The effect of infection with Entamoeba histolytica on the level of some biological variables and histological changes in the liver

Background: Entamoeba histolytica is an intestinal protozoan parasite that causes “dysentery,” leading to Amebic colitis and a liver abscess. Infection begins with ingesting infective stages, represented by the cystic form found in contaminated food and drink; the parasite attacks the tissues by attaching to the epithelial lining of the intestine, and adhesion occurs through virulence factors. Objective: Detection of the E. histolytica parasite using the direct swab method, study the histological changes in the liver and some blood parameters of animals infected with E. histolytica and compare these with uninfected groups. Material and method: The current study was conducted between May 1, 2021, and October 30, 2022, to diagnose infection with E. histolytica. Samples were taken from clinically infected patients who suffered from diarrhea and examined microscopically using a direct wet swab. In the experimental study, E. histolytica was given to laboratory mice. Male laboratory mice were divided into four groups. The first group represented the negative control group, dosed with Normal saline only. Results: The negative control group showed normal liver histological sections. The hepatic lobule appeared to include hepatic cells, which were arranged radially, as they appeared as cords extending from the central vein, in addition to diagnosing normal liver cells. With central round nuclei and a homogeneous appearance of cytoplasm, hepatic lamellae, and hepatic sinusoids, the second group represented the positive control group. It was treated with the parasite E. histolytica, which recorded numerous histological changes in the livers of the group, which included irregular radiological appearance of the hepatic cells around the hepatic vein, infiltration of lymphocytes, and necrosis and swelling of some hepatic cells, there was an increase in liver enzymes, indicating infection with E. histolytica. Conclusion: Laboratory animals infected with E. histolytica had histological changes in the liver, represented by necrosis, nucleolytic, and amoebic liver abscesses. Although the parasite infects the intestines and settles there, it causes secondary infections through its transmission through the blood and lymph to the liver.