Suspecting acute Pneumocystis pneumonia, which is the most important study to immediately order?

Correct Answer: A

Rationale: ABGs are critical in assessing respiratory function and oxygenation status in suspected Pneumocystis pneumonia.

Correct Answer: A

Rationale: Prolonged morning stiffness improving with use is classic for inflammatory joint pain (e.g., RA), unlike mechanical pain (worse with use) or osteoarthritis features (bone hypertrophy, osteophytes), per rheumatologic diagnostic criteria.

Correct Answer: D

Rationale: When cardiac output is reduced, juxtaglomerular cells in the kidney release renin and initiate the renin-angiotensin-aldosterone cascade leading to salt and water retention by the kidney. Aldosterone is not released from juxtaglomerular cells. Norepinephrine is not released by cells within the kidney. Angiotensin is not involved in the process of cellular release within the kidneys.

Correct Answer: C

Rationale: High Fowler's position (C) elevates the head to reduce pulmonary congestion and ease breathing in left-sided heart failure.

Correct Answer: B

Rationale: The 8th Joint National Committee's recommended goal for antihypertensive therapy for a 30- to 59-yr-old patient with hypertension is a BP below 130/80 mm Hg. The BP of 98/56 mm Hg may indicate overtreatment of the hypertension and an increased risk for adverse drug effects. The other two blood pressures indicate a need for modifications in the patient's treatment.