Giardiasis (lamblia) In Adults - Signs, Symptoms And Treatment

2024 Author: Josephine Shorter | [email protected]. Last modified: 2024-01-07 17:49

Giardiasis in adults

What is giardiasis?

Giardiasis is an invasive disease caused by protozoal parasites and is characterized by damage to the small intestine. The main manifestations of giardiasis are allergic and pathological neurological reactions.

The causative agent of giardiasis is the simplest flagellar microorganism - lamblia (Giardia). About 40 species of lamblia are known to modern science, but only Lamblia interstinalis parasitizes in the human intestine.

This protozoal microorganism exists in the form of a cyst and in the form of vegetation. Vegetative lamblia has a pear-shaped shape, somewhat reminiscent of a human face with a strained smile. Giardia does not reach more than 24 microns in length, and 12 microns in width, so they are visible only under a microscope.

On the ventral side of the parasite there is a suction disc, which is used to attach to the villi lining the human intestine. Giardia feed on the entire surface of the body, absorbing the substances necessary for their vital activity.

In the form of vegetation, Giardia is very active. Flagella help them in this; the parasite has 4 pairs of them. Outside the human body, vegetative forms are not capable of long-term existence and die in a few hours.

After the parasites enter the human intestine, lamblia begins to divide, forming a new vegetation and cyst. Cysts come out together with the feces of the patient. Unlike vegetation, cysts have good environmental resistance. They retain their viability without a human body for 18 days or more in water, and with sufficient humidity they live for about 4 days. Cysts do not respond to chlorine treatment, but do not tolerate drought. Without sufficient moisture, the cysts die within a few hours.

Giardia lead an independent lifestyle, fully meeting their needs at the expense of the host's body. Giardiasis is ubiquitous. Most of the carriers of this protozoal infection live in Latin America, Africa and Central Asia. For the first time, the causative agent of the disease was discovered in human stool in 1684 by Anthony van Leeuwenhoek, and the scientist D. F. Lambl described the parasite in detail in 1859. This microorganism was named after him.

Animals, along with humans, are prone to giardiasis. This parasitic infestation is found in rabbits, dogs, cats, rodents, cattle and other mammals. A person most often becomes infected from another person who secretes lamblia cysts into the external environment, but the possibility of infection from animals is not excluded.

Already 9-22 days after the primary invasion, a person becomes dangerous to others, since with feces he begins to release cysts of parasites ready for infection into the external environment. Only 1 g of feces can contain 23 million parasite cysts, but the average number of cysts per 1 g of feces is 1.8 million. Moreover, in order for an infection to occur, from 1 to 10 cysts can enter the human gastrointestinal tract. Under these conditions, the risk of invasion will range from 10-30%.

Content:

• Giardiasis statistics
• Causes of infection with giardiasis
• Are lamblia transmitted?
• Giardiasis symptoms
• Consequences of giardiasis
• Diagnostics
• Giardiasis treatment
• Treatment regimens for giardiasis
• Prevention of lamblia in adults
• Which doctor treats giardiasis?

Giardiasis statistics

More than 140 thousand cases of giardiasis are registered in Russia every year. The number of adults from this figure is about 30%. The disease is dangerous primarily because it has an asymptomatic course, and the clinical signs that occur in an adult are not specific. Often giardiasis is hidden under the guise of biliary dyskinesia, under chronic enteritis and other pathologies of the gastrointestinal tract.

The mechanism of transmission of parasitic infection is fecal-oral. Routes of transmission - through hands, through water, through food, seeded with cysts of parasites. Certain insects, in particular flies, can carry lamblia cysts.

The prevalence of giardiasis is explained by the high number of parasite cysts in most environmental objects:

• There are 4 to 30 cysts per 1 cubic meter of water in open reservoirs.
• For 1 liter of wastewater that has not been treated, there are up to 1091 cysts.
• For 1 liter of treated wastewater that will be discharged into open water bodies, there are from 10 to 35 cysts.
• For 1 kg of soil in preschool educational institutions located in unanalyzed settlements, there are up to 112 cysts (11-22% of all studied soils).

