Congenital Cataracts-Facial Dysmorphism-Neuropathy Syndrome

Congenital Cataracts Facial Dysmorphism Neuropathy (CCFDN) syndrome is a complex developmental disorder of autosomal recessive inheritance.

Epidemiology

To date, CCFDN has been found to occur exclusively in patients of Roma (Gypsy) ethnicity; over 100 patients have been diagnosed.

Clinical description

Developmental abnormalities include congenital cataracts and microcorneae, primary hypomyelination of the peripheral nervous system, impaired physical growth, delayed early motor and intellectual development, mild facial dysmorphism and hypogonadism. Para-infectious rhabdomyolysis is a serious complication reported in an increasing number of patients. During general anaesthesia, patients with CCFDN require careful monitoring as they have an elevated risk of complications.

Etiology

CCFDN is a genetically homogeneous condition in which all patients are homozygous for the same ancestral mutation in the CTDP1 gene. CTDP1 maps to 18qter and encodes a protein phosphatase whose only known substrate is the phosphorylated serine residues of the carboxy-terminal domain of the largest subunit of RNA polymerase II, indicating that CCFDN affects basic cellular processes of gene expression and developmental regulation.

Diagnostic methods

Diagnosis is clinical and is supported by electrophysiological and brain imaging studies. The definitive diagnosis is molecular, based on homozygosity for the CTDP1 mutation.

Differential diagnosis

The major differential diagnosis is Marinesco-Sjogren syndrome.

Genetic counseling

Families benefit from genetic counselling and predictive testing.

Management and treatment

Management includes surgical treatment of the cataracts, and rehabilitation and corrective orthopaedic surgery for the peripheral neuropathy.

Prognosis

Thus, the most disabling manifestations, though not curable, are manageable, and allow an acceptable quality of life and everyday living. Current data indicate that patients survive well into adulthood.