Clear Worm in Stool: 6-Year-Old Child
The most likely diagnosis is pinworm (Enterobius vermicularis) infection, which should be treated with albendazole 400 mg as a single oral dose, repeated in 2 weeks, along with treatment of all household members. 1, 2
Why Pinworm is Most Likely
Pinworms are the most common intestinal parasite in children worldwide, particularly affecting those aged 5-14 years, and are frequently visible as small, clear-to-white, thread-like worms in stool. 1, 3 The worms are typically 6-7 mm in length and can appear translucent or whitish. 4
Key Clinical Features to Assess
- Nocturnal perianal itching is the hallmark symptom, though 30-40% of infected children are completely asymptomatic. 1, 2, 3
- Other symptoms may include irritability, weight loss, abdominal pain, or diarrhea. 1
- In girls, vaginal discharge or vulvovaginitis can occur if worms migrate to the genital tract. 1, 4
Diagnostic Confirmation
The "sellotape test" (cellophane tape test) is the gold standard for diagnosis, performed by pressing adhesive tape against the perianal skin first thing in the morning before bathing, then examining it microscopically for eggs. 1, 2 A single test has only 50% sensitivity, but three tests performed on different mornings increase sensitivity to approximately 90%. 3
Important caveat: Stool examination is NOT recommended for pinworm diagnosis because eggs and worms are not consistently passed in stool. 3 If a worm is visualized (as in this case), pathological examination confirms the diagnosis definitively. 3
Treatment Protocol
First-line treatment options (both equally effective): 1, 5, 2
- Albendazole 400 mg as a single oral dose, OR
- Mebendazole 100 mg as a single oral dose
Critical treatment considerations:
- Repeat the dose in exactly 2 weeks to kill newly hatched worms and prevent reinfection. 2, 3
- Treat ALL household members simultaneously, even if asymptomatic, as reinfection rates are extremely high without this approach. 3, 6
- Albendazole and mebendazole are both adulticidal (kill adult worms) and ovicidal (kill eggs), making them superior to alternatives. 3
Prevention of Reinfection
Reinfection is common due to the short life cycle and ease of autoinfection. 3, 7 Essential hygiene measures include:
- Frequent handwashing, especially after bowel movements and before meals. 5, 3
- Clip fingernails short and discourage nail-biting, finger-sucking, and scratching the perianal area. 3
- Wash bedding and underwear in hot water on the day of treatment. 3
Alternative Diagnoses to Consider
If the worm does NOT match pinworm characteristics (i.e., if it's larger, pink/white colored like an earthworm, or segments are visible), consider:
- Roundworm (Ascaris): Pink or white worms resembling earthworms, 15-35 cm long; treat with albendazole 400 mg single dose. 5, 8
- Tapeworm segments: Flat, rectangular segments (proglottids) visible in stool; requires praziquantel 10-25 mg/kg depending on species. 1, 5
However, given the age group and "clear" appearance described, pinworm remains by far the most probable diagnosis. 1, 3