Fig. 2

Treatment algorithm in AADC deficiency. This figure reflects a possible treatment scheme for a newly diagnosed AADCD patient. Drug dose and escalating schemes are given in Table 4. At the left, first line treatment is depicted in which pyridoxine is started at diagnosis (step (1)), followed after two weeks by step (2): either one of the dopamine agonists in escalating scheme or one of the MAO-inhibitors. After two months of treatment at target dose, step (3) is added: either a dopamine agonist or a MAO-inhibitor. The order of introducing dopamine agonist or MAO-inhibitors is interchangeably. Dose escalation depends on effect and tolerability. If an agent is not effective or has too many side effects, consider replacing it with another agent from the same class before going to the next step. In case of intolerable side effects, treatment should be stopped. After about 1 year in stable treatment regimen, reassessment should take place: consider to discontinue drugs (only 1 at a time) without clear treatment effect. Frequent assessment is then again necessary, and agents should be reinstated in case of deterioration. At the right, additional symptomatic treatment is depicted, with different drug classes that could be added for specific symptoms. Always avoid starting more than 1 agent at the time. Assess tolerability and effect frequently, and discontinue drugs that have no clear effect, or give intolerable side effects. Treatment in special situations (L-Dopa, folinic acid) is not depicted in this figure (see text). Abbreviations: DA-agonist: dopamine agonist; MAOI: MAO-inhibitor; OGC: oculogyric crisis