Metagonimiasis - Clinicals, Diagnosis, and Management

Infectious diseases

Clinicals - History

Fact Explanation
Diarrhea Metagonimiasis is a disease caused by an intestinal trematode known as Metagonimus yokagawai. The human becomes infected by ingesting undercooked or salted fish containing metacercariae. The metacercariae excyst, attachs to the mucosa of the small intestine after ingestion which then mature into adults. As they get attached to the intestinal mucosa, local inflammatory reactions take place. Most patients do not show any symptoms. Appearance of symptoms depends on the parasitic load. Watery type of mild diarrhea appears insidiously and is accompanied with nausea, vomiting and anorexia rarely. When present in large numbers, can cause chronic intermittent diarrhea. Diarrhea
Metagonimiasis is a disease caused by an intestinal trematode known as Metagonimus yokagawai. The human becomes infected by ingesting undercooked or salted fish containing metacercariae. The metacercariae excyst, attachs to the mucosa of the small intestine after ingestion which then mature into adults. As they get attached to the intestinal mucosa, local inflammatory reactions take place. Most patients do not show any symptoms. Appearance of symptoms depends on the parasitic load. Watery type of mild diarrhea appears insidiously and is accompanied with nausea, vomiting and anorexia rarely. When present in large numbers, can cause chronic intermittent diarrhea.
Abdominal pain Localized allergic reaction results in colicky type of intermittent abdominal pain. Heavy infection has also been associated with epigastric distress, fatigue, and malaise. Abdominal pain
Localized allergic reaction results in colicky type of intermittent abdominal pain. Heavy infection has also been associated with epigastric distress, fatigue, and malaise.
Neurological manifestations Occasionally, flukes invade the mucosa and eggs deposited in tissue may gain access to circulation. This can then lead to eggs embolizing in the brain causing seizures and other neurological deficits. Neurological manifestations
Occasionally, flukes invade the mucosa and eggs deposited in tissue may gain access to circulation. This can then lead to eggs embolizing in the brain causing seizures and other neurological deficits.
Chest pain Rarely, when the eggs of the flukes move into the heart, fatal valvular and myocardial damage may occur. The resultant arrhythmias may manifest as a chest pain. Chest pain
Rarely, when the eggs of the flukes move into the heart, fatal valvular and myocardial damage may occur. The resultant arrhythmias may manifest as a chest pain.
At risk population Metagonimiasis mostly occurs in the Far East, as well as Siberia, Manchuria, the Balkan states, Israel, and Spain. Ingestion of undercooked, salted, pickled, or smoked freshwater fish poses a greater risk. Incidences are higher in fishermen, fishmongers, workers in processing fish products, officials than in those with other occupations. At risk population
Metagonimiasis mostly occurs in the Far East, as well as Siberia, Manchuria, the Balkan states, Israel, and Spain. Ingestion of undercooked, salted, pickled, or smoked freshwater fish poses a greater risk. Incidences are higher in fishermen, fishmongers, workers in processing fish products, officials than in those with other occupations.

Clinicals - Examination

Fact Explanation
Abdominal tenderness Mild abdominal tenderness is possible due to the inflammation of the bowel mucosa. Abdominal tenderness
Mild abdominal tenderness is possible due to the inflammation of the bowel mucosa.
Cardiac murmers Very rarely cardiac murmurs may be auscultated owing to the myocarditis and eventual heart failure. Cardiac murmers
Very rarely cardiac murmurs may be auscultated owing to the myocarditis and eventual heart failure.
Neurological signs In rare instances, neurological signs such as paresis can be found, depending on the extent that the cerebral emboli is affected. Neurological signs
In rare instances, neurological signs such as paresis can be found, depending on the extent that the cerebral emboli is affected.

Investigations - Diagnosis

Fact Explanation
Full blood count Parasitic infestation is characterized by high degree of eosinophilia. Leukocytosis and anemia (rarely) may also occur. Full blood count
Parasitic infestation is characterized by high degree of eosinophilia. Leukocytosis and anemia (rarely) may also occur.
Stool examination The diagnosis depends on the demonstration of eggs in stool specimens. Concentration techniques and repeated examinations will increase the likelihood of detecting light infections. However, the eggs are indistinguishable from those of Heterophyes and resemble those of Clonorchis and Opisthorchis. The eggs from Heterophyes are small, oval and brown, with embryo and operculum / lid. They are 28 to 30 microns long and 15 to 17 microns wide. Specific diagnosis is based on identification of the adult fluke evacuated after antihelminthic therapy, or found at autopsy. Stool examination
The diagnosis depends on the demonstration of eggs in stool specimens. Concentration techniques and repeated examinations will increase the likelihood of detecting light infections. However, the eggs are indistinguishable from those of Heterophyes and resemble those of Clonorchis and Opisthorchis. The eggs from Heterophyes are small, oval and brown, with embryo and operculum / lid. They are 28 to 30 microns long and 15 to 17 microns wide. Specific diagnosis is based on identification of the adult fluke evacuated after antihelminthic therapy, or found at autopsy.

Management - Supportive

Fact Explanation
Prevention Avoidance from having raw, undercooked or pickled wish is the best preventive method. Using molluscicides for snail (a host) control have been successful. Prevention
Avoidance from having raw, undercooked or pickled wish is the best preventive method. Using molluscicides for snail (a host) control have been successful.

Management - Specific

Fact Explanation
Praziquantel Praziquantel as a single dose (25 mg/kg or less) is the current treatment of choice. Frequently occurring side effects are dizziness, headache, and malaise. Approximately 90% of all patients have abdominal pain or cramps with or without nausea and vomiting. Praziquantel
Praziquantel as a single dose (25 mg/kg or less) is the current treatment of choice. Frequently occurring side effects are dizziness, headache, and malaise. Approximately 90% of all patients have abdominal pain or cramps with or without nausea and vomiting.

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