What is the term for pulmonary infiltrates from sickle cell crisis?

From the Guidelines

The term for pulmonary infiltrates from sickle cell crisis is acute chest syndrome (ACS). This serious complication of sickle cell disease occurs when sickled red blood cells block blood vessels in the lungs, causing lung tissue damage, inflammation, and infiltrates visible on chest X-ray 1. Management typically includes supplemental oxygen, pain control, antibiotics (often a macrolide like azithromycin 500mg daily for 5 days plus a cephalosporin like ceftriaxone 1-2g daily), aggressive hydration (typically IV fluids at 1.5 times maintenance), incentive spirometry (10 breaths every 2 hours while awake), and often blood transfusions or exchange transfusions for severe cases. Early recognition is crucial as ACS can rapidly progress to respiratory failure. The pathophysiology involves multiple factors including infection, fat embolism from bone marrow infarction, hypoventilation due to pain, and direct sickling in the pulmonary vasculature. Patients with sickle cell disease who develop fever, chest pain, cough, or worsening respiratory symptoms during a vaso-occlusive crisis should be evaluated immediately for acute chest syndrome 1.

Some key points to consider in the management of ACS include:

• The clinical spectrum of ACS is variable, and although there are no specific markers of disease severity, a significant decline in the hemoglobin concentration and/or oxygen saturations (SpO2 < 94% or several percentage points below the patient’s baseline) can suggest severe disease 1.
• Interventions may include antibiotics, oxygen, invasive and non-invasive respiratory support, bronchodilators, nitric oxide, and corticosteroids 1.
• The benefit of red cell transfusion for ACS has been described in case series and observational studies, but whether simple or exchange transfusion results in improved patient outcomes is unclear 1.
• Patients with frequent ACS events also experience more morbidity, and current standard treatment of ACS prevention may include hydroxyurea (HU), chronic red cell transfusion (CRCT), and oral L-glutamine 1.

Overall, acute chest syndrome (ACS) is a life-threatening complication of sickle cell disease that requires prompt recognition and treatment 1.

From the Research

Definition of Pulmonary Infiltrates in Sickle Cell Crisis

Pulmonary infiltrates from sickle cell crisis are commonly referred to as Acute Chest Syndrome (ACS).

• ACS is defined as a new pulmonary infiltrate involving at least one complete segment of the lung, excluding atelectasis, accompanied by fever, respiratory symptoms, or chest pain 2, 3, 4, 5, 6.

Characteristics of Acute Chest Syndrome

• ACS is the leading cause of hospitalization, morbidity, and mortality in patients with sickle cell disease 2.
• The syndrome can be caused by various factors, including infection, pulmonary fat embolism, and infarction of segments of the pulmonary vasculature 2, 3, 4, 6.
• Clinical manifestations of ACS can range from mild respiratory illness to acute respiratory distress syndrome 6.

Diagnosis and Management of Acute Chest Syndrome

• Diagnosis of ACS is based on the presence of a new pulmonary infiltrate on chest X-ray, accompanied by fever and/or new respiratory symptoms 2, 3, 4, 5, 6.
• Management of ACS includes macrolide antibiotics, supplemental oxygen, modest hydration, and often simple transfusion 3.
• Other treatment strategies, such as bronchodilators and hydroxyurea, may be considered in certain cases 3, 6.