as pyoderma gangrenosum or Sweet's syndrome; vasculitic processes such as cryoglobulinemia; calciphylaxis (often seen in people with end-stage kidney disease but may also occur with medications such as warfarin); cancers such as squamous cell carcinoma (Marjolin's ulcer) or myelodysplastic syndrome; neuropathy (e.g., diabetic peripheral neuropathy); or atypical infections such as nocardiosis, sporotrichosis, or mycobacterial infections. Prevention Compression stockings appear to prevent the formation of new ulcers in people with a history of venous ulcers. Treatment The main aim of the treatment is to create such an environment that allows skin to grow across an ulcer. In the majority of cases this requires finding and treating underlying venous reflux. The National Institute for Health and Care Excellence (NICE) recommends referral to a vascular service for anyone with a leg ulcer that has not healed within two weeks or anyone with a healed leg ulcer. Most venous ulcers respond to patient education, elevation of foot, elastic compression, and evaluation (known as the Bisgaard regimen). Exercise together with compression stocking increases healing. There is no evidence that antibiotics, whether administered intravenously or by mouth, are useful. Silver products are also not typically useful, while there is some evidence of benefit from cadexomer iodine creams. There is a lack of quality evidence regarding the use of medical grade honey for venous leg ulcers. The recommendations of dressings to treat venous ulcers vary between the countries. Antibiotics are often recommended to be used only if so advised by the physician due to emergence of resistance of bacteria to antibiotics. This is an issue on venous ulcers as they tend to heal slower than acute wounds for example. Natural alternatives that are suitable for the longer term use exists on the market such as honey and resin salve. These products are considered as Medical Devices in EU and the products have to be CE marked. There is uncertain evidence whether alginate dressing is effective in the healing of venous ulcer when compared to hydrocolloid dressing or plain non-adherent dressing. It is uncertain whether therapeutic ultrasound improve the healing of venous ulcer. Compression therapy Non-elastic, ambulatory, below knee (BK) compression counters the impact of reflux on venous pump failure. Compression therapy is used for venous leg ulcers and can decrease blood vessel diameter and pressure, which increases their effectiveness, preventing blood from flowing backwards. Compression is also used to decrease release of inflammatory cytokines, lower the amount