Preface: CCFDN-syndrome is a rare and complex neuro-ophthalmologic disease occurring almost exclusively in ethnic groups of Romanies. Primary symptoms are congenital cataract and microphthalmia and/or microcornea and a neuropathy with hypo- or demyelinization and progressive course. Facial abnormalities are common as well as a mild developmental delay. Further attributes are dwarfism and hypotrophy, mild hypogonadism, cerebral and spinal atrophy, osteoporosis and others, the disease pattern is variable. Attention should be paid to disposition for rhabdomyolysis during or following viral infectious diseases.