Tricho-rhino-phalangeal syndrome type I

ARTICLE

The mother of an 8-year-old girl noticed that there was no need to cut her daughter's hair as she did in her other childern.

The previous medical history was unremarkable. Physical examination revealed a healthy girl of normal growth (height: 124 cm, weight: 26 kg) and intelligence. The hair was sparse and fine (Fig 1). The facial appearance is shown in Figures 1 and 2.

Routine laboratory examination were within the normal range.

Which diagnosis do you suggest? Which additional examinations do you propose?

Tricho-rhino-phalangeal syndrome type I

Another remarkable feature was a clino- and brachydactyly of fingers and toes (Fig. 3).

X-ray analysis of her hands showed cone-shaped epiphyses at the proximal interphalangeal joints and short phalanges (Fig. 4).

Tricho-rhino-phalangeal syndrome type I (TRPS I) is characterized by craniofacial and skeletal abnormalities. TRPS I patients have sparse, fine, slow growing scalp hair, a pear shaped nose and a high philtrum [1-7].

Giedion was the first to establish the entity of the trichorhinophalangeal syndrome, which is at present divided into four types on the basis of inheritance and other features like mental retardation and multiple cartilaginous exostoses. However, all of these phenotypes are thought to be part of a group of contiguous gene syndromes [2-4].

The inheritance is usually autosomal dominant. The gene that was recently assigned to chromosome 8q24 encodes a zinc-finger protein [5]. In our case, the patient may represent a new mutation of an autosomal dominant trait, because there are no other affected family members.

Other genetic diseases with associated hair defects such as the Larsen syndrome, the oral-facial-digital syndrome and the cartilage hair hypoplasia of the McKusick type should be distinguished from TRPS [1, 3].

TRPS I is not simply an aesthetic problem. The most frequently associated abnormality is the Perthes-like disease of the hips, necessitating orthopedic treatment and supervision [7].

References

1. Carrington PR, Chen H, Altick JA. Tricho-rhino-phalangeal syndrome, type I. J Am Acad Dermatol 1994; 31: 331.

2. Buhler EM, Buhler UK, Beutler C, Fessler R. A final word on tricho-rhino-phalangeal syndromes. Clin Genet 1987; 31: 273.

3. Boni R, Boni RH, Tsambaos D, Trueb RM. Trichorhinophalangeal syndrome. Dermatology 1995; 190: 152-5.

4. Happle R. Genetic defects involving the hair. In: Hair and Hair Diseases. Berlin. Springer 1990: 325-62.

5. Momeni P, Glockner G, Schmidt O, von Holtum D, Albrecht B, Gillessen-Kaesbach G, Hennekam R, Meinecke P, Zabel B, Rosenthal A, Horsthemke B, Ludecke HJ. Mutations in a new gene, encoding a zinc- finger protein, cause tricho-rhino-phalangeal syndrome type I. Nature Genet 2000; 24: 71-4.

6. Yanez S, Hernandez-Vicente I, Armijo M. Trichorhinophalangeal syndrome. Int J Dermatol 1992; 31: 706-9.

7. Minguella I, Ubierna M, Escola J, Roca A, Prats J, Pintos-Morell G. Trichorhinophalangeal syndrome, type I, with avascular necrosis of the femoral head. Acta Paediatr 1993; 82: 329-30.