A 55-year-old woman presents with difficulty walking and reports a feeling of 'pins and needles' in her legs. She has a history of diabetes mellitus. On examination, she has decreased sensation in the lower extremities and absent ankle reflexes. What is the most likely diagnosis?

Correct Answer: A

Rationale: The correct answer is A: Peripheral neuropathy. Given the patient's age, symptoms, history of diabetes mellitus, decreased sensation in lower extremities, and absent ankle reflexes, peripheral neuropathy is the most likely diagnosis. Peripheral neuropathy is a common complication of diabetes and presents with sensory symptoms like 'pins and needles,' decreased sensation, and loss of reflexes. Multiple sclerosis (B) typically presents with symptoms that involve the central nervous system and often presents with visual disturbances and muscle weakness. Spinal cord compression (C) typically presents with symptoms like weakness and sensory changes in specific dermatomal patterns, which are not consistent with the patient's presentation. Parkinson's disease (D) presents with motor symptoms such as tremors, rigidity, and bradykinesia, which are not seen in this patient.

Correct Answer: B

Rationale: The correct answer is B: Hypervolemia. A bounding pulse is characterized by a strong and forceful heartbeat, which is typically associated with an increased volume of blood in the circulatory system. In hypervolemia, there is an excess of fluid in the blood vessels, leading to increased pressure and volume, resulting in a bounding pulse. Hypovolemia (choice A) is characterized by decreased blood volume and would not cause a bounding pulse. Aortic stenosis (choice C) is a narrowing of the aortic valve that leads to reduced blood flow from the heart and would not typically result in a bounding pulse. Bradycardia (choice D) is a slow heart rate and is not directly related to the strength or forcefulness of the pulse.

Correct Answer: A

Rationale: Step 1: A weak and thready pulse indicates poor perfusion due to decreased blood volume. Step 2: Hypovolemia refers to low blood volume, leading to a weak pulse. Step 3: Hypervolemia is an excess of blood volume, which would not cause a weak pulse. Step 4: Aortic stenosis affects the heart valves, not directly causing a weak pulse. Step 5: Peripheral artery disease results in decreased blood flow to extremities, not affecting the pulse in general. Conclusion: The correct answer is A (Hypovolemia) because it directly correlates with the presentation of a weak and thready pulse, while the other choices are not the primary cause of this finding.

Correct Answer: B

Rationale: The correct answer is B: Pleuritis. A pleural friction rub is caused by inflammation of the pleura, the lining of the lungs and chest cavity. This rubbing together of inflamed surfaces creates a characteristic grating sound. Pleuritis is the most likely cause of this finding because it directly involves the pleura. Pneumonia (A) typically presents with crackles or decreased breath sounds. Pulmonary embolism (C) usually manifests with sudden onset chest pain and shortness of breath. Chronic obstructive pulmonary disease (D) may present with wheezing or prolonged expiration but not a pleural friction rub.

Correct Answer: D

Rationale: It does not do anything to defend the body, is not true and thus the correct answer. Fever, an elevated body temperature (also called pyrexia), is a defense mechanism against infection, enhancing immune responses like white blood cell activity and inhibiting pathogen growth. Fever is a sign of illness, is true, as it often signals infection or inflammation. It is the same as pyrexia or hyperthermia, is partially true; fever and pyrexia are synonymous, but hyperthermia (uncontrolled heat rise) differs. It is reflected through an increase of body temperature, is true by definition. Choice D is false because fever actively aids immunity, raising temperature to fight microbes, making it the statement that does not hold, per the questions intent.