F12 and metachromatic leukodystrophy: Nine patients with comorbidities were in the aPL positive group: autoimmune disorders (2 ANAs positivity), chronic metabolic disorders (2 hypothyroidism, 1 obesity), chronic infectious disorder (1 chronic hepatitis B), obstetric disorders (2 multiple abortions) and other comorbidities (2 behavioural disorders, 1 coagulation factor XII deficiency, 1 hypoacusis, 1 metachromatic leukodystrophy).