Laboratory Tests

Laboratory tests are of little benefit in patients with benign anorectal disease.

A full blood count should be carried out in patients with any rectal bleeding to look for anaemia. Inflammatory markers, such as white cell count (WCC), c-reactive protein (CRP) or erythrocyte sedimentation rate (ESR) are of little benefit in patients with an obvious anorectal abscess, as this will not change ED management.

These investigations may be of benefit when a patient presents with anorectal pain and a deep abscess is suspected.

Routine investigations are of most value if an underlying systemic disease is suspected. All patients with an anorectal abscess, particularly if recurrent, should have a blood sugar (BM) checked to exclude diabetes.