- Immunosuppression (HIV positive, diabetes mellitus or drugs affecting immune response) Active tuberculosis (TB) or a history of TB Previous forearm free flap Disorders of circulation (e.g. peripheral vascular disease, vasculitis) History of prior malignancy Renal failure and not on a renal replacement programme Systemic disease deemed by the investigator serious enough to preclude the use of immunosuppression agents Mental illness Patients who are unwilling, unable or unlikely to comply with immunosuppressive treatment and regular follow-up.