dystrophy

, dystrophia1. any of various bodily disorders, characterized by wasting of tissues 2. Ecology a condition of lake water when it is too acidic and poor in oxygen to support life, resulting from excessive humus content

Dystrophy

degeneration, a pathological process arising from metabolic disturbances and characterized by the appearance in the tissues of altered metabolic products (quantitatively and qualitatively).

Dystrophy is a process that lies at the basis of the development of numerous diseases. Among its mechanisms of development are infiltration, or impregnation (for example, infiltration by protein of the epithelium of the renal tubules in nephroses, lipoid infiltration of the inner wall of the arteries in atherosclerosis); distorted synthesis (for example, synthesis of hemomelanin in malaria); conversion (of fats and carbohydrates into proteins, or of proteins and carbohydrates into fats); and decomposition, or phanerosis (decomposition of the lipoproteins of the cell membranes; for example, of the elastic fibers of the aorta in syphilitic mesaortitis). The dystrophies include disorders of blood and lymph circulation or innervation, hypoxia, infections, intoxications, disruptions of the hormonal (endocrine disorders) and enzymal (enzymopathies) balance, and other metabolic disturbances. Protein, fat, carbohydrate, and mineral dystrophies are distinguished, depending on the predominant type of metabolic disturbance. The morphological manifestations of impaired metabolism can be found either within the cells or outside them, or evenly in both the cells and the intercellular substance. Dystrophies can be thus classified as cellular, noncellular, and mixed. Dystrophies may be either general (systemic) or local.

The development of protein dystrophies, or dysproteinoses, is connected with the entry of pathological proteins into the cells or the intercellular substance, with distorted protein synthesis, or with the disintegration of tissue structures; in this case the protein changes both physicochemically and morphologically. The cellular dysproteinoses include granular, or parenchymatous (changes in the functional tissue of the liver, kidneys, and muscle fibers of the heart); hyalin-drop (formation of hyalin within the cells in the form of spheres or drops), dropsical (appearance of droplets of fluid in the cytoplasm or nucleus, leading to the disintegration of the cell), and horny. The noncellular dystrophies include mucoid swelling, fibrinoid changes (deposit of a heterogeneous substance called fibrinoid, in whose formation all elements of the connective tissue and blood proteins take part, and noted in allergic conditions, collagenoses, and certain infectious diseases), hyalinosis, and amyloidosis. The mixed dysproteinoses include a large number of dystrophies that occur with the disruption of the metabolism of chromoproteins (hemosiderosis, melanosis, hemomelanosis, jaundices, and porphyrias), nucleoproteins (gout, uratic inspissation), and glycoproteins (mucous and colloidal dystrophies). Mucous dystrophy develops in the epithelium and connective tissues. The epithelial cells begin to produce a mucus-like substance (mucoid) and mucous (mucin) at an intensified rate, then die and are cast off; the condition is noted during inflammation of the mucous membranes. In the connective tissue it is most marked with tumors (chondromas, myxomas, and others). Colloid dystrophy develops in the glands (thyroid and pituitary); it is characterized by excess production of colloid and resultant distension of the follicles, death of the cells, and impregnation of the glandular tissue by the colloid.

Fat dystrophies, or lipidoses, are characterized by a change in the amount of fat in the fat storage cells, the appearance of lipids in places where they do not usually occur, and a change in the quantity and quality of lipids in the cells and tissues. Disruption of the metabolism of neutral fat is manifested in a decrease or increase in its reserves and may be general or local. A general decrease in the amount of fatty tissue is typical of emaciation (cachexia), while local decrease is typical of regional lipodystrophy (lipoatrophy), or atrophy of the fatty tissue of particular areas of the body. A special form is progressive lipodystrophy—Barraquer’s and Simmonds’ diseases—which is expressed by the disappearance of fat in the head, neck, and thorax. A general increase in fat reserves leads to obesity, while a local increase is observed with the atrophy of functional tissue or an organ (fat substitution) and in Dercum’s disease—the development of fat deposits in diffuse form or in the form of separate nodes (lipomas). Disruption of the metabolism of the lipoids (phosphatides) of the cytoplasm (cellular lipoidoses) is most often encountered in the parenchymatous organs (myocardium, liver, and kidneys); less frequently, it is characterized by the deposit of various types of lipoids (system lipoidoses) in the reticular-endothelial system: cerebroside and kerasin in Gaucher’s disease, lecithin in Niemann-Pick disease, cholesterol in Hand-Schüller-Christian disease. Noncellular fat dystrophy (noncellular lipoidosis) of the blood vessels is the basis of atherosclerosis.

