Diagnosis and Management of Intersphincteric Abscess

Clinical Presentation and Diagnosis

The American College of Radiology suggests that throbbing anal pain is the hallmark symptom of anorectal abscesses, distinguishing them from other anorectal conditions, in patients with fever and pain on digital rectal examination 1, 2, 3
The World Journal of Emergency Surgery indicates that fever without significant systemic signs suggests a contained infectious process rather than extensive perianal sepsis, in patients with anorectal abscesses 2, 3
Pain on digital rectal examination is characteristic of deeper abscesses, particularly intersphincteric and supralevator types, where DRE reveals a tender, indurated area above the anorectal ring, according to the World Journal of Emergency Surgery 2, 3
Normal colonoscopy effectively rules out mucosal pathology, inflammatory bowel disease, and malignancy that could present similarly, as stated by the Journal of the American College of Radiology and the World Journal of Emergency Surgery 1, 2
Intersphincteric abscesses are often occult on external examination but cause significant pain on rectal examination, making them challenging to diagnose clinically, according to the World Journal of Emergency Surgery 2, 3

The World Journal of Emergency Surgery recommends that hemorrhoids be considered in the differential diagnosis, but the presence of fever strongly argues against uncomplicated hemorrhoidal disease 4
Anal fissures cause sharp, tearing pain during and after defecation, not throbbing pain, and are best visualized by effacing the anal canal with opposing traction on the buttocks, not through DRE, as stated by the World Journal of Emergency Surgery and other sources 5
Submucosal abscesses are high abscesses that may have few local symptoms but significant systemic symptoms, and would typically present with more pronounced systemic signs than described, according to the World Journal of Emergency Surgery 6, 2

Anorectal abscesses are classified by anatomical location: intersphincteric, perianal, ischiorectal (ischioanal), and supralevator, as stated by the World Journal of Emergency Surgery and the Journal of the American College of Radiology 2, 3, 1
Deeper abscesses (intersphincteric, supralevator) can be challenging to diagnose because they may be occult on physical examination, with DRE revealing only a tender, indurated area, according to the World Journal of Emergency Surgery 2, 3
Symptoms are frequently absent or diminished in older, debilitated, diabetic, or immunosuppressed patients, requiring a high degree of suspicion, as recommended by the World Journal of Emergency Surgery 2, 3

The World Journal of Emergency Surgery suggests checking serum glucose, hemoglobin A1c, and urine ketones to identify undetected diabetes mellitus 3
Requesting complete blood count, serum creatinine, and inflammatory markers (C-reactive protein, procalcitonin, lactates) is recommended to assess severity, according to the World Journal of Emergency Surgery 3
Considering imaging (MRI, CT scan, or endoanal ultrasound) for suspected intersphincteric or supralevator abscesses is indicated, as these are difficult to diagnose clinically, as stated by the World Journal of Emergency Surgery 2, 3
Prompt surgical drainage is indicated once the diagnosis is confirmed, as undrained anorectal abscesses can expand into adjacent spaces and progress to systemic infection, according to the World Journal of Emergency Surgery and other sources 6, 2