Pediatric hemoptysis: diagnostic and interventional challenges

Hemoptysis in the pediatric population, while infrequent, poses significant challenges for both the family and healthcare practitioners. The severity of hemoptysis dictates management decisions. Most cases being mild and self-limiting are treated conservatively. However, "life-threatening hemoptysis" may occur, and is defined as any degree of blood loss that endangers the airway and is arbitrarily considered to be > 8 ml/kg in 24 h in children. It requires prompt airway management and resuscitation followed by a tailored approach consisting of bronchoscopy, computed tomography (CT), interventional radiology, and/or surgery depending on the patient 's clinical status and cardiopulmonary comorbidities. Bronchial arteries are hypertrophied in myriad conditions and account for 90-95% cases of hemoptysis due to their systemic pressure levels; the rest being contributed by pulmonary artery pathologies. Despite similar pathogenic mechanisms, the etiologies of pediatric hemoptysis differ from those in adults, with acute lower respiratory tract infections being the predominant cause. Imaging plays a crucial role in identifying the source and cause of hemorrhage. Multidetector computed tomography (MDCT) has emerged as a prime modality in the diagnostic evaluation of hemoptysis and provides a roadmap for potential interventional procedures. This article discusses the etiopathogenesis of hemoptysis along with a brief mention of the diagnostic modalities. It provides a structured reporting format and uses it to illustrate the imaging features in hemoptysis, with emphasis on CT angiography. The key findings in the lung parenchyma, airways, bronchial and non-bronchial systemic collaterals, and pulmonary arteries are elaborated upon. It further addresses the nuances of interventional management, particularly emphasizing the applications of bronchial artery embolization and pulmonary artery embolization in the pediatric population. The article also underscores the potential complications and factors influencing recurrence rates.