Congenital ichthyosiform erythroderma of Brocq is one of the forms of congenital ichthyosiform erythroderma, a distinctive feature of which is the predominance of hyperkeratosis phenomena over other clinical symptoms, the absence of rashes on the mucous membranes. The primary elements are erythematous spots with a tendency to peripheral growth, with hyperkeratotic layers or small vesicles. The decisive moment in the diagnosis is the family history and clinic, as a confirmation, a histological examination is carried out. Symptomatic treatment – moisturizing and softening of the skin, periodic courses of vitamin A, corticosteroids.
Congenital ichthyosiform erythroderma of Brocq is a rare type of universal hyperkeratosis that occurs from the moment of birth. The disease was first described by French dermatologist Louis Brock in 1902. Extensive practical experience and a significant number of clinical observations gave the scientist the opportunity to be the first to describe a number of dermatoses known today under his name: Brock’s pseudopelada, Brock’s lupoid sycosis, Brock’s congenital ichthyosiform erythroderma. For the characteristic appearance of the skin in congenital ichthyosiform erythroderma, the researcher aptly called the pathology “fish scale disease”. The nuances that formed the basis for the differentiation of clinical manifestations of ichthyosis belong, among others, to L. Brock. Due to the rarity of skin pathology, data on endemicity and prevalence are unknown. Dermatosis has no racial, age, gender components. The disease is of practical interest to specialists in the field of genetics and dermatology.
The causes of congenital ichthyosiform erythroderma of Brocq are associated with hereditary, genetic pathology caused by different levels of damage to the genetic apparatus and clinically manifested in different components of the dermis. With congenital ichthyosiform erythroderma, Broca’s suffers primarily from the epidermis. Its thickness, the work of the glandular apparatus of the skin, pigmentation are determined by the characteristics of the human genotype. Genes control the production of proteins and the activity of enzyme processes. The “incorrect” work of enzymes is reflected in the clinic of the disease.
A skin condition in which the formation of dry, dead dermis cells prevails in certain areas of the skin or on its entire surface is associated with the type of inheritance: autosomal dominant (congenital bullous ichthyosiform erythroderma) or autosomal recessive (congenital nebulous ichthyosiform erythroderma). The bullous form is caused by mutations in genes located on chromosomes 12 and 17 and encoding the synthesis of keratin 1 and 10; the non-bullous form occurs when the epidermal transglutaminase gene is mutated, localized on chromosome 14q11. The severity of clinical manifestations and the prognosis of the disease depends on the type of inherited mutations. The dominant type of inheritance is characterized by a milder course and a favorable prognosis, recessive – on the contrary. The patterns leading to mutations have not been fully studied. Consanguinity of parents increases the risk of disease in children.
The autosomal dominant type of inheritance always gives 50% of healthy heirs, 50% of patients. With an autosomal recessive type of inheritance of dermatosis, options are possible. If both parents are not sick, but are carriers of pathology, then 25% of their children will definitely get sick; 25% will be healthy, and 50% will inherit the carrier. If one of the parents is sick and the other is a carrier, then the probability of the disease is 50%. If both parents are sick, there are no healthy birth options. If a sick child is born to healthy parents, this is a new spontaneous mutation of the gene.
Clinically, congenital ichthyosiform erythroderma of Brocq is divided into two variants: bullous (with the formation of blisters) and nebulous (“dry”). Broca’s nebulous congenital erythroderma is characterized by a bright diffuse congenital erythema, dense to the touch, against which there is abundant peeling in the form of hyperkeratotic, translucent brown scales capable of separating in whole layers. In addition to dryness, there is a feeling of tightness of the skin.
With a mild degree of dermatosis, only the face, palms and soles are involved in the process. The heavy current captures the entire skin completely. The child cannot breathe normally, suck, open his mouth. Sweat glands do not work well, so heat or the slightest physical exertion leads to a rise in temperature to 40 degrees. Moisture is lost through cracks in the epidermis, dehydration occurs. Often such changes end in death. If the baby survives, then the skin pathology persists for life. Over time, hair loss joins the skin manifestations, up to complete baldness; the work of the sweat apocrine glands is disrupted. The skin becomes dense and in the area of the lips, ears, eyelids leads to deformations (inversions of the skin).
A distinctive feature of congenital bullous ichthyosiform erythroderma is the appearance of blisters and elements of epidermis detachment against the background of erythematous altered skin immediately after birth. The skin is swollen, thickened. The mild degree of the disease is characterized by single primary elements with horny scales, independent resolution of the process by 3-5 years. In severe cases, blisters cover the entire skin, open, forming areas of wetness, creating a risk of secondary infection, and transform into hyperkeratotic crusts.
If the process is localized in the folds of the skin, on the extensor elbow surfaces, in the popliteal pits, armpits, warty growths of a soft consistency form, firmly adjacent to the dermis, forming a pattern resembling corduroy. “Warts” smell unpleasant. Sometimes the bubbles pour out only on the palms and soles, merge with each other, open, become covered with keratin scales, resolve, leaving behind a small pigmentation. A process resembling seborrhea “smoulders” on the scalp, the hair is preserved, the nails are dull and thickened. With age, the pathological process tends to improve.
The disease is diagnosed on the basis of anamnesis, clinic and genetic testing. Histologically, in the “dry” variant, the granular layer of the epidermis is hypertrophied, inflammatory infiltrate, acanthosis is determined in the dermis. The bubble variant gives granular degeneration of the cells of the Malpighian layer. Congenital ichthyosiform erythroderma of Brocq is differentiated with all varieties of true ichthyosis based on histological examination. Additionally, back-seeding of blood, separated bladders is carried out in order to exclude sepsis, secondary infection.
Treatment of congenital ichthyosiform erythroderma of Brocq
There is no pathogenetic treatment. Taking into account the severity of the process, newborns are placed in the intensive care unit, maintaining high humidity and controlling dehydration, signs of secondary infection. In the first days, a dermatologist and a geneticist are consulted. Baths are shown, followed by moisturizing the skin with emollient creams (baby cream). The shock agent of the main therapy is retinoids (vitamin A, its synthetic analogues). They are taken in courses, according to individual schemes, in large dosages. Periodically, a complete clinical and diagnostic examination is carried out in order to monitor the functional state of the liver, kidneys, and heart muscle. With bullous form, resistance to vitamin A group drugs has been noted, in this case, corticosteroids are connected to treatment. Vitamin therapy is recommended. Baths with bran, starch, sea salt give a good effect. Externally, emollient, corticosteroid ointments are applied with the addition of 3% salicylic acid in a ratio of 1:1.
Prognosis and prevention
Living with skin affected by congenital ichthyosiform erythroderma of Brocq is difficult, especially for children. Sometimes patients need the support of a psychologist. Constant dispensary monitoring of the patient with annual anti-relapse therapy is necessary. During periods of remission – daily, long-term use of skin softening creams. The prognosis depends on the severity of the pathology, the timeliness of the treatment started. Possible fatal outcome.
Since congenital ichthyosiform erythroderma of Brocq is a rare genetic dermatosis, prenatal medical and genetic examination of married couples with a burdened hereditary history, subsequent consultation of a geneticist, and making an informed decision about childbirth are necessary for preventive purposes when planning pregnancy. If pathology is detected during pregnancy, its termination is indicated.