Other crystal arthropathy
Introduction
Introduction to other crystalline arthropathy In recent years, in addition to sodium urate, calcium pyrophosphate and alkaline calcium phosphate crystals, other types of crystal deposition have been found in pathological specimens or joint fluids, including oxalates, lipid crystals, protein crystals and the like. Some of them can also cause symptoms similar to arthritis, some have potential pathogenicity, and some even have not found the corresponding disease. basic knowledge Sickness ratio: 0.0001% Susceptible people: no specific population Mode of infection: non-infectious Complications: cardiomyopathy anemia
Cause
Other causes of crystalline arthropathy
(1) Causes of the disease
Clinically discovered or suspected that a new crystal is associated with a group of clinical symptoms, there will be a corresponding basic research to identify the chemical composition of the crystal, spatial structure and its possible pathogenesis, and has now established a relatively complete In vitro research methods and animal models of crystalline arthropathy, for example, crystals are often injected into the joint cavity of the rat, intrapleural cavity or intraperitoneal cavity, locally creating a microenvironment similar to synovial inflammation to study crystals and The relationship between inflammation, and the in vitro culture of cells together with crystals and some chemokines has once become fashionable. In these experiments, some crystals were found not to induce acute inflammation, but instead interacted with some chronic inflammatory cells. It has a long-lasting and inflammatory effect.
Oxalate crystal arthropathy
Renal failure is considered to be the initial cause of the disease. So far, the deposition of oxalate crystals has only been found in the joint fluid of patients with severe renal failure, and renal failure is considered to be the initial cause of the disease, sometimes even if it has been found There is crystal deposition in the joints or bone tissues. Clinicians are also more willing to diagnose the disease after the diagnosis of renal failure is established. Recently, the joints caused by rheumatoid arthritis caused by renal amyloidosis The deposition of internal oxalate crystals has also attracted people's attention. In addition, it has been reported that oxalate deposition can occur in patients after small bowel resection or some intestinal diseases, but the deposition site is not located in the joint, nor will it Leading lesions in the joints, 1990, Louthrenoo et al also reported a case of local occurrence of oxalate crystal deposition due to foot infection with Aspergillus niger, and recently found that vitamin C has the potential to accelerate the deposition of oxalate crystals, Because vitamin C can produce oxalic acid during metabolism in the body.
2. Iatrogenic arthritis caused by corticosteroid deposition
As early as 1951, when the joint application of glucocorticoids in the treatment of joint diseases including crystalline arthritis was started in the clinic, it was found that the symptoms of arthritis were often aggravated within a few hours after the injection. Or after a slight turn, it will relapse again.
3. Lipid crystal arthropathy At present, lipid is a controversial factor as a pathogenic factor of rheumatism, but it is indeed related to some clinical symptoms, such as cholesterol crystals involved in the formation of rheumatoid nodules, in some volunteers Subcutaneous injection of lipid crystals can also induce local inflammatory responses.
4. Protein crystal arthropathy IgG cryoprecipitate paraproteins and monoclonal immunoglobulins are deposited in the joints, or when other parts of the body are deposited, the deposition of these proteins in the joints can induce local inflammation, when vascular crystallization Can cause embolization of blood vessels.
5. Foreign body reaction The artificial joint material polymethyl methacrylate (PMlMA) and its derivatives, natural substances embedded in the human body, can indeed cause inflammatory reactions or foreign body reactions.
(two) pathogenesis
Basic research has broader implications for exploring the pathogenesis of cholesterol, lipid liquid crystals, and bilirubin. Some studies have shown that cholesterol deposition in the joint activates the complement system, a mechanism that may be in the vascular wall atheroma. The block formation and hardening process play a similar role. In addition, basic research is also instructive for finding and manufacturing artificial joint materials that are more wear-resistant and firmer, but have little rejection reaction with the body. Artificial joint materials that are often used at present. Polymethyl methacrylate (PMlMA) and its derivatives can cause inflammation in rats. At present, the physical properties and charge distribution of sodium urate crystal surface are studied thoroughly, and these two factors are obviously in sodium urate. Crystal-induced inflammatory responses play an important role, and if these properties are shared by other inflammatory crystals, they are of great significance for the treatment of crystalline arthropathy.
