From the Guidelines
A rectal abscess is diagnosed through a combination of clinical evaluation and diagnostic tests, with a focused medical history and complete physical examination, including a digital rectal examination, being the primary methods of diagnosis 1. The diagnosis of a rectal abscess typically involves a healthcare provider taking a medical history and performing a physical examination, which includes a digital rectal examination to feel for painful swelling or masses.
- Patients typically present with severe rectal pain, swelling, redness, and sometimes fever or difficulty sitting.
- Laboratory tests may include a complete blood count to check for elevated white blood cells indicating infection.
- Imaging studies such as CT scans, MRI, or endoanal ultrasound might be ordered to determine the exact location and extent of the abscess, particularly for deeper abscesses that aren't visible externally, in cases of atypical presentation, or suspicion of occult supralevator abscesses, complex anal fistula, or perianal Crohn’s disease 1. In some cases, the doctor may need to perform an examination under anesthesia for a more thorough assessment.
- The use of imaging techniques, such as MRI, CT scan, or endosonography, can be helpful in diagnosing anorectal abscesses, especially in cases where the physical examination is unclear or the patient has a complex medical history 1. Once diagnosed, treatment usually involves surgical drainage of the abscess under local or general anesthesia, followed by antibiotics if there are signs of spreading infection.
- Prompt diagnosis and treatment are essential to prevent complications like fistula formation or sepsis. The clinical presentation of anorectal abscesses can vary widely, and a thorough medical history and physical examination are crucial in making an accurate diagnosis 1.
- The diagnosis of anorectal abscesses requires a high degree of suspicion, especially in older and debilitated patients, or those with diabetes or other forms of immunosuppression, as symptoms may be absent or diminished in these cases 1.
From the Research
Diagnosis of Rectal Abscess
To diagnose a rectal abscess, several methods can be employed, including:
- Digital rectal examination to check for fluctuance or masses 2
- Imaging studies such as computed tomography (CT) scan to visualize the abscess 2
- Transrectal ultrasound, which has been shown to be a reliable method for diagnosing prostatic abscesses and may be applicable to rectal abscesses as well 3
Signs and Symptoms
Rectal abscesses can present with various signs and symptoms, including:
- Pain and swelling in the anal or rectal area
- Fluctuance or masses on digital rectal examination
- Penile discharge, although this is a rare presentation 2
- Scrotal pain and swelling
Importance of Accurate Diagnosis
Accurate diagnosis of a rectal abscess is crucial to guide treatment and prevent complications. A thorough evaluation, including digital rectal examination and imaging studies, can help identify the presence of an abscess and any associated fistulae 4, 5, 6