Pinworm Infection (Enterobiasis) – Symptoms, Diagnosis & Treatment

Pinworm Infection (Enterobiasis) – Symptoms, Diagnosis & Treatment

Enterobius vermicularis, also known as pinworm, threadworm, and seatworm, is a highly infectious parasitic helminth that primarily affects the pediatric population.^1,2 Approximately 30% of children worldwide, and up to 60% of children in developing countries, will experience enterobiasis, a pinworm infection. The highest prevalence of enterobiasis is in male children aged 5 – 14 years. Globally, more than a billion individuals have enterobiasis.³

Pinworm Infection – Transmission

Humans are the only known hosts for pinworms; therefore, pets cannot be the primary source of a pinworm infection.³ Pinworm transmission is most common via the fecal-oral route, and an infection occurs after the ingestion of pinworm eggs.^1,2 Transmission may also occur via sexual intercourse or contact with contaminated furniture, bedding, clothes, and personal care products. Rarely, transmission may occur when airborne eggs are inhaled and then subsequently swallowed.^2,3

The Life Cycle of Enterobius vermicularis (Pinworm)

After the ingestion of embryonated eggs, the eggs hatch and release the larvae into the duodenum. An ingested embryonated egg develops into an adult pinworm within two to six weeks. After ingestion and hatching, the larvae migrate through the ileum to the cecum, appendix, and colon. The larvae then molt twice, develop into female and male adult worms, attach to the intestinal mucosa, and begin to mate. The male worm dies after mating.³

After mating, the gravid female worm migrates along the colon to the rectum, where contact with air stimulates oviposition. The female deposits the eggs on the perianal skin.^3,4 Every adult female worm can lay up to approximately 17,000 eggs.³ As the female pinworm moves around to lay eggs on the perianal skin, it causes intense itching.⁴ Since the eggs are sticky and surrounded by an adhesive matrix to adhere them to the perianal skin, the eggs can also stick to fingers and fingernails after scratching the perianal area where the eggs are laid. Some eggs can also detach to contaminate surfaces in the environment and clothing.³

The adult female has a lifespan of 37 to 100 days and dies after laying eggs.³ Since the life span of adult pinworms is short, chronic pinworm infections are often caused by repeated cycles of reinfection, including autoinfection.^3,4

Signs and Symptoms of an Enterobius vermicularis (Pinworm) Infection

Infection with Enterobius vermicularis can be asymptomatic, and research suggests that up to 30-40% of cases could be asymptomatic.^2,3

The pathognomonic symptom of enterobiasis in symptomatic individuals of all ages is nocturnal pruritus ani (perianal itching) with inflammation and evidence of scratching in the perianal region. Those with enterobiasis are at increased risk of developing PTSD and anxiety disorders. Signs and symptoms of enterobiasis in children may also include irritability, nausea, vomiting, diarrhea, constipation, insomnia, recurrent cellulitis, loss of appetite and food avoidance, diffuse abdominal pain and tenderness, tenesmus, skin concerns, poor academic performance, nocturnal enuresis, sleep bruxism, and nightmares.^3,5

The gastrointestinal (GI) tract is the primary site of pinworm infestation. However, the pinworms can migrate to other areas. Ectopic sites of infection may include the vagina, cervix, uterus, fallopian tubes, ovaries, lymph nodes, paraovarian tissue, Bartholin glands, salivary glands, nasal mucosa, kidney, gallbladder, bile duct, prostate, bladder, lungs, the inguinal canal, ureter, liver, the peritoneum, retrocecal tissues, and the eyes.³

Rarely, a pinworm infestation can be associated with Loeffler syndrome, bowel obstruction, exacerbation of Sweet syndrome, eosinophilic enterocolitis, eosinophilia, urticaria pigmentosa exacerbation, transverse myelopathy in the setting of antiphospholipid antibody syndrome, intussusception, and reactive arthritis.³

