Midline defects in FG syndrome: does tethered spinal cord contribute to the phenotype?

Abstract

FG syndrome is an X-linked recessive mental retardation syndrome with ano-rectal anomalies, constipation, and occasional urinary incontinence. Because tethered spinal cord syndrome (TCS) has similar symptoms, we evaluated imaging for TCS in patients with FG syndrome. Patients were recruited from the International FG Syndrome Support Group, and an FG Syndrome Consensus Group reviewed clinical histories, medical records, and photographs of each responding patient. Results of cranial and spinal imaging studies were available for 12 patients. Of 12 boys with FG syndrome, 6 had hypoplasia of the corpus callosum, and 3 of these had TCS (all with constipation and urinary symptoms). The other 9 did not have urinary symptoms. After surgical untethering, bowel and bladder symptoms improved. Tethered spinal cord syndrome occurred in 25% of patients with FG syndrome associated with hypoplasia of the corpus callosum and causing bowel and bladder incontinence. A high index of suspicion is necessary for early diagnosis, and timely intervention results in significant improvement in symptomatology.