Nikki’s mother brought her to the office because of a number of issues that had been going on for awhile. The young lady is12 years old and usually an active sixth grader—a real “go-getter” according to mom. She is an excellent student who plays soccer and dances four days a week. Her mom states that Nikki has an endless abundance of energy...that is, until a couple of weeks ago.
It seems that Nikki had a “bug” of some sort around a month ago. She had some diarrhea and vomiting which was not too bad according to mom. In fact it affected everyone in the house, and Nikki seemed to have the mildest case. “Ever since then she just has not been the same. She mopes around the house with no energy. Her appetite is the pits, and she complains of her stomach bothering off and on. I’m sure she has lost weight as clothes just hang on her.”
Nikki denied having any real fever. She did have a sore throat about a week and a half ago. There was no cough or respiratory symptoms, but she just felt wiped out. Nikki did admit having some loose stools. “Not really diarrhea,” she said. “Well, maybe it is diarrhea...sort of. My stomach really bothers me at times. I feel bloated, like I have a lot of gas. It’s embarrassing because I will be sitting in class and you can hear my stomach gurgling from across the room”.
Looking at her chart confirmed that she had lost four pounds since the last well-check three months earlier. Her exam was unremarkable with the exception of very hyperactive bowel sounds. One did not need a stethoscope to appreciate them. Mom was relieved to know that Nikki did not have anything clinically that would suggest mononucleosis. “You know that Johnson boy is just getting over mono, and I know you’ve been seeing him a lot lately,” her mom said, to which Nikki blushed and rolled her eyes.
I asked Nikki if she had been camping or hiking recently. They both looked at me with a puzzled expression on their faces. They explained at the same time, “Our family rented a houseboat for a week. But it was over a month ago.” When Nikki was asked if she had been in the water, she said that they had used jet skis, but had to wear wet suits because it was so cold.
The lab tests came back positive for Giardia Iamblia. I had begun treating Nikki even before getting the results, as the history was so classic. She finished her medication without incident, but it took a good two-to-three weeks before she was back to feeling like her normal self.
Giardia Iamblia is an intestinal parasite that infects the intestinal tract of humans. It is probably the most common parasite in the United States, and is acquired by ingesting Giardia cysts in contaminated water. When a person ingests the cysts, they travel to the upper intestinal tract. Four trophozoites are then liberated which attach to the lining of the duodenum and upper small intestine where they take up residence. The cysts are passed into the stool and can remain viable in water for up to two months. Their viability is not felt to be affected by the normal concentrations of chlorine that is used to purify water. It was thought that humans were the only reservoir for Giardia. But it is now believed that dogs and beavers can also become infected. Most lakes, rivers and streams are contaminated with Giardia. Therefore hikers must be mindful of the way drinking water is prepared when camping, and swimmers must be careful where they swim.
Symptoms of Giardiasis usually develop one-to-three weeks after exposure to the parasite. Adults are not affected as severely as children. In fact, the majority of adults with Giardia are without symptoms. One report states, however, 50%-to-80% of children with Giardia did, in fact, have symptoms after an average incubation period of eight days. The symptoms include diarrhea, weight loss, crampy abdominal pain, gassiness and a bloated feeling. The symptoms may be abrupt and severe or they may wax and wane, lasting for months. One may develop secondary lactose intolerance due to the damage to the lining of the intestine. This can cause a protracted course of diarrhea that just never gets better.
Previously it was a challenge to diagnose Giardia. The cysts were not easy to find in a stool specimen because they are not constantly being shed. The old standard used to involve obtaining three separate stool specimens. This increased the yield to around 80%...but was also very costly. Now there is an antigen test that can be done on a single stool specimen that is over 90%-95% sensitive.
The treatment of Giardia has changed over the years due to developing resistance. Twenty years ago, standard treatment included taking Metronidazole for five days. This was extended to seven days, and then recommended to use an increased dose for seven days. More recently this was increased to ten days and after awhile the dose was increased yet again. This has been a problem in children because there is not a liquid preparation, only tablets. A pharmacist has to crush the tablets and make a suspension. But even with different flavoring, taste is a real problem. As a result, compliance is also an issue when a child has to take something three times a day for ten days.
There is a brand new drug out for the treatment of Giardia and it looks to be promising. It is called Alinia. It is a liquid preparation that can be used for infants as young as ten months. The nice thing about this drug is, it is to be taken twice a day for three days. Since it is new, time will tell how successful it will be in the treatment of Giardia.