Diphyllobothriasis / Fish tapeworm infection

Infectious diseases

Clinicals - History

Fact Explanation
Abdominal pain Diphyllobothriasis is an infection of the cestode called Diphyllobothrium latum or Diphyllobothrium nihonkaiense. This disease is more common in Europe, North Asia, North America and South America. Diphyllobothriasis (Fish tape worm infestation) is a potential zoonosis. Human is the main host and is infected by eating raw, infected fish. Other fish eating mammals may also be infected.
Patients are usually asymptomatic. Symptoms of Diphyllobothrium are related to the worm burden. Abdominal pain may attributed to the trauma to the intestinal wall caused by adult worm. Rarely, patients may develop intestinal obstruction with severe mechanical
occlusion of the lumen. In such cases severe abdominal pain in the
peri umbilical area with nausea, vomiting or constipation may occur.
Abdominal pain
Diphyllobothriasis is an infection of the cestode called Diphyllobothrium latum or Diphyllobothrium nihonkaiense. This disease is more common in Europe, North Asia, North America and South America. Diphyllobothriasis (Fish tape worm infestation) is a potential zoonosis. Human is the main host and is infected by eating raw, infected fish. Other fish eating mammals may also be infected.
Patients are usually asymptomatic. Symptoms of Diphyllobothrium are related to the worm burden. Abdominal pain may attributed to the trauma to the intestinal wall caused by adult worm. Rarely, patients may develop intestinal obstruction with severe mechanical
occlusion of the lumen. In such cases severe abdominal pain in the
peri umbilical area with nausea, vomiting or constipation may occur.
Diarrhea Diarrhea is a very rare presentation of fish tapeworm infestation. When occurs it is insidious and watery in type. Diarrhea may be accompanied with nausea, vomiting and loss of appetite. Diarrhea
Diarrhea is a very rare presentation of fish tapeworm infestation. When occurs it is insidious and watery in type. Diarrhea may be accompanied with nausea, vomiting and loss of appetite.
Restlessness at night Passage of proglottids to the peri anal region causes restlessness and prutitus ani at night. Restlessness at night
Passage of proglottids to the peri anal region causes restlessness and prutitus ani at night.
Indigestion/ dyspeptic symptoms The characteristic symptoms of dyspepsia are upper abdominal pain, bloating, fullness and tenderness on palpation. Indigestion/ dyspeptic symptoms
The characteristic symptoms of dyspepsia are upper abdominal pain, bloating, fullness and tenderness on palpation.
Anaemic features Vitamin B12 deficiency with subsequent megaloblastic anemia may occur. This is thought to be due to utilization of vitamin B12 and/or folic acid by the parasites in the intestine or blood. Anemic patients can present with symptoms depending on severity including breathlessness, and neurologic symptoms such as numbness, weakness, and disturbances in coordination.. Anaemic features
Vitamin B12 deficiency with subsequent megaloblastic anemia may occur. This is thought to be due to utilization of vitamin B12 and/or folic acid by the parasites in the intestine or blood. Anemic patients can present with symptoms depending on severity including breathlessness, and neurologic symptoms such as numbness, weakness, and disturbances in coordination..

Clinicals - Examination

Fact Explanation
Stool examination Direct examination of the stools may help to observe white motile segments of Proglottids of Dipylidium caninum. Examination of the peri anal area may also useful as segments can be found as they crawl out of the anus. These are important findings in terms of diagnosis. Stool examination
Direct examination of the stools may help to observe white motile segments of Proglottids of Dipylidium caninum. Examination of the peri anal area may also useful as segments can be found as they crawl out of the anus. These are important findings in terms of diagnosis.
Abdominal tenderness This may or may not be demonstrated in the epigastric region and is due to local allergic reaction of the intestine and rarely may be attributed to intestinal obstruction, in which case tenderness will be accompanied with abdominal distention. Abdominal tenderness
This may or may not be demonstrated in the epigastric region and is due to local allergic reaction of the intestine and rarely may be attributed to intestinal obstruction, in which case tenderness will be accompanied with abdominal distention.
Neurological signs Vitamin B12 deficiency can lead to neurologic dysfunction. Patients may show a wide range of neurological manifestations ranging from numbness to the fingers and toes, difficulty walking, mood changes, depression, memory loss, disorientation and,
in severe cases, dementia.
Neurological signs
Vitamin B12 deficiency can lead to neurologic dysfunction. Patients may show a wide range of neurological manifestations ranging from numbness to the fingers and toes, difficulty walking, mood changes, depression, memory loss, disorientation and,
in severe cases, dementia.
Anemic features Pallor, glossitis, dyspnea and tachycardia are common in patients complicated with megaloblastic anemia. Anemic features
Pallor, glossitis, dyspnea and tachycardia are common in patients complicated with megaloblastic anemia.

