REAR Syndrome

A very rare syndrome that can also be associated with cardiac and neurological anomalies. REAR is an acronym that stands for: Renal-Ear-Anal-Radial.

Townes-Brocks Syndrome; Imperforate Anus, Hand, Foot, and Ear Anomalies; Sensorineural Deafness with Imperforate Anus and Hypoplastic Thumbs Syndrome; Branchiootorenal-like Syndrome.

Autosomal dominant, total penetrance, variable expressivity. The gene (SALL1) is mapped on chromosome 16 (16q12.1).

Caused by consequence of a mutation in a gene coding for a transcription factor.

Association of four signs: anorectal malformations (80%), hand and feet deformities (50%), external ear abnormalities (65%), sensorineural deafness (40%).

Features include gastrointestinal signs (duodenal atresia, imperforate anus, anal stenosis, anterior placement of anus, rectovaginal/rectoperineal fistula), abnormality of the extremity (radial ray deformities, broad thumb, bifid thumb, triphalangeal thumb, preaxial polydactyly, syndactyly, fusion of metatarsals, absent/hypoplastic third toe, fifth toe clinodactyly, pseudoepiphysis of second metacarpal), ear deformations (overfolding of superior helix, large ears, preauricular tags, preauricular pits, microtia satyr ear, sensorineural hearing), cardiovascular anomalies (e.g., tetralogy of Fallot or ventricular septal defect), microcephaly (with some cases of mental retardation), and multiple genitourinarydeformations (hypospadias, bifid scrotum, prominent midline perineal raphe, hypoplastic kidneys, vesicoureteral reflux, urethral valves, multicystic kidneys, dysplastic kidneys, renal failure).

Evaluate cardiac function (clinical, ECG, echocardiography, radionuclide imaging if necessary); renal function (blood analysis: kaliemia, creatinine, sodium, abdominal echography, eventually CT scan).

Anesthetic management will be adapted to both cardiopathy and renal status. Venous access and pulse oximetry can be more difficult because of extremity deformities. Fluid regimen must be adapted to renal status. Prophylactic antibiotics must be done in case of cardiopathy.

Avoid cardiac-depressive drugs; prefer drugs with hepatic or plasmatic metabolism. Aminoglycosides are not contraindicated but must be adapted to renal clearance and benefit has to be clearly evaluated in case of renal insufficiency and incomplete deafness. Prophylactic antibiotics in case of cardiopathy as indicated.

Holt-Oram Syndrome: Characterized by thumb anomaly and atrial septal defect, although abnormality of the upper extremities can be more extensive in some cases. The thumb may be absent or may be a triphalangeal, nonopposable, finger-like digit. Upper extremity phocomelia and ventricular septal defect have been reported in few patients.

Imperforate Anus: A rare abnormality that can occur alone or as an anomaly of another disorder.

VA(C)TER(L) Association is an acronym for (V)ertebral anomalies, (A)nal atresia, (T)racheo(E)sophageal fistula and (R)enal anomalies. Abnormalities are present at birth. This syndrome is different than the REAR Syndrome.