The most frequent sites of involvement are the hands and feet, whereas the spine is less commonly affected. Half of the patients with bony lesions experience pain and stiffness, whereas the other half remain asymptomatic.Periostitis is rarely seen in sarcoidosis and has been found to present itself at the femoral bone. Cause
The exact cause of sarcoidosis is not known. The current working hypothesis is, in genetically susceptible individuals, sarcoidosis is caused through alteration to the immune response after exposure to an environmental, occupational, or infectious agent. Some cases may be caused by treatment with tumor necrosis factor (TNF) inhibitors like etanercept. Genetics
The heritability of sarcoidosis varies according to ethnicity. About 20% of African Americans with sarcoidosis have a family member with the condition, whereas the same figure for European Americans is about 5%. Additionally, in African Americans, who seem to experience more severe and chronic disease, siblings and parents of sarcoidosis cases have about a 2.5-fold increased risk for developing the disease. In Swedish individuals heritability was found to be 39%. In this group, if a first-degree family member was affected, a person has a four-fold greater risk of being affected.Investigations of genetic susceptibility yielded many candidate genes, but only few were confirmed by further investigations and no reliable genetic markers are known. Currently, the most interesting candidate gene is BTNL2; several HLA-DR risk alleles are also being investigated. In persistent sarcoidosis, the HLA haplotype HLA-B7-DR15 is either cooperating in disease or another gene between these two loci is associated.
Salsalate is a medication that belongs to the salicylate and nonsteroidal anti-inflammatory drug (NSAID) classes. Salsalate is the generic name of a prescription drug marketed under the brandnames Mono-Gesic, Salflex, Disalcid, and Salsitab. Other generic and brand name formulations may be available. Mechanism of action
Relative to other NSAIDs, salsalate has a weak inhibitory effect on the cyclooxygenase enzyme and decreases the production of several proinflammatory chemical signals such as interleukin-6, TNF-alpha, and C-reactive protein.The mechanism through which salsalate is thought to reduce the production of these inflammatory chemical signals is through the inhibition of IκB kinase resulting in decreased action of NF-κB genes. This mechanism is thought to be responsible for salsalates insulin-sensitizing and blood sugar lowering properties. Medical uses
Salsalate may be used for inflammatory disorders such as rheumatoid arthritis or noninflammatory disorders such as osteoarthritis. Safety
The risk of bleeding is a common concern with use of the NSAID class of medications. However, the bleeding risk associated with salsalate is lower than that associated with aspirin use. Research
Salsalate has been proposed for the prevention and treatment of type 2 diabetes mellitus due to its ability to lower insulin resistance associated with inflammation and may be useful in prediabetes. However, the use of salsalate to prevent the progression from prediabetes to type 2 diabetes mellitus has received limited study. History
Salsalate had been suggested as possible treatment for diabetes as early as 1876. Synthesis


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