Dyskeratosis Congenita: Definition, Etiology, Clinical features, Differential diagnosis, Treatment
Dyskeratosis congenita or Zinsser–Engman–Cole syndrome or Hereditary benign intraepithelial dyskeratosis (HBID) is a rare autosomal-dominant trait, most cases of which have been traced to a single ancestor.
- It is probably inherited as a recessive autosomal and X-linked trait.
Clinical features : It is characterized by –
- atrophic skin areas,
- nail dystrophy,
- skin and mucosal bullae,
- blepharitis and ectropion,
- oral manifestations
- The oral lesions consist of recurrent blisters, epithelial atrophy, and leukoplakia Squamous-cell carcinoma may occur.
The syndrome primarily affects oral and conjunctival mucosa. The oral mucosa is affected throughout, with the exception of the dorsum of the tongue, and develops wide areas of soft, spongy white lesions resembling clinical leukoplakia. The buccal mucosal lesions are the most prominent and will often extend onto the commissure. As the individual matures, the lesions increase in area and often become folded and variegated in appearance between white and a translucent mucosal color.
The conjunctival lesions are superficial, foamy, gelatinous plaques of the bulbar conjunctiva (ie, the conjunctiva covering the globe) that form just outward from the limbus (the junction of the cornea and bulbar conjunctiva). These plaques are associated with a conjunctival hyperemia, as noted by an increased number and size of vessels, not a true conjunctivitis as has been reported. There is no true inflammation. Some patients will develop photophobia. In rare cases, these plaques can cover the cornea and cause blindness as the plaques exfoliate and scar the cornea.
The epithelium is thickened by acanthosis and intracellular edema. The dyskeratotic cells are large, waxy-appearing eosinophilic cells in the upper portions of the epithelium. Basal cells and deep prickle cells are normal, as is the underlying connective tissue.
Ultrastructurally, the eosinophilic cells contain large numbers of tonofilaments and degenerated nuclei, and there is a loss of desmosomes.
- lichen planus
- epidermolysis bullosa
- pachyonychia congenita
- Jadassohn-Lewandowsky syndrome
- Jackson-Lawler syndrome
No specific treatment is necessary. On rare occasions, conjunctival plaques that threaten the cornea may need to be removed. Reassurance to family and individuals that the lesions are not premalignant and will not transform into a malignancy is recommended.