hi sir/madam, Thanks for your question on Healthcare Magic. The possible cause for your discoloration is VENOUS STASIS DERMATITIS. Brown discoloration that forms on the lower part of the leg, usually around the ankle, can be attributed to a skin condition known as venous stasis dermatitis. This inflammatory skin disorder is actually caused by problems with the veins underneath the skin’s surface. When the veins don’t work properly, blood and fluids can leak out of the veins and cause skin discoloration. Venous stasis dermatitis often begins with minor irritation and itchiness of the skin in the affected area. Over time, the skin will start to thin and look more translucent. If the problem is not addressed at this point, the skin can become discolored and take on a thick, leathery texture. Unfortunately, these final symptoms are often permanent, even if the underlying vein disorder is properly treated. When venous stasis dermatitis is diagnosed, the treatment is focused on addressing the diseased vessels and restoring healthy blood flow. This can be done through a variety of minimally-invasive procedures that collapse the affected vein so that it can be reabsorbed by the body. With the vein eliminated, blood naturally reroutes to healthier vessels nearby. If you have discoloration around the lower part of the leg, make an appointment with a vein specialist to get an accurate diagnosis and treatment option. This is particularly true if your discoloration is accompanied by symptoms like leg pain and heaviness or swelling of the lower extremity. The sooner you treat the vein condition, the fewer complications you will experience. Hope i was helpful. Have a healthy day.