• In 6% of cases, cysts were found in washes from door handles in kindergartens, in 3% in washes from children's hands, in 2% in washes from children's pots, and in 0.2% in washes from toys.

Cysts remain viable in water from 15 to 70 days, in feces they live from 2 hours to a day. If cysts enter open water bodies, then at temperatures from 2 to 22 ° C they can live for about 3 months. In the sea, cysts retain the ability to invade for 47 days.

However, cysts are not resistant to heat and they die instantly when boiled. As for food, on fruits, the parasite cysts are able to remain viable for 6 hours, in dairy products they can live up to 12 days, and sometimes up to 112 days.

In various countries around the world, outbreaks of giardiasis have been reported due to drinking untreated water that has not been properly treated at plumbing facilities. For example, a similar situation was observed in America, Egypt, and Sweden.

In most preschool educational institutions, children become infected through dirty hands. The source of the spread of giardiasis is other children, as well as staff.

Do not exclude the possibility of parasite infection through food. Cysts can get on ready-made food products from the hands of those people who have come into contact with them. Or, the infection occurs when eating poorly processed fruits, vegetables, herbs, etc.

Causes of infection with giardiasis

Giardiasis is caused by an intestinal parasite called Lamblia intestinalis.

Giardia multiply in the human small intestine, in those places where they accumulate most. The way of reproduction is continuous pairwise division of vegetative individuals. The speed of this process is very high and averages 20 minutes, as a result, the intestines are colonized by parasites quite quickly.

The activity of lamblia and the rate of their reproduction directly depends on the state of the human digestive system. The number of individuals sharply decreases during fasting and when the patient eats a sufficient amount of protein food. When carbohydrate food enters the body, on the contrary, there is insufficient secretion of bile into the intestinal lumen, which stimulates the growth and reproduction of parasites.

The more active the processes of parietal digestion in the intestine, the faster Giardia begins to divide, which explains the high prevalence of invasion among children, compared with the adult population. Favorable conditions for the existence of the parasite in the intestine is the reduced acidity of gastric juice.

The source of infection is always a sick person. Moreover, he himself can be a carrier of lamblia, and he will not experience symptoms of the disease at all. A person becomes contagious about 8-12 days after the invasion. The incubation period in some cases can be shorter, especially with massive infestation with lamblia.

Cysts are released into the external environment in waves. The pause between this process can be from 1 to 17 days. If a person was infected once, and subsequent reinfection does not occur, then he will remain infectious for 6 months.

From the point of view of maximum infectiousness, the most dangerous is the patient whose symptoms of giardiasis have subsided. During this period, intestinal motility is normalized, and favorable conditions are created for the reproduction of parasites.

One gram of faeces can contain about 1.8 million cysts capable of infestation. And in order for the infection to occur, it is enough to swallow only 10 cysts.

The transmission mechanism of lamblia is fecal-oral. Ways of spread of infection: food, contact, household and water.

Most often, the waterway of the spread of giardiasis leads to massive outbreaks of infection. Infection is not excluded when visiting the pool, when swimming in open water. Giardiasis can be transmitted by eating food contaminated with the parasite's cysts. There are known cases of infection during sexual intercourse between homosexual men.

There is a high risk of transmission of giardiasis under the following conditions:

• Lack of personal hygiene. First of all, this concerns poor-quality and untimely hand washing after visiting public places, the toilet and before eating.
• Poor processing of food that is eaten raw.
• Drinking unboiled water, especially from open natural sources. Giardia can be found in any water, including spring water.
• Poor sanitary living conditions, presence of insects in the house. Flies and cockroaches, which are spreading infections, are especially dangerous in this regard.
• Possible infection with giardiasis from invasive animals: dogs, guinea pigs, cats, etc.

Adults of the following professions are more susceptible to invasions:

• Employees of educational institutions (kindergartens, schools).
• Medical workers (laboratory assistants).
• Vacuum trucks.