The carbohydrate dystrophies involve disruption of the metabolism of polysaccharides, mucopolysaccharides, and glycoproteins. The disruption of glycogen metabolism is most important. These conditions are most clearly marked in diabetes mellitus, where tissue reserves of glycogens are sharply decreased, and in glycogenoses—Gierke’s disease and others—during which glycogen is deposited in excessive amounts in the liver, heart, kidneys, and skeletal muscles.

Among the mineral dystrophies, the most important are disturbances in the metabolism of potassium, calcium, iron, and copper. An increase in the amount of potassium in the blood and tissues is noted in Addison’s disease. A deficiency of potassium explains the occurrence of the hereditary disease periodic paralysis (familial myoplegia, paroxysmal paralysis—characterized by sudden attacks of flaccid paralysis of the skeletal muscles). Disruptions of calcium metabolism—calcareous dystrophies, or tissue decal-cifications—are characterized by the precipitation of calcium in the tissues in the form of dense masses. A distinction is made between metastatic (calcareous metastases), dystrophic (petrification), and metabolic (calcareous gout, calcinosis) tissue decalcification. In calcareous metastases, which are associated with hypercalcemia (increased calcium content in the blood), widespread decalcification of organs and tissues (lungs, stomach, kidneys, heart, and arteries) is observed; in dystrophic decalcification the calcium is deposited in tissues that are in a state of necrobiosis, or necrotic. Metabolic decalcification may be general or local. Iron is contained mainly in hemoglobin; disruptions of its metabolism are linked with hemoglobinogenic pigments (chromoproteins) and are expressed by hemosiderosis (deposit of the pigment hemosiderin in the skin as dark brown spots, as well as in internal organs) and hemochromatosis (melanodermia, pigment cyrrhosis, bronzed diabetes-characterized by the deposit of the pigments hemosiderin, hemofuscin, and melanin in the liver, pancreas, lymph nodes, myocardium, and elsewhere; simultaneous with the precipitation of pigment, the functional tissue is replaced by connective tissue). Hepatocerebral dystrophy, in which copper is deposited in the liver, kidneys, brain, and cornea, is a disease of impaired copper metabolism.

The mechanisms of development of dystrophy are studied with the methods of histochemistry, electron microscopy, autoradiography, and histospectrography.

REFERENCES

Serov, V. V. Distrofiia. In A. I. Strukov, Patologicheskaia anatomiia. Moscow, 1967.
Davydovskii, I. V. Obshchaia patologiia cheloveka, 2nd ed. Moscow, 1969.

V. V. SEROV

dystrophy

[′dis·trə·fē] (medicine) Defective nutrition. Defective or abnormal development or degeneration.

dystrophy

[dis´trah-fe] any disorder due to defective or faulty nutrition, especially muscular dystrophy. adj., adj dystroph´ic.adiposogenital dystrophy adiposity of the feminine type, genital hypoplasia, changes in secondary sex characters, and metabolic disturbances; seen with lesions of the hypothalamus; see also adiposogenital dystrophy.Becker's muscular dystrophy (Becker type muscular dystrophy) a form closely resembling Duchenne's muscular dystrophy, but having a later onset and milder course; transmitted as an X-linked recessive trait.distal muscular dystrophy distal myopathy.Duchenne's muscular dystrophy (Duchenne type muscular dystrophy) The childhood type of muscular dystrophy.facioscapulohumeral muscular dystrophy muscular dystrophy affecting the face, shoulder, and upper arm muscles; called also Landouzy-Dejerine muscular dystrophy.Landouzy-Dejerine dystrophy (Landouzy-Dejerine muscular dystrophy) facioscapulohumeral muscular dystrophy.muscular dystrophy see muscular dystrophy.myotonic dystrophy a rare, slowly progressive, hereditary disease, marked by myotonia followed by muscular atrophy (especially of the face and neck), cataracts, hypogonadism, frontal balding, and cardiac disorders. Called also dystrophia myotonica, myotonia atrophica, and myotonia dystrophica.progressive muscular dystrophy muscular dystrophy.pseudohypertrophic muscular dystrophy muscular dystrophy affecting the shoulder and pelvic girdles, beginning in childhood and marked by increasing weakness, pseudohypertrophy of the muscles, followed by atrophy, and a peculiar swaying gait with the legs kept wide apart. Called also pseudohypertrophic muscular paralysis.reflex sympathetic dystrophy a syndrome of chronic pain that usually develops after a trauma or noxious stimulus, although the nerve injury cannot be immediately identified. The pain is not limited to the distribution of a single nerve and is often out of proportion to the precipitating event. It is most often described as a burning pain, and is accompanied by swelling, sweating, sensitivity to touch, and sometimes changes in tissue growth. Called also chronic or complex regional pain syndrome. Clinical practice guidelines have been published by the Reflex Sympathetic Dystrophy Syndrome Association of America and are available on their web site at http://www.rsds.org or by writing to Reflex Sympathetic Dystrophy Syndrome Association of America, P.O. Box 502, Milford CT 06460.

