Differential Diagnosis for a Small Purple Ball in the Anus
- Single most likely diagnosis
- Hemorrhoid: This is the most likely diagnosis given the description of a small purple ball in the anus, which is consistent with an external hemorrhoid. The associated pain is also typical for a thrombosed external hemorrhoid.
- Other Likely diagnoses
- Anal tag or skin tag: This could be a small, benign growth that might appear purple due to its vascular nature. However, it typically wouldn't cause significant pain unless it becomes irritated or thrombosed.
- Anal fissure with associated hematoma: While an anal fissure itself might not appear as a "ball," an associated hematoma could present in this manner, especially if it's small and localized.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Rectal cancer: Although rare and less likely given the acute presentation, any new anal or rectal mass should prompt consideration of malignancy, especially in older adults or those with risk factors.
- Anal melanoma: This is a rare but aggressive form of cancer that could present as a pigmented lesion in the anal area. Early detection is crucial for treatment outcomes.
- Thrombosed or infected anal gland cyst: These can present as painful, swollen masses near the anus and require prompt medical attention to prevent serious complications like abscess formation.
- Rare diagnoses
- Angioma or vascular malformation: These are rare vascular lesions that could appear as purple masses due to their nature. They are typically congenital but can become apparent at any age.
- Dermatological conditions (e.g., angiokeratoma, pyogenic granuloma): Certain skin conditions can cause lesions that might resemble a small purple ball, though they are less common in the anal area.