Which of the following are signs of acute chest syndrome?

• A. Chest pain and fever only.
• B. Headache and confusion only.
• C. Chest pain, hypoxia, fever, and pulmonary infiltrates.
• D. Cough with clear lungs.

Answer: (C)

Acute chest syndrome in sickle cell disease shows up when the chest is involved with impaired oxygenation and a new lung infiltrate on imaging. The defining features are chest symptoms plus evidence of lung involvement and gas-exchange trouble. The best choice includes chest pain, hypoxia, fever, and a new pulmonary infiltrate, which together indicate both chest symptoms and the lung changes that define ACS. Chest pain and fever alone can occur in other conditions, and without hypoxia and a new infiltrate they don’t meet ACS criteria. Headache and confusion focus on neurologic issues rather than the chest-lung process, and coughing with clear lungs implies no lung involvement or oxygenation problems.