1. The deposition of oxalate crystals in the joint can lead to acute and chronic lesions of various joints. Deposition of oxalate crystals in other tissues can also lead to myocardial lesions or heart block, peripheral neuropathy and aplastic anemia. Subcutaneous deposition may present miliary nodules, and the exact pathogenesis and principles are not well understood.
2. Iatrogenic arthritis caused by corticosteroid deposition
Among the hormones selected, pyruvate triamcinolone acetonide is the most inflammatory, because in all hormones it is closest in size and structure to sodium urate and calcium pyrophosphate crystals, and its solubility It is also relatively small, making it more susceptible to deposition and leading to inflammation.
3. Lipid crystal arthropathy
In recent years, people have found the deposition of lipid liquid crystals in the joints of arthritis patients secondary to joint hemorrhage and joint trauma, called "liquid crystal", mainly due to the physical properties of lipids, in aqueous solutions. The medium lipid usually spontaneously aggregates into a microsphere shape which also has a lipid bimolecular structure, the latter exists both as a solid form and liquid fluidity, and red blood cell fragments in joint blood are considered to be lipid liquid crystal micro The main source of the ball, other sources include exudates of previous inflammation, etc. When the lipid liquid crystal microspheres in the synovial fluid reach a certain concentration and begin to be swallowed by phagocytic cells, they can cause symptoms of acute arthritis.
4. Protein crystal arthropathy
The mechanism is still not very clear. One patient with IgG cryoprecipitated paraprotein disease has a large amount of paraprotein deposited in the joint and is secondary to chronic erosive polyarthritis. There is a chronic inflammatory reaction around the deposited protein crystals. Proteins and monoclonal immunoglobulins are not only deposited in the joints, but also in other parts of the body. When these proteins crystallize in blood vessels, they can cause embolization of blood vessels.
5. Foreign body reaction
The artificial joint material polymethyl methacrylate (PMlMA) and its derivatives, which are often used at present, can cause inflammatory reactions in rats. Many foreign bodies that enter the joints due to trauma, especially puncture wounds, often enter the joints. Wrapped by synovial tissue and deposited on the wall of the joint cavity can cause acute and chronic inflammation of the joint.
Prevention
Other prevention of crystal joint disease
prevention
The incidence of renal osteopathy is concealed, and there are often no symptoms, blood calcium is lowered, and elevated blood phosphorus and alkaline phosphatase can be used as the basis for early diagnosis. Tibial biopsy, photon absorption bone mineral density measurement and 99ECT scan can make early diagnosis. Rate increase, diagnostic points:
1 diagnosis basis of renal failure;
2 children are rickets, adults are mainly bone pain, and the lower limbs bear heavy bones;
3X line examination showed specific bone disease performance.
Once renal osteopathy is discovered, the above preventive measures should be implemented immediately. Subtotal thyroidectomy should be performed for patients with obvious secondary hyperparathyroidism, persistent hypercalcemia, metastatic calcification and severe itchy skin. .
prevention
To avoid trauma, fractures and significant skeletal deformities, surgery can be considered to correct, but preoperative preparation should be sufficient, such as correcting the patient's anemia, nutritional status, etc., and do the intraoperative monitoring.
Complication
Other complications of crystalline joint disease Complications cardiomyopathy anemia
1. Oxalate crystal arthropathy. Patients treated with hemodialysis or peritoneal dialysis due to renal failure may have oxalate deposits in the intervertebral disc, often leading to destruction and degeneration of the intervertebral disc, and oxalate crystals in other tissues. Deposition within can also result in local necrosis due to insufficient blood supply, myocardial lesions or heart block, peripheral neuropathy, and aplastic anemia.
