly directly associated with pigmentation of the internal organs.
Question 224
An autopsy pathologist has during three separate cases identified a nodule in the thyroid gland such as that illustrated in the image below. She hypothesizes that the nodule was from a past episode or episodes of hemorrhage into the gland. If her hypothesis is correct, of the following, which component of the red blood cell most contributed to the changes seen in the image.
A. Plasma membrane
B. Hemoglobin
C. Iron
D. Nuclear membrane
E. Nucleolus
Answer for Question 224
Answer: A (Plasma membrane)
Explanation: At the blue arrows (and around the arrows at the same area) are cholesterol clefts. Cholesterol is a major component of the plasma membrane. Hemoglobin would be a protein accumulation and iron is not present (based upon this view). A red blood cell lacks a nucleus, so nuclear membrane and nucleolus would not contribute.
Question 225
A 71-year-old female is eating lunch with friends when she suddenly drops her fork and fumbles to pick it up. Her friends call 9-1-1 and she is transported to the hospital, where she is diagnosed with a minor stroke of her left frontal lobe. Six days later, she sustains an acute myocardial infarct in the hospital and dies. Her family requests an autopsy and the pathologist identifies a soft 2.0 cm region in her left frontal lobe; the microscopic appearance is illustrated below. Of the following, what is the main process occurring here?
A. Coagulative necrosis
B. Liquefactive necrosis
C. Apoptosis
D. Hemorrhage
E. Undiagnosed fungal infection
Answer for Question 225
Answer: B (Liquefactive necrosis)
Explanation: The neurons are dead (none are visible) and the architecture is not identifiable; there are many foamy macrophages–the macrophages are derived from microglial cells, mainly, and some blood macrophages, and engulf myelin so they become foamy. Yes, there is hemorrhage, but it is not the main process–hemorrhage can be a secondary event in many lesions. The foamy macrophages are on centered in the lower left side of the image.
