Anal thrombosis

Fabian Dupont is a freelance writer in the medical department. The human medicine specialist is already doing scientific work in Belgium, Spain, Rwanda, the USA, Great Britain, South Africa, New Zealand and Switzerland, among others. The focus of his doctoral thesis was tropical neurology, but his special interest is international public health and the comprehensible communication of medical facts.

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Anal thrombosis (anal vein thrombosis) is a painful swelling in the anus area caused by a venous blood clot. The differentiation from hemorrhoids is often not easy. Unlike hemorrhoids, anal thromboses are very painful and do not "fall" (prolapse) out of the anal canal. Here you can read everything you need to know about the causes, symptoms and treatment of anal thrombosis.

ICD codes for this disease: ICD codes are internationally recognized codes for medical diagnoses. They can be found, for example, in doctor's letters or on certificates of incapacity for work. K64

What is anal thrombosis?

The anal thrombosis (anal vein thrombosis) was formerly also called "external hemorrhoids". However, anal thromboses and hemorrhoids are two different clinical pictures with different symptoms and development mechanisms:

Hemorrhoids and anus thrombosis are both caused by blood clots in a blood vessel. In the case of hemorrhoids, however, fine arterial plexuses in the anal canal are affected, which play a role in the closing mechanism of the anus. Anal thrombosis, on the other hand, affects the plexus of veins around the anus. This means that in anal thrombosis the palpable nodes are not in the anal canal (as in hemorrhoids), but directly at the exit and are therefore visible at all times. Hemorrhoids are only visible from the outside in advanced stages - they emerge from the anal canal (severity level 2, 3) when there is increased abdominal pressure (e.g. when pressing during bowel movements) or are permanently curved outward (level 4).

Unlike hemorrhoids, anal thrombosis is also very painful, making it almost impossible to sit. In the case of hemorrhoids, on the other hand, an uncomfortable itching and pressure is predominant.

How does the anal thrombosis develop?

The lumps on the edge of the anus are blood clots in the small veins that are found around the anus. A particularly high abdominal pressure contributes to their development. This is caused by chronic constipation, obesity or long years of excessive pressing exercises, such as those done in strength training.

Abdominal pressure is also increased during pregnancy, and the unborn child rests on the plexus of veins in the anus. During the birth process there is also strong pressing. Anal thrombosis (like hemorrhoids) is therefore a common problem during pregnancy and after delivery.

In addition, as for any type of thrombosis, general risk factors such as little exercise (e.g. long and frequent sitting), vascular diseases and blood clotting disorders also apply to anal thrombosis. Taking the contraceptive pill is also associated with a general risk of thrombosis. Other hormonal influences, such as the monthly fluctuations in hormones in women, can also promote anal thrombosis.

How is anal thrombosis treated?

Anus thrombosis can be treated in different ways, depending on its size and the pain it causes. The doctor can pierce a fresh thrombosis under anesthesia to remove the blood clot. The wound then usually heals without any consequences. In the case of minor thrombosis in the anus, treatment with ointments and painkillers is often sufficient.

How can an anal thrombosis be avoided?

Since long sitting and high abdominal pressure (pressing exercises during weight training, pressing during bowel movements) are risk factors for the development of an anal thrombosis, both should be limited as much as possible.

Frequent constipation also promotes anal vein thrombosis: this can often be counteracted by more physical activity and a change in diet. If that doesn't help, you can soften the stool with the help of swelling agents. Seek advice from your doctor on how to manage your constipation.

Mechanical stress on the anus (as in anal intercourse) is another risk factor that plays a role in the development of an anal thrombosis and should therefore be avoided.

Tags:  Diagnosis pregnancy eyes