A 55-Year-Old Man Is Evaluated Due to Worsening Fatigue and Exertional

question 565

Multiple Choice

A 55-year-old man is evaluated due to worsening fatigue and exertional shortness of breath.  He has no chronic medical conditions and takes no medications.  Physical examination shows facial puffiness and bilateral lower extremity edema.  Urinalysis shows 3+ proteinuria.  Kidney biopsy findings with special staining under polarized light are shown on the image below: Which of the following tests would be most helpful for establishing a specific diagnosis in this patient?

• A)24-hour urinary copper excretion
• B)24-hour urinary uric acid excretion
• C)Serum protein electrophoresis
• D)Serum total bilirubin concentration
• E)Serum total body iron content

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Definitions:

V/F Principle

The principle that states the ratio of voltage to frequency (V/F) should remain constant for AC drives to maintain torque.

Voltage

An electrical measurement expressing the potential difference between two points in a circuit, typically driving current flow.

Regeneration

The process of recovering energy from a system, often from braking or decelerating, and reusing it to improve efficiency.

Induction Motors

A type of electric motor that operates on the principle of electromagnetic induction, where the rotation of the motor is caused without direct electrical connection to the rotor.