Hereditary angioedema in Latin America: international recommendations, expert consensus, and reported implementation barriers

Background Current international hereditary angioedema (HAE) guidelines and treat-to-target recommendations emphasize accurate diagnosis, early on-demand treatment, procedure-related short-term prophylaxis, individualized long-term prophylaxis (LTP), and routine assessment of disease control and quality of life. Evidence on implementation in Latin America remains limited. We aimed to assess concordance between international guidance and the consensus of a selected Latin American expert panel and to identify expert-reported implementation barriers. Methods A scientific committee developed and externally validated a 74-item questionnaire (domains summarized in Supplementary Table S1) and conducted a two-round Delphi process among Latin American HAE experts. Consensus items were rated on a nine-point agreement scale, with consensus defined a priori as at least two-thirds of respondents scoring within a three-point band in the agreement or disagreement range. Descriptive items captured expert-reported diagnostic testing, treatment patterns, monitoring practices, and perceived implementation determinants. Consensus findings are summarized as meeting the prespecified threshold; descriptive findings are reported with item-specific n/N when available. Instrument validation (July-November 2024) showed high inter-rater agreement (Kendall W = 0.84; p < 0.001) and excellent internal consistency (Cronbach alpha = 0.92). Results Thirty experts from 10 countries completed the process (Argentina, Brazil, Chile, Colombia, Ecuador, Mexico, Panama, Peru, Uruguay, and Venezuela). The prespecified consensus threshold was met for core biochemical diagnostic work-up, selective genetic evaluation, first-line targeted LTP (pdC1-INH, lanadelumab, and berotralstat), continued availability of on-demand therapy, routine monitoring, and management of special populations. The principal expert-reported implementation signal was limited feasibility: frequent or constant prophylaxis-supply interruptions were reported by 19/30 experts (63%), including 13/23 (57%) practicing in settings where public or insurance coverage was reported. Cost (19/30; 63%) and medicine availability (8/30; 27%) were the most frequently reported barriers. These reports were not independently verified against reimbursement, procurement, formulary, or inventory data. Conclusion Within this selected panel, expert consensus was broadly concordant with international HAE guidance. Panelists reported barriers involving diagnostic testing, financing, medicine availability, and continuity of supply; however, these findings are perceptions and reported practices, not representative national or regional estimates or audited health-system data. They identify candidate implementation priorities that require confirmation through patient-level registries and objective access data.