oxyuriasis

Oxyuriasis: description

The oxyuriasis is caused by an infection with the pinworm. Some physicians call the infection with the intestinal parasites also enterobiose (in English: enterobiasis). The name is based on the Latin name of the worm: Enterobius vermicularis.

Parasitic diseases are usually a rarity in Germany and are often a traveler’s item from the tropics. One exception is oxyuriasis, which is also common in developed countries like Germany. Worldwide, approximately 400 million people are infected with pinworms.

Oxyuriasis: symptoms

The pinworm (Enterobius vermicularis) often go unnoticed for a long time, as there are no symptoms. The most common and specific symptom of oxyuriasis is the itching of the anus and vagina. Since the female worms usually emerge from the anus at night to distribute their eggs in the skin folds of the surrounding skin, the itching is particularly annoying at night. Inspecting the chair or underpants sometimes discovers small worms. The patient usually seeks the doctor for these two reasons.

In infants, a behavioral or developmental disorder may be noticed. Due to the itching, there are sometimes also indirect sleep disturbances. In girls and women there is a risk that the worm attacks the female genitals and causes an inflammatory reaction there. In very strong infestation, inflammatory processes in the intestinal wall rarely occur. Such events may end in appendicitis or a perforated (burst) bowel. If you do not react quickly in such situations, there is an acute danger to the patient’s life. As a rule, enterobiose / oxyuriasis is a harmless disease and complications are very rare.

Oxyuriasis: causes and risk factors

Pinworms are more common in babies and children, but sometimes in adults. Women are generally more affected than men. The pinworm is a small, filamentous parasite, which belongs to the nematode (Fadewürmer).

As parasites, they belong to the living organisms that live in another organism (for example, in humans) and feed themselves at the expense of them. The pinworm attacks only humans. The adult worms live in the colon, where they develop from larvae to adult worms.

The male is about half a millimeter, the female up to 1.5 inches tall. After fertilization, the female migrates to the anus and preferably places up to 10,000 eggs at night in the skin folds directly around the anus. This causes an itch, through which the eggs quickly reach the hands and under the fingernails of the infected. If the contaminated fingers are taken into the mouth, self-infection is possible.

In addition, the eggs are transferred to objects during food preparation or by hand contact. Since the eggs remain infectious for up to three weeks in a humid environment, re-infection by remaining eggs is possible even after successful treatment. The worms begin at body temperature after just a few hours their larval development in the freshly laid eggs. After five to six weeks, the worms are sexually mature and start egg production.

The oxyuriasis is transmitted especially via hand contact. An important risk factor is therefore lack of hygiene and careless hand washing. Since the infection occurs especially in infants, the risk of oxyuriasis is higher in nursery schools or nurseries than at home. The parasite can also be transmitted during sexual intercourse. Especially anal-oral practices make infection possible.

Oxyuriasis: examinations and diagnosis

For the doctor, the anal itching is often the first sign that indicates a possible oxyuriasis infection. First stop is usually the family doctor. This will first ask the patient extensively. He could ask questions like:

• When does the itching mainly occur?
• Have you observed white worms in the feces or the anus?

Further evidence of a pinworm infestation may be a blood test. There are more and more immune cells that fight targeted against parasites, so-called eosinophils. If their number is increased, it is called an eosinophilia.

However, the best method is the microscopic proof of the eggs early in the morning, before cleaning or defecation. This is usually done with a transparent adhesive film that is glued to the skin around the anus. The tape is carefully peeled off and placed on a microscope slide. The eggs can be detected directly using a microscope.

In some cases, especially in case of heavy infestation, the small white worms are already recognizable on the chair. When the worms reach the outside world, they die quickly. Sometimes, however, you can still see them alive in the chair that has left the chair. Especially the females stay close to the intestinal exit. They are recognizable by their white, thread-like shape and their whip-like movements.

Oxyuriasis: treatment

If infestation with pinworms has been detected, or if there is a suspicion of infection, a few points should be taken to get rid of the parasitic infestation as quickly as possible. In order to avoid immediate reinfection, it is necessary to take some hygiene measures. At the same time, drugs are administered to kill the worms in the gut.

Hygienic measures in oxyuriasis (enterobiasis)

To avoid further spread and reinfection, the following instructions should be observed. In particular the Handygiene is to be considered.

• Thorough hand washing after using the toilet and before contact with food
• Only chlorhexidine-containing disinfectants kill the eggs effectively. Thorough hand washing, however, is usually sufficient.
• Wash underwear, pajamas and sheets with kitchen linen.
• Change underwear every night.
• Tight underpants during the night prevent unconscious scratching.
• For anal itching before bedtime apply cream: (eg: Skinsept mucosa)
• Clean toys and possible contaminated items with hot water
• Keep fingernails short.
• Biguanide and phenolic detergents are suitable for surface cleaning.
• Household vacuum cleaners distribute the eggs only.

Medicines for oxyuriasis (enterobiasis)

The treatment of oxyuriasis is very simple. A single tablet is usually sufficient to kill the pinworms in the intestine. Since reinfections are common, therapy should be repeated after 14 days. All infected persons should start the drug therapy at the same time to avoid repeated, mutual infection. Often, people living nearby, such as family members, are treated as a precautionary measure. There are several medications that successfully kill pinworms. This group of substances is called anthelmintics. The two commonly used medications are:

• mebendazole
• pyrantel

Oxyuriasis: disease course and prognosis

Oxyuriasis is usually harmless. Only rarely does it come to complications. It is common for children to re-infect themselves the same night. By finger / thumb sucking the eggs get directly from the anus to the mouth.

The therapy is very well tolerated and it comes only in very few cases to side effects. Even complications are rare. So the worm eggs can get into the vagina, and develop there. This triggers an inflammatory reaction, which can be associated with pain and possibly discharge. In case of heavy infestation, bowel function may be limited and inflammation or perforation may occur. These potentially life-threatening courses are very rare, and are associated with a Stuhlverhalt, or abdominal / abdominal pain. The oxyuriasis is a very common, treatable child disease, but it does not pose a major risk to the child’s health.