Branchio-oto-renal syndrome

Branchio‑oto‑renal syndrome (in English Branchio‑oto‑renal syndrome, BOR syndrome, branchio‑otic syndrome, branchio‑oto‑renal dysplasia, Melnick–Fraser syndrome) is a rare congenital disorder affecting approximately 1 in 40,000 individuals. The inheritance is autosomal recessive. The syndrome is characterized by hearing impairment of varying severity, renal abnormalities, gastrointestinal tract disorders, and the formation of anomalous communications in the neck region.

Causes

Several genes are known whose mutations lead to the development of this syndrome. These genes are responsible for the proper development of the neck region, the ear, and the kidneys. Gene mutations may arise de novo or be inherited from an affected parent. A parent affected by branchio‑oto‑renal syndrome has a very high likelihood that their offspring will also develop the syndrome. The inheritance is autosomal dominant. The diagnosis of the syndrome is established by genetic testing.

Treatment

Since this is a congenital syndrome, neither prevention nor causal treatment is possible. Management is focused on treating symptoms, such as hearing loss compensated with hearing aids or cochlear implants. Deformities of the neck and face are managed by plastic surgeons, ENT specialists, or oral and maxillofacial surgeons. Treatment of chronic renal failure is also required when present.

• disturbance of embryonic development in the neck region, resulting in multiple tissue abnormalities in this area. Typical is the formation of larger or smaller cavities (cysts), which may be interconnected by channels (fistulas). In some cases, these channels open onto the skin of the neck
• various facial abnormalities may also occur, for example cleft defects
• impaired development of the external, middle, or inner ear. Deformities of the auricle are primarily a cosmetic defect. Deformities of the middle and inner ear may result in mild to severe hearing loss or complete deafness of the affected ear; damage to the auditory nerve or combined involvement is also possible, as well as narrow external auditory canals
• renal involvement – one or both kidneys are poorly developed and renal function is often insufficient; this condition may lead to renal failure
• narrowed lacrimal ducts – recurrent conjunctivitis
• characteristic facial features – long and narrow face, cleft palate, paralysis (immobility) of a facial muscle or muscle group