Differential Diagnosis for Internal Rectal Pain
Single Most Likely Diagnosis
- Anal Fissure: A tear in the lining of the anus, which can cause severe pain during and after bowel movements, especially if the fissure is deep or large. This condition is common and often presents with sharp, stabbing pain.
Other Likely Diagnoses
- Hemorrhoids: Swollen veins in the lowest part of the rectum or anus, which can cause pain, especially if they are thrombosed. Internal hemorrhoids can cause pain if they prolapse or become strangulated.
- Proctalgia Fugax: A condition characterized by sudden, severe pain in the rectum that lasts for a few seconds to a few minutes. It is often caused by muscle spasms in the rectal area.
- Levator Ani Syndrome: A condition where there is chronic pain in the rectal area due to spasms of the levator ani muscle. The pain is often aching or pressure-like and can be exacerbated by sitting.
Do Not Miss Diagnoses
- Rectal Cancer: Although less common, rectal cancer can cause internal rectal pain, especially if the tumor is large or has invaded surrounding structures. Early detection is crucial for effective treatment.
- Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can cause rectal pain, along with other symptoms such as diarrhea, bleeding, and weight loss. Missing these diagnoses can lead to significant morbidity.
- Ischiorectal Abscess: An abscess in the ischiorectal fossa can cause severe, constant pain in the rectal area, along with fever and swelling. Prompt drainage is necessary to prevent complications.
Rare Diagnoses
- Coccydynia: Pain in the coccyx (tailbone) area, which can sometimes be referred to the rectum. It is often caused by a fall onto the buttocks or prolonged sitting.
- Pudendal Neuralgia: A condition characterized by pain in the distribution of the pudendal nerve, which can include the rectal area. The pain is often burning or stabbing and can be exacerbated by sitting.
- Solitary Rectal Ulcer Syndrome: A condition where there is a single ulcer in the rectum, often caused by chronic straining during bowel movements. It can cause rectal pain, along with bleeding and difficulty with bowel movements.