Chapter: HHT · Osler’s disease
Article: 5 of 13
Update: May 06, 2021
Author(s): Kühnel, Thomas
Clinical symptoms may lead to the diagnosis of HHT. Epistaxis, teleangiectasias periorally, on the tongue, oral mucosa, and fingers, visceral involvement, and a positive family history are easy to record features in adults. If all these features are present, the diagnosis of HHT can be made with confidence, even without molecular genetic testing. However, molecular genetic testing may also be necessary in this case if, for example, there is uncertainty about the presence of JPHT syndrome. In addition, the existing genotype-phenotype relationship means it is possible to draw certain conclusions about organ involvement if the mutation is known (see section on genetic basis).
The above criteria were named after the consensus conference in Curaçao: If three or more criteria are met, the diagnosis of HHT is considered certain. If only two criteria are met, the suspicion remains, even if the diagnosis cannot be made. In children, neither the patient’s own medical history nor the physical examination necessarily provides conclusive indications. Therefore, the suspected diagnosis cannot be discarded without genetic exclusion (of a familial mutation), as further symptoms may develop over time. The diagnosis remains “possible” even if there is (only) a positive family history. If one parent is affected by HHT, the probability in this case is 50%.
If three or more criteria are met, the diagnosis of HHT is considered certain; if two criteria are present, the diagnosis of HHT remains suspected.
|Symptom/Findings||Relative frequency||Typical age of first occurrence|
spontaneous and recurrent
Teleangiectasias, mucocutaneous (Osler spots):
gastrointestinal, pulmonary, hepatic,
central nervous system
|Central AVM already in early childhood,|
the others from the third decade.
|Positive family history of a first-degree relative|
In the lungs and liver, bleeding is not an ostensible risk. Here, the short-circuit connections between different types of vessels are of great importance. Life-threatening complications do occur and warrant screening of the pulmonary, gastrointestinal, and central nervous systems. Even in cases where organ manifestations remain asymptomatic, early diagnosis should be made and at least observation is indicated.
Nasal bleeding limits the quality of life of patients in more than 90% of cases. It is considered the leading symptom of the disease and typically occurs first − frequently before puberty, but almost always by age 40. Teleangiectasia increases from the third decade. Anterior rhinoscopy and endoscopy of the nose provide the experienced examiner with reliable clues to the diagnosis (see above).