Anisakis spp. - macroscopic and microscopic exam; Molecular identification of species by sequencing.
Anisakidosis or anisakiasis, is a marine zoonosis caused by the larvae of several species of anisakidae (anisakid) The species found affecting people are: Anisakis simplex, pegreffii Anisakis, Pseudoterranova decipiens, Contracaecum osculatum and Hysterothylacium auctum / aduncum ). Other species are: Anisakis typica, Anisakis physeteri, Anisakis schupakovi, Anisakis ziphidarum, Pseudoterranova ceticola, Pseudoterranova krabbei. Adult worms parasitize the intestine of several species of marine mammals (definitive host), mainly cetaceans. With the feces of these marine mammals eggs that develop the first larval stage when hatches are ingested by some marine microscopic crustaceans are removed (p. Eg. Euphasia spp. And Trysanoessa spp.), Which second instar develops ( first intermediate) hosts. These crustaceans, in the marine food chain, are ingested by fish or cephalopods (squid, cuttlefish, octopus, ...) (second intermediate host) in the third larval stage which is encapsulated in various tissues mainly it develops mesentery and liver but also in muscles, as with Anisakis simplex. When these fish or cephalopods ingested by marine mammals, the fourth larval stage resulting in the corresponding adults in the gut develops, completing their life cycle.
People become infected when they eat raw fish or cephalopods, undercooked or marinades. In the affected anisakidosis (anisakiasis) ingested larvae migrate from the small intestinal lumen, penetrate the mucosa and submucosa, initially causing discomfort and / or abdominal pain. Subsequently give rise to eosinophilic granulomas with discomfort depending on their location migration, and allergic problems . In sensitized persons, the ingestion of antigens anisakid, but are not viable can cause allergic reactions by IgE - mediated hypersensitivity.
Detecting larval fish tissue or cephalopods, you can be performed by the following methods:
· Direct microscopic visualization of larvae.
· Microscopic larvae display pépsica after digestion.
· Molecular identification of species.
Tests in IVAMI:
Helminth obtained from a monkfish liver, received IVAMI alive and identified as Pseudoterranova decipiens larva.