gout nodules
Introduction
Introduction Gout nodules are characteristic features of gout and are formed by the accumulation of urate crystals. It can occur in any tissue other than the central nervous system, but is more common in soft tissues around the joints, including tendons and ligaments, especially the distal extremities and the outer ear cartilage, which are less common elsewhere.
Cause
Cause
Cause:
The long-term increase of uric acid in the blood is the key cause of gout. Human uric acid mainly comes from two aspects:
(1) Nucleic acids and other terpenoids produced by protein catabolism in human cells produce endogenous uric acid by the action of some enzymes.
(2) Indole compounds, nucleic acids and nuclear protein components contained in food. After digestion and absorption, exogenous uric acid is produced by the action of some enzymes.
The formation of uric acid is a very complicated process and requires the participation of some enzymes. These enzymes can be roughly divided into two categories: enzymes that promote uric acid synthesis, mainly 5-phosphate nucleic acid-1-pyrophosphate synthase, adenine phosphate nucleoside Acid transferase, phosphoribosyl pyrophosphate amide transferase and xanthine oxidase; enzymes that inhibit uric acid synthesis, mainly hypoxanthine-guanosine transferase, gout is caused by various factors, such as the activity of these enzymes, such as The activity of promoting uric acid synthase is enhanced to inhibit the decrease in the activity of uric acid synthase. As a result, excessive production of uric acid or obstruction of uric acid in the kidney due to various factors causes uric acid to accumulate in the blood, resulting in hyperuricemia.
If hyperuricemia exists for a long time, uric acid will deposit in the form of urate in joints, subcutaneous tissues and kidneys, causing a series of clinical manifestations such as arthritis, subcutaneous gout stones, kidney stones or gouty nephropathy. The disease is recurrent acute or chronic arthritis of the peripheral joint, which is caused by deposition of monosodium urate crystals in the supersaturated hyperuricemia body fluid in and around the joints and tendons.
Examine
an examination
Related inspection
Leucine uric acid polarized light microscopy urinary leucine uric acid
Diagnosis: There is no uniform standard for the diagnosis of gout in China. The American College of Rheumatology Standard American Holmes Standard and the Japanese Revised Standard are used to introduce the American College of Rheumatology classification criteria for acute gouty arthritis (1977):
1. The specific urate crystals were found in the synovial fluid;
2. Gout stone is confirmed by chemical method or polarized light microscopy to contain sodium urate crystal;
3. With the following clinical laboratory and X-ray signs, 6 of 12 items
(1) more than one episode of acute arthritis;
(2) Inflammation showed a peak within 1d;
(3) single arthritis episodes;
(4) The skin of the affected joint is dark red;
(5) pain or swelling of the first ankle joint;
(6) unilateral seizure involving the first metatarsophalangeal joint;
(7) unilateral seizure involving the tibial joint;
(8) There is a suspicious tophi;
(9) hyperuricemia;
(10) X-ray shows joint asymmetry swelling;
(11) X-ray film shows that the subcortical cyst is not accompanied by qualitative erosion;
(12) The microbial culture of joint fluid is negative during the onset of joint inflammation;
When the diagnosis of acute arthritis is difficult, you can try colchicine for diagnostic treatment. If it is gout, the symptoms will be relieved quickly after taking colchicine, which is of diagnostic significance.
In short, acute gout is not difficult to diagnose according to typical clinical manifestations, laboratory tests and treatment response. The diagnosis of chronic gouty arthritis needs to be carefully identified, and urate crystals should be obtained as much as possible.
Diagnosis
Differential diagnosis
Differential diagnosis:
(1) Differential diagnosis in the acute phase
1. Acute rheumatoid arthritis: history of infection with group A hemolytic streptococcus before the disease mainly affects the heart and joints. The following characteristics can be identified: 1 more common in adolescents; 2 often hemolytic before 1 to 4 weeks before onset Streptococcal infection such as pharyngeal tonsillitis; 3 often invaded the knee and shoulder elbow and other joints and has migratory symmetry; 4 often accompanied by myocarditis ring erythema and subcutaneous nodules; 5 anti-hemolytic streptococcus antibodies such as ASO>500U anti-streptokinase>80U anti-hyaluronidase>128U; 6 salicylic acid preparation is effective; 7 blood uric acid content is normal.
2. Pseudo-gout: The deposition of calcium pyrophosphate in articular cartilage is particularly similar to that of gout in type A acute sexual assault but has the following characteristics: 1 more common in the elderly; 2 lesions mainly invading the large joints such as the knee shoulder and hip; 3X line radiographs showed narrowing of joint space and cartilage calcification showed dense point or linear boneless destruction; 4 serum uric acid content was normal; 5 calcium pyrophosphate monoclinic or slant crystal can be found in synovial fluid; 6 colchicine treatment effect is poor.
3. Suppurative arthritis: The main points identified by Staphylococcus aureus are: 1 can detect primary infection or suppurative lesions; 2 more major joints such as hip and knee joints with high heat chills and other symptoms; 3 joint cavity Puncture fluid for smear exudate smear microscopic examination showed Gram-positive staphylococci and cultured Staphylococcus aureus; 4 no urate crystals in synovial fluid; 5 anti-foreign drug treatment was ineffective.
4. Traumatic arthritis: 1 has a history of joint trauma; 2 affected joints have no migration; 3 no urate crystals in synovial fluid; 4 serum uric acid is not high.
5. Gonorrhea arthritis: Acute attack of the toe joint is similar to gout, but it has the following characteristics: 1 has a history of smelting or gonorrhea; 2 can be found in synovial fluid can be found in diarrhea or bacterial culture positive without uric acid crystal; 3 penicillin The efficacy of G and ciprofloxacin can be identified.
(2) Differential diagnosis of chronic phase
1. Chronic rheumatoid arthritis: This disease is often chronic. About 10% of cases have subcutaneous nodules near the joints, which is easily confused with atypical gout. However, the disease: 1 finger toe small joints often symmetrical prismatic swelling, and unilateral asymmetry of gout arthritis; 2X line shows that the articular surface is rough, joint space is narrow, sometimes part of the articular surface fusion bone Generally loose but no cortical defect changes; 3 active rheumatoid factor-positive joint fluid without urate crystallography.
2. Psoriasis arthritis: This disease is also common in men, often asymmetrically invading the distal toe joint, and 0.5 patients with elevated blood uric acid content, it is necessary to identify with gout. The main points are as follows: (1) Most patients with joint lesions occur after psoriasis; 2 lesions often invade the distal end of the toe joint, more than half of the patients with nail thickening and depression into a ridge-shaped bulge; 3X line image can be seen severe joint destruction joint space Widening of the bone at the end of the toe is shortened and the bone is absorbed and shortened. The symptoms of the joints are alleviated as the skin lesions improve or worsen with the deterioration of the skin lesions.
3. Tuberculosis allergic arthritis: caused by allergic reaction caused by Mycobacterium tuberculosis infection 1 often involves the small joints gradually affecting the large joints, and has multiple, migratory features; 2 patients with active tuberculosis lesions; Have a history of acute arthritis; can also only show chronic joint pain, but no joint stiffness and torso; 4 joints around the skin often have nodular erythema; 5X line shows osteoporosis, no cortical defect changes; 6 slip The liquid showed more monocytes, but no urate crystals; 7 tuberculin test was strongly positive, and anti-spasm treatment was effective.
