Kronos is a rare disease in which due to the violation of protein metabolism in the cartilage, ligaments and tendons, less often in other connective tissue formations (the sclera, skin, heart valves and others), is postponed agronomicheskaya pigment, dye these tissues in the dark (from smoky-grey to black).
The first clinical symptom of Ahronoth - alkaptonuria - the appearance of dark-brown or black color of urine. Kronos is endogenous (hereditary, family) and exogenous (in case of poisoning by carbolic acid, resorcinol). The first is more common in men, from 30 to 50 years.
When distributed ohaneze the skin of patients becomes grayish-brown color, nails, slate, with brown stripes; patients complain of a feeling of rigor Mortis in the sacrolumbar - region, constant pain and inability fully to bend and straighten the spine. Affected eardrum (reduction hearing) and cartilages of the larynx (severe shortness of breath). On the radiograph reveals the porosity of cartilage. With limited ohaneze affects large joints - the knee, the shoulder, the hip.
The diagnosis is based on laboratory analysis of urine (many homogentisic acid).
The forecast. Mild forms can be cured completely, far stalled the process is irreversible. The treatment is performed by a physician; designate large doses of vitamin C (1000 - 3000 mg / day) and cytochrome (up to 30 mg / day), prednisone, alkeran.

Kronos (ochronosis; from the Greek. ochros - pale yellow and nosos - disease - disease of the cartilage and other entities (ligaments, tendons, sclera, endocardium, Dura and others), characterized by their colouring in smoky-gray or light brown up to brown color, pain syndrome and alkaptonuria.
The etiology and pathogenesis of Ahronoth not yet known. It is about the violation of interstitial exchange of aromatic amino acids tyrosine and phenylalanine - due to the lack of the enzyme (homogentisate), capable to split homogentisic acid contained in the serum of healthy people. The first manifestation of Ahronoth is alkaptonuria, that is dark-brown and even black color of urine, containing a large number homogenizing (2,5-dioxygenases) acid. This acid is a normal intermediate in the oxidation process phenylalanine and tyrosine. Under the influence of the enzyme tyrosinase it turns into agronomicheskaya, melaninogenica pigment, the structure of which is still unknown. Ability homogentisic acid to join in connection with chondromalacia explain elective color cartilage when kroese. Special tropism of the pigment to the cartilage tissue, probably due to the reduced level of currency and a slowdown of oxidative processes in it. Pigmentation of the cartilage can be obtained and experimentally when immersed in a solution of homogentisic acid.
Kronos is endogenous (alkaptonuria, congenital, hereditary, often family) and exogenous (the result of poisoning by carbolic acid, resorcinol).
Pathological anatomy. When ohaneze observed pigmentation intervertebral, sternoclavicular cartilage, incontrato pelvic bone, cartilage of the ear, nose, trachea, bronchi. The hue and intensity of this color is different from smoky-grey to inky black. Coverage cartilage diffuse, accompanied by fragility, porosity, razvlecheniem and their deposition in them lime. Neravnomernosti colour is observed in the tendons, fascia, ligaments, and joint surfaces. The last look as if eaten. Non-permanent pigmentation noted in the kidneys (often with black agronomicheskaya the concrements in the pelvis), the aorta (especially clear in atherosclerosis in the form of black edging environmental plaques, and black spots in the areas of calcification), in the meninges. In the heart of the pigment is deposited in endo - and the pericardium, cardiosclerosis scars, valves, especially when they sclerosis. In severe forms of the disease pigmentation captures the adrenal glands, thyroid, testicular and ovarian, pancreatic, and prostate cancer, smooth and striated muscles. As an exception, Kronos may occur in the spleen.
Microscopically in cartilaginous tissue is determined by the abundance of pigment straw-yellow color, which is located both within the cartilage cells, and in the interstitial substance cartilage. Last looks loaded fine drops, the intensity of accumulation which runs parallel to the destruction of cartilage cells. In articular cartilage when ohaneze not observed neoplasms of the cartilage tissue, and pronounced destructive processes in the form of dry cartilage with the formation of a kind of spear or crystal-like clumps, pathognomonic for agronomicheskaja (alkaptonuria) of osteoarthritis.
The clinical picture. Kronos is more common in men than in women. The most affected age from 30 to 50 years. Clinically there are two forms of O. - common and limited. When common form of O. skin grayish-brown color, especially in the areas well lit. In the armpits skin blue-green color. Nails are hard, brittle, bluish tint, with brown stripes in distal departments. On the face around the eye) is often dotted black pigmentation, sclera of the eye pigmented. In auricles are determined dark-brown, sometimes violet seen through the skin bumps dense consistence. In the ear sulphur contained homogenizing acid. Eardrum with dark brown spots. Hearing patients decreases, frequent Cathars of the auditory tube with a decrease in hearing high tones, noise and false auditory sensation. The first clinical symptoms of cartilaginous tissue of the spine: the feeling in the sacrolumbar region, which the patients described as a sense of rigor Mortis, increasing pain, which becomes a permanent, impossibility of full extension and low mobility of the spine at bending. Radiograph shows fixation of the thoracic and lumbar spine straightening his physiological
bending. At advanced stages of the process in the intervertebral cartilage is delayed lime, enshrining the stillness of a backbone with the porosity of the vertebral bodies. From small cartilage special clinical significance belongs to the cartilages of the larynx, which fix the vocal cords in the middle position, that causes severe shortness of breath patient.
To a limited form of Ahronoth include joint lesions are often the knee, then the shoulder, the hip. The small joints, as a rule, are not affected. Joint develops a picture of deforming arthritis, subsequently giving the picture of the frets. In addition to joint injury, to a limited is Acting kidney damage with the picture agronomicheskaja nephrosis, may result in a secondary puckering of the kidneys.
Diagnosis of Ahronoth is made on the basis of external examination of the patient and laboratory analysis of urine. Sometimes when laryngo - and traheostomii you can see the black color of the cartilage, which in mild skin manifestations may suggest about Acting
The treatment should be aimed at lowering alkaptonuria. 4-methyl-2-thiouracil causes disease remission. Therapeutic effect of vitamin C (up to 1000-3000 mg per day) due to termination of formation of pigment, thus a possibility prevention agronomicheskaya arthropathy in patients suffering from alkaptonuria. ACTH, cortisol and prednisone slow down the disease. Normalizes the color of cartilage cytochrome that take up to 50 mg per day.
The use of alkiona based on its ability to inhibit the oxidation of tyrosine and subsequent reduction education homogentisic acid.
The forecast. During the process chronic. Reversible forms can be completely cured.
In cases of advanced process the prognosis is poor.