Both ENG and ACVRL1 mutations lead predominantly to underproduction of the related proteins, rather than misfunctioning of the proteins. Diagnosis
Diagnostic tests may be conducted for various reasons. Firstly, some tests are needed to confirm or refute the diagnosis. Secondly, some are needed to identify any potential complications. Telangiectasias
The skin and oral cavity telangiectasias are visually identifiable on physical examination, and similarly the lesions in the nose may be seen on endoscopy of the nasopharynx or on laryngoscopy. The severity of nosebleeds may be quantified objectively using a grid-like questionnaire in which the number of nosebleed episodes and their duration is recorded.Digestive tract telangiectasias may be identified on esophagogastroduodenoscopy (endoscopy of the esophagus, stomach and first part of the small intestine). This procedure will typically only be undertaken if there is anemia that is more marked than expected by the severity of nosebleeds, or if there is evidence of severe bleeding (vomiting blood, black stools). If the number of lesions seen on endoscopy is unexpectedly low, the remainder of the small intestine may be examined with capsule endoscopy, in which the patient swallows a capsule-shaped device containing a miniature camera which transmits images of the digestive tract to a portable digital recorder. Arteriovenous malformations
Identification of AVMs requires detailed medical imaging of the organs most commonly affected by these lesions.
The benefit from the procedure tends to be short-lived, and it may be most appropriate in episodes of severe bleeding.To more effectively minimize recurrence and severity of epistaxis, other options may be used in conjunction with therapies listed above. Intravenously administered anti-VEGF substances such as bevacizumab (brand name Avastin), pazopinab and thalidomide or its derivatives interfere with the production of new blood vessels that are weak and therefore prone to bleeding. Due to the past experiences with prescribing thalidomide to pregnant women to alleviate symptoms of nausea and the terrible birth defects that followed, thalidomide is a last resort therapy. Additionally, thalidomide can cause neuropathy. Though this can be mitigated by tinkering with dosages and prescribing its derivatives such as lenolidomide and pomalidomide, many doctors prefer alternative VEGF inhibitors. Bevacizumab has been shown to significantly reduce the severity of epistaxis without side effects.If other interventions have failed, several operations have been reported to provide benefit. One is septal dermoplasty or Saunders procedure, in which skin is transplanted into the nostrils, and the other is Youngs procedure, in which the nostrils are sealed off completely. Skin and digestive tract
The skin lesions of HHT can be disfiguring, and may respond to treatment with long-pulsed Nd:YAG laser. Skin lesions in the fingertips may sometimes bleed and cause pain. Skin grafting is occasionally needed to treat this problem.With regards to digestive tract lesions, mild bleeding and mild resultant anemia is treated with iron supplementation, and no specific treatment is administered.