What is the common cause of anorectal abscesses?

Anorectal abscesses are most commonly caused by bacterial infections, specifically from bacteria that are normally present in the gastrointestinal tract. The most prevalent organisms involved are often anaerobic bacteria, such as Bacteroides and Escherichia coli, which can proliferate due to obstruction of the anal glands. This obstruction can lead to an accumulation of pus, resulting in an abscess.

While viral, fungal, and parasitic infections can cause other types of conditions in the anorectal area, they are not typically responsible for abscess formation. The bacterial infections, particularly those derived from skin or gut flora, are directly linked to the etiological development of anorectal abscesses and are the primary concern in clinical management. Understanding the microbiological causes of these infections is crucial for proper diagnosis and treatment.