Aplasia cutis congenita

[mawjood]

Hi,gues ....

I see today new thing in our NICU,so I read about it and I like to share this with you....

Aplasia cutis congenita (ACC) is a group of heterogeneous diseases characterized by congenital focal absence of the skin. It is most often limited to a solitary midline posterior scalp lesion, but other presentations include several smaller defects or involvement of the extremities or trunk. Clinical subtypes are characterized by their location and pattern of lesions, associated malformations, and mode of inheritance.

Erosions are present at birth. Unlike other blistering disorders, ACC involves both epidermis and dermis. A typical lesion is a sharply demarcated ulcerated plaque or patch that may be covered by a tense epidermal membrane, giving the appearance of a fluid-filled bulla. The lesions reepithelialize over several months, resulting in a hypertrophic or atrophic scar. The differential diagnosis includes other neonatal blistering conditions, such as EB, and lesions secondary to perinatal trauma, including scalp blood sampling, fetal monitoring electrodes, and forceps.

ACC is usually an isolated condition. However, other malformations may be associated. These include trisomy 13 or 4p- syndrome, cleft lip and palate, and defects of the hands and feet. A subtype characterized by a ring of long dark hair surrounding a congenital scalp lesion (hair collar sign), may indicate an associated cranial neural tube defect such as an encephalocoele, meningocele, or heterotopic brain tissue. One proposed mechanism is that this may arise from an abnormality of separation of the epithelial and neural ectoderm at the time of neural tube closure.

The etiology of ACC is uncertain, but it may result from a failure of ectodermal fusion during embryogenesis. This is supported by the observation that aplasia cutis of the face, which usually has a bilateral and preauricular location, appears to result from incomplete fusion of the ectodermal groove between the maxillary and mandibular facial prominences