Diagnosing Mitochondrial Disorder without Sophisticated Means

Mitochondrial disorders (MIDs) require biochemical or genetic investigations for being diagnosed. In some cases, however, the diagnosis can be suspected upon the syndromic phenotype or upon clinical presentation and family history, as in the following case. The patient was a 74-year-old male admitted for worsening of pre-existing left-sided ptosis and ophthalmoparesis after a birthday party. The history was positive for arterial hypertension, hypertrophic cardiomyopathy with systolic dysfunction, diabetes-type 2, mild renal insufficiency, thyroiditis, and polyneuropathy. Instrumental investigations additionally revealed hepatopathy, hyperlipidemia, hyperuricemia, bifascicular block, white matter lesions, and subacute stroke. Systolic dysfunction resolved upon adequate cardiac treatment. On hospital day 11 the patient suddenly developed asystole. He was successfully resuscitated but died a few hours later from acute myocardial infarction. Surprisingly, a more extensive family history was positive for myopathy (patient, brother, daughter), neuropathy (patient), hypoacusis (patient), Parkinson syndrome (mother), spasticity (son), diabetes (patient, son), renal failure (patient), and generalized atherosclerosis (patient). The individual and family history was strongly suggestive of an MID. In conclusion, individual and family history may strongly suggest MID. Phenotypic variability may be high between family members affected by an MID. MID may be associated with an increasing atherosclerotic risk lastly resulting in coronary heart disease and death.