Intersphincteric anal abscess, a rare cause of axial low back pain: a case report

A 60-year-old male patient presented with axial lower back pain. He had suffered from this for one month. Within a week, the patient\'s pain had increased, and he experienced additional symptoms of fever, malaise, and weight loss. Lumbar MRI revealed an intersphincteric anal abscess extending to the level of the lower lumbar vertebrae. The patient was then referred to a general surgeon. After the abscess was drained and the patient was treated with broad-spectrum antibiotics, the pain resolved within one week. This case illustrates a rare cause of lower back pain, where an anal abscess was not initially considered despite a normal physical examination, and an advanced intersphincteric abscess was revealed by lumbar MRI, raising concerns about malignant metastasis.