dys·tro·phy

(dis'trō-fē), Progressive changes that may result from defective nutrition of a tissue or organ. Synonym(s): dystrophia [dys- + G. trophē, nourishment]

dystrophy

(dĭs′trə-fē) also

dystrophia

(dĭ-strō′fē-ə)n.1. Any of various unrelated, noninfectious, often genetic disorders characterized by progressive deterioration or structural alteration of a body part.2. A degenerative disorder caused by inadequate or defective nutrition. No longer in scientific use.

dystrophy

Medtalk Partial atrophy of tissue or an organ attributed to ↓ nutrition. See Becker's muscular dystrophy, Benign pseudohypertrophic muscular dystrophy, Hyperplastic dystrophy, Lattice dystrophy, Map-dot dystrophy, Myotonic dystrophy, Neuroaxonal dystrophy, Reflex sympathetic dystrophy, Spider dystrophy, Third dystrophy, Twenty nail dystrophy. Cf Atrophy.

dys·tro·phy

(dis'trŏ-fē) Abnormal development or growth of a tissue or organ, usually resulting from nutritional deficiency.
Synonym(s): dystrophia. [dys- + G. trophē, nourishment]

dystrophy

A vague term applied to conditions in which tissues fail to grow normally, or to maintain their normal, healthy, functioning state. See CORNEAL DYSTROPHY and MUSCULAR DYSTROPHY.

