Pulmonary Arteriovenous Malformations Unmasked by Refractory Hypoxia: An Unusual Presentation in Hereditary Hemorrhagic Telangiectasia

Abstract Background: Hereditary hemorrhagic telangiectasia (HHT) is a rare genetic disorder usually known to manifest with epistaxis, mucocutaneous telangiectasia, and visceral arteriovenous malformations (AVMs). Clinical Description: A 12-year-old girl presented with altered sensorium on hand ventilation, referred as a case of an acute cerebrovascular event due to cerebral AVM. She was afebrile with labored breathing and profound hypoxia. General and systemic examinations were unremarkable, except for clubbing in all digits. Management and Outcome: Investigations were largely normal, except for elevated hematocrit. Chest-X-ray showed mild infiltrates, while echocardiography was unremarkable. After stabilization and improvement of the sensorium, the child continued to have refractory hypoxemia, even with high ventilatory settings. The presence of digital clubbing and elevated hematocrit, in the background of cerebral AVM, led to suspicion of pulmonary AVM, the latter being detected by bubble contrast echocardiography and digital subtraction angiography (DSA). Genetic analysis confirmed a likely pathogenic variant in the ENG gene. Coil embolization of the pulmonary AVMs was done in stages, following which saturations improved and the child became asymptomatic. Conclusion: Persistent hypoxemia, in a child with cerebral AVMs, should raise suspicion of pulmonary AVMs, as a part of the disorder of HHT. Appropriate investigations can identify the AVMs and prompt intravascular intervention can be successful. Genetic analysis confirms the underlying HHT.