What is Fasciolopsidosis?
Fasciolopsidosis is a helminthiasis from the trematodoses group, which is characterized by mechanical tissue damage, intoxication with parasite metabolites, and a primary lesion of the gastrointestinal tract.
Fasciolopsidosis is registered in China, India, in the countries of Southeast Asia.
Causes of Fasciolopsidosis
The causative agent of fasciolopsis is trematode Fasciolopsis buski. Adults are lingual in shape, 15–50 mm long and 8.5–20 mm wide, of red-orange color. Eggs 0.13-0.14 ´ 0.08-0.095 mm, oval with a clearly visible lid.
The life cycle of fasciolopsidosis includes a change of three hosts. The final owners are man, cats, dogs, pigs; infected individuals secrete parasite eggs with feces. To begin the development cycle, they should get into a freshwater body of water, where in 2-3 weeks ciliated larvae, miracidia, emerge from them. Miracidia are introduced into the mollusks of the genus Planorbis (intermediate hosts), where their complex asexual reproduction occurs with the formation of caudate larvae (cercariae). Floating in water, the latter attach to aquatic vegetation (additional hosts) and turn into adolescaria (invasive forms). The entire development cycle of the parasite in water takes 90–95 days, adolescaria remain on plants and in moist soil for up to 2 years (they quickly die when they dry out). The final owners become infected by eating aquatic vegetation, especially watermelon nuts (Trapa natans), which people often clean with their teeth, or when drinking water from stagnant bodies of water. Swallowed larvae penetrate into the intestine, where they grow into adult parasites, sometimes helminths penetrate the liver and pancreas.
Pathogenesis during Fasciolopsidosis
A person becomes infected by eating aquatic plants infected with a pathogen (water chestnut, water chestnut, lotus, water).
The natural susceptibility of people is not defined.
Symptoms of Fasciolopsidosis
The incubation period lasts from several weeks to 2 months.
Clinical signs: chronic disorders of the digestive system (abdominal pain, flatulence, diarrhea), debilitating patients. With intensive invasion, swelling of the face, legs, scrotum, anemia is observed.
In the acute stage, there are acute abdominal pains and fetid diarrhea up to 5-6 times a day. In the chronic stage: moderate abdominal pain and intermittent stool disorder or severe intestinal crises, persistent diarrhea without blood, leading to cachexia; may occur in an edematous form with ascites or in a dry form with hypothermia, hypotension, extreme hypoproteinemia and anemia, which can lead to the death of the patient.
Diagnosis of Fasciolopsidosis
It is very difficult to make a diagnosis based on the clinical symptoms, since they are non-specific. The disease is diagnosed mainly on the basis of a coproovoscopic examination, in which F. buski eggs with their characteristic shape and large size are easily determined. Usually used native smear, if necessary, the method of deposition.
Prior to Duong Thai, a diagnostic antigen for an intracutaneous test, made of sexually mature F. buski, was tested in a pseudo-negative reaction. This method gives good results and can be used to diagnose those cases of F. buski invasion, when the parasites have not yet reached puberty and the eggs are not yet released along with the feces into the external environment. However, there is a cross-reaction to other trematodes: both to fascioli and paragonimus. Dang Van Ngy, Do Chan Than, Do Duong Thai showed that F. buski has antigens that are common with other trematodes.
Treatment of Fasciolopsidosis
Anti-helminth drugs (for example, praziquantel) are used to treat fasciolopsidosis and remove trematodes from the body.
With timely treatment, the prognosis is favorable.
Prevention of Fasciolopsidosis
Prevention of fasciolopsidosis consists in carrying out mass deworming of patients in endemic foci, protecting water bodies from contamination with feces. Water from open reservoirs used for drinking and household needs should be boiled. Tubers and fruits of aquatic plants, eaten, are subject to heat treatment.