dystrophy

A non-inflammatory developmental, nutritional or metabolic disorder.
adult vitelliform foveomacular dystrophy See pattern dystrophy.
anterior membrane dystrophy See Cogan's microcystic epithelial dystrophy.
band-shaped corneal dystrophy See band keratopathy.
Best's vitelliform macular dystrophy See Best's disease.
bleb-like dystrophy See Cogan's microcystic epithelial dystrophy.
central areolar choroidal dystrophy An autosomal dominant dystrophy of the macula with onset in the third to fifth decades of life. It causes a progressive decrease in visual acuity. It is characterized by bilateral, atrophic macular lesions, between one and three disc diameters in size and through which choroidal vessels can be seen. The prognosis of this condition is poor as it is progressive. Syn. central aerolar choroidal sclerosis. See choroideremia.
central crystalline dystrophy An autosomal dominant stromal corneal dystrophy. Yellow-white crystals are scattered throughout the central cornea. Since the lesions are usually found below Bowman's layer, the corneal epithelium remains unaffected. The crystals consist of cholesterol and fats. They do not affect vision.
Cogan's microcystic epithelial dystrophy A bilateral corneal dystrophy located in the corneal epithelium and occurring most commonly in females. It is characterized by variously shaped greyish-white microcysts and debris, which vary in shape and location over time, coalescing with other microcysts, forming lines, and resembling a fingerprint pattern. Symptoms are minimal and vision is unaffected unless the lesions are in the central zone of the cornea. The condition may be associated with recurrent epithelial erosions, which cause pain, lacrimation, photophobia and blurred vision. Management normally includes artificial tears, patching and antibiotics and occasionally therapeutic soft contact lenses for frequent or more severe types. Syn. anterior membrane dystrophy; bleb-like dystrophy; epithelial basement membrane dystrophy; fingerprint dystrophy. See recurrent corneal erosion.
cone dystrophy A degeneration of the cone photoreceptors which, in most cases, is inherited in an autosomal dominant or X-linked recessive fashion, but some cases are sporadic. It appears in the first or second decades of life and is characterized by a progressive loss of visual acuity, colour vision impairment, photophobia and central scotoma. Ophthalmoscopic examination may show a demarcated circular atrophic area in the macular region (bull's eye maculopathy). There is no known treatment. Syn. cone degeneration. See achromatopsia; monochromat.
cone-rod dystrophy A bilateral degeneration of the photoreceptors affecting the cones first and the rods later. It may be inherited in an autosomal dominant fashion caused by mutations in the retinal guanylate cyclase gene (GUCY2D) or X-linked recessive fashion but many cases are sporadic. It appears in the first to third decades of life. It is characterized by poor visual acuity, colour vision impairment and photoaversion to bright sunlight. The ocular fundus may eventually show an atrophy of the retinal pigment epithelium, which appears as a bull's eye maculopathy. Eventually as the rods degenerate there is progressive night blindness. There is no known treatment.
congenital hereditary endothelial dystrophy (CHED) A hereditary type of corneal dystrophy occurring in either an autosomal dominant or autosomal recessive form. The autosomal dominant form presents during the first year or two of life causing pain, corneal oedema, tearing, and photophobia with slowly progressive corneal opacification. This form does not cause nystagmus since normal corneal function is present during the early period of visual development. The autosomal recessive form presents earlier, usually at birth, and consists of a significantly thickened corneal stroma (oedema) with nystagmus. There is no tearing or photophobia noted. This dystrophy appears to be due to an abnormality in endothelial cell development during the early second trimester of gestation, but does not appear to be related to any other systemic or ocular abnormality.
corneal dystrophy Hereditary disorders affecting both corneas. It is occasionally present at birth but, more frequently, it develops during adolescence and progresses slowly throughout life. It varies in appearance and is often described on that basis (e.g. band-shaped corneal dystrophy), or on the basis of which layer is affected. Dystrophies affecting the anterior part of the cornea include Cogan's microcystic epithelial dystrophy, Meesmann's dystrophy and Reis-Buckler dystrophy. Stromal dystrophies include central crystalline dystrophy, granular dystrophy, lattice dystrophy, macular corneal dystrophy, and posterior corneal dystrophies include cornea guttata, congenital hereditary endothelial dystrophy, Fuch's endothelial dystrophy and posterior polymorphous dystrophy.
corneal dystrophy of Bowman's layer type 1 See Reis-Buckler dystrophy.
fingerprint dystrophy See Cogan's microcystic epithelial dystrophy.
Fuchs' endothelial dystrophy A progressive dystrophy of the corneal endothelium seen more commonly in women than in men, usually in the fifth decade of life. It may be transmitted in an autosomal dominant fashion. It is characterized by wart-like deposits on the endothelial surface. As the condition progresses, there is oedema of the stroma and eventually of the epithelium and bullous keratopathy causing blurring of vision and pain. The stroma may also become vascularized. It is often associated with glaucoma and nuclear lens opacity. Treatment includes hypertonic agents (e.g. sodium chloride 5%), a bandage soft contact lens and in severe cases penetrating keratoplasty. See cornea guttata; bullous keratopathy.
granular dystrophy A hereditary condition characterized by the presence of irregularly shaped white granules of hyaline in the stroma of the cornea surrounded by clear areas. It is caused by mutation in the keratoepithelin gene (TGFBI). It usually develops during the first decade of life and progresses slowly throughout life. It rarely results in loss of vision although the granules are located in the centre of the cornea. If severe, though, a corneal graft is the main treatment. Syn. corneal granular dystrophy; Groenouw's type 1 corneal dystrophy.
Grayson-Wilbrant dystrophy See Reis-Buckler dystrophy.
Groenouw's type 1 corneal dystrophy; type 2 corneal dystrophy See granular dystrophy; macular corneal dystrophy.
juvenile vitelliform macular dystrophy See Best's disease.
lattice dystrophy An autosomal dominant, hereditary disorder characterized by the appearance in the corneal stroma of fine branching filaments interlacing and overlapping at different levels, as well as white spots and stellate opacities. These filaments are deposits of amyloid. The onset usually begins in the first decade of life and progresses in the following decades. Recurrent corneal erosions are common. When visual acuity becomes impaired, keratoplasty may be necessary. Syn. Biber-Haab-Dimmer corneal dystrophy; lattice corneal dystrophy type I.
macular dystrophy A group of inherited disorders involving the macular area due to defective metabolism or nutrition in the sensory layer of the retina (e.g. cone dystrophy, cone-rod dystrophy), the retinal pigment epithelium (e.g. Best's disease, Stargardt's disease and pattern dystrophy), or the choroid (e.g. central areolar choroidal dystrophy).
macular corneal dystrophy An autosomal recessive disorder characterized by bilateral, grey-white nodules, which progressively develop into a generalized opacification of the corneal stroma. It is caused by mutations in the gene for a specific sulfotransferase gene (CHST6) and depending on the presence or absence of keratan sulfate in the serum and cornea the condition is divided into type 1 and type 2, but they are clinically indistinguishable. By about the fifth decade of life visual acuity is markedly diminished and penetrating keratoplasty may be necessary. Histological examination shows an accumulation of mucopolysaccharide in the stroma and degeneration of Bowman's layer. Syn. Groenouw's type 2 corneal dystrophy.
Meesmann's dystrophy A dominant, hereditary, bilateral disorder characterized by numerous small punctate opacities in the corneal epithelium. It is caused by mutations in the genes encoding the cornea-specific keratins K3 (KRT3) and K12 (KRT12). The condition appears in infancy. It is usually asymptomatic but in some cases there is discomfort and a slight decrease in visual acuity. In severe cases, keratoplasty may be necessary. Syn. juvenile epithelial corneal dystrophy; hereditary epithelial dystrophy.
myotonic dystrophy An autosomal dominant hereditary disease characterized by progressive weakness and atrophy of skeletal muscles with delayed muscle relaxation. The main ocular manifestations are cataracts with multicoloured crystals, small dot opacities in the cortex and subcapsular region of the lens, ptosis and pupillary abnormalities. Syn. Steinert's disease.
pattern dystrophy A group of inherited macular disorders characterized by bilateral yellow or black pigment deposits at the level of the retinal pigment epithelium (RPE) forming a variety of patterns such as butterfly wings (butterfly dystrophy), or spider-shaped (reticular dystrophy), or round slightly elevated (adult vitelliform foveomacular dystrophy, which resembles Best's disease but has its onset in the fourth to sixth decades and with only a slight decrease in vision). Pattern dystrophies have been linked to mutations in the peripherin/RDS gene in some patients. The peripherin protein, which is normally present in the photoreceptor outer segments, is disrupted and eventually interferes with RPE metabolism. There may be a slight reduction in visual acuity and mild metamorphopsia, although many patients are asymptomatic. The electrooculogram may show a reduced Arden ratio.
posterior polymorphous dystrophy An autosomal dominant, usually bilateral, dystrophy of the endothelium and Descemet's membrane appearing either at birth or in early childhood. It is caused by mutation in the visual system homeobox gene (VSX1). The disease is characterized by polymorphous plaques of calcium crystals and vesicular lesions in the endothelium and on its surface. It is usually asymptomatic, but in some cases corneal oedema occurs and it may require penetrating keratoplasty.
retinal dystrophy See macular dystrophy; retinitis pigmentosa.
Reis-Buckler dystrophy An autosomal dominant disorder of the cornea characterized by ring-shaped opacities occurring at the level of Bowman's layer and protruding into the epithelium. It is caused by mutation in keratoepithelin gene (TGFBI). The opacities increase in density with time giving rise to a honeycomb appearance. The condition begins in childhood and progresses with frequent recurrent corneal erosions resulting in scarring, decreased visual acuity and reduced corneal sensitivity. In severe cases, keratoplasty may be necessary. Syn. corneal dystrophy of Bowman's layer type 1. A similar condition is Grayson-Wilbrant dystrophy in which visual acuity is less affected, corneal erosions are less frequent and corneal sensitivity is normal.
Stargardt's macular dystrophy See Stargardt's disease.
vitelliform macular dystrophy See Best's disease.

