Dopamine beta (β)-hydroxylase deficiency is a condition that affects the autonomic nervous system (ANS). The ANS works via two opposing branches, the sympathetic and parasympathetic, both of which antagonistically control involuntary processes that regulate bodily homeostasis. Problems related to DβH deficiency often first appear as complications shortly after birth. Postnatal episodes may include vomiting, dehydration, hypotension, muscle hypotonia, hypothermia, and hypoglycemia. Due to the deficiency of norepinephrine and epinephrine those affected by dopamine β-hydroxylase deficiency may present with droopy eyelids (ptosis), nasal congestion, and hypotension. The most common complaint of individuals with dopamine β-hydroxylase deficiency is orthostatic hypotension. The symptoms associated with orthostatic hypotension are dizziness, blurred vision, or fainting upon standing. Therefore, DβH deficiency patients may have an inability to stand for a prolonged period of time. This phenomenon is especially pronounced when going from supine to upright positions, such as getting out of bed in the morning. It is also worsened by extreme climates due to loss of fluid through excessive sweating. The inability to maintain normal blood pressure makes it difficult for people with DβH deficiency to exercise (exercise intolerance). Males with DβH deficiency may experience retrograde ejaculation, a discharge of semen backward into the bladder due to dysmotility of their smooth muscle, which as innervated by the ANS. A subset of DβH deficiency patients present with hypermobility. Postural orthostatic tachycardia syndrome, another form of dysautonomia, also sees this comorbidity with hypermobility in the form of a rare connective tissue disorder called Ehlers Danlos syndrome. Another commonly experienced symptom is hypoglycemia, which is thought to be caused by adrenomedullary failure. In looking at the cardiovascular system, a loss of noradrenergic control is seen as T-wave abnormalities on electrocardiogram. Prolactin is frequently suppressed by excessive dopamine found in the patient's central nervous system. Excess dopamine can also affect digestion, producing vomiting and inhibiting motor signaling to the GI tract.
Dopamine beta hydroxylase deficiency
Aromatic L-amino acid decarboxylase deficiency
Dopamine transporter deficiency syndrome
Cerebral creatine deficiency
N-Acetylglutamate synthase deficiency
Prolidase deficiency
Beta-ketothiolase deficiency
Pantothenate kinase-associated neurodegeneration