Worms Flashcards
Schistosomiasis: Acute disease
Cercarial dermatitis
Katayama fever = fevers, abdominal pain, eosinophilia
Schistosomiasis: Chronic disease
granulomatous colitis (S. mansoni)
portal hypertension (S. mansoni)
granulomatous cystitis (S. haematobium)
bladder fibrosis and cancer (S. haematobium)
CNS disease (eggs to brain/spinal cord, esp S. japonicum)
Katayama Fever
Acute Schistosomiasis
- fever, myalgias, abdominal pain, headache, diarrhea, urticaria
- Eosinophilia, ^AST, ^alkaline phosphatase
When to consider Schistosomiasis
- Fresh water exposure in an endemic region.
- Acute: Fever, abd pain, myalgias, eosinophilia
- Chronic: schistosomiasis (abdominal pain, blood in stool, loose stools, evidence of portal HTN, hematuria, eosinophilia)
Fasciola hepatica (a liver fluke)
Risk factors:
S&S:
Dx:
- acquired by eating encysted larvae on aquatic vegetation (e.g. water chestnuts)
- fluke migration through the liver: RUQ pain and hepatitis; can induce biliary obstruction
- Dx: eggs in stool exam (low sensitivity), serology
Clonorchis sinensis “Chinese Liver Fluke”
Opisthorchis viverrini Southeast Asian Liver Fluke”
Chronic complications
- biliary obstruction
- cholelithiasis
- cholangiocarcinoma
HTLV-1 infection
(worms)
⇔
Strongiloides sterocoralis
Taenia solium ⇔
Taenia saginatum ⇔
Diphyllobothrium latum ⇔
Taenia solium ⇔ pork, Neurocysitcercosis
Taenia saginatum ⇔ beef
Diphyllobothrium latum ⇔ B12 deficiency
Paragonimus westermani “lung fluke”
freshwater crabs and crayfish; undercooked seafood
Adults migrate to LUNGS, frequent EOSINOPHILIA
- fever, cough, diarrhea during acute migration
- later, may have chest pain as worms migrate through lungs
- can develop chronic pulmonary symptoms
Dx: Sputum and/or stool exam for eggs.
Echinococcus granulosus - Most cysts (65%) in the liver 25% in the lung
Common presentations
- allergic symptoms/anaphylaxis due to cyst rupture after trauma
- cholangitis and biliary obstruction due to rupture into biliary tree
- peritonitis b/c intraperitoneal rupture
- pneumonia symptoms due to rupture into the bronchial tree
Typically treat with albendazole for several days before surgery or PAIR (usually 2d-1wk before, and 1-3 months after)
Enterobius vermicularis (pinworm)
- Humans are the only hosts
- peri-anal itching in some pts Dx: “scotch tape test” or swube, eggs with one flat side
Rx: albendazole, mebendazole, or pyrantel pamoate single dose repeat in 2 wks b/c risk reinfection.
treat all members of households
Body location of filarial infections
Wuchereria bancrofti / Brugia malayi (lymphatic filariasis) –mosquitoes–
- lymphatics
Loa loa (eyeworm) –Chrysops flies–
- SQ tissues (moving)
Onchocerciasis (river blindness) –blackflies–
- SQ tissues (nodules)
Onchocerca lupi -> an infection of wolves
as with O. volvulus, is transmitted by blackflies - 6 human cases reported to date - 3 with deep nodules near cervical spinal cord - Southwestern U.S.(Arizona, New Mexico, Texas)
Trichinellosis
Eat meat containing cysts (pork, boar, horse, wild game)
ABDOMINAL CRAMPS and DIARRHEA IF HEAVY INFXN
Larvae migrate to striated muscle, causing:
- SEVERE MUSCLE PAIN
- PERIORBITAL EDEMA
- EOSINOPHILIA +/- fever and urticaria
Angiostrongylus cantonensis (the rat lungworm)
- Primarily found in SE Asia, Pacific basin, Caribbean (Jamaica)
- Caused by ingestion of parasites in snail or slugs (often on vegetables) OR ingestion of paratenic hosts (prawns, shrimps, crabs)
- In humans, develop to young adults and cause meningitis 1-2 weeks after infection
Anisakis
> undercooked seafood/sushi (found worldwide);
> parasite buries its head into gastric mucosa.
Symptoms 1) due to invasion of worm (pain, vomiting) 2) due to allergic rxn to worm (mild urticaria, itchy sensation back of throat, anaphylactic shock)
