Pinworm (Enterobiasis) Clinical Presentation

Updated: Feb 10, 2023
  • Author: Sun Huh, MD, PhD; Chief Editor: Michael Stuart Bronze, MD  more...
  • Print

History and Physical Examination

The patient history of pinworm infection, also called enterobiasis, includes itching or prickling pain in the anal area (usually at nighttime or in the early morning), intense anal itching, restless sleep or difficulty sleeping, and, rarely, abdominal discomfort or loss of appetite. [8] Other symptoms include irritability and, in females, vaginal itching. Most patients, however, are asymptomatic. [1, 2]

Although a hospital-based study of children aged 2-12 years found that perianal itching was not significantly more common in children who are infected than in children who are uninfected, persons who are Enterobius egg–positive typically visit a physician because of perianal itching. [1, 2]

The pale-colored female pinworm (10 mm) may be seen in the perianal region with the naked eye. The worm's appearance is easily confused with bits of cotton thread. Eggs (30 μm X 50-60 μm) usually are not seen without a microscope. Perianal excoriations secondary to scratching may be found. [1, 2]