A 75-Year-Old Man Is Admitted to the Hospital with Fever

question 214

Multiple Choice

A 75-year-old man is admitted to the hospital with fever, chills, productive cough, and difficulty breathing.  His initial evaluation shows leukocytosis and right lower lobe consolidation.  Appropriate antibiotic therapy is started and the patient has gradual improvement.  On the third hospital day, he awakens with sudden pain and swelling of the right knee.  The patient has a history of chronic knee pain that he attributes to standing "all day, all my life" as an assembly line worker, but he has never had pain of this intensity.  Medical history is notable for hypertension, type 2 diabetes mellitus, and gastroesophageal reflux disease.
Temperature is 37 C (98.6 F) , blood pressure is 150/90 mm Hg, pulse is 84/min, and respirations are 14/min.  On examination, the patient appears uncomfortable.  The right knee joint is swollen, red, warm, and tender, and he is unable to bend the knee due to pain.
Blood cell counts and serum chemistry studies are within normal limits.  Blood culture performed at the time of admission shows no growth.  Synovial fluid analysis reveals 20,600/mm³ leukocytes with 90% neutrophils; Gram stain is negative and no crystals are visualized.  Synovial fluid culture and repeat blood cultures are sent.  Right knee x-ray is shown in the exhibit.
Which of the following is the most likely cause of this patient's knee pain?

• A)Charcot arthropathy
• B)Crystal-associated arthritis
• C)Osteoarthritis exacerbation
• D)Reactive arthritis
• E)Septic arthritis

Identify and explain different isolation mechanisms that prevent species interbreeding.

Describe how geographical features and biomes contribute to speciation.

Recognize the role of polyploidy in speciation.

Explain the fossil record's role in understanding evolutionary processes like gradualism and punctuated equilibrium.

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Definitions:

Polypropylene

A thermoplastic polymer made through the polymerization of propylene, used in packaging, textiles, and various types of containers.

Carbonate Ester

An organic compound formed by the reaction of a carbonate ion with an alcohol, often used as solvents and intermediates in chemical synthesis.

Glass Transition Temperature

The temperature range over which a polymer changes from a hard, glassy state to a soft, rubbery state.

Polymer

A large molecule or macromolecule composed of many repeated subunits.