Hemoptysis is an uncommon but distressing symptom in children. It poses a diagnostic challenge as it is difficult to elicit a clear history and perform thorough physical examination in a child. The cause of
hemoptysis in children can vary with the child's age. It can range from
infection,
milk protein allergy and
congenital heart disease in early childhood, to
vasculitis, bronchial
tumor and
bronchiectasis in older children. Acute lower
respiratory tract infections are the most common cause of pediatric
hemoptysis. The objective of imaging is to identify the source of
bleeding, underlying primary cause, and serve as a roadmap for invasive procedures.
Hemoptysis originates primarily from the bronchial arteries. The imaging modalities available for the diagnostic evaluation of
hemoptysis include chest radiography, multi-detector computed tomography (MDCT), magnetic resonance imaging (MRI) and
catheter angiography. Chest radiography is the initial screening tool. It can help in lateralizing the
bleeding with high degree of accuracy and can detect several parenchymal and pleural abnormalities. However, it may be normal in up to 30% cases. MDCT is a rapid, non-invasive multiplanar imaging modality. It
aids in evaluation of
hemoptysis by depiction of underlying disease, assessment of consequences of
hemorrhage and provides panoramic view of the thoracic vasculature. The various structures which need to be assessed carefully include the pulmonary parenchyma, tracheobronchial tree, pulmonary arteries, bronchial arteries and non-bronchial systemic arteries. Since the use of MDCT entails radiation exposure, optimal low dose protocols should be used so as to keep radiation dose as low as reasonably achievable. MRI and
catheter angiography have limited application.