A case of hepatic anisakiasis caused by Pseudoterranova decipiens mimicking metastatic liver cancer

Abstract

BackgroundAnisakid nematodes (Anisakis spp. or Pseudoterranova spp.) usually infect gastric or intestinal walls, while they rarely infect in extra-gastrointestinal sites of human body. Generally, Anisakis spp. larvae are highly infected in fish intermediate hosts, whereas Pseudoterranova spp. larvae are very rarely infected. To the best of our knowledge, there have been no reports which have documented cases of hepatic anisakiasis caused by Pseudoterranova spp. This report describes the first documented case of hepatic anisakiasis due to infection with Pseudoterranova decipiens and clinical features of the hepatic anisakiasis through literature review.Case presentationThe case was a 28-year-old man with prior history of malignancy who was found to have a hepatic mass mimicking metastatic liver tumor. A new low density area of 20 mm in diameter in liver segment 7 was found on follow-up CT. With suspicious diagnosis of metastatic liver cancer, laparoscopic partial hepatectomy was performed. A pathological examination revealed no evidence of malignancy, but showed necrotic granuloma with eosinophil infiltration and the presence of a larva with Y-shaped lateral cords, which are specific to anisakid larvae. The type of larva was identified as Pseudoterranova decipiens sensu lato using PCR of DNA purified from a fixed granuloma embedded in paraffin.ConclusionThe present report is the first to discuss the case of a patient with hepatic anisakiasis caused by Pseudoterranova decipiens. Hepatic anisakiasis is a potential differential diagnosis for hepatic tumors and genetic identification with the PCR method was reliable for obtaining final diagnosis even when the larvae body in the resected specimen collapses with time.

Species of Anisakidae nematodes and Clinostomum spp. infecting lisa Mugil curema (Mugilidae) intended for human consumption in Mexico

“…Identification of a granuloma in hypaxial muscle, and the presence of the exogenous material inside, suggests that a parasite was encysted and that the immune system was involved in its destruction. The structural elements described in this work are consistent with those reported by Murata et al (2018) for a case of hepatic anisakiasis; however, in this work, elongated bacillary structures were observed in the center of the lesion, suggesting the presence of nematode-like bacteria, such as Flavobacterium spp., Pseudomonas spp., or Bacillus cereus (Svanevik & Lunestad, 2017). The histopathology of the nematode revealed the lateral epidermal cord in the form of a thick "T"; this is probably because the tissue was squashed and the structure changed; however, there is a possibility that the shape of the cord may be related to the parasitic genus, although more studies are needed to test this hypothesis.…”

“…and butterfly wing shape for Pseudoterranova spp. (Lauwers et al, 2017); the specification of this structure in human medicine has been reported for hepatic anisakiasis due to Pseudoterranova decipiens (Murata et al, 2018), A. pegreffii, and A. simplex in cases of dysentery (Amir et al, 2016). In fish, only Laffon-Leal et al (2000) reported the genus Contracaecum spp.…”

Advances in Omic Studies Drive Discoveries in the Biology of Anisakid Nematodes

“…Anisakids are responsible for a relatively poorly known food-borne zoonosis named anisakiasis or anisakidosis that results from the accidental ingestion of marine products harboring infective L3 in the edible parts. The pathology shows mild-to-severe gastrointestinal and/or allergic symptoms and clinical signs, such as rhinitis, urticaria, and anaphylactic shock [ 3 ], and there is increasing evidence that suggests the occurrence of tumors in the same localization of larvae [ 4 , 5 , 6 ]. For these reasons, the need to fill the gap in knowledge about the pathogenetic mechanisms of such parasitic disease appears clear.…”

Genera and Species of the Anisakidae Family and Their Geographical Distribution

“…The distribution of nematodes of the Anisakidae family is worldwide, and their identification through molecular tests has been carried out more frequently in the Asian continent [ 115 ], where the consumption of fish is higher, registering a per capita consumption of 24.1 kg/year [ 12 ], which is consistent with the Asian diet, which is based mainly on the consumption of raw and semi-raw seaFood In a study by Yokogawa and Yoshimura [ 116 ], they reported parasitic infestation by Anisakis spp. in Japanese patients with clinical symptoms affecting the gastrointestinal tract, using the term “larval anisakiasis” to determine that the disease was caused by a parasite of the Anisakidae family through the consumption of raw fish and squid.…”

“…Encystment has also been observed in the intestinal epithelium that can trigger the presentation of cancer; however, this will depend on the mutagenicity of the cells and the tumor-promoting potential of larval antigens [ 145 ]. In a study carried out by Murata et al [ 115 ], a case of hepatic anisakidosis caused by P . decipiens was reported, which was first diagnosed in the patient as a neoplasm; however, when analyzing the tumor, it was identified that it was an eosinophilic granuloma, in which the larva was located at the center of the lesion.…”