Showing posts with label Pediatrics. Show all posts
Showing posts with label Pediatrics. Show all posts

20080911

Achondrogenesis

The term achondrogenesis is actually a misnomer, as it implies that cartilage is not made. In this condition, cartilage is made but it is profoundly abnormal. A more correct term would be chondrogenesis imperfecta.

The term achondrogenesis refers to a diverse group of generally lethal chondrodysplasias characterized by a short trunk, severe micromelia, and a disproportionately large cranium. Achondrogenesis is the second most common lethal short-limb dysplasia.

Ectopia Cordis

Thoracoabdominal ectopia cordis is better known as the pentalogy of Cantrell and is in part a misnomer, given that the heart is not truly ectopic.

In pentalogy of Cantrell the heart is abnormally sited with the apex oriented down, but is positioned within the chest and therefore not ectopia cordis. Both cervical and abdominal ectopia cordis may occur without a sternal cleft. Abdominal ectopia cordis does not belong in this group of anomalies because the defect is diaphragmatic and does not involve the thorax or the anterior abdominal wall.

Neonatal lupus erythematosus (NLE)

Neonatal lupus erythematosus (NLE) is a misnomer, as these newborns do not have systemic lupus erythematosus, but a constellation of clinical disorders associated with, and probably in part caused by, autoantibodies that are passively acquired by the fetus transplacentally.

The majority of newborns with NLE exhibit cutaneous or cardiac disease, among other symptoms.

Adenoma Sebaceum

Adenoma sebaceum is a misnomer because these growths are angiofibromas rather than tumors of the sebaceous gland tumors.

Adenoma sebaceum is the most commonly recognized cutaneous marker of tuberous sclerosis; the lesions appear on the face during middle to late childhood or adolescence in approximately 80% of patients. These red-brown or flesh-colored, smooth, glistening, telangiectatic 1–10?mm papules may extend from the nasolabial folds to the cheeks and chin.

Aniridia

The term aniridia is a misnomer because iris tissue is usually present, although it is hypoplastic.

Two thirds of the cases are dominantly transmitted with a high degree of penetrance. The other one third of cases are sporadic and are considered to be new mutations. The condition is bilateral in 98% of all patients regardless of the means of transmission and is found in approximately 1/50,000 persons.


Aniridia is a panocular disorder and should not be thought of as an isolated iris defect. Macular and optic nerve hypoplasia are commonly present and lead to decreased vision and sensory nystagmus. The visual acuity is measured as 20/200 in most patients, although the vision may occasionally be better. Other ocular deformities are common and may involve the lens and cornea. The cornea may be small, and a cellular infiltrate (pannus) occasionally develops in the superficial layers of the peripheral cornea. Clinically this appears as a gray opacification. Lens abnormalities include cataract formation and partial or total lens dislocation. Glaucoma develops in as many as 75% of individuals with aniridia.

One fifth of sporadic aniridic patients may develop Wilms tumor.Of particular interest is the association of aniridia, genitourinary anomalies, mental retardation, and a partial deletion of the short arm of chromosome 11. Among individuals thus affected, the appearance of Wilms tumor is more common. It is thought that only patients with sporadic aniridia are at risk for developing Wilms tumor, although Wilms tumor has occurred in a patient with familial aniridia. Wilms tumor usually presents before the 3rd yr. Therefore, these children should be screened using renal ultrasonography every 3–6 mo, until approximately age 5 yr of age.