Anisakidosis: Symptoms, Photos, Treatment

2024 Author: Rachel Wainwright | [email protected]. Last modified: 2023-12-15 07:39

Anisakidosis

The content of the article:

1. Causes and risk factors
2. Forms of the disease
3. Symptoms
4. Diagnostics
5. Treatment
6. Possible complications and consequences
7. Forecast
8. Prevention

Anisakidosis (a disease of cod or herring worms) is a parasitic disease caused by the ingestion of larvae of nematodes of the family Anisakidae into the human body. The first case was reported in 1955 in Holland; it was associated with eating poorly salted herring. Currently, this helminthiasis is recorded in almost all countries of the world.

Anisakid larvae have an elongated or spiral shape, reach 50 mm in length, 1–2 mm in diameter, light-colored or stained with blood. You can see them in infected fish meat with the naked eye. The main hosts of anisakids are marine mammals (seals, dolphins, walruses), intermediate hosts are crustaceans, squids, sea and anadromous fish. Man is a casual master; in his body, the larva dies without further development.

Anisakids is a parasitic disease caused by the larva of nematodes of the family Anisakidae

According to the research results, 15% of sprat, 28% of mackerel, 36% of hake, 34% of pollock, 21% of Baltic herring, 25% of cod, 40% of Atlantic herring are infected with anisakids.

Causes and risk factors

Human infection with anisakid larvae occurs as a result of eating poorly salted or not sufficiently heat-treated marine fish. Seafood (cephalopods, crustaceans) that have not been heat treated are also dangerous.

Once in the digestive tract, the larvae invade the mucous membrane of the stomach and small intestine. Invasion into the mucous membrane of the large intestine is also possible, but this is rarely observed. At the site of the lesion, granulomatous eosinophilic tumors develop, accompanied by edema and thickening of the intestinal or stomach wall. These tumors are often mistaken for regional enteritis or gastric carcinoma.

Anisakids are found in poorly salted and not properly processed fish

Forms of the disease

Depending on which organ is affected by the larvae, the intestinal and gastric forms of anisakidosis are secreted. Also known is the asymptomatic form - transient.

According to the clinical course, acute, subacute and chronic anisacidosis are distinguished.

Symptoms

The incubation period is 1-2 weeks. With the intestinal form of the disease, the clinical picture is scanty: abdominal pain and flatulence.

If the granulomatous tumor reaches a large size, it can disrupt the movement of intestinal contents, which causes the development of mechanical intestinal obstruction with corresponding symptoms. Helminth larvae in the process of vital activity can lead to perforation of the intestinal wall. In this case, the intestinal contents enter the abdominal cavity and cause the development of peritonitis, which is clinically manifested by the symptom complex of "acute abdomen".

More often there is a gastric form of anisacidosis, which is characterized by:

• nausea;
• vomiting mixed with blood;
• severe pain in the epigastrium;
• an increase in body temperature to febrile values.

Transient anisacidosis is a mild form of helminthiasis that is asymptomatic or with throat irritation and coughing, during which the larvae are removed from the body.

Nausea, vomiting, abdominal pain - frequent companions of anisacidosis

The waste products of anisakid larvae cause sensitization of the body, which is caused by allergic reactions, the most dangerous among which are Quincke's edema and anaphylactic shock. Allergies appear within 1-12 hours after ingestion of the contaminated food.

Diagnostics

Diagnosis of anisacidosis is based on the clinical manifestations of the disease, as well as history data (eating raw sea fish or seafood).

Anisakid larvae can be detected by microscopy of biopsy material, and in some cases - in the feces or vomit of the patient.

In a clinical blood test, eosinophilia and moderate leukocytosis are detected. Anisakidosis requires differential diagnosis with diseases of the gastrointestinal tract: colitis, enteritis, diverticulitis, appendicitis, cholecystitis, pancreatitis, gastritis, gastric ulcer and duodenal ulcer, tumors of the stomach and intestines.

Treatment

A specific therapy for anisacidosis has not been developed, therefore, the treatment is symptomatic: anti-nematodic drugs of a wide spectrum of action, antihistamines, anti-inflammatory drugs.

With the development of intestinal perforation or intestinal obstruction, patients are hospitalized in the surgical department for emergency surgery.

Possible complications and consequences

The most serious complications of anisacidosis are:

• intestinal obstruction;
• intestinal perforation;
• peritonitis;
• Quincke's edema, anaphylactic shock.

All of these complications are life threatening; if, during their development, the patient is not provided with emergency medical care, he may die.

Forecast

With timely treatment of anisacidosis, the prognosis is favorable. With the development of complications, it becomes heavier.

Prevention

In order to prevent anisacidosis, the following rules should be followed:

• do not eat raw or lightly salted sea fish;
• store fish and seafood at low temperatures, since helminth larvae die within 10 minutes at a temperature of -30 ^° C, and at -18 ^° C they retain their viability for 2 weeks;
• carry out heat treatment of fish - at a temperature of +60 ^° C, anisakid larvae die almost instantly;
• for cutting raw fish in the kitchen, a separate knife and cutting board should be used, which after finishing work should be thoroughly washed with soap and doused with boiling water.

The correct choice, storage and preparation of fish is the basis for the prevention of anisakidosis

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Elena Minkina Doctor anesthesiologist-resuscitator About the author

Education: graduated from the Tashkent State Medical Institute, specializing in general medicine in 1991. Repeatedly passed refresher courses.

Work experience: anesthesiologist-resuscitator of the city maternity complex, resuscitator of the hemodialysis department.

The information is generalized and provided for informational purposes only. At the first sign of illness, see your doctor. Self-medication is hazardous to health!