Frequency of epistaxis and telangiectasia in patients with hereditary hemorrhagic telangiectasia (HHT) in comparison with the general population: Curaçao diagnostic criteria revisited.

PURPOSE: The Curaçao criteria are well-established diagnostic criteria for hereditary hemorrhagic telangiectasia (HHT), but they lack details regarding a predictive presentation of epistaxis and telangiectasias. This study collects and compares data in HHT and population cohorts to inform the application of these criteria. METHODS: In-person interviews regarding epistaxis and targeted examination for telangiectases in a general population cohort (n = 204) and an HHT cohort (n = 432) were conducted. RESULTS: Frequency of epistaxis, rather than intensity or duration, was the best discriminator of HHT. A cutoff of ≥4 nosebleeds per year alone yielded a diagnostic sensitivity of 97%, and specificity of 84%. The mean number of telangiectases at the sites investigated was 0.4 in the general population cohort and 26.5 in the HHT cohort. The most distinctive sites for telangiectases in HHT were lips and palmar fingers, whereas telangiectases of the face and dorsum of the hand were comparable in both cohorts. CONCLUSION: We propose that the Curaçao criteria be modified to include the following cutoffs: (1) epistaxis frequency of ≥4 nosebleeds per year and (2) telangiectasia count of at least 2 in characteristic locations (palmar aspect of fingers, lips, and oral cavity), and that cutaneous telangiectases at other sites not be considered relevant for diagnostic purposes.

Curaçao diagnostic criteria for hereditary hemorrhagic telangiectasia is highly predictive of a pathogenic variant in ENG or ACVRL1 (HHT1 and HHT2).

PURPOSE: Determine the variant detection rate for ENG, ACVRL1, and SMAD4 in individuals who meet consensus (Curaçao) criteria for the clinical diagnosis of hereditary hemorrhagic telangiectasia. METHODS: Review of HHT center database for individuals with three or more HHT diagnostic criteria, in whom molecular genetic analysis for ENG, ACVRL1, and SMAD4 had been performed. RESULTS: A variant known or suspected to be causal was detected in ENG in 67/152 (44.1%; 95% confidence interval [CI], 36.0-52.4%), ACVRL1 in 79/152 (52.0%; 95% CI, 43.7-60.1%), and SMAD4 in 2/152 (1.3%; 95% CI, 0.2-4.7%) family probands with definite HHT. Only 4/152 (2.6%; 95% CI, 0.7-6.6%) family probands did not have a variant in one of these genes. CONCLUSION: Previous reports of the variant detection rate for ENG and ACVRL1 in HHT patients have come from laboratories, which receive samples from clinicians with a wide range of expertise in recognizing clinical manifestations of HHT. These studies suggest a significantly lower detection rate (~75-85%) than we have found in patients who meet strictly applied consensus criteria (96.1%). Analysis of SMAD4 adds an additional detection rate of 1.3%. HHT as defined by the Curaçao criteria is highly predictive of a causative variant in either ENG or ACVRL1.