Investigations - Diagnosis

Fact Explanation
Full blood count Parasitic infestation is characterized by high degree of eosinophilia.
Hemoglobin level and hematocrit low or at the lower end with Mean cell volume above or at the higher end of the reference ranges is indicative of macrocytic anemia.
Full blood count
Parasitic infestation is characterized by high degree of eosinophilia.
Hemoglobin level and hematocrit low or at the lower end with Mean cell volume above or at the higher end of the reference ranges is indicative of macrocytic anemia.
Stool examination for ova Identification of the operculated eggs in the stool is not difficult, as large quantity of eggs (≥1 million) produced each day. These eggs are oval or ellipsoidal, with at one end an operculum that can be inconspicuous. At the opposite (abopercular) end is a small knob that can be barely discernible. The eggs are passed in the stool unembryonated. Stool examination for ova
Identification of the operculated eggs in the stool is not difficult, as large quantity of eggs (≥1 million) produced each day. These eggs are oval or ellipsoidal, with at one end an operculum that can be inconspicuous. At the opposite (abopercular) end is a small knob that can be barely discernible. The eggs are passed in the stool unembryonated.
Vitamin B12 and/ or Folate level Some strains absorb vitamin B12 leading to Vitamin B12 deficiency and megaloblastic anemia in the human host. Vitamin B12 and/ or Folate level
Some strains absorb vitamin B12 leading to Vitamin B12 deficiency and megaloblastic anemia in the human host.

Management - Supportive

Fact Explanation
Prevention Prevention from consumption of raw fish specially when travel to endemic areas is the single best preventive method. Cooking fish to a temperature of 56 Celsius or more for more than 5 minutes or freezing to minus 18 Celsius for 24 hours will kills the plerocercoid larvae. Pickling fish in brine under very rigorous conditions will also kill the larva. The fish must be properly prepared before it is sampled . Prevention
Prevention from consumption of raw fish specially when travel to endemic areas is the single best preventive method. Cooking fish to a temperature of 56 Celsius or more for more than 5 minutes or freezing to minus 18 Celsius for 24 hours will kills the plerocercoid larvae. Pickling fish in brine under very rigorous conditions will also kill the larva. The fish must be properly prepared before it is sampled .

Management - Specific

Fact Explanation
Praziquantel Praziquantel is the drug of choice for Diphyllobothriasis. Single dose of 10-20 mg/kg after a light breakfast is recommended. 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 is the drug of choice for Diphyllobothriasis. Single dose of 10-20 mg/kg after a light breakfast is recommended. 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.
Niclosamide Niclosamide should be chewed thoroughly and be taken with water. 2g for adults as a single dose after a light breakfast is recommended. Dosage for children up to 2 years is 500mg and 1g for those between 3 to 6 years. This is an alternative to Praziquantel. Niclosamide
Niclosamide should be chewed thoroughly and be taken with water. 2g for adults as a single dose after a light breakfast is recommended. Dosage for children up to 2 years is 500mg and 1g for those between 3 to 6 years. This is an alternative to Praziquantel.
Vitamin supplementation Vitamin B12 and/or folic acid may be required in severe cases. Vitamin supplementation
Vitamin B12 and/or folic acid may be required in severe cases.

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