Systemic Pathology Practice Questions

Question 1

A 78-year-old man dies suddenly from complications of acute kidney failure. An autopsy is performed and microscopic evaluation of the kidneys shows pale, swollen cells in the proximal convoluted tubules. Microscopic evaluation of the liver shows similar findings. Which of the following is the most likely underlying mechanism of these findings?

Accepted Answer

Impaired Na+/K+-ATPase pump activity

Answer

Double-stranded DNA breakage

Answer

Free radical formation

Answer

Cytochrome C release

Answer

Cytoplasmic triglyceride accumulation

Question 2

A scientist in Chicago is studying a new blood test to detect Ab to EBV with increased sensitivity and specificity. So far, her best attempt at creating such an exam reached 82% sensitivity and 88% specificity. She is hoping to increase these numbers by at least 2 percent for each value. After several years of work, she believes that she has actually managed to reach a sensitivity and specificity much greater than what she had originally hoped for. She travels to China to begin testing her newest blood test. She finds 2,000 patients who are willing to participate in her study. Of the 2,000 patients, 1,200 of them are known to be infected with EBV. The scientist tests these 1,200 patients' blood and finds that only 120 of them tested negative with her new exam. Of the patients who are known to be EBV-free, only 20 of them tested positive. Given these results, which of the following correlates with the exam's specificity?

Accepted Answer

98%

Answer

82%

Answer

90%

Answer

84%

Answer

86%

Question 3

A 23-year-old woman is brought to the emergency department 30 minutes after stepping on a piece of broken glass. Physical examination shows a 3-cm, ragged laceration on the plantar aspect of the left foot. The physician uses hydrogen peroxide to clean the wound. Which of the following is the most likely mechanism of action of this disinfectant?

Accepted Answer

Formation of free radicals

Answer

Intercalation of DNA

Answer

Crosslinking of proteins

Answer

Halogenation of nucleic acids

Answer

Congealing of cytoplasm

Question 4

You conduct a medical research study to determine the screening efficacy of a novel serum marker for colon cancer. The study is divided into 2 subsets. In the first, there are 500 patients with colon cancer, of which 450 are found positive for the novel serum marker. In the second arm, there are 500 patients who do not have colon cancer, and only 10 are found positive for the novel serum marker. What is the overall sensitivity of this novel test?

Accepted Answer

450 / (450 + 50)

Answer

450 / (450 + 10)

Answer

490 / (10 + 490)

Answer

490 / (50 + 490)

Answer

490 / (450 + 490)

Question 5

A research team is studying the effects of a novel drug that was discovered to treat type 2 diabetes. In order to learn more about its effects, they follow patients who are currently taking the drug and determine whether there are adverse effects that exceed anticipated levels and may therefore be drug-related. They discover that the drug causes an excess of sudden cardiac death in 19 patients with renal failure out of 2 million total patients that are followed. Based on these results, an additional warning about this serious adverse effect is added to the investigator brochure for the drug. Which of the following clinical phase studies does this study most likely describe?

Accepted Answer

Phase IV

Answer

Phase II

Answer

Phase V

Answer

Phase III

Answer

Phase I

Question 6

An epidemiologist is evaluating the efficacy of Noxbinle in preventing HCC deaths at the population level. A clinical trial shows that over 5 years, the mortality rate from HCC was 25% in the control group and 15% in patients treated with Noxbinle 100 mg daily. Based on this data, how many patients need to be treated with Noxbinle 100 mg to prevent, on average, one death from HCC?

Accepted Answer

10

Answer

20

Answer

73

Answer

50

Answer

100

Question 7

A 57-year-old man is admitted to the ER due to an abrupt onset of abdominal pain that radiates to the back, nausea, and multiple vomiting episodes for the past 10 hours. He does not have any significant past medical history. He admits to drinking alcohol every night. During admission, he is found to have a body temperature of 37.5°C (99.5°F), a respiratory rate of 20/min, a pulse of 120/min, and a blood pressure of 120/76 mm Hg. He looks pale with sunken eyes and has significant epigastric tenderness and flank discoloration. An initial laboratory panel shows the following:
Total count (WBC) 10,000/mm3
Platelet count 140,000/mm3
Serum glucose 160 mg/dL
Serum LDH 500 IU/L
Aspartate aminotransferase 400 IU/dL
Serum Amylase 500 IU/L
Serum Lipase 300 IU/L
Which of the following combinations would best predict severity in this case?

