Diagnostic value of blood coenzyme Qlo levels in children with mitochondrial diseases

То establish the diagnostic value of a change in the indicator coenzyme Qlo, its blood levels were tested in 15 children with mitochondrial diseases (Group 1). A comparison group consisted of 13 children with neurodegenerative diseases (Group 2). A control group included 29 healthy children of the same age. In Group 1 patients, the mean coenzyme Qlo level (0,56+0,06 mcmol/1) did not differ from that in the control group. However, these patients had a considerably lower coenzyme Q10/cholesterol ratio (0,10+0,01; /K0,001). The patients in the older age subgroup were found to have a significantly lower coenzyme Qlo level, which seems to reflect the progressive nature of the abnormality. There was a trend for the coenzyme Q10/cholesterol ratio to decline with age. Group 2 children had higher blood coenzyme Qlo levels (1,53+0,23; /K0,001) than Group 1 and an increased Q10/cholesterol ratio (0,31+0,04; /K0,001). It is advisable to continue the investigation to provide a rationale for using low coenzyme values as an additional criterion for the differential diagnosis of mitochondrial diseases.

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