Abstract
This case series describes the clinical features, diagnostic challenges, treatment approaches, and outcomes of three adult patients with COQ8A-related CoQ10 deficiency presenting with focal status epilepticus, who were effectively treated at the Department of Neurology, Philipps University Marburg, Marburg, Germany. The patients, all from consanguineous families with the first two being siblings, presented with a late onset of the disease, characterized by progressive cerebellar ataxia and epilepsy, with clinical deterioration and focal status epilepticus occurring in adulthood. The first patient exhibited myoclonic status, while the second and third patients presented with bilateral tonic-clonic seizures followed by focal status epilepticus manifesting with cortical blindness. Despite differing semiologies, all patients displayed similar EEG findings with continuous or nearly continuous occipital sharp waves and spikes. MRI findings revealed focal changes in the Diffusion-Weighted Imaging (DWI) and Fluid Attenuated Inversion Recovery (FLAIR) sequences. Significant clinical improvement was observed following treatment with high doses of CoQ10, with the diffusion restriction abnormalities being reversible after therapy. In conclusion, consistent with existing literature, we observed a characteristic EEG pattern that can help identify the disease and facilitate early diagnosis and treatment. The diffusion restriction abnormalities on MRI were reversible after therapy, and high doses of CoQ10 proved beneficial even in cases of status epilepticus.