Edition 60 - 2016, September / Images

Images in Pediatric Endocrinology: EVALUATION OF A GIRL WITH CORPORAL DISPROPORTION – Ed. 60

Mariana del Pino, Maria Alejandra Arenas y Virginia Fano.

Servicio de Crecimiento y Desarrollo. Hospital de Pediatría Juan. P Garrahan, Buenos Aires, Argentina

im60

Figure: X-ray film of hand and right forearm in a 10-year, 8-month-old girl  : 1) Triangularization of the distal radial epiphysis  2) pyramidalization of the distal carpal row  3) lucency of the distal ulnar border of the radius 4) Short  and bend radial bone. Left: attenuated but similar findings
Clinical Case
A 10-year- and 8-month old girl, from interior of the country was admitted because of body disproportion and genu varum.
She was born by normal delivery, after a gestational age of 38 weeks; birth weight was 3000 grams (-0.45 SDS), body length: 49 cm (-0.16 SDS), and head circumference 35 cm (0.05 sDS).

Neurologic development and schooling were normal.

Family history: Healthy mother with short stature, 144.2 cm (-2.77sDS), and a history of short stature in her father’s family. Father, 33 years old, healthy, height 173.3 cm (0.08 sDS).
Six months prior to admission, his pediatrician noticed short limbs. The following studies were performed: blood count, calcium and phosphorus metabolism, thyroid function, blood sugar, serum BP3 and IGF1, all normal, as well as a 46,XX karyotype.
Parents decided to travel to Buenos Aires for further studies.

Physical examination:
No facial dimorphism was observed. Mesomelic slight shortening of upper and lower limbs was found. No limitation in supination was detected. She had a genu varum, with a intermalleolar distance of 1.5 cm. Sexual development was prepubertal: Breasts 1, pubic hair 1 (Tanner).

Anthropometry:
Decimal age: 10.66 years
Weight 45.3 kg (90/97 centile) (1.58 sDS)
Height 133.1 cm (10/25 centile) (-0.82 SDS)
Sitting Height 76.6 cm. Sitting height/height index was 0.57 (3 sDS) (del Pino et al, 2016, sent to publication). Head circumference 54.0 cm (1 sDS). Body Mass Index: 25.57 (2.3 sDS).

Suspicion of a skeletal dysplasia in a girl with body disproportion, but normal height, was considered.

Radiography.

A skeletal radiographic study was then ordered. An X-ray film (Figure) showed bilateral and asymmetric compromise of forearm, hand and wrist, more intense on the right side, as described in the figure.

After evaluation of family history of short stature, clinical findings of body disproportions and radiological signs, the diagnosis of a skeletal dysplasia was made, probably secondary to SHOX gene alteration.

Comments:
The evaluation of body proportions, the  sitting height/body height index, as well as the ratio of the length of the limbs or head circumference (PC) to height, is of great importance in the clinical evaluation of a child,  since the discovery of body disproportion in the presence, or  not, of short stature, suggests an underlying skeletal disease.
Skeletal dysplasias are rare genetic diseases (3.2 in 10,000 newborns in South America) that affect bone and cartilage tissue; its presentation can be detected at different ages. In some skeletal dysplasias, clinical-radiological diagnosis is made in the neonatal period, but sometimes it takes a long term to diagnose them, even up to the end of the growth period. SHOX gene alteration was suspected in this patient.
The diagnosis of SHOX gene alterations are usually made on the base of clinical-radiological signs, whose development is dependent on age. They encompass a group of skeletal diseases, with a wide variability of expression, ranging from idiopathic short stature to a very severe phenotype. They include de following:
1) Langer mesomelic dysplasia (MIM # 249700), caused by anomalies in both alleles of the SHOX gene, with homozygosity or compound heterozygosity. It presents with severe stunting, heights between -6.02 and -9.0 sDSs, and body disproportions because of skeletal abnormalities.
2) Leri-Weill Dyschondrosteosis (MIM # 127300), which has a less severe phenotype caused by SHOX gene haploinsufficiency due to an alteration in one of the alleles. They are characterized by mild to moderate body disproportions and Madelung deformity (the latter caused by  shortening and bowing of the radius and ulna leading to dorsal displacement of the distal ulna, as well as limited mobility of the wrist and elbow).
Both, short statue and skeletal abnormalities, are expressed independently, and can be the only manifestation of the altered gene SHOX. It can occur as short stature with disproportion but very subtle radiological signs (such as the X-ray of the forearm and hand of the left side of our patient) or in a patient with normal stature and disproportion with radiological signs.
3) The 3rd group includes children with “idiopathic short stature” (MIM 312865) 2%, i. e., short stature but no clinical or radiological signs. In this case an asymmetry of radiological signs in the presence of normal height for the argentine population, or within the family genetic range but with body disproportions might be observed. The evaluation of parents is suggested when one or both are short for the population, as they may be carriers of some conditions. On the other hand, when there is suspicion of alterations in the SHOX gene, bilateral radiographs of hand and forearm, in the antero-posterior incidence and with palms up, should be ordered.

References:

  1. Rappold G, Blum WF, Shavrikova EP, Crowe BJ, Roeth R, Quigley CA, Ross JL, Niesler B. (2007) Genotypes and phenotypes in children with short stature: clinical indicators of SHOX haploinsufficiency. J Med Genet. 44(5):306-132.
  2. Binder G, Ranke MB, Martin DD. (2003) Auxology is a valuable instrument for the clinical diagnosis of SHOX haploinsufficiency in school-age children with unexplained short stature. J Clin Endocrinol Metab. 88(10):4891-6.3.
  3. Binder G, Renz A, Martinez A, Keselman A, Hesse V, Riedl SW, Häusler G,Fricke-Otto S, Frisch H, Heinrich JJ, Ranke MB. (2004) SHOX haploinsufficiency and Leri-Weill dyschondrosteosis: prevalence and growth failure in relation to mutation, sex, and degree of wrist deformity. J Clin Endocrinol Metab. 89(9):4403-8.
  4. Lejarraga H, del Pino M, Fano V, Caino S, Cole TJ. (2009). Growth references for weight and height for Argentinian girls and boys from birth to maturity: incorporation of data from the World Health Organisation from birth to 2 years and calculation of new percentiles and LMS values. Arch Argent Pediatr. 107(2):126-33.
  5. V Fano, Displasia esqueléticas ¿cuándo pensar, cómo estudiar? Medicina Infantil, 2013  Vol XX(2): 146-152

Posted in Edition 60 - 2016, September, Images
Previous Editions
Images
Instructivo para mandar imágenes
CLICK AQUI
RSS Feed