Answer/ Explanation:Question 1
A 22-year-old man develops marked right lower quadrant abdominal pain over the past day. On physical examination there is rebound tenderness on palpation over the right lower quadrant. Laparoscopic surgery is performed, and the appendix is swollen, erythematous, and partly covered by a yellowish exudate. It is removed, and a microscopic section shows infiltration with numerous neutrophils.
The pain experienced by this patient is predominantly the result of the formation of which of the following two chemical mediators?
A Complement C3b and IgG
B Interleukin-1 and tumor necrosis factor
C Histamine and serotonin
D Prostaglandin and bradykinin
E Leukotriene and HPETE
(D) CORRECT. Aspirin, by inhibiting the cyclooxygenase pathway, can decrease prostaglandin synthesis.
A 40-year-old woman had bilateral silicone breast implants placed two years ago. Since that time, she has noted increased firmness with slight deformity of the breast on the left. The implants are removed, and there is evidence for leakage of the implant contents on the left.
Which of the following cell types is most likely to be most characteristic of the inflammatory response in this situation?
A Mast cell
C Giant cell
E Plasma cell
(C) CORRECT. The silicone is a foreign material and produces a foreign body reaction.
A 40-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.
The most critical factor in determining whether the skin in the region of the burn will regenerate following this is the presence of which of the following factors?
A Good cardiac output
B Skin appendages
C Underlying connective tissue
D Minimal edema and erythema
E Granulation tissue
(B) CORRECT. This is why a full thickness burn is much worse.
A 58-year-old woman has had a cough with fever for 3 days. A chest radiograph reveals infiltrates in the right lower lobe. A sputum culture grows Streptococcus pneumoniae. The clearance of these organisms from the lung parenchyma would be most effectively accomplished through generation of which of the following substances by the major inflammatory cell type responding to this infection?
A Platelet activating factor
E Hydrogen peroxide
(E) CORRECT. This is reduced by myeloperoxidase to a powerful oxidant that kills bacteria. In chronic granulomatous disease, this system is not operative against many bacterial species.
A clinical study is performed of patients with pharyngeal infections. The most typical clinical course averages 3 days from the time of onset until the patient sees the physician. Most of these patients experienced fever and chills. On physical examination, the most common finding is a pharyngeal purulent exudate.
Which of the following types of inflammation did these patients most likely have?
A Granulomatous inflammation
B Acute inflammation
C Abscess formation
D Resolution of inflammation
E Chronic inflammation
(B) CORRECT. The short course of days and the purulent exudate are typical features of acute inflammation.
A 56-year-old man has had increasing dyspnea for 6 years. He has no cough or fever. He was inhaling silica dust for many years in his job. A chest x-ray now shows increased interstitial markings and parenchymal 1 to 3 cm nodules. His pulmonary problems are most likely to be caused by which of the following inflammatory processes?
A Neutrophilic infiltration with release of leukotrienes
B Foreign body giant cell formation
C Plasma cell production of immunoglobulin
D Histamine release by mast cells
E Release of growth factors by macrophages
NEXT QUESTION - - INDEX OF QUESTIONS - - EXAM MENU
Premature labor with premature rupture of fetal membranes occurs at 20 weeks gestation in a 20-year-old woman. Prior to that time, the pregnancy had been proceeding normally. A stillbirth occurs two days later. Microscopic examination of the normal-sized placenta reveals numerous neutrophils in the amnion and chorion, but no villitis.
These events are most likely to be mediated by the effects from release of which of the following substances?
(B) CORRECT. This mediator of acute inflammation promotes labor through its effects on smooth muscle and blood vessels.
After two weeks in the hospital following a fall in which she incurred a fracture of her left femoral trochanter, a 76-year-old woman now has a left leg that is swollen, particularly her lower leg below the knee. She experiences pain on movement of this leg, and there is tenderness to palpation.
Which of the following complications is most likely to occur next after these events?
A Gangrenous necrosis of the foot
B Hematoma of the thigh
C Disseminated intravascular coagulation
D Pulmonary thromboembolism
E Soft tissue sarcoma
(D) CORRECT. She has deep and superficial venous thrombosis as a consequence of venous stasis from immobilization. The large deep thrombi can embolize to the lungs and lead to death.
A 40-year-old woman has had a chronic cough with fever and weight loss for the past month. A chest radiograph reveals multiple nodules from 1 to 4 cm in size, some of which demonstrate cavitation in the upper lobes. A sputum sample reveals the presence of acid fast bacilli.
Which of the following cells is the most important in the development her lung lesions?
D Mast cell
(A) CORRECT. Epithelioid cells and giant cells are derived from macrophages and are important in the development of granulomatous inflammation.
A 20-year-old man has experienced painful urination for 4 days following spring break. A urethritis is suspected, and Neisseria gonorrheae is cultured. Numerous neutrophils are present in a smear of the exudate from the penile urethra. These neutrophils are most likely to have been caused to undergo diapedesis to reach the organisms as a consequence of release of which of the following chemical mediators?
C Hageman factor
E Complement C5a
(E) CORRECT. The C5a component of complement, along with TNF, leukotrienes, and bacterial products is chemotactic for neutrophils.