True regarding colovesical fistula

.* Left sided growth presents with colicky pain, altered bowel habits (alternating constipation and diarrhoea), palpable lump, distension of abdomen due subacute/ chronic obstruction. Later may present like complete colonic obstruction. Tenesmus, with passage of blood and mucus, with alternate constipation and diarrhoea, is common. Bladder symptoms may warn colovesical fistula. ref:SRB&;s manual of surgery ,ed 3,pg no 838