Karsch-Neugebauer Syndrome

At a glance

Inherited polymalformative syndrome characterized by the presence of split-hand and split-foot in association with nystagmus. The pathognomonic characteristic is the congenital absence of the middle digit and the shape of the hand like a claw. Other features include hypodontia, delayed teeth eruption, variation in morphology, and position of teeth.

History

This syndrome occurs in association with congenital nystagmus and was named after J. Karsch and H. Neugebauer.

Incidence

It affects about 1 in 90,000 babies, with males and females equally being affected.

Genetic inheritance

Its pattern of inheritance is autosomal dominant. However, it is believed that it can occasionally skip a generation. A total of 15 cases have been reported in the literature. Autosomal dominant transmission, although some cases appear to occur as a consequence of gonadal mosaicism (unaffected parents giving rise to affected children).

Clinical aspects

Ocular signs include undulatory nystagmus, retinopathy, ocular muscle paresis, and, in some cases, cataracts. Classic split-hand/split-foot abnormality (ectrodactyly or lobster claw deformity) (occasionally with an articulating “cross bone”) and monodactyly are associated with this medical condition. It is important to evaluate the dental condition in preparation for the laryngoscopy.

Anesthetic considerations

No significant anesthetic concerns directly associated with this medical condition. Peripheral vascular access may be challenging given the anatomical anomalies. Special attention must be given to the dental condition to avoid damage during airway management.

Other conditions to be considered

Split-hand/split-foot deformity may also be present in the following conditions:

• ☞Acro-Renal-Mandibular Syndrome: Characterized by severe split-hand/split-foot malformation in association with urogenital anomalies. The most significant feature in anesthesia is the presence of severe mandibular hypoplasia. It is believed to be inherited as an autosomal recessive trait; however, an autosomal dominant pattern with variable expressivity cannot be eliminated due to the presence of similar features in the mother.

• Acro-Renal Syndrome: Characterized by unilateral renal agenesis, duplication of the collecting system, renal hypoplasia leading to renal insufficiency, and vesicoureteral reflux with hydronephrosis. The difference is the absence of digital abnormalities.

• ☞ADULT (Acro-Dermato-Ungual-Lacrimal-Tooth) Syn­drome: Characterized clinically with ectrodactyly, syndactyly, excessive freckling, lacrimal duct anomalies, dysplastic nails, hypodontia, hypoplastic breasts and nipples, hypotrichosis, hypohidrosis, broad nasal bridge, midfacial hypoplasia, exfoliative dermatitis, and xerosis. It is an autosomal dominant form of ectodermal dysplasia, a group of disorders that affects the hair, teeth, nails, sweat glands, and especially the hands and feet.

• ☞Ectrodactyly Ectodermal Dysplasia and Cleft Lip-Palate (EEC) Syndrome (Split Hand-Split Foot-Ectodermal Dysplasia-Cleft Syndrome): Belongs to an autosomal dominant form of ectodermal dysplasia that features a classical triad of ectrodactyly, ectodermal dysplasia, and facial clefts. Other characteristics include vesicoureteral reflux, recurrent urinary ...