Schinzel Syndrome

A very rare autosomal dominant syndrome, characterized by bone malformations and apocrine deficiency.

Ulnar Mammary Syndrome; Ulnar Mammary Syndrome of Pallister; UMS.

Autosomal dominant.

Mutations in the T-Box 3 (TBX3) gene, located on 12q24.1, are responsible for Schinzel syndrome.

Characterized by skeletal abnormalities affecting the bones of the forearms and hands. Underdevelopment and dysfunction of certain sweat glands and/or the breast is also observed.

The syndrome is associated with multiple signs: short stature, obesity, and complex skeletal malformations that can include skeletal abnormalities affecting the hands and/or forearms (hypoplasia, complete absence of the bone on the outer aspect of the forearm [ulna] and third, fourth and fifth fingers). Additionally, affected infants may have additional finger malformations with or without ulnar and/or digital abnormalities on the other side of the body. Other abnormalities associated with Schinzel syndrome include absent or incorrectly positioned (ectopic) teeth, delayed growth, uterine and vaginal abnormalities, hypogenitalism (delayed puberty), subglottic stenosis, inguinal hernia, anal atresia, pyloric stenosis, and kidney agenesia or ectopy.

It is essential to assess the condition of the apocrine system (clinical, historical); airway (clinical, fiberoptic endoscopy); and renal function (electrolytes, urea, creatinine, echography, CT scan, radionuclide imaging if necessary).

Direct laryngoscopy and tracheal intubation can be difficult because of mouth malformation and the presence of tracheal substenosis. Preserving spontaneous ventilation should be preferable until the trachea is secured and lung ventilation confirmed. The availability of a laryngeal mask airway and/or fiberoptic intubating equipment is highly recommended. Venous, arterial access, as well as blood pressure and SpO2 (arterial oxyhemoglobin saturation) measurement, can be difficult to obtain because of limb malformation. Regional anesthesia is not contraindicated but can be difficult to realize. Hyperthermia should be prevented because of apocrine gland deficiency.

Avoid parasympatholytic drugs because of a dysfunction in the sweat response. Avoid nephrotoxic drugs in cases of renal dysfunction.

Absence of Ulna and Fibula with Severe Limb Deficit (Al Awadi Teebi Farag Syndrome; Limb/Pelvis-Hypoplasia/Aplasia Syndrome; Al-Awadi Raas-Rothschild Syndrome; Schinzel Phocomelia Syndrome): Autosomal recessive with severe deficiency of all four limbs, including absent feet, hypoplastic femora, absent ulnae, absent fibulae, thoracic dystrophy, and pelvic deformity.

ADULT Syndrome: An acronym that stands for Acro-Dermo-Ungueal-Lacrimal-Tooth. The main findings are hypodontia, very brittle and/or premature loss of permanent teeth, and ectrodactyly (split hands and feet). There is no evident impairment of general health in patients with ADULT Syndrome.

Ectrodactyly, Ectodermal Dysplasia, and Clefting (EEC) Syndrome: Autosomal dominant inherited syndrome with maxillary hypoplasia, mild malar hypoplasia, cleft lip and palate, choanal atresia, hearing loss, photophobia and blepharophimosis, dacryocystitis, cryptorchidism, hypogonadotropic hypogonadism renal agenesis or dysplasia, hydronephrosis, occasionally mental retardation, central diabetes insipidus.

Limb Mammary Syndrome (LMS): This very rare syndrome is characterized by severe anomalies of the hands and feet in combination with hypoplasia or aplasia of the mammary gland and nipple. As in ADULT Syndrome, the lacrimal duct can be atretic or obstructed, the nails may be thickened and dystrophic. Hypodontia and cleft palate have been described. A newer study placed the ADULT syndrome gene locus in the same chromosome region as the LMS locus, thereby suggesting that these two conditions are allelic.

AEC Syndrome: A disorder characterized by cleft lip and/or palate, unior bilateral fusion of the eyelids, hair anomalies, onychodystrophy, hypohidrosis, and dental anomalies. The mutation has been mapped to 3q27, like all the other disorders mentioned above.