Tricho-Rhino-Phalangeal Dysplasia Type III

At a glance

An extremely rare inherited multisystem disorder characterized by fine, thin light-colored hair, unusual facial features, abnormalities of the fingers and/or toes, and multiple abnormalities of epiphyses leading to skeletal dysplasia. The skeletal dysplasia is mostly observed in the hands and feet. There are no exostoses. Normal intelligence. Severe end of TRPS spectrum.

Synonyms

TRPS III; Sugio-Kajii Syndrome.

Incidence

Extremely rare. Both sexes affected equally. However, of the reported cases, most affected individuals have been female. Approximately 15 cases have been reported in the medical literature.

Genetic inheritance

Trichorhinophalangeal Syndrome Type III is suggested as an autosomal dominant genetic transmission.

Pathophysiology

There is evidence suggesting that Type III TRPS is caused by mutation in the TRPS I gene, which is also the site of mutation in Type I TRPS.

Diagnosis

This syndrome is characteristically identified by the presence of sparse and thin hair, a beaked nose, long upper lip, and severe metacarpophalangeal shortening visible clinically and confirmed radiologically (eg, severe shortening of metacarpals, metatarsals, and phalanges) and the abnormal development of the epiphyses of the phalangeal bones (epiphyseal coning). It is different than the Ruvalcaba Syndrome by the absence of mental retardation and microcephaly.

Clinical aspects

This medical condition is characterized by fine, brittled, thin light-colored hair, a beaked nose, and severe brachydactyly. Infants affected with this condition may exhibit several characteristic facial features, including a pear-shaped or rounded nose, hypoplastic alae nasi, an abnormally long, broad philtrum on the upper lip, a protruding upper lip, malar hypoplasia, and/or an abnormally prominent maxilla. Dental anomalies are also considered a frequent occurrence in this syndrome (eg, malocclusion). The abnormalities of the hands and feet include brachydactyly because of an incomplete development of the metacarpals, metatarsals, and phalanges. Most affected individuals exhibit a clinodactyly (permanent fixation of the fingers). Short stature, osteochondritis, thoracic scoliosis, pectus carinatum, and/or limited movements of certain joints complete the clinical presentation.

Precautions before anesthesia

Assessment of severity of syndrome and previous skeletal problems. Limitation in the range of motion in the hips and various joints must be evaluated. Proper assessment of the upper airway structures must be obtained because of potential limitation during direct laryngoscopy. The severity of the pectus carinatum must be assessed clinically and with chest radiograph if needed. The potential for chronic use of corticosteroids should be considered and assessed prior to surgery.

Anesthetic considerations

Careful positioning and padding must be considered because of the tendency to severe limitation in the range of motion. Unless there is limitation in the maxillomandibular joint and difficult direct laryngoscopy and tracheal intubation expected, ...