Miliary nodules arising from subcutaneous deposits

Introduction 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 frequently. Patients treated with hemodialysis or peritoneal dialysis for renal failure can also develop oxalate deposits in the intervertebral disc, which often lead to disruption and degeneration of the intervertebral disc. Deposition of oxalate crystals in other tissues can also lead to the following consequences: local necrosis, myocardial lesions or heart block due to insufficient blood supply, miliary nodules, peripheral neuropathy and aplastic disorders in subcutaneous deposition Anemia.

Cause

Deposition of oxalate crystals in other tissues results in the appearance.

an examination

Related inspection

Urine oxalate joint examination bone and joint soft tissue CT examination white blood cell count (WBC) blood test

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 × 109 / L.

The X-ray findings of patients with oxalate deposition 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, there is local ivory or demineralization. Change. However, since the light transmission of oxalates is similar to some other crystals, it is sometimes difficult to distinguish them from calcium pyrophosphate deposition or alkaline calcium phosphate deposition by X-ray film alone. However, there were no reports of any calcification changes on the joint X-ray films.

Differential diagnosis

1. Iatrogenic arthritis caused by glucocorticoid deposition: iatrogenic arthritis caused by glucocorticoid deposition, even patients with osteoarthritis that are sensitive to topical treatment of hormones, are now found in short-term after hormone injection An increase in the number of inflammatory cells and an increase in phagocytosis also occurs in the internal joint fluid. The inflammation caused by this hormone deposition is easily distinguished from the infection inflammation caused by local operations, the former often occurs within 8 hours after the injection, while the latter takes 1 day or longer to show obvious symptoms. Joint inflammation caused by glucocorticoid deposition lasts for a short period of time, and its symptoms gradually relieve with the dissolution of hormone particles, and the hormone released by dissolution itself can inhibit the further development of inflammation.

2. Lipid crystal arthritis: Clinically, it usually begins with monoarthritis. The knee joint is the most commonly affected joint, followed by the wrist joint, and cases of polyarthritis are occasionally reported. The diagnosis of this disease requires examination of the joint fluid under a polarized light microscope. The white blood cell count of the joint fluid is (10-40)×109/L, mainly neutrophils. Typical lipid liquid crystal microspheres have a diameter of about 2-20 m. Due to the phenomenon of birefringence, an equal arm cross shadow can be found in the microsphere. If only a small amount of microspheres exist in the field of view, it usually has little clinical significance. However, 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.

3. Protein crystals: Langlands et al. reported in detail in 1980 a patient with IgG cryoprecipitated paraprotein disease, secondary to chronic erosive polyarthritis due to the deposition of a large amount of paraproteins in the joints, in this patient's synovial fluid. The number of white blood cells is 30 × 109 / L, 90% of which are neutrophils, and there is a chronic inflammatory reaction around the deposited protein crystals. Later, other reports confirmed this and found that cryoprecipitated globulin and monoclonal immunoglobulin are not only deposited in the joint, but also deposited in other parts of the body. When these proteins crystallize in blood vessels, they can cause embolization of blood vessels.

4. Foreign body reaction: Many foreign bodies entering 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. It is difficult to remove the joint fluid by removing the joint fluid. Even the routine examination of the joint fluid is negative. If necessary, only arthroscopy or joint surgery can be used to confirm the diagnosis and further treatment. Since many foreign bodies are basically transparent to X-rays in imaging, magnetic resonance examination of the joints before surgery 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. The thorns of some plants can cause severe inflammatory reactions, local accumulation of large amounts of 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.

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