A 70-year-old woman has difficulty with driving, and she has been frequently getting lost. Her husband said she has also been acting strangely and seems to want to sleep a lot. He said the other night she kept saying she was seeing animals such as lions in her room. He says her memory is not too bad, but he is very concerned about her health. Physical examination reveals an alert woman with stable vital signs. Bradykinesia and limb rigidity are noted. These findings are consistent with:

Correct Answer: C

Rationale: The correct answer is dementia with Lewy bodies (DLB). Hallucinations, parkinsonian symptoms (like bradykinesia and limb rigidity), and fluctuating cognition are characteristic of DLB. Alzheimer's disease (Choice A) typically presents with memory loss as a prominent feature. Vascular dementia (Choice B) is associated with a history of strokes and step-wise cognitive decline. Frontotemporal dementia (Choice D) often presents with changes in behavior and personality rather than the parkinsonian symptoms seen in this case.

Correct Answer: B

Rationale: The correct answer is B: Underexcretion of uric acid. Gouty arthritis is primarily caused by the underexcretion of uric acid, leading to its accumulation in joints and subsequent crystallization. Choices A, C, and D are incorrect as they do not directly relate to the pathophysiology of gout. Destruction of proteoglycans, overexcretion of uric acid, and increased absorption of uric acid are not primary causes of gouty arthritis.

Correct Answer: D

Rationale: The man's presentation of large, hard nodules around his toes and elbows is indicative of tophi formation, which is characteristic of chronic gout. Tophi are deposits of uric acid crystals that can develop over time in untreated or poorly managed gout. During the chronic phase of gout, tophi can form in joints, soft tissues, and organs. Asymptomatic refers to a phase where there are no symptoms present. Acute flare is characterized by sudden and severe joint pain and inflammation. The intercritical period is the time between gout attacks when the patient is symptom-free.

Correct Answer: C

Rationale: Dark urine is a classic symptom of rhabdomyolysis. When muscle breakdown occurs, myoglobin is released into the bloodstream and filtered by the kidneys, leading to dark urine. Paresthesias (choice A) refer to abnormal sensations like tingling or numbness and are not typically associated with rhabdomyolysis. Bone pain (choice B) is not a prominent symptom of rhabdomyolysis. Diarrhea (choice D) is not a common complaint in rhabdomyolysis cases and is not directly related to muscle breakdown.

Correct Answer: B

Rationale: Bullous impetigo is the correct answer because it is caused by a Staphylococcus aureus toxin that leads to exfoliation and the formation of large blisters. Herpes simplex I virus (Choice A) causes cold sores and is not associated with exfoliation and blister formation. Necrotizing fasciitis (Choice C) is a severe skin infection involving the deeper layers of skin and subcutaneous tissues, typically caused by bacteria such as Streptococcus or Clostridium species, not Staphylococcus aureus. Cellulitis (Choice D) is a common bacterial skin infection, but it does not involve exfoliation and blister formation as seen in bullous impetigo.