Tests and diagnosis

By Mayo Clinic Staff

In heavy infestations, it's possible to find worms after you cough or vomit, and the worms can come out of other body openings, such as your mouth or nostrils. If this happens to you, take the worm to your doctor to identify it and prescribe the proper treatment.

Stool tests

Mature female ascariasis worms in your intestine begin laying eggs. These eggs travel through your digestive system and eventually can be found in your stool.

To diagnose ascariasis, your doctor will examine your stool for the microscopic eggs and larvae. But eggs won't appear in stool until at least 40 days after you're infected. And if you're infected with only male worms, you won't have eggs.

Blood tests

Your blood can be tested for the presence of an increased number of a certain type of white blood cell, called eosinophils. Ascariasis can elevate your eosinophils, but so can other types of health problems.

Imaging tests

  • X-rays. If you're infested with worms, the mass of worms may be visible in an X-ray of your abdomen. In some cases, a chest X-ray can reveal the larvae in your lungs.
  • Ultrasound. An ultrasound may show worms in your pancreas or liver. This technology uses sound waves to create images of internal organs.
  • CT scans or MRIs. Both types of tests create detailed images of your internal structures, which can help your doctor detect worms that are blocking ducts in your liver or pancreas. CT scans combine X-ray images taken from many angles; MRI uses radio waves and a strong magnetic field.
April 23, 2015

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