Acute chest syndrome in sickle cell disease is a pulmonary complication that is most often associated with which trigger?

• A. Infection
• B. Trauma
• C. Allergic reaction
• D. Dehydration

Answer: (A)

Infection is the trigger most commonly linked to acute chest syndrome in sickle cell disease. This syndrome arises when sickled red cells occlude the pulmonary microcirculation, leading to inflammation, edema, and a new infiltrate on imaging. Infections, especially pneumonia from bacteria or viral pathogens, provoke fever, hypoxemia, and inflammatory cascades that worsen sickling in the lungs. People with sickle cell disease have impaired splenic function, which increases susceptibility to encapsulated bacteria, making infections a frequent precipitant of ACS. Other potential factors like dehydration or trauma can contribute to sickling or lung injury, but they are less often the primary trigger for ACS compared with infection.