Lipidosis: causes, symptoms, diagnosis, treatment

Lipidosis refers to accumulation diseases (thesaurismosis), almost always occur with CNS damage, so they are called neyrolipidoses. Skin manifestations are one of the main symptoms only in the diffuse Fabri angiokeratome (glycosphingolipidosis), with other forms they occur infrequently, probably because of an early lethal outcome.

Glycocerebrosidosis (Gaucher's disease) is a disease that is based on a decrease in the activity of beta-glucosidase, glycocerebrosides accumulate in macrophages (Gaucher cells) of the spleen, bone marrow, lymph nodes, liver, lungs, endocrine glands, brain neurons and intramural autonomic ganglia. The disease is inherited by autosomal recessive type. There are three clinical options: I - chronic, II - acute neuropathic (juvenile). III - chronic neuropathic, which are probably due to different mutations. The main symptoms are hepatosplenomegaly, cerebral dysfunction with convulsions, mental retardation, bone damage. In the skin there may be focal or diffuse pigmentation, mainly of the open parts of the body, with splenomegaly - petechiae and ecchymosis. Histologically, an increase in the content of melanin in the epidermis is detected, sometimes in the upper part of the dermis.

The Niemann-Pick disease is characterized by the accumulation of sphingomyelin phospholipid in neurons and glial cells of the brain and elements of the macrophage-histiocytic system of internal organs. The disease is caused by a defect in sphingomyelinase activity, inherited by an autosomal recessive type. Skin due to an increase in the content of melanin yellowish brown, can be observed xanthomas. Histologically, in some cases, the amount of pigment in the epidermis increases and individual xantom cells in the dermis are determined.

Angiokeratoma of the body diffuse (Anderson-Fabry disease) is due to the insufficiency of alpha-galactosidase. W. Epinette et al. (1973) associate it with a decrease in the activity of a-L-fucosidase. The cases of Fabry disease with normal activity of the enzyme are described, which indicates a genetic heterogeneity of the disease. It is inherited recessively, linked to the X chromosome. The clinical manifestations are the deposition of lipids in endotheliocytes and pericytes of blood vessels, smooth muscle cells, ganglion cells, nerves, corneal epithelium, kidneys, and skin. The defeat of the skin is characterized by the appearance in childhood or adolescence of numerous small red (1-2 mm in diameter) dark red angiokera, mainly on the lower part of the body, genitals, thighs, buttocks, almost exclusively in men. In heterozygous women, there may be changes in the kidneys and eyes, very rarely the skin. The prognosis is unfavorable, since in middle age (40 years) renal failure, myocardial infarction or stroke develop.

Pathomorphology. There is a sharp expansion of the capillaries of the papillary layer of the skin, the walls of which are formed by a single layer of endotheliocytes, surrounded by loose strands of connective tissue. The epidermal processes and hair follicles undergo pressure atrophy. The enlarged and blood-filled capillaries sometimes closely adjoin each other, forming multi-chamber cavities, between which one can see long narrow epidermal outgrowths.

The upper part undergoes atrophy, sometimes there is a slight vacuolization of the cells of the basal layer of the epidermis. Hyperkeratosis is often very strong, with the phenomena of parakeratosis, especially when the capillaries are affected not only by the papillary, but also the mesh layers of the dermis. Lipids are detected using specific methods of staining.

Special fixation of skin biopsies is necessary in 1% calcium chloride solution with addition of 10% formalin or preparations contain 10% formalin for 2 days, then in 3% potassium dichromate solution for up to 1 week. After fixation, stain by the Tarnovsky method. Lipids are well detected by the black-shaded Sudan and sharlough. They are birefringent, therefore visible in a polarizing microscope.

Lipids are found not only in angiomatologically altered vessels, but also in clinically unchanged skin, in fibroblasts, muscles, lifting hair. Lipid deposition is detected by electron microscopy in endothelial cells, pericytes, fibroblasts inside large lysosomes as two kinds of intracellular inclusions surrounded by a two-loop membrane and having a lamellar structure. Lysosomes consist of alternating electron-dense and light bands. In most of them, the activity of phosphatases is detected, and in the residual bodies, myelin structures are found.

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