Risk factors for developing giardiasis in adults:

• A large amount of carbohydrate foods in the diet.
• Insufficient intake of protein foods and foods with plant fiber (vegetables, fruits, cereals).
• Decreased stomach acidity.
• Impaired immunity.
• Long-term treatment with antibacterial drugs, which leads to bacterial overgrowth in the intestine. This environment is favorable for the existence of lamblia.
• Addiction.

In the Russian Federation, the disease is most often recorded in the spring (April and May), as well as in the summer. The least cases of giardiasis are observed in November and October.

Over the years, the danger of giardiasis has been greatly underestimated. Modern scientists have no doubts that parasites pose a threat to human health. Therefore, lamblia in adults must be diagnosed and treated in a timely manner.

The entrance gate for parasites is the upper small intestine. There, mature cysts lose their protective shell and become vegetative individuals. One cyst gives 2 trophosites. With the help of flagella, they move along the intestinal mucosa, finding comfortable conditions for their existence.

After attachment to the villi of the intestine, the vegetative forms begin to divide. Organ colonization occurs very quickly. Only one square centimeter of the intestine can contain up to 1 ml of individuals. The maximum number of lamblia occurs in the upper part of the small intestine. It is here that parasites have optimal conditions for accessing the spaces between the villi, from which they absorb carbohydrates, fats, proteins, mineral salts and other nutrients. In later periods, lamblia descends into the middle and finished parts of the small intestine.

Those vegetative forms of lamblia that have not attached to the villi descend into the large intestine, where they become cysts. After that, the cysts absorb the flagella and are covered with a protective sheath. This process is maximally facilitated under the condition of normal intestinal peristalsis. If it is accelerated, which is observed with diarrhea, the vegetative forms of lamblia do not have enough time to form full-fledged cysts, and they go out into the environment insufficiently protected. As it was said, such vegetation perishes very quickly outside the human body.

For a long time, there was confidence that lamblia are able to parasitize in the biliary tract. However, it has been proven that bile in high concentrations is harmful to these parasites. They lose their viability in a few seconds.

Factors that contribute to massive outbreaks of giardiasis among the population are:

• Faecal pollution of the environment;
• High crowding of people;
• Low level of formation of sanitary and hygienic skills among the population;
• Insufficient or low-quality treatment of drinking water before it enters the water supply system.

Naturally, the risks of invasion for an adult increase if one or more children under the age of 10 live in the house.

Are lamblia transmitted?

• Is Giardia spread from person to person? Giardia is spread from person to person.
• Are Giardia transmitted through kissing, saliva? Transmission of lamblia through kissing is theoretically possible, provided that parasite cysts are present in the saliva of a person during kissing.
• Is Giardia spread from cats to humans? Transmission of lamblia from cats to humans is possible.
• Can Giardia be seen in feces? It is impossible to see lamblia in the feces on your own, since their size is very small. Therefore, parasites in stool can only be visualized under a microscope.

Giardiasis symptoms

Giardiasis symptoms are very often absent altogether. The asymptomatic course of the disease is observed in 65% of patients. If the clinical picture manifests itself vividly, then most often this is due either to massive invasion, or to disruption of the human immune system, or to the ingestion of individual strains of infection with high virulence into the body. For example, people with HIV have a much more severe illness than healthy patients. The periods of remission are followed by frequent periods of exacerbation.

The following classification of giardiasis is considered to be the most complete:

• Asymptomatic carriage of giardiasis

• Severe symptoms of giardiasis. Severe symptoms of the disease include:

  1. The defeat of the intestine with enteritis, enterocolitis, duodenitis and dyskinesia of the duodenum (intestinal form of the disease).
  2. Hepatobiliary form in which the symptoms of cholecystitis and biliary dyskinesia come to the fore.
  3. Giardiasis as a concomitant disease.

