Cystathionine β‐Synthase Deficiency in the E‐HOD Registry—Part II: Dietary and Pharmacological Treatment

• DOI: 10.1002/jimd.12844
• Publication Date: 2025-01-14T06:36:14Z
• Authors: Andrew A. M. Morris; Jitka Sokolová; Markéta Pavlíková; Florian Gleich; Stefan Kölker; Carlo Dionisi‐Vici; Matthias R. Baumg...; Luciana Hannibal; Henk J. Blom; Martina Huemer; Viktor Kožich
• Keywords: Homocystinuria

Cystathionine β-synthase (CBS) deficiency (classical homocystinuria) has a wide range of severity. Mildly affected patients typically present as adults with thromboembolism and respond to treatment pyridoxine. Severely usually during childhood learning difficulties, ectopia lentis skeletal abnormalities; they are pyridoxine non-responders (NR) or partial responders (PR) require low-methionine diet and/or betaine. The European network registry for Homocystinurias methylation Defects (E-HOD) published management guidelines CBS recommended keeping plasma total homocysteine (tHcy) concentrations below 100 μmol/L. We have now analysed data from 311 in the see how closely follows guidelines. Pyridoxine-responsive generally achieved tHcy 50 μmol/L, but many NRs PRs had mean considerably above Most were managed betaine special diet. This involved severe protein restriction methionine-free amino acid mixture, some natural intake substantially WHO safe minimum. Work is needed on methionine content dietary estimates vary widely. Contrary guidelines, most pyridoxine, sometimes at dangerously high doses. similar groups prescribed low doses intakes. High levels probably often due poor compliance. Comparing time-to-event graphs NR detected by newborn screening those ascertained clinically showed that could prevent (risk ratio 0.073) lens dislocation 0.069).