The main symptom of brown yellows arthritis is that the skin, sclera and cornea of the whole body are pigmented with brownish yellow color, the ear, nose and cartilage can turn blue, the edge of the tympanic membrane is grayish black, and the hearing is often reduced. Brownish yellow disease is due to the lack of uronic acid oxidase, so that phenylalanine, tyrosine intermediate metabolites (uronic acid) can not be further oxidation decomposition, accumulation in the body. The skin, sclera, and cartilage become darker, while urea causes hyperpigmentation of cartilage and other connective tissues and degenerative arthritis of the spine and peripheral large joints. On the other hand, urinary black acid is excreted in urine, where it is alkalized and oxidized to make the urine darker, so it is also called black aciduria. This disease is a rare genetic disease and is rare. The prevalence is reported abroad as 3 to 5 cases per million population. Because uric black acid is easily deposited in cartilage, it degenerates joints. The disease is often seen clinically as arthrosis, so it is called brown yellowness arthropathy. What are the tests for ear, nose and cartilage turning blue? 1.Urine black acid examination Urine becomes black after resting or alkalinization, and becomes brown after adding spot’s reagent. 2.X-ray examination (1) spine changes. Significant posterior protrusion of the thoracic spine and hyperflexion of the lumbar spine. Spine osteoporosis, advanced vertebral body edge with bone spur formation. There is extensive degenerative degeneration of the intervertebral disc with laminar calcification and a special flat thin oval double transverse calcified shadow with increased density, parallel to each other and with a translucent layer at the interval. The intervertebral disc involvement is extensive, especially at the lumbar spine. The intervertebral space is significantly narrowed. (2) Degenerative changes may occur in the shoulder and knee joints, and there may be calcification of tendon ligaments and narrowing of the sacroiliac joint with subarticular osteosclerosis. Calcification of the cartilage at the pubic symphysis also occurs, and there is subchondral bone erosion. Calcification may also occur in the tendons and periarticular soft tissues attached to the femoral head, acetabulum, greater trochanter, lesser trochanter, and sciatic tuberosity. 3.Special examination of urinary black acid The urinary black acid can be measured by spectrophotometer, and the urinary black acid content in blood and urine can also be measured by special enzymes. The main symptoms of this disease are brownish-yellow pigmentation of the skin, sclera and cornea of the whole body, the ear, nose and cartilage may turn blue, the edge of the tympanic membrane is grayish-black, and the hearing is often reduced. If uric acid is deposited on the aortic and mitral valves, the valves become stiff and murmurs appear. In men, the disease is often combined with black prostate stones. Bone and joint changes usually erode the spine first, followed by the knee, shoulder and hip. The incidence of spondylitis is 10% to 15%, more in men than in women. The patient complains of lumbar pain, examination of the lumbar plate, loss of anterior convexity, mild hunchback deformity, and posture similar to ankylosing spondylitis.