A Case of Angiostrongylus cantonensis Infection Involving the Liver in Shaoxing.

Background: Angiostrongylus cantonensis is a rare zoonotic parasitic illness contracted by consuming raw or semi-raw food contaminated with the third-stage larvae of Angiostrongylus cantonensis, such as freshwater shrimps, fish, snails, frogs, etc. [1]. The parasite can stimulate the host to generate an immune response and cause tissue damage, primarily invading the central nervous system of the human body. However, the liver is relatively infrequently affected and is prone to missed diagnosis and misdiagnosis.

Methods: Comprehensive laboratory routine examinations, including blood routine, biochemistry, and others, were carried out on the patient. Additionally, abdominal enhanced CT and MRI imaging inspections were conducted, and in combination with the patient's epidemiological history, parasitic antibodies, and mNGS were detected.

Results: Blood routine examination reveals a white blood cell count of 12.54 x 109/L, with an eosinophil percentage of 52.9%. The C-reactive protein (CRP) is 45.74 mg/L, alanine aminotransferase (ALT) is 325 U/L, aspartate ami-notransferase (AST) is 149.2 U/L, alkaline phosphatase (ALP) is 324.7 U/L, gamma-glutamyl transferase (r-GT) is 424.8 U/L, and lactate dehydrogenase (LDH) is 375 U/L. A full abdominal enhanced CT scan indicates multiple low-intensity foci in the liver. An enhanced MRI of the upper abdomen shows abnormal liver signals, suggesting a higher possibility of inflammatory lesions. The parasite antibody test turned out positive for antibodies against Angiostrongylus cantonensis. It is considered that the patient is infected with Angiostrongylus cantonensis involving the liver. After two weeks of clinical treatment with albendazole, the patient's symptoms improved, and no significant abnormalities were detected in related examinations.

Conclusions: Shaoxing is a non-endemic region of Angiostrongylus cantonensis. The diagnosis and treatment of this disease are rather challenging, and cases involving liver are even rarer. During the process of diagnosis and treatment, if an abnormal increase of eosinophils is detected in routine blood tests, in combination with clinical symptoms and epidemiological history, tests such as parasitic antibodies and mNGS should be added for a clear diagnosis.