Source: Manual of Ambulatory Pediatrics 2010
SOAP Note – Pinworms
An infestation by intestinal parasite; generally benign; characterized by anal pruritus, especially at night.
I. Etiology
A. Enterobius vermicularis, a 4-mm worm, inhabits rectum or colon and emerges to lay eggs in the skin folds of the anus. Ingested eggs hatch in the duodenum, mature in the small intestine, and reproduce in the cecum. The worms then migrate to the rectum and eventually to the perianal skin where eggs are laid. The eggs become infectious within 2 to 4 hours.
B. The entire cycle from ingestion of eggs to maturation and egg-laying takes 4 to 6 weeks.
II. Incidence
A. The most common parasitic infestation in children in the United States
B. All ages are susceptible.
C. Autoinfection is common.
D. Humans are the only host.
III. Incubation period: 3 to 6 weeks following ingestion of eggs
IV. Communicability: Transmissible through fecal–oral route as long as viable worms are present.
V. Subjective data
A. Perianal pruritus, especially at night
B. Restlessness during sleep
C. Females may complain of pain or itching of genitals.
D. If anus is inspected during the night, ova, or white threadlike worms approximately 0.5 to 1.0 cm in length, may be seen.
VI. Objective data
A. Rectal excoriation may be present.
B. Vulva may be inflamed.
C. Pinworms or ova are almost never observed in the office.
VII. Assessment: Diagnosis is made by microscopic identification of ova on transparent Scotch tape that has been applied to the perianal area and placed on a glass slide. Prior to microscopic examination, place a drop of toluene between tape and slide.
VIII. Plan
A. Vermox chewable tablets: 100 mg PO, one time, for all ages over 2 years
B. Treat all family members simultaneously except pregnant women and children under 2 years of age.
C. Sitz baths for rectal or vulva irritation
D. Desitin to perianal area if irritated from scratching
E. Retreatment: Vermox removes young larvae and adult worms. It does not destroy eggs; therefore, retreatment can be done in 2 to 3 weeks before the worms originating from eggs at time of initial treatment progress to egg-laying phase.
IX. Education
A. Teach parent how to prepare slide.
1. Use clear Scotch tape wrapped around finger, sticky side out.
2. Spread buttocks and tap firmly around perianal area during the night or in the early morning, preferably before child gets up, but at least before toileting.
3. Apply tape, sticky side down, to clear glass slide.
4. Note: Slides for diagnosis may be purchased, but above method is less expensive and works just as well.
B. Communicability is high.
C. Transmitted directly by autoinfection: Child scratches anus, gets the eggs under the fingernails, and then puts fingers in mouth. Transmitted also by handling contaminated clothing and linen.
D. Pinworms are contracted through human contact only; they are not worms from dogs or cats.
E. Eggs remain viable in humid environment for several days.
F. Stress personal hygiene to avoid autoinfection.
1. Bathe daily in the morning to remove eggs.
2. Wash hands after toileting and before eating.
3. Keep fingernails short and clean.
4. Wear tight cotton underpants.
5. Change underpants twice a day, in the early morning and at bedtime.
6. Change bedding nightly.
7. Laundry should be washed in hot water and dried in a hot dryer. Avoid shaking bedding and clothing prior to laundering. If eggs become airborne they can be inhaled and swallowed.
G. Disinfect bathroom daily.
H. Perianal itching is caused by gravid worm crawling out of anus and laying eggs. Vaseline applied to anus may prevent or relieve itching.
I. Vermox
1. Side effects are abdominal pain and diarrhea.
2. Tablet may be chewed, swallowed, or crushed and mixed with food.
3. Vermox has a 95% cure rate.
J. Recurrences are common, particularly in large families and dormitories.
K. Reassure that course is benign and infestation is easily treated. Pinworm infestation can be very upsetting to parents, and they may go to extremes in environmental control.
X. Follow-up
A. Not generally indicated
B. Call or return to office in 3 weeks if symptomatic.
C. Treatment with Vermox may need to be repeated.
XI. Complications
A. Vulvovaginitis from migration of worms to vagina
B. Secondary bacterial infection from excessive scratching
C. Occasionally, symptoms of appendicitis
XII. Consultation/referral
A. Pregnant women
B. Children under 2 years of age