A patient who reports to the hospital because of an anal abscess is often treated as not seriously ill. They are often operated by the least experienced doctor on duty, and the procedure happens to be limited to a shallow incision under local anesthesia at the hospital emergency ward. And yet, in about 40% of cases, abscess may initiate the development of chronic proctological disease and anal fistula. Furthermore, the unloaded or insufficiently empty abscess may cause septic complications that directly threaten the patient’s life. There are no accurate data on the occurrence of rectal abscesses. Not all patients report to the doctor, as some abscesses undergo spontaneous perforation. Some patients are operated on an outpatient basis, so epidemiological data are generally only for patients hospitalized for abscesses. In the United States, about 100,000 patients with anorectal infection are reported each year, and the average age of the patient is 40 years. The disease affects twice as much men as women (1, 2).

For many years, researchers have agreed that the cause of the majority of inflammatory diseases in the anus, including abscesses and anal fistula, is the growing infection in the anal crypts. This theory dates back to the nineteenth century, when in 1880, Hermann and Desfosses first described the anal glands as an anatomic structure in the anal canal. The theory was also confirmed by other great coloproctologists such as Lockhart-Mummery (1929), Gordon-Watson and Dodd (1935), Kratzer and Dockerty (1947). It was also confirmed in later works by Eisenhammer (1956, 1977, 1961) and Parks (1961), as well as by contemporary coloproctologists such as Abcarian (1, 3). The anal glands are anatomical structures of the anal canal of every human being. If clogged, they can cause infection. Infection spreads along the intercostal space, between the muscles of the internal and external sphincter in various directions: most often down with the power of gravity, to the edge of the anus forming peripheral abscesses (subcutaneous). It can also pass through the muscle of the external sphincter into the sinuses and the aneurysms, forming sciatic and rectal abscesses. It may spread along the rectum wall to form high and low intersphincteral abscesses, or above the levator muscles to create surgeon abscesses. High over-leverage abscesses may also be caused by infectious diseases in the pelvis, such as appendicitis, diverticulitis, and genital infections. This division of abscesses presented by Corman and based on the location of abscesses in anatomical spaces is so logical and practical that it works in the literature to this day, it is historical, though.

Apart from inflammation of the anal glands, there are other reasons for the formation of anal abscesses. In old textbooks, tuberculosis, actinomycosis and venereal diseases are among the first reported non-cryptal causes of anal abscesses. At present, patients with inflammatory bowel diseases such as ulcerative colitis and Crohn’s disease often suffer from abscesses. Other common, frequent causes of anal abscess development include immunodeficiency syndrome in the course of HIV infection, as well as reduced immunity in the course of immunosuppression or chemotherapy obtained (patients with leukemia, patients prepared for bone marrow transplantation) (tab. 1). In her practice, the author had to deal with patients in whom anal abscess was the first clinical symptom of HIV infection twice. In patients at risk, the possibility of coexisting syphilis and abscess development on the basis of the rectal syphilis lumps should also be taken into account. An anal abscess may also arise as a result of infected traumatic anal wounds, introduction of foreign bodies into the anal canal or due to radiotherapy in the area.

Bacterial cultures from abscesses most often exhibit mixed bacterial flora, mainly Escherichia coli, followed by Proteus vulgaris, Staphylococcus aureus. In one study based on a large group of 183 patients treated for anal abscesses, researchers compared bacterial flora in patients with and without diabetes. In 60% of patients with diabetes, Klebsiella pneumoniae was found to be the most frequent pathogens, whereas in non-diabetic patients, the most common pathogen was Escherichia coli (67.1%), sensitive to first generation cephalosporins, which was also observed by us (4).

Most patients with low anal abscesses do not require diagnostic tests. An interview and a physical examination are enough to diagnose an abscess. The primary clinical symptom is anal pain and febrile states. In the proctology examination, painful swelling of the tissues is found in the anal area, and the skin is red and hot (fig. 1).