Enterobius vermicularis can also infect the endometrial lining of the uterus to cause endometritis, irregular menstrual cycles, and urinary incontinence.^4,5 Prolonged infection of the female genitourinary tract can result in vulvovaginitis, vaginitis, vulvitis, salpingitis, salpingo-oophoritis, a ruptured tubo-ovarian abscess, chronic pelvic inflammatory disease, infertility, Bartholin’s gland abscess or cyst, vaginal bleeding, oophoritis, or general peritonitis.^3,4

A pinworm infection may lead to urethritis, urinary tract infection, epididymitis, mesenteric lymphadenopathy, sialoadenitis, orchid-epididymitis, mesenteric abscess, keratitis, perianal abscess, and hepatitis. Pinworms can also cause perineal nodules after penetrating the anal mucosa.³ In rare and extreme cases, Enterobius vermicularis may penetrate the submucosa layer of the bowel, leading to death.⁵

The Best Test to Diagnose a Pinworm Infection (Enterobiasis)

Microscopy for direct detection of eggs in stool remains the gold standard and most widely used method for evaluating intestinal helminth infections. However, this technique is not reliable for diagnosing Enterobius vermicularis (pinworm) infections, as the eggs are typically deposited on the perianal skin rather than in the intestinal lumen. Consequently, E. vermicularis eggs are rarely present in stool samples. Serological methods are also not diagnostically useful for enterobiasis.¹

While incidental diagnosis is possible during endoscopy or surgery, the preferred method for diagnosing enterobiasis is the “Scotch tape” or “cellophane tape” test. DiagnosTechs™ offers a convenient Pinworm Detection Test^TM with three sticky paddles designed for easy home collection. To perform the test, the paddle is firmly pressed against the perianal skin immediately upon waking, prior to bathing or using the restroom. The sensitivity of a single collection is approximately 50%, but sensitivity increases to over 90% when samples are collected on three separate mornings.³

After collection, the three paddles are examined under a microscope for the presence of pinworm eggs or adult worms. Visualization confirms the diagnosis of enterobiasis. Because the infection is highly contagious and often asymptomatic, all household or community members should be tested and treated if one individual is diagnosed with a pinworm infection. One study found that multiple individuals were affected in 80% of families with one diagnosed family member.³

Treatment of Enterobiasis (Pinworm Infection)

Maintaining good personal hygiene can prevent infection and reinfection with pinworm. Good personal hygiene includes fingernail clipping, frequent handwashing, and the avoidance of nail-biting, perianal scratching, and sucking on fingers. Handwashing after using the restroom and before meals is especially crucial.³

Since pinworm eggs are sticky and can survive in the environment, launder all linens and wipe down relevant surfaces in the home, school, or other environment during treatment. Please be reassured that enterobiasis is a common health concern in children and is generally benign with proper treatment and preventive measures.³

Naturopathic and pharmaceutical treatment protocols are presented in the document Pinworm Treatment Protocols, available in your Provider Portal.

To place a test order, click here. As a reminder, DiagnosTechs^TM will drop ship test kits directly to your patients. Select this option at the top of the order form.

References:

1. Wendt S, Trawinski H, Schubert S, et al. The Diagnosis and Treatment of Pinworm Infection. Dtsch Arztebl Int. 2019;116(13):213-219. doi:10.3238/arztebl.2019.0213
2. Rawla P, Sharma S. Enterobius Vermicularis. StatPearls [Internet]. August 1, 2023. Accessed August 5, 2025. https://www.ncbi.nlm.nih.gov/books/NBK536974/.
3. Leung AKC, Lam JM, Barankin B, et al. Pinworm (Enterobius Vermicularis) Infestation: An Updated Review. Curr Pediatr Rev. 2025;21(4):333-347. doi:10.2174/0115733963283507240115112552
4. Ng YW, Ng SB, Low JJ. Enterobius vermicularis infestation of the endometrium – a cause of menstrual irregularity and review of literature. Ann Acad Med Singap. 2011;40(11):514-515.
5. Karamitros G, Kitsos N, Athanasopoulos F. A case of enterobiasis presenting as post-traumatic-stress-disorder (PTSD): a curious case of the infection with predominant mental health symptoms, presenting for the first time in the settings of a refugee camp. Pan Afr Med J. 2017;27:111. doi:10.11604/pamj.2017.27.111.12870