Novel mechanism of hepatobiliary system damage and immunoglobulin G4 elevation caused by Clonorchis sinensis infection

Abstract

Clonorchis sinensis infection is still a major public health problem. It is estimated that more than 15 million people worldwide are infected, especially in Northeast China, Taiwan, South Korea, and North Vietnam. The detection of Clonorchis sinensis eggs in feces and bile is still the only gold standard for the diagnosis of Clonorchis sinensis infection, and new detection methods are needed to improve the detection rate. After Clonorchis sinensis invades the human body, it mainly parasitizes the hepatobiliary tract. Therefore, it is closely related to hepatobiliary diseases such as cholangitis, bile duct stones, liver fibrosis, and cholangiocarcinoma. The increase in immunoglobulin G4 (IgG4) caused by Clonorchis sinensis infection is rare and there are few reports about the relevant mechanism. It may be related to the inflammatory factors interleukin (IL)-4, IL-10, and IL-13 produced by human phagocytes, T cells, B cells, and other immune cells in the process of resisting the invasion of Clonorchis sinensis . However, this finding still needs further clarification and confirmation. This article reviews the epidemiology, clinical manifestations, serology, imaging, pathogenic mechanism, and control measures of Clonorchis sinensis infection to help establish the diagnostic process for Clonorchis sinensis . We report novel mechanisms of IgG4 elevation due to Clonorchis sinensis infection to provide more experience and a theoretical basis for clinical diagnosis and treatment of this infection.

Clonorchis sinensis infection in a non‑endemic area: A case report

“…Subsequent to infection, the main clinical manifestations encompass cholangitis, cholecystitis and gallbladder stones and complications, such as biliary obstruction, abscesses and even cholangiocarcinoma (12). A predominant laboratory finding associated with Clonorchis sinensis infection is an elevated eosinophil count or percentage (13). In the present case, the preoperative blood tests indicated an eosinophil percentage of 16% and an absolute eosinophil count of 0.9x10 9 /l.…”

“…In the present case, high signal was observed on T2WI, and diffuse mildly dilated terminal bile ducts were observed both in the center and periphery of the lesion. This characteristic is attributed to Clonorchis sinensis predominantly infesting the terminal bile ducts, causing obstructions in the smaller peripheral ducts (13). The most common finding on MRI of Clonorchis sinensis is a diffuse mild dilatation of the small intrahepatic bile ducts without dilatation of the extrahepatic bile ducts (15).…”