Pulmonary Arteriovenous Malformations and Cerebral Abscess Recurrence in a Child With Hereditary Hemorrhagic Telangiectasia

Hypoxemia without Respiratory Distress: Hereditary Hemorrhagic Telangiectasia in a Child

Hereditary hemorrhagic telangiectasia (HHT) is an underrecognized genetic disorder of vascular development in pediatric patients. Its presentation can range from mild cutaneous findings to life-threatening hemorrhage from arteriovenous malformations. Clinical diagnosis can be challenging in the pediatric population as disease manifestations evolve over time and may be difficult to identify in younger patients. This case highlights how nonspecific symptoms and signs in the preanesthesia period can be misleading, potentially placing a patient with unrecognized HHT at risk for significant morbidity and mortality.

Asymptomatic pulmonary arteriovenous malformations in children with hereditary hemorrhagic telangiectasia

BACKGROUND

Children with Hereditary Hemorrhagic Telangiectasia (HHT) may have pulmonary arteriovenous malformations (AVMs), which can lead to symptoms of shortness of breath, exercise intolerance, clubbing, cyanosis and hemoptysis. However, some patients with pulmonary AVMs may be asymptomatic, placing them at risk for complications such as stroke or brain abscess if they are not identified and treated. This study examines the incidence of signs and symptoms associated with pulmonary AVMs in children with HHT known to have pulmonary AVMs.

METHOD

Sixty-one children with HHT and documented pulmonary AVMs were questioned for any symptoms possibly associated with their pulmonary AVMs, prior to embolization.

RESULTS

The results show that the majority of these children were asymptomatic (56%), and their AVMs were discovered by routine screening. Those who did experience symptoms most often complained of shortness of breath and exercise intolerance, although there was a tendency to blame other conditions, such as asthma or deconditioning (being out of shape), for these symptoms. Migraine headaches were common in those with pulmonary AVMs, regardless of whether they were symptomatic or not (17 of 61 children, 28%), although they were more common in those who were symptomatic (10 of 27, 37%) versus those who were asymptomatic (7 of 34, 21%).

CONCLUSION

Children with HHT and pulmonary AVMs are often asymptomatic. Routine screening for the presence of AVMs should be performed regardless of symptomatology.

Screening children for pulmonary arteriovenous malformations: Evaluation of 18 years of experience

BACKGROUND

Hereditary Hemorrhagic Telangiectasia (HHT) is an autosomal dominant disease with multi-systemic vascular dysplasia. Early diagnosis through screening is important to prevent serious complications. How best to screen children of affected parents for pulmonary arteriovenous malformations (PAVMs) is often subject to debate. Transthoracic contrast echocardiogram (TTCE) is considered optimal in screening for PAVMs in adults. Guidelines for the screening of children are not specific, reflecting the lack of scientific evidence on the best method to use.

OBJECTIVE

Aims of this study are (i) to evaluate our current screening method, consisting of history, physical examination, pulse oximetry, and chest radiography and (ii) to assess whether postponing more invasive screening for PAVMs until adulthood is safe.

METHODS

This is a prospective observational cohort study using a patient database.

RESULTS

Over a period of 18 years (mean follow-up 9.21 years, SD 4.72 years), 436 children from HHT families were screened consecutively. A total of 175/436 (40%) children had a diagnosis of HHT. PAVMs were detected in 39/175 (22%) children, 33/39 requiring treatment by embolotherapy. None of the screened children suffered any PAVM-associated complications with this screening method.

CONCLUSION

This study shows that a conservative screening method during childhood is sufficient to detect large PAVMs and protect children with HHT for PAVM-related complications. Postponing TTCE and subsequent chest CT scanning until adulthood to detect any smaller PAVMs does not appear to be associated with major risk.

A large pulmonary arteriovenous malformation causing cerebrovascular accidents

The incidence of pulmonary arteriovenous malformations (PAVMs) is 2.5 in 100,000. 80% are associated with Osler-Weber-Rendu syndrome or hereditary haemorrhagic telangiectasia. We report the case of a 70-year-old man with a 6 cm spherical mass incidentally found on chest X-ray. There was a localised systolic bruit over the right lower zone posteriorly; however, he was asymptomatic. He had suffered a stroke, affecting his right hand and his speech, from which he recovered. He experienced regular transient ischaemic attacks, on an average of every 2 months. He underwent a right lower lobectomy and on ligating the right lower lobe pulmonary artery the saturations of oxygen rose from 92% to 97%, demonstrating a significant right to left extracardiac shunt. Postoperative recovery was excellent and 1 year later the patient reports no further neurological symptoms. 40% of such lesions exhibit symptoms, however, only one-third are neurological. Treatment should be by percutaneous embolisation.