Set Color of Autocomplete TextBox items in Wondows Forms Application

            cn.Open();
            SqlCommand cmd = new SqlCommand("select patientname from opddata", cn);
            SqlDataReader dr = cmd.ExecuteReader();
            AutoCompleteStringCollection mycollection = new AutoCompleteStringCollection();
            while (dr.Read())
            {
                mycollection.Add(dr.GetString(0));
            }

            txtpatientname.AutoCompleteCustomSource = mycollection;
            cn.Close();

Hello sir i have fetched some name in the textbox with help of above code. And now i want to set color to the items of textbox how to do that

its an windows based app

autocompletestringcoll is an method to store multiple data to display in textbox or dropdownlist

i want to set color to the items which i had got in the object of autocompletestringcollection