Rare causes of skin ulcers include pyoderma gangraenosum, lesions caused by Crohns disease or ulcerative colitis, granulomatosis with polyangiitis, morbus Behçet and infections that are usually seen in those who are immunocompromised, for example ecthyma gangraenosum. It is important to consider such causes if the skin ulcerations dont show improvement with antibiotic treatments and when other systemic symptoms are present. It is advised not to use surgical procedures on ulcerations caused by Behçet or pyoderma gangraenosum since those diseases usually exhibit pathergy. Diagnosis
Grading
Wagners grading of ulcer follows:

Management
Investigations
Some of the investigations done for ulcer are:: 19 
Study of discharging fluid: Culture and sensitivity
Edge biopsy: Edge contains multiplying cells
Radiograph of affected area to look for periostitis or osteomyelitis
Fine needle aspiration cytology (FNAC) of lymph node
Chest X-ray and Mantoux test in suspected tuberculous ulcer

Treatment
Skin ulcers may take a very long time to heal. Treatment is typically to avoid the ulcer getting infected, remove any excess discharge, maintain a moist wound environment, control the edema, and ease pain caused by nerve and tissue damage. Topical antibiotics are normally used to prevent the ulcer getting infected, and the wound or ulcer is usually kept clear of dead tissue through surgical debridement. Commonly, as a part of the treatment, patients are advised to change their lifestyle if possible and to change their diet. Improving the circulation is important in treating skin ulcers, and patients are consequently usually recommended to exercise, stop smoking, and lose weight. In recent years, advances have been made in accelerating healing of chronic wounds and ulcers.
In the second stage the redness of the skin becomes more pronounced, swelling appears, and there may be some blisters and loss of outer skin layers. During the next stage, the skin may become necrotic down through the deep layers of skin, and the fat beneath the skin may become exposed and visible. In stage 4, deeper necrosis usually occurs, the fat underneath the skin is completely exposed, and the muscle may also become exposed. In the last two stages the sore may cause a deeper loss of fat and necrosis of the muscle; in severe cases it can extend down to bone level, destruction of the bone may begin, and there may be sepsis of joints. Chronic ulcers may be painful. Most patients complain of constant pain at night and during the day. Chronic ulcer symptoms usually include increasing pain, friable granulation tissue, foul odour, and wound breakdown instead of healing. Symptoms tend to worsen once the wound has become infected. Venous skin ulcers that may appear on the lower leg, above the calf or on the lower ankle usually cause achy and swollen legs. If these ulcers become infected they may develop an unpleasant odour, increased tenderness and redness. Before the ulcer establishes definitively, there may be a dark red or purple skin over the affected area as well as a thickening, drying, and itchy skin.