What Is Dyskeratosis Congenita?

Congenital dyskeratosis (DKC) is characterized by skin manifestations and can develop into a multisystem damage-linked genetic syndrome with bone marrow aplasia or tumor. Its genetic pattern is complex, including X-linked recessive, autosomal dominant and autosomal recessive three forms. Onset from childhood 2 to 3 years old, almost all patients with X-linked recessive DKC are male. The disease has three characteristics: malnutrition of nails cannot form a deck; the oral or vaginal mucosa may have white thickening; the skin may have extensive reticular pigmentation, especially in light-exposed areas. Clinically, symptomatic treatment is the main, and the prognosis is poor.

Basic Information

English name

DKC

Visiting department

dermatology

Whether inherited

Yes

Multiple people

All patients are male and develop onset in childhood 2 to 3 years old.

Causes of Congenital Poor Keratosis

The onset of congenital keratosis is related to mutations in genes encoding keratin protein (DKC1 gene), RNA component gene encoding telomerase (TERC gene), and reverse transcriptase gene encoding telomerase (TERT gene). . The inheritance methods include X-linked recessive inheritance, autosomal dominant inheritance and autosomal recessive inheritance.

Clinical manifestations of congenital keratosis

1. A malnutrition

Patients with malnutrition can develop from 5 to 13 years of age, atrophy and thinning, sharpening, bending and shedding. It may have white spots, or it may become a horny plug or be completely destroyed. Purulent paronychia can occur repeatedly. In mild cases, nail folds or fissures can be seen.

2. Skin symptoms

The skin may have atrophy and pigmentation. Patients generally have pigmented changes 2 to 3 years after birth, and develop to complete form 3 to 5 years later. Fine reticular gray-brown pigmentation can be seen in the upper part of the trunk, neck, face, and abdomen, which can also affect most of the trunk. Skin atrophy and telangiectasia are very significant; facial skin is red and atrophic, with irregular spot-like pigmentation; the back of hands, feet, and feet are widely atrophied, transparent and shiny, palms and palms can be thickened and sweaty. Bullous can form after trauma.

3. Mucosal damage

Mucosal damage occurs simultaneously with or after nail damage. Tongue and oral mucosa can appear vesicles and erosions, followed by irregular erythema, white spots, but sometimes also extensively spread to wart-like thickening, and also gingivitis. The ocular conjunctiva may also have similar changes or scarring, which can cause nasolacrimal duct obstruction and excessive tearing. The esophagus can become narrowed or have diverticulum, making swallowing difficult. White spots in the rectum, anus, and urethra can cause narrowing. Similar changes can be seen throughout the mucosa of the gastrointestinal tract or urogenital organs.

4. Other

See also aplastic anemia, skeletal abnormalities, mental retardation, and splenomegaly.

Congenital keratosis examination

Blood routine

Blood routine can find patients with reduced whole blood cells.

2. Skin tissue pathology

The epidermis of congenital keratosis becomes thinner, the epidermal mutation flattens or disappears, the melanin in the basal layer of some skin increases, and melanocytes appear in the superficial dermis.

3. Gene mutation analysis

At present, 9 kinds of gene mutations have been identified as related to congenital keratosis, and if a disease-causing gene is found in a genetic test, the diagnosis can be clearly confirmed.

Diagnosis of congenital keratosis

1. Onset in childhood, more common in boys.

2. Frequently affects the chest, back, neck, face, limbs, and mucous membranes.

3. Signs

(1) skin damage: yellow-brown, gray spots, mixed with loss or pigmentation, or fine mesh or network, there are capillary dilation and atrophy.

(2) A: Malnutrition, atrophy and thinness, sharp or twisted, lighter ones have ridges and grooves.

(3) Mucosa: white spots on the mucous membranes such as the cheeks, anus, and urethra, which can be wart-like thickened.

(4) Others: mental retardation, hypersplenism, aplastic anemia, bullous conjunctivitis, gingival disease, esophageal stricture or diverticulum, skeletal abnormalities, palm sweats, etc. Malignant lesions are prone to occur on the skin, mouth, rectum, and cervix.

4. Laboratory inspection

Genetic testing finds a mutation in a causative gene that can be diagnosed.

Differential diagnosis of congenital keratosis

Vasotrophic skin heterochromia

The disease is free of nail defects and mucosal leukoplakia. Pathological examination shows that the superficial dermis capillaries are dilated and densely infiltrated with lymphocytes.

2. Congenital skin heterochromia

It mostly occurs in girls. Although there is a change in skin color, it has light sensitivity, juvenile cataracts, congenital bone defects, and no fingernails and mucosal damage.

3. Anhidrotic ectodermal dysplasia

There are teeth changes, a distinctly special look, and little or no hair, but nail changes are rare.

Complications of congenital keratosis

Bone marrow failure, malignancy, lung fibrosis, etc.

Treatment of congenital keratosis

There is no effective cure for this disease, and symptomatic treatment is mainly adopted to prevent and treat complications.

1. Locally complete excision or physical therapy such as electrocoagulation, laser, and freezing can be performed on the limited white spots to avoid malignant changes.

2. Aplastic anemia can be treated with testosterone, glucocorticoids, colony-stimulating factors, hematopoietic stem cell transplantation and other methods.

Poor prognosis of congenital keratosis

The prognosis of this disease is poor, it can develop into blood disease or cancer and cause death. Only patients with malnutrition and pigmentation have a good prognosis.