Case presentation A 30-year-old man presents to the ED complaining of anal and lower back pain for the previous two days. He has not achieved any benefit with simple analgesics. The pain is progressively worsening, and he is now finding it uncomfortable to walk or sit down. He is otherwise fit and smokes ten cigarettes a day. Examination Inspection of the anus reveals a 3 cm × 3 cm swelling at the anal margin.
The swelling is warm, exquisitely tender, and fluctuant. There is no other obvious abnormality. What is the most likely diagnosis for this patient and what treatment would you recommend? Which techniques should be used for examining the underlying pathology? *This Case Challenge is from the Editorial team of Docplexus and is meant for educational purposes only.
