What is giardiasis?
Giardiasis is an infection of the small intestine caused by Giardia lamblia, also known as Giardia duodenalis or Giardia intestinalis: a single-cell. The disease has diarrhea as the main symptom. Giardiasis is a worldwide one of the most common causes of diarrhea in both humans and animals.
Giardiasis symptoms
Not everyone who has experiencing an infection with Giardia symptoms; patients, which have so suffer from diarrhea, smelly and greasy light colored stools, flatulence, abdominal cramps, nausea and heartburn. The result is often weight loss, weakness, and chronic fatigue.
On the pathogenesis of giardiasis is still little known. Until recently it was thought that the reason was the physical cover of the intestines and competition for nutrients in the duodenum. Nowadays, however, it is assumed that this has no significant role in the pathogenesis. We now know that giardiasis caused by a multifactorial process in which secretory / excretory products of the parasite and the host immune system play a major role. Patients with congenital immune deficiency, such as IgA deficiency, or acquired immunodeficiencies, are more likely to develop a chronic giardiasis.
Because the absorption of food in the small intestine is inhibited by the presence of the parasites, and malnutrition can (in children) growth delay.
Diagnostics
An infection with giardia lamblia is in the clinic usually fixed, by means of microscopy or enzyme linked immunosorbent assay (ELISA). The sensitivity of microscopy when a single sample is examined, is relatively low (50-70%), this is mainly due to the intermittent emission of cysts. To increase the sensitivity by monsters on multiple times to take off, to concentrate and to fixate. When samples are fixed trofozoïeten, as well as cysts be demonstrated. The ELISA is more sensitive than microscopy (+/-98% at single assessment), but optimum results are achieved when these techniques are combined. This involves the collection of stool samples taken on different days, two Fixed microscopically examined and a sample is tested using ELISA. This method is known as the Triple-Faeces-Test (TFT). Different PCR techniques focused on the demonstration of giardia lamblia are in the experimental stage. These techniques can be expected in the future occupy an important place in demonstrating and characterize of giardia lamblia.
Prospects
The disease usually takes a week or two, but can also (much) longer and are interrupted by symptom-free periods. Risk for a chronic course, people with poorly functioning immune system and hypogammaglobulinaemia patients.
Giardiasis treatment
Against the pathogen consist of antibiotics, especially metronidazole and tinidazole. In the vast majority of cases the complaints are thus disappeared after a few days. However, these drugs have troublesome side effects, especially when combined with alcohol.
Epidemiology
Worldwide, giardia lamblia most diagnosed pathogenic Protozoan. It is endemic to, both in countries with a high and with low prosperity. For example, with chlorine dioxide thorough drinking water purification, can do a lot to prevent contamination.
Every year, about 500,000 new infections in the World Health Organization (WHO) reported. In Netherlands is the prevalence of giardia lamblia, in patients with complaints of chronic diarrhea to consult their family doctor, between 8 and 12%.
In individuals without symptoms in the Netherlands a 5% prevalence found Infection occurs by consuming fecal contaminated food or water. Also direct infection between people seems an important role to play, particularly in schools and kindergartens, where children from low ages bunched together. There are several known cases of large-scale outbreaks of giardia lamblia, which are attributed to contaminated water supplies, waste water treatment plants both recreational water facilities. For this reason, carefully monitored in the Netherlands in wastewater treatment plants to the risk that giardia lamblia could be spread. Even smaller-scale outbreaks have been described by contaminated food.
Giardia lamblia is, except in humans, even for globally in other mammalian species. These are largely animals are in close contact with humans. Examples of these are pets such as dogs and cats, and various types of livestock such as cattle, sheep and horses.
The fact that giardia lamblia appears in both humans as well as in the animals referred to above, means that account should be taken of the possibility that giardia lamblia can be a zoonotic parasite. Conclusive evidence for this hypothesis is lacking so far however.