Ultrasound Shows Parasitic Worms Moving in Man's Stomach Were the Cause of His Diarrhea and Vomiting

When you have symptoms like abdominal pain, diarrhea, and vomiting, it's easy to assume you caught some kind of stomach bug. But, for one man, these were signs that he had an intestinal parasite.

The 20-year-old man and his story ended up in a case report in The New England Journal of Medicine, published Saturday. The report details how the man, who has not been publicly identified, went to the ER in New Delhi, India, after a day of having intense gastrointestinal symptoms. He was otherwise healthy, but a blood test showed that the man had high levels of white blood cells. (White blood cells, in case you're not familiar with them, are part of the immune system and help your body fight off infections and other diseases. Having a high white blood cell count can indicate an infection, per Medline Plus.) He also had higher-than-normal levels of the blood protein hemoglobin, which can also be a tip-off that a person is sick.

So, doctors decided to look inside the man's body. They conducted an ultrasound of his inferior vena cava, a large vein in his abdomen, to check the level of fluid in his veins. But, while they were at it, they just happened to catch something freaky happening in his stomach. The case report authors wrote that they saw a "tubular" structure "that moved with a curling motion" inside his stomach. (There's video of the ultrasound, and it clearly shows a worm-like creature slowly squirming around in the man's stomach.)

The man was asked to give a stool sample, and doctors found fertilized eggs from the intestinal parasite Ascaris lumbricoides in his poop. He was eventually given IV fluids, a single dose of the anti-parasitic drug albendazole, and discharged him from the hospital after a day.

What is Ascaris lumbricoides?

Ascaris lumbricoides, which is also referred to as just Ascaris, is a parasitic worm—one that can grow up to 14 inches long— that lives in the intestine, the Centers for Disease Control and Prevention (CDC) explains. Ascaris eggs come out in the poop of an infected person and, if a person with an Ascaris infection (aka, ascariasis) poops outside or if their feces is used as fertilizer, the worm eggs can be deposited in the soil. From there, they can be accidentally ingested by someone who puts their hands or fingers that have contaminated dirt on them in their mouth, or by eating vegetables or fruits that have not been carefully peeled, washed, or cooked, the CDC says.

How common are Ascaris infections?

If you look at Ascaris infection cases on a global scale, it's a pretty common—anywhere from 800 million to 1.2 billion people have these worms in their intestinal tract, the CDC says. But its most commonly found in places where access to personal hygiene and proper sanitation practices aren't available, as well as in places where human feces is used as fertilizer.

That's why this infection is "very rare in the U.S.," Richard Watkins, M.D., an infectious disease physician in Akron, Ohio, and a professor of medicine at the Northeast Ohio Medical University, tells Health. That said, it's a good idea to at least be aware that this is a thing when you travel. "Travelers to endemic areas should take precautions," Dr. Watkins says. That includes washing your hands well with soap and water before eating or touching your mouth, and only eating foods that have been properly prepared.

What are the symptoms of an Ascaris infection?

People who have ascariasis don't usually have symptoms, the CDC says. But, if they do show signs of the infection, they're often minor. Those can include:

• Intestinal discomfort
• Intestinal pain

In some situations, a person may develop a cough due to the worms migrating in the body, the CDC says. And, in more severe cases, ascariasis can block the intestines and slow the growth of children.

How is an Ascaris infection usually treated?

Treatment usually involves the use of anti-parasitic medications like albendazole or mebendazole, per the CDC. Typically, someone will be treated for one to three days, and will recover just fine.

As for the man with the parasites in his stomach, he was seen for a follow-up visit two weeks after his appointment. At that time, he said he was feeling well and had passed the worms in his poop.