dys·tro·phy

, dystrophia (dis'trŏ-fē, dis-trōfē-ă) Progressive changes that may result from defective nutrition of a tissue or organ. [dys- + G. trophē, nourishment]

Patient discussion about dystrophy

Q. Anyone have/hear of RSD (Reflex Sympathetic Dystrophy) CRPS etc ,I have Fibro too Reflex Synmpathetic Dystrophy or CRPS and I have Fibromyalgia any others with CNS problemsA. Ok I would like to ask if any others with RSD would like to get to know each other it looks like they have groups ,no one without RSD can appreciate the pain and the way those who you love the most ,think you are a faker because some RSDers ,you can't see anything readily ,not being believed with Nerve pain thayt is worse than anything I have felt like being shot ,blown up ,Third Degree Burns well kinda like when the nerves stgart to grow back from Third degree burns but 24/7 and the same degree of p[ain since 1968 .IF RSD IS CAUGHT IN THE FIIRST YEAR IT CAN BE Reversed so yes I want knowledge (oops didnt mean caps(to yell)Thank You rsdno

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dystrophy

dys·tro·phy

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dystrophia

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dystrophy, dystrophia

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Dystrophy

REFERENCES

dystrophy

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Patient discussion about dystrophy

dystrophy

Synonyms for dystrophy

noun any of several hereditary diseases of the muscular system characterized by weakness and wasting of skeletal muscles

Synonyms

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noun any degenerative disorder resulting from inadequate or faulty nutrition

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