Based on the study of the symptoms of giardiasis in people of different age groups, T. L. Zalipaeva identified the following main syndromes of the disease:

• Dyspeptic syndrome, which is the leading one and is present in the clinical picture in 81.5% of all patients.
• Pain syndrome, which is inherent in 76.9% of all infected.
• Astheno-neurotic syndrome with increased fatigue, irritability and headaches. Similar symptoms are observed in 64.8% of patients.
• Allergic reactions of the body. Most often, patients have atopic dermatitis. This syndrome occurs in 15.7% of cases.

It is noted that such syndromes may be present in any of the listed clinical forms of giardiasis. As for laboratory data, with giardiasis in 31.5% of patients, an increase in the number of eosinophils by 5-7% is observed.

Symptoms of giardiasis in the acute stage

For the acute stage of giardiasis, the following symptoms are characteristic:

• Nausea, lack of appetite, frequent belching.
• Bloating, flatulence, rumbling in the intestines, profuse gas.
• Weight loss.
• In the area of the right hypochondrium and in the umbilical zone, painful sensations arise. In this case, pain in the navel is noted by every second patient, and about 15% of people indicate pain in the right hypochondrium. Painful sensations are very often associated with food intake, so they are not associated with giardiasis.
• A bitter or sour taste appears in the mouth.
• Diarrhea may develop. In this case, the chair becomes more frequent, it can happen from 3 to 5 times a day. If at the beginning of the acute period the character of the stool is liquid and watery, then later it thickens and becomes greasy.
• Salivation increases.
• Rapid fatigue and unexplained weakness are observed.
• Working capacity is deteriorating.
• Skin rashes appear.
• Avitaminosis. Its symptoms are reduced to increased fragility of nails, hair loss, peeling of the skin, etc.

The acute period lasts for five days, but sometimes it can last for a week. If a person has an immunodeficiency, then the acute period of giardiasis, as a rule, is longer, and all of the listed symptoms are manifested in full.

Sometimes in the acute phase, symptoms of biliary dyskinesia occur. If in children with giardiasis, the body temperature rises and symptoms of intoxication increase, then for adult patients such a clinical picture is not typical.

A week later, giardiasis either goes away on its own, or becomes chronic.

Symptoms of giardiasis in the chronic stage

Symptoms indicating a chronic form of giardiasis in adults:

• Disorders of the digestive system. The patient's stool becomes unstable, frequent constipation is replaced by the same frequent diarrhea. Appetite remains reduced, periodically disturbed by bloating and rumbling in the intestines.
• The general well-being of a person suffers. Headaches are often disturbed, excessive sleepiness and irritability appear. This condition leads to a deterioration in working capacity.
• Skin color deteriorates, and mild jaundice may develop. First of all, the neck, face, axillary folds, and abdomen acquire an icteric tint.
• Skin rashes begin to bother the patient more and more often, even if the person did not suffer from allergies before. The phenomena of dermatitis or urticaria are possible. Quincke's edema in adulthood against the background of giardiasis occurs extremely rarely, asthmatic bronchitis or bronchial asthma develops more often. The main features of allergies against the background of giardiasis are: long course, lack of response to antihistamines, frequent relapses.
• Especially difficult against the background of giardiasis in adults is urticaria, disrupting the patient's quality of life. Moreover, it occurs without any background errors in nutrition, without taking medications, etc. Very often, urticaria is accompanied by blepharitis.
• For chronic giardiasis, follicular keratosis is characteristic with the appearance of punctate swellings on the skin. The skin of the shoulders is mainly affected. It is covered with a rough crust or white rounded plaques, prone to increased desquamation.
• Xerosis is associated with giardiasis, in which the patient's heels flake off, especially in the cold season.
• Perhaps isolated lesion of the palms and feet, when the skin begins to peel off the tips of the phalanges. Fingers resemble senile fingers. As a rule, this process does not reach the palms.
• The mucous membrane of the oral cavity suffers. A person often has aphthous stomatitis, seizures appear in the corners of the mouth, the border of the lips becomes inflamed.
• Hair becomes thinner, becomes brittle, and loses its natural shine.
• The patient continues to lose body weight.

