Diphyllobothrium latum
Background
- A type of tapeworm infection
- D. latum and D. nihonkaiense are most common pathogens[1]
- 15-45 day latency period
- Found mostly in cold waters Palaearctic region and North America[1]
- Generally due to eating raw or undercooked fish.
- In US, Great Lakes and Alaska are most common locations.
Clinical Features
- Usually asymptomatic or mild GI symptoms[1]
- 20% of cases report diarrhea, abdominal pain or discomfort
- Rarely, migrating proglottids can cause cholangitis, cholecystitis, or intestinal obstruction
- Competes for absorption of vitamin B12 → can cause pernicious anemia
Differential Diagnosis
Helminth infections
Cestodes (Tapeworms)
- Taenia saginata
- Taenia solium (Cysticercosis)
- Diphyllobothrium latum
- Hymenolepis nana
- Echinococcus granulosus
Trematodes (Flukes)
- Fasciola hepatica
- Fasciolopsis buski
- Opistorchis viverrini
- Schistosoma spp
- Chlonorchis sinensis
- Paragonimus spp.
Nematodes (Roundworms)
- Ascaris lumbricoides
- Enterobius vermicularis (Pinworm)
- Filarial worms
- Hookworm
- Necator americanus
- Ancylostoma duodenale
- Cutaneous larva migrans (Ancylostoma braziliense)
- Dracunculiasis
- Strongyloides stercoralis
- Trichuris trichiura (Whipworm)
- Anisakis
- Toxocara spp.
- Trichinosis
Evaluation
- Stool sample - morphologic identification of eggs[1]
- Molecular (PCR) diagnosis also possible, but less used
Management
- Praziquantel 25mg/kg x1 dose[1] OR
- Niclosamide 2 grams x1 dose
- Replace vitamin B12 if patient has megaloblastic anemia
Disposition
- Discharge