Giardiasis

GIARDIASIS

Giardiasis, an illness that affects the digestive tract, is caused by a microscopic parasite called Giardia lamblia. The parasite attaches itself to the lining of the small intestines in humans, where it sabotages the body's absorption of fats and carbohydrates from digested foods. Giardia infection is marked by abdominal cramps, bloating, nausea and bouts of watery diarrhea.

Giardia infection is a waterborne infection and can be caused by parasites found in backcountry streams and lakes, as well as in municipal water supplies, swimming pools, whirlpool spas and wells. Giardia infection can also be transmitted through food and person-to-person contact.

Giardia infections usually clear up within a few weeks. But you may have intestinal problems long after the parasites are gone. Several drugs are generally effective against giardia parasites, but not everyone responds to them. Prevention is your best defense.

Signs and Symptoms

• abdominal cramps
• large amounts of intestinal gas
• an enlarged belly from the gas
• loss of appetite
• nausea and vomiting
• Watery, sometimes foul-smelling diarrhea that may alternate with soft, greasy stools
• Fatigue or malaise
• Abdominal cramps and bloating
• Belching gas with a bad taste
• Weight loss

Causes

Swallowing contaminated water 

Eating contaminated food

Person-to-person contact 

Complications

• Dehydration. 
• Often a result of severe diarrhea, dehydration occurs when the body doesn't have enough water to carry out its normal functions.
• Failure to thrive.
•  Chronic diarrhea from giardia infection can lead to malnutrition and harm children's physical and mental development.
• Lactose intolerance. 
• Many people with giardia infection develop lactose intolerance — the inability to properly digest milk sugar. The problem may persist long after the infection has cleared.

Prevention

• Drink only from water supplies that have been approved by local health authorities.
• Bring your own water when you go camping or hiking, instead of drinking from sources like mountain streams.
• Wash raw fruits and vegetables well before you eat them.
• Wash your hands well before you cook food for yourself or for your family.
• Encourage your kids to wash their hands after every trip to the bathroom and especially before eating. If someone in your family has giardiasis, wash your hands often as you care for him or her.
• Have your kids wash their hands well after handling anything in "touch tanks" in aquariums, a potential source of giardiasis.
• Have your water checked on a regular basis if it comes from a well.
• Practice safer sex.:-If you engage in anal sex, use a condom every time. Avoid oral-anal sex unless you're fully protected
• Keep your mouth closed. Try not to swallow water when swimming in pools, lakes or streams

Giardiasis  Diagnosis  Tests

Stool exam

• The most common way to diagnose giardiasis is by the visualization of theGiardia cysts by experienced laboratory professionals. The cysts are detected 50% to 70% of the time in the first stool specimen examined. Over 90% of the time the cysts are detected after three stool specimens have been examined. So more than one specimen may be required.
• Another method of diagnosis that is commonly used as a screening tool in outbreaks or in daycare centers is antigen assay of stool. This method detects a certain protein found in the wall of Giardia. A stool sample is mixed with a solution that detects the cysts in the stool.

String test

• The string test involves swallowing a fuzzy string enclosed in a gelatin capsule. The free end of the string is taped to the person's cheek. Once swallowed, the string collects secretions and mucus from the small bowel. Four hours later the string is pulled back out and examined for organisms.

Aspiration and biopsy

• This is the most invasive method of diagnosis. After passage of a small telescope through the person's mouth and stomach into the small bowel, the doctor removes a small amount of tissue for examination. This method is reserved for difficult cases in which the cause of diarrhea cannot be determined using other methods. It allows for visualization of all abnormalities of the small intestine, which may cause diarrhea including giardiasis.                                                                                                 

Treatment

Giardiasis Medications

Medications are used effectively to treat giardiasis.

Metronidazole (Flagyl)

• This is the most common and most often recommended drug to treat giardiasis.
• Treatment is 80% to 95% effective with these pills given 3 times a day for 5 days.
• SSide effects may include nausea, vomiting, headache, dry mouth, or a metallic taste in the mouth. Urine may turn dark or reddish-brown. Metronidazole brings on nausea and vomiting when alcohol is consumed while on the medication. Avoid alcohol 24 hours before starting the drug and for 48 hours after the last dose.

Quinacrine

• Treatment is 90% effective with these pills given over 5 days. Side effects may include nausea, vomiting, yellow skin and eyes, dark urine, and a rash.

Nitazoxanide (Alinia)

• Nitazoxanide is available in liquid form and must be taken with food. Side effects may include stomach pain, diarrhea, vomiting, or headache.

 Giardias in pregnancy :-

Pregnant women with giardiasis are treated somewhat differently because of the possible risk to the fetus by some of the medications.

• If the disease is mild and dehydration can be avoided, treatment may be postponed until after delivery.
• If treatment is necessary, paromomycin may be used but is less effective. The effects of metronidazole on the fetus appear to be minimal and occur mostly in the first trimester.
• If therapy is necessary, metronidazole is probably safe to use in the second and third trimesters.