If lamblia in an adult is parasitized for a long time, then there will be signs of suppression of immunity and symptoms of intoxication. At the same time, the lymph nodes periodically become inflamed, the tonsils increase, the body temperature rises to subfebrile levels.

Another indirect sign of giardiasis in adults is intolerance to whole cow's milk, since these parasites infect enterocytes responsible for the hydrolysis of carbohydrate components of food. This also explains the increased gas production in the intestines.

Consequences of giardiasis

The consequences of giardiasis occur with a long course of the disease. First of all, the human immune system suffers, which provokes constant viral and bacterial diseases.

Secondly, the risks of developing chronic diseases of the digestive system increase, from which it will be impossible to get rid of even after the cure of giardiasis. Possible development of acute pancreatitis, cholecystitis, gastroduodenitis, ulcerative lesions of the stomach and intestines.

Thirdly, with parasitic invasion, the patient suffers from allergic reactions that can result in bronchial asthma. Its symptoms can also persist throughout life, even if giardiasis is cured.

Diagnostics

Diagnosis of lamblia in adults should be carried out without fail according to the following indications:

• Diarrhea that is persistent and not viral, autoimmune, or bacterial.
• Allergic and allergic-like diseases of the respiratory tract (bronchial asthma, obstructive bronchitis) and skin (urticaria, eczema, dermatitis, etc.).
• Increased blood eosinophils.
• Prolonged increase in body temperature to subfebrile levels.
• The presence of confirmed contact with an infected person.

Visual markers of patients with giardiasis are: dry skin, soreness of the mesogastrium, bloating, coated tongue, possibly an increase in liver size.

Modern diagnostics of lamblia in adults includes the following set of possible measures:

• Microscopic examination of feces.
• Feces PCR.
• Feces ELISA using rapid tests.
• PCR of the duodenal contents of the duodenum.
• ELISA blood test for giardiasis.

The basic diagnostic method is microscopic examination of feces. It must be carried out at least 3 times, especially if there is a suspicion of the presence of parasites in the human body. Most often, lamblia cysts are found in feces.

For the result to be as reliable as possible, the following conditions must be met:

• On the eve of the test, it is advisable to refuse to take rough food, mushrooms and liver, so as not to complicate the visualization of parasites;
• Do not use an enema to collect biomaterial;
• Refuse to take sorbents and antibiotics, or wait 2 weeks after the last dose of the drug;
• Feces are collected in a sterile container;
• The feces must be fresh, it must be delivered to the laboratory within an hour.

Additional methods for diagnosing giardiasis in adults can be such studies as: general blood and urine analysis, blood biochemistry, coprogram and seeding of feces for microflora, a test for lactase deficiency, EGDS, etc.

Treatment of giardiasis in adults

Treatment of lamblia in adults is carried out by an infectious disease doctor.

Before deciding on a therapy, the doctor must take into account such aspects as:

• The severity of the symptoms of the disease;
• The duration of the presence of lamblia in the intestine;
• The presence of concomitant diseases.

It is equally important to try to determine the source of the invasion in order to prevent reinfection. You should not start treatment with antiprotozoal drugs, as this will aggravate the symptoms of the disease and may provoke a reactive response of the body.

Therefore, the treatment of lamblia in adults is carried out in stages:

1. The preparatory stage before the treatment of giardiasis. At the preparatory stage, it is necessary to try to mechanically remove the maximum amount of lamblia from the intestine, as well as remove intoxication from the body. At this time, the patient must adhere to a dietary diet.

   To do this, the patient must observe the following recommendations:

   • Completely exclude sweets and carbohydrates from the menu, which are quickly absorbed;
   • Eat foods rich in fiber;
   • Eat protein foods;
   • Give up whole milk, limit the intake of fat;
   • Eat according to the regimen, switch to fractional meals (5-6 times a day);
   • Drink more liquid, preferring sour fruit drinks and choleretic broths.

