Every patient with a diagnosis of COQ2-associated primary CoQ10 deficiency should undergo a throughout clinical assessment in order to define the severity of the disease at the diagnosis and then during the follow-up.
Management of the disease consists of the following periodic evaluations:
- Neurological evaluations with EEG analysis and brain MRI (that should be repeated even if normal at diagnosis, given the variability in the age of onset of these symptoms).
- Periodical renal function tests with urine analysis for proteinuria and nephrological evaluations.
- Screening of retinopathy/optic atrophy with periodical ophthalmological examinations.
Patients with COQ2-related CoQ10 deficiency partially respond to high dose of oral CoQ10 administration (ranging from 5 to 50 mg/kg/day): ubiquinone supplementation is able to reverse some clinical manifestations or limit their progression, but treatment must be initiated as soon as possible because irreversible neurological or renal damage cannot be corrected. In fact, patients with the neonatal onset forms show poor response, probably because therapy is started when tissue damage has become irreversible. Patients manifesting proteinuria may be treated with both CoQ10 and ACE inhibitors, whereas for patients showing end stage renal failure, renal transplantation should be considered. Standard care is indicated for retinopathy or hypertrophic cardiomyopathy. In order to prevent the onset of neurological symptoms and the progression of renal disease, high dose of CoQ10 should be administered to all patients as soon as the diagnosis is established.
Once molecular diagnosis has been achieved, relatives at risk should be analysed in order to obtain pre-symptomatic diagnosis and start early treatment with CoQ10 supplementation. There are no side effects associated with CoQ10 supplementation.