2. Protein Crystals Protein crystals can cause embolization of blood vessels when crystallized in blood vessels.
Symptom
Other symptoms of crystalline arthropathy Common symptoms Traumatic nodule block
Oxalate crystal arthropathy
The deposition of oxalate crystals in the joints can lead to acute and chronic lesions of various joints, most commonly involving the knee and hand joints, while other joints such as the wrist, ankle, foot and tendon sheath, and joint capsule lesions are also It has been reported that patients treated with hemodialysis or peritoneal dialysis for renal failure may also have oxalate deposits in the intervertebral disc, which often lead to destruction and degeneration of the intervertebral disc, deposition of oxalate crystals in other tissues. It can also lead to the following consequences: local necrosis due to insufficient blood supply, myocardial lesions or heart block, subgranular nodules, peripheral neuropathy and aplastic anemia.
2. iatrogenic arthritis caused by glucocorticoid deposition
Iatrogenic arthritis caused by glucocorticoid deposition, even in patients with osteoarthritis that are sensitive to topical treatment of hormones, it has now been found that the number of inflammatory cells in the synovial fluid increases in a short period of time after hormone injection. The phenomenon of enhanced phagocytosis, the inflammation caused by this hormone deposition is easily distinguished from the infection inflammation caused by local operation, the former often occurs within 8 hours after injection, while the latter takes 1 day or longer. Significant symptoms, joint inflammation caused by glucocorticoid deposition lasts for a short time, the symptoms can be gradually relieved with the dissolution of hormone particles, and the hormone released by dissolution itself can inhibit the further development of inflammation.
3. Lipid crystal arthritis
Clinically, single arthritis is often onset, knee joint is the most commonly involved joint, followed by wrist joint. Cases of polyarthritis are occasionally reported. The diagnosis of this disease requires joint fluid examination under polarized light microscope. The white blood cell count of the liquid is (10-40)×109/L, mainly neutrophils. The typical lipid liquid crystal microspheres have a diameter of about 2-20 m. One isometric arm can be found in the microsphere due to birefringence. Cross-shaped shadows, if there are only a small number of microspheres in the field of view, usually do not have much clinical significance, but if a large number of liquid crystal microspheres are found inside and outside the cell, further diagnosis can be given in combination with clinical symptoms.
Attempts have been made to explain the relationship between type II and type IV hyperlipoproteinemia and arthritis and tenosynovitis by lipid crystal deposition. Schumacher and Michael reported in 1989 that a patient with hypercholesterolemia complicated with Achilles tendinitis In tendons, the deposition of positive birefringence rod-like crystals, and the local deposition of non-birefringent neutral lipid droplets are much more common. After trauma, lymphatic obstruction and corresponding parts of patients with pancreatic disease Can be found, only occasionally seen in type IV hyperlipoproteinemia, and sometimes in the lipid droplets found some negative birefringence needle-like lipid crystal deposition, these lipid crystals and hyperlipoproteinemia and arthritis The subtle relationship needs further research.
4. Protein crystals
Langlands et al. reported in detail in 1980 a patient with IgG cryoprecipitated paraprotein disease, which had chronic erosive polyarthritis due to the deposition of a large amount of paraproteins in the joint. The number of white blood cells in the synovial fluid of this patient was 30×. 109/L, 90% of which are neutrophils, have a chronic inflammatory reaction around the deposited protein crystals, and other reports have confirmed this, and found that cryoprecipitated globulin and monoclonal immunoglobulin not only deposit Within the joint, there are also deposits in other parts of the body that can cause embolization of blood vessels when these proteins crystallize in the blood vessels.
5. Foreign body reaction
Many foreign bodies that enter the joint due to trauma, especially puncture wounds, can cause acute and chronic inflammation of the joint. These foreign bodies are often wrapped in synovial tissue and deposited on the wall of the joint cavity after entering the joint, generally using the method of extracting joint fluid. It is difficult to remove it, even the routine examination of joint fluid is negative. If necessary, only arthroscopy or joint surgery can be used to confirm the diagnosis and further treatment. Because many foreign bodies are basically transparent to X-ray in imaging, Magnetic resonance examination of the anterior joint may be helpful for surgery. Under the microscope, the foreign body in the joint and the inflammatory reaction caused by it are various and different. Some plant thorns can cause severe inflammatory reaction and a large amount of local aggregation. The white blood cells and cellulose, which are particularly prominent under polarized light, both the glass fiber particles and the calcium carbonate crystals on the sea urchin puncture have birefringence properties.