   An addition to the diet is the intake of enterosorbents, choleretic drugs, antihistamines and digestive enzymes. Thus, conditions will be created in the intestine that are unfavorable for the reproduction of parasites and the rate of their division will significantly decrease.

2. The use of antiparasitic agents against lamblia. The second stage of antiparasitic therapy takes 5-10 days. All drugs are prescribed by the attending physician, since almost all drugs have contraindications and side effects.

   How to treat giardia in adults - list of medicines:

   

   • Metronidazole (Trichopol) - the dosage in adults is 0.4 g three times a day, vomiting, nausea, headache, sleep disturbances are possible.
   • Albendazole - 0.4 g once for 5 days, possibly the development of liver failure, nausea and vomiting, hyperthermia.
   • Fazizhin - one tablet 4 times a day for 2 days.
   • Macmiror - 15 mg per kg of body weight, taken twice a day after meals for a week, manifestations of diarrhea, gastralgia, skin rash, nausea and bitterness in the mouth are possible.
   • Furazolidone - rarely used, since the drug is ineffective against modern strains of parasites.

   The drugs and dosage for the treatment of children are selected with great care, trying to minimize the toxic effect of drugs.

   How to treat lamblia in children - medicines:

   • Flamin - 1/3 or 1/2 tablet three times a day, the course of treatment is designed for 10 days.
   • Macmiror - used from 2 years old at 15 mg per kg of body weight of a child, no more than 0.4 g in total. The course of treatment with a 2-fold intake takes 7 to 10 days.
   • Intetrix - recommended for children from one year old, the therapeutic dose is? -1-1? capsules three times a day.

   Simultaneously with taking antiparasitic drugs, both adults and children take a course of antihistamines, enzymes and sorbents.

3. Recovery of the body after treatment of giardiasis. The final stage of treatment is aimed at increasing the patient's immunity, at normalizing the intestinal microflora. To do this, he is prescribed vitamin and mineral complexes, intestinal bacteria, enzyme preparations.

As a rule, the prognosis for giardiasis in adults is quite favorable. In the event that the patient strictly follows all the prescriptions of the attending doctor, recovery is observed in 92-95% of cases. However, reinfection is not excluded, so the patient should remain on dispensary observation for another 3-6 months. During this time, it must be examined at least 2 times.

Treatment regimens for giardiasis

Treatment regimens for giardiasis are implemented using antiparasitic drugs, including:

• Tinidazole (Tinogin, Ametin, Fazizhin). It will take 1-2 days to take the selected drug. The treatment efficiency reaches 80%.
• Tiberal (Ornidazole). The drug can be taken in different ways: one day, three days, five days and ten days. The effect even with a one-day intake reaches 92%.
• Macmiror preparation "Poli industria chimica". The effectiveness of this drug reaches 96.8% after a week of administration.

After the end of treatment, you will need to conduct a control study for giardiasis. Once again, the parasitological examination is carried out after 30 days.

Prevention of lamblia in adults

Prevention of lamblia in adults is reduced to compliance with the following measures:

• Timely detection of cases of invasion, followed by high-quality treatment of patients with giardiasis.
• Following strict hygiene practices with regular hand washing.
• Use of boiled or bottled water for drinking.
• Preventing the ingress of fecal matter into the environment.
• Compliance with sanitary and hygienic measures in food and water supply establishments.
• Regular examination of people at risk for giardiasis.
• Conducting sanitary and educational work among the population by local authorities.

There is no vaccine against giardiasis, and the immunity that is developed after the illness is very unstable. Therefore, the risk of reinfection remains high.

Which doctor treats giardiasis?

An infectious disease doctor is engaged in the treatment of giardiasis.

Author of the article: Danilova Tatyana Vyacheslavovna | Infectionist

Education: in 2008 received a diploma in General Medicine (General Medicine) at the Pirogov Russian Research Medical University. Immediately passed an internship and received a diploma of a therapist