Accepted Answer

Age, LDH, AST

Answer

WBC, platelet count, AST

Answer

Age, glucose, amylase

Answer

Glucose, LDH, AST

Answer

AST, amylase, lipase

Question 8

A 69-year-old man presents with progressive malaise, weakness, and confusion. The patient’s wife reports general deterioration over the last 3 days. He suffers from essential hypertension, but this is well controlled with amlodipine. He also has type 2 diabetes mellitus that is treated with metformin. On physical examination, the patient appears severely ill, weak and is unable to speak. His neck veins are distended bilaterally. His skin is mottled and dry with cool extremities, and he is mildly cyanotic. The respiratory rate is 24/min, the pulse is 94/min, the blood pressure is 87/64 mm Hg, and the temperature is 35.5°C (95.9°F). Auscultation yields coarse crackles throughout both lung bases. Which of the following best represents the mechanism of this patient’s condition?

Accepted Answer

Cardiac pump dysfunction

Answer

Barrier to cardiac flow

Answer

Failure of vasoregulation

Answer

Restriction of cardiac filling

Answer

Loss of intravascular volume

Question 9

A 62-year-old man is brought to the emergency department with fatigue, dry cough, and shortness of breath for 3 days. He reports a slight fever and has also had 3 episodes of watery diarrhea earlier that morning. Last week, he attended a business meeting at a hotel and notes some of his coworkers have also become sick. He has a history of hypertension and hyperlipidemia. He takes atorvastatin, hydrochlorothiazide, and lisinopril. He appears in mild distress. His temperature is 102.1°F (38.9°C), pulse is 56/min, respirations are 16/min, and blood pressure is 150/85 mm Hg. Diffuse crackles are heard in the thorax. Examination shows a soft and nontender abdomen. Laboratory studies show:
Hemoglobin 13.5 g/dL
Leukocyte count 15,000/mm3
Platelet count 130,000/mm3
Serum
Na+ 129 mEq/L
Cl- 100 mEq/L
K+ 4.6 mEq/L
HCO3- 22 mEq/L
Urea nitrogen 14 mg/dL
Creatinine 1.3 mg/dL
An x-ray of the chest shows infiltrates in both lungs. Which of the following is the most appropriate next step in diagnosis?

Accepted Answer

Urine antigen assay

Answer

CT Chest

Answer

Direct immunofluorescent antibody test

Answer

Stool culture

Answer

Polymerase chain reaction

Question 10

A pathologist receives a patient sample for analysis. Cells in the sample are first labeled with fluorescent antibodies and then passed across a laser beam in a single file of particles. The light scatter and fluorescent intensity of the particles are plotted on a graph; this information is used to characterize the sample. This laboratory method would be most useful to establish the diagnosis of a patient with which of the following?

Accepted Answer

Pancytopenia and deep vein thrombosis with intermittent hemoglobinuria

Answer

Ventricular septal defect and facial dysmorphism with low T-lymphocyte count

Answer

Painless generalized lymphadenopathy with monomorphic cells and interspersed benign histiocytes on histology

Answer

Multiple opportunistic infections with decreased CD4 counts

Answer

Vesicular lesions with dermatomal distribution and dendritic corneal ulcers

Systemic Pathology

Study Resources

Lessons

Questions

Flashcards

Lessons

Liver pathology (hepatitis, cirrhosis)

Gallbladder and biliary tract disorders

Pancreatic diseases

Kidney diseases

Male reproductive pathology

Female reproductive pathology

Breast pathology

Endocrine pathology

Bone and joint pathology

Skeletal muscle diseases

Peripheral nerve disorders

Soft tissue tumors

Head and neck pathology

Practice Questions

Flashcards

About Systemic Pathology for USMLE

Lessons in Systemic Pathology

Master Systemic Pathology