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PinWorm
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Pinworms “threadworms”
What you need to know
Age
Signs of infestation
Perianal itching
Appearance of worms
Other symptoms
Duration
Recent travel abroad
Other family members affected
Medication
When to refer
Infestation other than threadworm suspected
Recent travel abroad
Medication failure
Pregnancy
If the patient with a pinworm infection develops:
o Fever or abdominal pain. These symptoms may be a sign of complications of
pinworm infection.
o Redness, tenderness, or swelling in the genital area. This may be a sign of skin
infection.
o Itching in the genital area or vagina. This may be a sign of vaginal pinworm
infection.
o Pain when urinating, frequent or urgent urination, or lack of control of urination.
These may be signs of pinworm infection of the urinary tract.
High risk patients:
International students
Travelers
Migrant workers
Refugees
Homeless persons
Children who have been adopted from a foreign country
Individuals who eat some raw foods such as fish, sushi,
Pinworm is more common than other helminthes because it is not spread via
waterborne routes
Pinworm species:
Enterobius vermicularis
It is the most common helminth infestation affecting humans throughout the
temperature climates of the world
Epidemiology
Enterobiasis (infestation with pinworm) exhibits a strong age stratification:
Children aged 5-14 yo suffer the highest rates “60-100%” because of the methods ova
are transmitted
Adults 16%
Studies show that whites are at higher risk than blacks
Present in all parts of the world, urban and rural areas
Etiology
After the ova reaches the stomach, gastric acids dissolve the outer covering to release
minute larvae, the larvae hatch in the duodenum, maturing in 15 to 28 days.
Worms live and mate throughout the length of the bowel, attached to the mucosal of
the ileum, cecum and ascending colon or vermiform appendix.
During the night, pregnant females exit the anus to lay eggs, depositing as many as
10,000 ova on the perianal skin.
After laying eggs female pinworms usually die, although they may reenter the individual.
The average pinworm life span is 37 – 93 days
With in 6 hrs after being deposited, the ova or eggs become infective. They have thick
walls that resist desiccation, allowing them to remain infective for up to 20 days.
They are sticky, adhere to various surfaces
Scratching the perianal skin can loosen the eggs allowing them to enter the
environment and contamination happen
Transmission of pinworm
Three methods
• Finger to mouth
• Inhalation (some, of the ova deposit in the oropharynx, from which they are
subsequently swallowed)
• Retroinfection
Manifestations of pinworm infestation
Pinworms produce symptoms through three mechanisms:
• Mechanical stimulation and irritation
• Allergic reactions
• Rare, accidental movement of the pinworm from its preferred location in the
bowel to ectopic sites (found outside of the normal location)
Diagnosis of pinworm infestation
Check after one hr of going to bed by flashlight
Procedure to give definite diagnosis
Treatment guidelines
Fingernails should be cut short and children should be cautioned against
scratching the perianal area
Children must be warned to keep their fingers out of the mouth at all time
during treatment
During the week following treatment, all family members must wear cotton
underpants that are changed twice daily and washed in hot, soapy water
Children sleeping garments “e.g. Pajamas, underpants” should cover the anus to
help prevent scratching this area
Daily showers are less likely to promote reinfection than bathtub soaking
The toilet seat must be cleaned after each family member uses it
Furnishings, toys, should be disinfected with disinfectants
Cleaning the whole house in required
Linens and clothing should be washed using the hottest water available
These measures are important because medication only kills the mature worms,
if eggs or larvae reinfect the body, infection come again. So ancillary measures are of
importance.
Treatment
OTC
Pyrantel Pamoate
• Suspension
• The only approved nonprescription ingredient
• Eradicates pinworm through depolarization of muscle, thereby paralyzing the
pinworm’s contrsctile hold on the intestinal wall. As the worm fall away, they are carried
out of the patient through perstalsis in the feces. Paralyzing the helminths
• Pregnancy category C
• Pregnant women and children under the age of 2 should not use the medication
without first consulting a health professional because the medication has not been
tested for safety in these groups.
• Dose; 11mg/kg/dose
• Treat all family members
• S.E. nausea, vomiting, abdominal cramps, diarrhea
• Poor oral absorption
• Dose; 11mg/kg/day as a single dose
• Dose should be repeated in 2 weeks
• Morning parameters; stool for the presence of eggs, worms, and occult blood
• Serum AST, ALT
• May mix drug with milk or fruit juice
• Strict hygiene is essential to prevent reinfection
• Dosage forms; Caps 180 mg, Liq 50mg/ml, Susp 50mg/ml
• The dose of pyrantel pamoate given is based on the person's weight. Two doses
are usually given about 14 days apart (as long as no side effects were noted after the
first dose). More than the correct dose should not be given at any time.
• Pyrantel pamoate kills adult pinworms. It does not kill pinworm eggs
• Side effects of pyrantel pamoate are not very common. Side effects may include:
Nausea, vomiting, abdominal cramps, and diarrhea. These are the most commonly seen
side effects. Headache, dizziness, and sleeplessness. Rash.
• If side effects develop after the initial dose, a second dose (normally taken in
about two weeks) should not be taken without talking to the pharmacist
• Because pinworm eggs can survive for two weeks after treatment with pyrantel
pamoate, reinfection can occur. Treatment with a second dose is usually recommended.
