Acute Inflammation

A 28-year-old woman presents with acute onset severe left-sided pleuritic chest pain, dyspnea, and fever (39°C). Chest X-ray shows a left-sided pleural effusion. Pleural fluid analysis reveals: WBC 8,000/μL (90% neutrophils), protein 4.2 g/dL, LDH 450 IU/L, glucose 85 mg/dL, negative bacterial culture, and negative AFB smear. She is hemodynamically stable with SpO₂ 94% on room air. What is the most appropriate immediate next step?

A 28-year-old man presents with acute onset of severe testicular pain, swelling, and erythema. On examination, the spermatic cord is thickened and tender. Doppler ultrasound shows increased vascularity within the testis. Which investigation is most specific for confirming acute suppurative inflammation of the testis and excluding torsion?

A 32-year-old man presents with acute bacterial pneumonia. Regarding the sequence of cellular events in acute inflammation at the site of lung consolidation, all of the following occur in the correct temporal order EXCEPT:

Regarding the cardinal signs and mediators of acute inflammation, all of the following are correct EXCEPT:

Which of the following complement fragments is the most potent chemotactic agent and primary driver of neutrophil recruitment in acute inflammation?