The characteristic localization of the parasite in the body of the final host promotes the same localization in the human body. Therefore, there are some specific symptoms of fascioliasis, which are characteristic for the defeat of this group of flukes.
Upon entering the human intestine, giant fasciolae eggs develop and grow, then they enter the submucosal layer at the larval stage and are absorbed into the blood. With blood flow through the portal vein system, the parasite enters the liver where it is updated. There is a further growth of larvae, their activation - in this state they are able to move along the ducts and enter the gallbladder, during which the normal arrangement of the duct and their relationship is disturbed. The function of bile outflow is violated in the first place, and as a secondary process bile stagnation occurs and the function of the liver itself is disrupted.
The incubation period lasts from a few days to five to seven weeks. In this case, a person may not remember the fact of infection, which makes diagnosis very difficult. This period lasts from the moment of getting into the intestine before activation in the liver and the violation of its function.
The acute stage of the disease develops at a single-stage massive liver injury with a significant number of parasites. In this case, the symptoms are very pronounced. There is jaundice, which causes patients to consult a doctor. It is accompanied by the itching of the skin, since the release of bile acids into the blood is expressed. At the same time, there are symptoms of pain in the right side or right upper quadrant, the severity of the pain syndrome increases with the use of fatty foods. Pain can also be blunt, mild. Often an attendant symptom is an allergic rash. This symptom is often observed due to the ability of helminths to cause increased allergization of the body, which is more often manifested by a diffuse rash all over the body with itching of the skin. Also, with an acute course, dyspeptic phenomena can occur-bitter taste in the mouth, nausea, vomiting, abdominal pain, and stool discomfort by the type of diarrhea.
But such an expanded clinic is less common than latent flow. Often, with a small number of parasites, there are little expressed symptoms, maybe only asthenovegetative syndrome, which can not be explained. In this case, a chronic form is formed, which is characterized by a slow constant release of eggs into the lumen of the intestine, and then reinfection. With this, there can be no symptoms on the part of the liver, only changes in allergic reactivity and the formation of a predisposition to stone formation and chronic cholecystitis in the gallbladder are expressed.