Clinical Indication ID & Name
Hereditary haemorrhagic telangiectasia
Test Group
Respiratory
Test code
R186.1
Test name
N/A
Target genes
Hereditary haemorrhagic telangiectasia (123)
Test scope
n/a
Test method/ technology
Small panel
Optimal Family Structure
n/a
Eligibility Criteria
Test where any THREE of the following criteria are met:
1. Epistaxis: spontaneous, recurrent nose bleeds
2. Telangiectases: multiple, at characteristic sites (lips, oral cavity, fingers, nose)
3. Visceral lesions such as gastrointestinal telangiectasia (with or without bleeding), pulmonary
arteriovenous malformation (AVM), hepatic AVM, cerebral AVMs, spinal AVM
4. Family history: a first degree relative with HHT according to these criteria (as above) or an autosomal dominant family history of nosebleeds or first degree relative with cerebral AVM / cerebral haemorrhage / pulmonary or hepatic AVM.
Alternatively, test where any ONE of the following criteria are met:
A) Personal history of at least one pulmonary AVM*
B) Personal history of two or more AVMs at one or more characteristic sites (pulmonary*, cerebral, hepatic or spinal)
C) Personal history of at least one AVM and severe epistaxis or characteristic telangiectasia or family history
D) Personal history of telangiectasia, and refractory or severe epistaxis (e.g. requiring recurrent
transfusions) *
*Pulmonary AVM only if confirmed by cross sectional imaging (usually thoracic CT scan), and/or later therapeutic angiography/surgery. Do not diagnose if only supported by a positive right-to-left shunt study (“bubble echo”) or chest x-ray.
To Note: if there is no antecedent family history implying a “first in family” case more likely to be
mosaic.
Test code
R186.2
Test name
N/A
Target genes
Hereditary haemorrhagic telangiectasia (123)
Test scope
n/a
Test method/ technology
Exon level CNV detection by MLPA or equivalent
Optimal Family Structure
n/a
Eligibility Criteria
Test where any THREE of the following criteria are met:
1. Epistaxis: spontaneous, recurrent nose bleeds
2. Telangiectases: multiple, at characteristic sites (lips, oral cavity, fingers, nose)
3. Visceral lesions such as gastrointestinal telangiectasia (with or without bleeding), pulmonary
arteriovenous malformation (AVM), hepatic AVM, cerebral AVMs, spinal AVM
4. Family history: a first degree relative with HHT according to these criteria (as above) or an autosomal dominant family history of nosebleeds or first degree relative with cerebral AVM / cerebral haemorrhage / pulmonary or hepatic AVM.
Alternatively, test where any ONE of the following criteria are met:
A) Personal history of at least one pulmonary AVM*
B) Personal history of two or more AVMs at one or more characteristic sites (pulmonary*, cerebral, hepatic or spinal)
C) Personal history of at least one AVM and severe epistaxis or characteristic telangiectasia or family history
D) Personal history of telangiectasia, and refractory or severe epistaxis (e.g. requiring recurrent
transfusions) *
*Pulmonary AVM only if confirmed by cross sectional imaging (usually thoracic CT scan), and/or later therapeutic angiography/surgery. Do not diagnose if only supported by a positive right-to-left shunt study (“bubble echo”) or chest x-ray.
To Note: if there is no antecedent family history implying a “first in family” case more likely to be
mosaic.
Commissioning group
Specialised
Overlapping idications
n/a
Address for samples/request forms
North Thames GLH, Rare & Inherited Disease Genomic Laboratory
Specimen Reception, Level 5 Barclay House, 37 Queen Square,
London WC1N 3BH
Contact with queries
Supporting documents
n/a
Education resources
n/a
Service updates
n/a
Request form download
Consent record
See consent guidance in test request form
Sample requirements
See sample guidance in test request form