• Undergoes partial hepatic metabolism, things to be considered in case of liver
failure
Prescription medications
mebendazole (Vermox)
thiabendazole (Mintezol)
Prevention of pinworm infestation
• Always clean hands after defecation and prior to eating
• If possible have children sleep in separate beds to prevent transfer to siblings
• Use good hygiene practices in bathrooms to prevent the transfer of eggs from
cups, toothpaste….etc
• Eggs are not killed by chlorination of water in swimming pools, so take care
What you need to know
Age
Signs of infestation
Perianal itching
Appearance of worms
Other symptoms
Duration
Recent travel abroad
Other family members affected
Medication
When to refer
Infestation other than threadworm suspected
Recent travel abroad
Medication failure
Pregnancy
If the patient with a pinworm infection develops:
o Fever or abdominal pain. These symptoms may be a sign of complications of
pinworm infection.
o Redness, tenderness, or swelling in the genital area. This may be a sign of skin
infection.
o Itching in the genital area or vagina. This may be a sign of vaginal pinworm
infection.
o Pain when urinating, frequent or urgent urination, or lack of control of urination.
These may be signs of pinworm infection of the urinary tract.
High risk patients:
International students
Travelers
Migrant workers
Refugees
Homeless persons
Children who have been adopted from a foreign country
Individuals who eat some raw foods such as fish, sushi,
Pinworm is more common than other helminthes because it is not spread via
waterborne routes
Pinworm species:
Enterobius vermicularis
It is the most common helminth infestation affecting humans throughout the
temperature climates of the world
Epidemiology
Enterobiasis (infestation with pinworm) exhibits a strong age stratification:
Children aged 5-14 yo suffer the highest rates “60-100%” because of the methods ova
are transmitted
Adults 16%
Studies show that whites are at higher risk than blacks
Present in all parts of the world, urban and rural areas
Etiology
After the ova reaches the stomach, gastric acids dissolve the outer covering to release
minute larvae, the larvae hatch in the duodenum, maturing in 15 to 28 days.
Worms live and mate throughout the length of the bowel, attached to the mucosal of
the ileum, cecum and ascending colon or vermiform appendix.
During the night, pregnant females exit the anus to lay eggs, depositing as many as
10,000 ova on the perianal skin.
After laying eggs female pinworms usually die, although they may reenter the individual.
The average pinworm life span is 37 – 93 days
With in 6 hrs after being deposited, the ova or eggs become infective. They have thick
walls that resist desiccation, allowing them to remain infective for up to 20 days.
They are sticky, adhere to various surfaces
Scratching the perianal skin can loosen the eggs allowing them to enter the
environment and contamination happen
Transmission of pinworm
Three methods
• Finger to mouth
• Inhalation (some, of the ova deposit in the oropharynx, from which they are
subsequently swallowed)
• Retroinfection
Manifestations of pinworm infestation
Pinworms produce symptoms through three mechanisms:
• Mechanical stimulation and irritation
• Allergic reactions
• Rare, accidental movement of the pinworm from its preferred location in the
bowel to ectopic sites (found outside of the normal location)
Diagnosis of pinworm infestation
Check after one hr of going to bed by flashlight
Procedure to give definite diagnosis
Treatment guidelines
Fingernails should be cut short and children should be cautioned against
scratching the perianal area
Children must be warned to keep their fingers out of the mouth at all time
during treatment
During the week following treatment, all family members must wear cotton
underpants that are changed twice daily and washed in hot, soapy water
Children sleeping garments “e.g. Pajamas, underpants” should cover the anus to
help prevent scratching this area
Daily showers are less likely to promote reinfection than bathtub soaking
The toilet seat must be cleaned after each family member uses it
Furnishings, toys, should be disinfected with disinfectants
Cleaning the whole house in required
Linens and clothing should be washed using the hottest water available
These measures are important because medication only kills the mature worms,
if eggs or larvae reinfect the body, infection come again. So ancillary measures are of
importance.
Treatment
OTC
Pyrantel Pamoate
• Suspension
• The only approved nonprescription ingredient
• Eradicates pinworm through depolarization of muscle, thereby paralyzing the
pinworm’s contrsctile hold on the intestinal wall. As the worm fall away, they are carried
out of the patient through perstalsis in the feces. Paralyzing the helminths
• Pregnancy category C
• Pregnant women and children under the age of 2 should not use the medication
without first consulting a health professional because the medication has not been
tested for safety in these groups.
• Dose; 11mg/kg/dose
• Treat all family members
• S.E. nausea, vomiting, abdominal cramps, diarrhea
• Poor oral absorption
• Dose; 11mg/kg/day as a single dose
• Dose should be repeated in 2 weeks
• Morning parameters; stool for the presence of eggs, worms, and occult blood
• Serum AST, ALT
• May mix drug with milk or fruit juice
• Strict hygiene is essential to prevent reinfection
• Dosage forms; Caps 180 mg, Liq 50mg/ml, Susp 50mg/ml
• The dose of pyrantel pamoate given is based on the person's weight. Two doses
are usually given about 14 days apart (as long as no side effects were noted after the
first dose). More than the correct dose should not be given at any time.
• Pyrantel pamoate kills adult pinworms. It does not kill pinworm eggs
• Side effects of pyrantel pamoate are not very common. Side effects may include:
Nausea, vomiting, abdominal cramps, and diarrhea. These are the most commonly seen
side effects. Headache, dizziness, and sleeplessness. Rash.
• If side effects develop after the initial dose, a second dose (normally taken in
about two weeks) should not be taken without talking to the pharmacist
• Because pinworm eggs can survive for two weeks after treatment with pyrantel
pamoate, reinfection can occur. Treatment with a second dose is usually recommended.
• Undergoes partial hepatic metabolism, things to be considered in case of liver
failure
Prescription medications
mebendazole (Vermox)
thiabendazole (Mintezol)
Prevention of pinworm infestation
• Always clean hands after defecation and prior to eating
• If possible have children sleep in separate beds to prevent transfer to siblings
• Use good hygiene practices in bathrooms to prevent the transfer of eggs from
cups, toothpaste….etc
• Eggs are not killed by chlorination of water in swimming pools, so take care