Abstract

A CASE REPORT ON ACUTE CHEST SYNDROME

Sk Sharath Kumar*, Dr. Shashi Kiran D., Vasalli Sai Vinay, KR Nawaz Khan, Siddi Shoaib Akthar, Dr. Syed Mohammed Hussaini

ABSTRACT

Acute Chest Syndrome (ACS) is a life-threatening pulmonary complication and a leading cause of hospitalization and mortality in patients with sickle cell disease (SCD). It is characterized by new pulmonary infiltrates on imaging alongside clinical features such as fever, chest pain, cough, dyspnea, and respiratory distress. This report explores the clinical presentation, pathogenesis, risk factors, and emerging therapies of ACS in patients with SCD, with particular emphasis on the role of nitric oxide (NO) in pulmonary vascular regulation. The pathophysiology of ACS is complex and multifactorial, involving infection, fat embolism, pulmonary infarction, hypoventilation, and inflammation—often triggered by vaso-occlusive crises or asthma. Risk factors include younger age, low fetal hemoglobin levels, prior ACS episodes, and asthma. A key mechanism involves sickling of red blood cells in the pulmonary microvasculature, leading to hypoxia, inflammation, and impaired gas exchange. Anemiaand hemolysis further disrupt nitric oxide (NO) metabolism and impair hypoxic pulmonary vasoconstriction (HPV), contributing to ventilation-perfusion mismatch. Early recognition and aggressive supportive care are crucial to prevent progression and mortality. Diagnostic investigations include chest X-ray, full blood counts, renal and liver function tests, arterial blood gases, sputum culture and sensitivity etc. Treatment focuses on oxygen therapy to maintain saturations above 96%, pain control, empiric antibiotics, hydration, and blood transfusion when indicated. Pain management must balance efficacy with the risk of hypoventilation, and patient-controlled analgesia (PCA) is preferred over continuous opioid infusions or NSAIDS leads to side effects. Inhaled NO has demonstrated potential to temporarily improve oxygenation and reduce pulmonary pressures, though clinical evidence. Antimicrobials, particularly macrolides and cephalosporins, are recommended empirically. Advanced therapies like high-frequency oscillatory ventilation, hematopoietic stem cell transplantation, and chronic transfusions may be required in severe or recurrent cases. Management focuses on early recognition and supportive care, including oxygen therapy, patient-controlled analgesia, antibiotics, hydration, and blood transfusions. Preventive and adjunctive therapies—such as exchange transfusions, incentive spirometry, and emerging agents like NO donors, L-arginine, and bronchodilators—may reduce morbidity and recurrence. Further research is needed to validate the therapeutic role of inhaled NO and optimize treatment strategies for ACS in SCD.

Keywords: Acute chest syndrome (ACS), Acute respiratory distress syndrome (ARDS), fetal haemoglobin (HB f), patient controlled analgesia (PCA), Nitric oxide (NO), Sickle cell anemia(ACS).