Examine
Examination of other crystalline arthropathy
1. The results of counting and classifying leukocytes in synovial fluid of patients with oxalate crystal arthritis are diverse, but the number of white blood cells is usually less than 2 x 109 / L.
2. The number of white blood cells in the synovial fluid of patients with protein crystals is 30×109/L, 90% of which are neutrophils, and the diameter of immunoglobulin crystals is about 60tm. There is no single typical morphology of crystals.
3. The routine examination of foreign body reaction joint fluid is negative.
4. The X-ray findings of patients with oxalate deposition disease are helpful for the diagnosis of the disease. They are typically characterized by flaky calcification of soft tissue or articular cartilage. When it invades bone tissue, it has local ivory or Demineralization changes, but because the light transmission of oxalates is similar to some other crystals, it is sometimes difficult to distinguish them from calcium pyrophosphate deposits or alkaline calcium phosphate deposits by X-ray film alone, but Case reports of no calcification changes were seen on the radiographs of the joints.
5. Because the glucocorticoid crystals are almost completely transparent to the X-ray, the X-ray of the joint can only be used to rule out other diseases when diagnosing the disease.
6. Protein crystals Sometimes, some monoclonal antibodies can be used to further classify immunoglobulin crystals.
7. Foreign body reaction imaging Many foreign bodies are basically transparent to X-ray. Magnetic resonance examination of joints before surgery may be helpful for surgery. Polarization examination is particularly necessary.
Diagnosis
Diagnosis and differentiation of other crystalline arthropathy
1. The diagnosis of patients with oxalate deposition requires the discovery of oxalate crystals in joint fluids or joints, bones and other biopsy tissues. Under normal light microscope, the oxalate crystals in the joint fluid exhibit various forms, but The shape of the double cone and the envelope is the most typical, and the crystal length is 5 to 30 m. If the calcium dyeing method of Alizarin red stain is used, most of the crystals can be colored, sometimes with hydroxyapatite crystals or alkaline phosphoric acid. Calcium crystals are difficult to distinguish, and it is much easier to distinguish oxalate crystals under a polarized light microscope. Except for the typical biconical morphology of the crystal, most oxalate crystals have birefringence properties, only A small portion of the rod-like crystals can exhibit weaker positive, birefringent properties, and are easily confused with calcium pyrophosphate crystals. Under transmission electron microscopy, oxalate crystals exhibit electron densification and foam as well as calcium pyrophosphate crystals. Such changes are not easy to distinguish unless elemental analysis proves that there are only calcium ions in the oxalate crystals, but no pyrophosphate, and other physical methods for identifying crystals, such as X-ray , Electron diffraction, IR spectroscopy, Raman spectroscopy techniques can be very accurate identification of oxalate crystals, in addition, also by pathological diagnosis.
2. The iatrogenic arthritis caused by glucocorticoid deposition is also easy to diagnose. There is a local injection of hormones within a few hours before the onset of the disease. A large number of irregular shapes and irregular shapes can be found in the joint fluid extracted after the onset of the disease. Rod-shaped or cubic crystals exhibit positive or negative birefringence under polarized light microscopy.
3. Lipid crystal arthritis often begins with monoarthritis, the knee joint is the most commonly involved joint, followed by the wrist joint, and there are fewer cases of polyarthritis. The diagnosis of this disease needs to be performed under a polarized light microscope. For the examination of joint fluid, if a large number of liquid crystal microspheres are found inside and outside the cell, further diagnosis can be given in combination with clinical symptoms.
4. The number of white blood cells in the synovial fluid of patients with protein crystals is 30×109/L, of which 90% are neutrophils.
5. The routine examination of joint fluid in patients with foreign body reaction is negative. If necessary, only arthroscopy or joint surgery can be used to confirm the diagnosis and further treatment. Because many foreign bodies are basically transparent to X-ray in imaging, before surgery Magnetic resonance examination of the joints may be helpful for surgery.
