Ceviche
About two years ago I had a patient who had a period of nausea and vomiting and then developed at chronic lump on her skin. On biopsy it was some sort of parasite. It was too degenerated to say for sure what it was.
Today I saw a patient in clinic who has had intermittent nausea and vomiting, with a 30 lb. weight loss, and an completely negative gi work up.
By history she has the same exposure as the patient of two years ago. Both ate a lot of ceviche, a citrus marinated raw fish, while in Mexico. How can that make you sick?
The raw fish carries a parasite, Gnathostoma spinigerum, that is not killed by the lemon juice, which causes Gnathostomiasis. Which just sounds unpleasant.
G. spinigerum used to be is SE asia, but it may have come to Mexico as part of the Tilapia fish farming.
“The life cycle of this parasite is as follows: Adult parasites of G. spinigerum are found in the stomach of mammals (e.g., dogs and cats), feces containing ova. Ova reach the water (i.e., when domestic parasitized animals live at the shore of a lagoon). Free-swimming first-stage larvae are formed, which are ingested by the minute copepod copepod: see crustacean. Any of the 10,000 known species of crustaceans in the subclass Copepoda. Copepods are widely distributed and ecologicaly important. Most of the 44,000 crustacean species are marine, but there are many freshwater forms. cyclops, and become second-stage larvae. Freshwater fish eating cyclops are the second intermediate host. Larvae develop to the third state (L3) in the fish muscles. Consumption of this fish by cats, dogs, or other mammals results in development of adults in the gut, closing the cycle. Humans acquire the infection by consuming raw or undercooked freshwater fish. When a larva is ingested by a human host, no further development occurs, but the larva migrates through subcutaneous tissue and internal organs where it produces migratory swelling in the skin and other symptoms depending on the site or organ affected. In most cases, symptoms are not serious; however, if the parasite migrates to vital organs of the host, it can cause severe illness or even death”
It is noted to cause eosinophilic meningitis and migratory itchy skin rashes as the parasite wanders through your tissues looking for a place to live. It can cause gastrointestinal symptoms, which has been the patients primary complaint, although there are features of the presentation (lack of eosinophilia) that make me doubt the diagnosis and I have pursuing some other ideas.
But as the first reference states
“A diagnosis of gnathostomiasis should be considered for patients with a history of transient, migratory cutaneous or subcutaneous swellings, or nonspecific gastrointestinal symptoms for which a potential epidemiologic exposure is identified.”
The main point of this entry?
Ooooo icky poopy, a worm.
The only good fish is a fried fish.
The best thing of all? If I am right I will have aced the diagnosis that another local ID doc missed. My enormous ego needs constant feeding.
Mmmmmmmm. Right diagnosis.
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http://www.cdc.gov/ncidod/eid/vol9no6/02-0625.htm
Emerg Infect Dis. 1999 Mar-Apr;5(2):264-6. Gnathostomosis, an emerging foodborne zoonotic disease in Acapulco, Mexico. Between 1993 and 1997, 98 gnathostomosis cases were clinically identified in Acapulco, Mexico. Intermittent cutaneous migratory swellings were the commonest manifestation. Larvae were identified in 26 cases, while in 72, final diagnosis was made on the basis of epidemiologic data, food habits, and positive enzyme-linked immunosorbent assay and Western blot results.
Ugh. Well… at least we can still eat sourdough.