Branchiootorenal Syndrome
Branchiootorenal Syndrome Definition
Branchiootorenal (BOR) syndrome is marked by malformations of the outer, middle, and inner ear associated with conductive, sensorineural, or mixed hearing impairment; branchial fistulae and cysts; and renal malformations, ranging from mild renal hypoplasia to bilateral renal agenesis. The presence, severity, and type of branchial arch, otologic, audiologic, and renal abnormality may be different from right side to left side in an affected individual and also among individuals in the same family. Some individuals develop to end-stage renal disease (ESRD) later in life. The name branciootorenal syndrome describes the body systems most frequently affected by this genetic disorder. The term "branchio" refers to the abnormalities of the neck found in people affected with this syndrome. Cysts (lump or swelling that can be filled with fluid) and fistulas (abnormal passage from the throat to the skin) in the neck appear frequently. The term "oto" refers to the ear disorders that are associated with the syndrome. For example, the outer ear can be abnormal in appearance. Hearing loss is also commonly associated to the syndrome. Finally, the term "renal" stands for the kidney problems commonly found in patients with this condition.
Branchiootorenal Syndrome Diagnosis
The diagnosis of BOR is done using clinical criteria. Molecular genetic testing of the EYA1 gene detects mutations in an estimated 40% of individuals with the clinical diagnosis of BOR syndrome.
Branchiootorenal Syndrome Symptoms and Signs
The signs associated with BOR syndrome are highly variable. Some individuals with BOR syndrome have many physical deformities. Other individuals with BOR syndrome have a very few minor physical differences. The birth defects can appear on only one side of the face (unilateral) or be present on both sides (bilateral). Abnormal development of the ears is the most frequent characteristic of BOR syndrome. The ears may be smaller than normal (microtia) and may have an abnormal shape. Ear tags (excess pieces of skin) may be seen on the cheek next to the patient's ear. Preauricular pits (small pits in the skin on the outside of the ear) are found in 75% of patients affected with BOR syndrome. Hearing loss is present in 85% of individuals with BOR syndrome and this may be mild or severe.
Branchiootorenal Syndrome Treatment
Treatment of BOR includes excision of branchial cleft cysts/fistulae, fitting with appropriate aural habilitation, and enrollment in appropriate educational programs for the hearing impaired. A canaloplasty can be taken into consideration to correct an atretic canal. Medical and surgical treatment for vesicoureteral reflux may be required. End-stage renal disease may need dialysis or renal transplantation. Surveillance of the syndrome includes semiannual examination for hearing impairment and annual audiometry to assess stability of hearing loss and semiannual/annual examination by a nephrologist if indicated.