What is Acute Chest Syndrome?

Acute chest syndrome (ACS) is a serious pulmonary condition that occurs in individuals with sickle cell anemia. Adversely impacting one’s lung function, acute chest syndrome can quickly jeopardize one’s life if medical attention is absent or delayed. Treatment for this potentially fatal complication is generally multi-faceted, including the administration of supplemental oxygen and blood transfusion.

There is no known cause for the development of acute chest syndrome. Individuals recently diagnosed with a secondary infection, especially one that affects the lungs, and those who have undergone a recent surgery are considered at an increased risk for developing this painful lung condition. In some cases, trauma or impaired circulation due to the presence of a blood clot can also induce ACS symptoms.

Individuals with sickle cell disease produce hemoglobin S, which adversely affects circulation and can directly impact pulmonary function. The rigidity and composition of sickled red blood cells cause them to stick together, forming clots that slow the delivery of oxygenated blood throughout the body. When the lungs are deprived of oxygenated blood, lung tissue can suffer damage resulting in fluid accumulation, impaired respiration and tissue scarring. Decreased oxygen levels in the blood and lungs, as occurs with repeated episodes of ACS, can result in lasting pulmonary damage and an increased risk for pulmonary hypertension.

A chest X-ray is generally performed to confirm a diagnosis of acute chest syndrome. Symptomatic individuals will also usually demonstrate an increased white blood cell count, due to the presence of infection, and decreased blood platelet and hemoglobin levels. In some cases, a blood culture may be performed to identify the bacterial presence that caused symptoms. Additional testing may also include a bronchoscopy and arterial blood gas analysis.

Children and adolescents are considered at greatest risk for developing acute chest syndrome. Adults diagnosed with ACS will often experience more pronounced symptoms than younger people. Symptoms of acute chest syndrome will usually include persistent cough, shortness of breath and chest discomfort. It is not uncommon for individuals with ACS to also develop fever and chills.

Due to the rapidity with which ACS symptoms may develop and progress, individuals exhibiting symptoms must seek immediate medical treatment. Often requiring hospitalization, ACS necessitates the aggressive administration of antibiotic and analgesic medications to eliminate infection and alleviate pain. Individuals with acute chest syndrome often require supplemental oxygen to ease respiration and intravenous (IV) fluids to prevent dehydration. Due to the risk for pulmonary edema, individuals receiving IV fluids must remain under observation.

A blood transfusion is generally performed to help prevent further pulmonary damage. Considering the risk for iron accumulation within one’s system, the regular use of transfusion therapy to treat recurrent episodes of acute chest syndrome is closely monitored. Those who undergo repeated transfusions may require regular chelation therapy to eliminate excess iron from their system.