Allergic Reaction to Aminophylline in a Case of Lower Respiratory Tract Infection with Measles: A Rare Case Report

Abstract

Measles is an acute respiratory infectious disease caused by the measles virus. It leads to respiratory involvement with manifestations such as pneumonia, laryngobronchitis, pneumonitis, etc. It can also cause secondary bacterial and fungal infections. Aminophylline is a methylxanthine bronchodilator composed of theophylline and ethylenediamine. Airway blockage is reversed by bronchial smooth muscle relaxation, increased myosin light chain kinase activity, and decreased intracellular calcium concentration. It relaxes the smooth muscle of the bronchial airways and pulmonary blood vessels, reducing airway responsiveness to histamine, methacholine, adenosine, and allergens. Allergic skin reactions secondary to aminophylline administration have been rarely seen. Aminophylline can be given orally as well as intravenously. A seven-month-old male infant presented with a lower respiratory tract infection and a maculopapular rash involving the face and trunk. A history of contact with measles was present. Intravenous aminophylline was administered for persistent wheezing. The infant developed a generalised erythematous papular rash with a more widespread distribution than before within one hour of administration. The child was treated with antihistamines for the same. After a detailed physical examination, looking at the pattern of the rash and excluding other causes like environmental factors and drug history, the diagnosis of an allergic reaction to aminophylline was made. Early identification of allergic reactions is paramount, as prompt cessation of the offending agent and initiation of appropriate medical interventions can significantly mitigate the severity of the reaction and prevent potential life-threatening complications.