Enterobiosis

This is the most common human helminthiasis caused by pinworms, spreading directly and indirectly through contact. The disease is usually symptomatic. The main clinical signs are nocturnal anal itching, insomnia, irritability, and dyspepsia.

In complicated cases of the disease, appendicitis and intestinal perforation are possible.

The diagnosis is made by finding helminth eggs in the folds of the anal area. Sometimes pinworm eggs can be found by examining feces or urine under a microscope. The causative agent is Enterobius vermicularis, a roundworm measuring 9-12 mm in length and 0.3-0.5 mm in diameter, which lives for about 1.5-3 years. It parasitizes in the human small intestine and the upper part of the large intestine. Each mature female lays about 11,000 eggs per day. The life cycle begins when mature eggs are swallowed and reach the upper part of the small intestine. The released larvae travel to the cecum and blind gut, mature and mate there. The adult worm can migrate to other body cavities, usually to the genital tract, abdominal cavity, parenchymal organs. Pinworm females lay eggs around the anal area during nighttime sleep for about 5 weeks. They mature within 6 hours and, if ingested again, can start a new cycle. They remain viable for about 2 weeks. They die at a temperature of 55°C within a few seconds. Up to 500 million cases of the disease are reported worldwide each year. The highest incidence is among children aged 5-10. The source of infection is infected individuals and lack of hygiene, as the infection is transmitted through contact.

Source | Glossary of Most Commonly Used Biomedical Terms and Concepts | Lithuanian University of Health Sciences | Academician Professor Antanas Praškevičius, Professor Laima Ivanovienė