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Strongyloides Stercoralis. EPIDEMIOLOGY. • 100 millions people infected worldwide • All tropical and subtropical regions • Europe (Northern Italy, France, Spain, Switzerland, Poland) • USA (Appalachian region, West Virginia) • Japan (Okinawa) • Australia (aboriginal populations.
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Strongyloides Stercoralis para-lab byl.wafa menawi
EPIDEMIOLOGY • • 100 millions people infected worldwide • • All tropical and subtropical regions • • Europe (Northern Italy, France, Spain, • Switzerland, Poland) • • USA (Appalachian region, West Virginia) • • Japan (Okinawa) • • Australia (aboriginal populations para-lab byl.wafa menawi
Unique among the nematode parasites of humans in that it has a free-living life cycle and an auto infective cycle in addition to the normal parasitic type life cycle. Hosts: Natural: Humans other primates ,dogs,cats Experimentally: Gerbils,Patas monkeys,mice Reproduction: Parasitic adults are parthenogenesis. Free-living adults are sexual para-lab byl.wafa menawi
Parasitic female lives in the small intestine in the epithelial mucosa and the crypts of Lieberkühn. para-lab byl.wafa menawi
Autoinfection • Some known triggers/inducing conditions: • 1. Corticosteroids (prednisone) • 2. Immunosuppression • 3. Neonatal infections • 4. Infections with transplanted adults • 5. Massive initial infections • 6. Intestinal stasis para-lab byl.wafa menawi
Determinants: • 1. Immune status of the host • 2. Environmental parameters • 3. Presence of food para-lab byl.wafa menawi
Strongyloides Life Cycle parthenogenesis FECES SOIL para-lab byl.wafa menawi infective larvae
Route of migration through the body: • The scramble hypothesis - any route that leads to the small intestine. • Migration starts with a “layover” in the skin (1 to 2 days). • + Migration from the skin takes ~4 days. • = 5 - 6 days to reach small intestine. • L4 ~ 2days. • Young adults in intestine at 7 days post-infection. • L1 in feces by 10 to 14 days post-infection. para-lab byl.wafa menawi
Filariform larva (approximately 550 μm in length) and an immature adult worm (1.3 mm) recovered from the feces of an immunocompromised dog experimentally infected with Strongyloides stercoralis. It is extremely rare to recover from the stools of immunocompetent patients any S. stercoralis stages other than the shorter (approximately 300 μm) and plumper rhabditiform larvae (right upper corner inset) para-lab byl.wafa menawi
Eggs are embryonated(L1) when laid. para-lab byl.wafa menawi
Intestinal muscularis mucosae and submucosa with a full-length section of a penetrating filariform larva. para-lab byl.wafa menawi
GI Manisfestations • • Epigastric abdominal pain • • Postprandial fullness • • Heartburn • • Brief episodes of diarrhea • • Malabsorption para-lab byl.wafa menawi
Pulmonary manifestations • • Diffuse bronchopneumonia • • Intra-alveolar hemorrrhage para-lab byl.wafa menawi
Haemoragic pneumonia in disseminated S stercoralis infection para-lab byl.wafa menawi
Cutaneous Manifestations • • Uricarial rashes • • Migratory dermatitis • • Periumbilical cutaneous purpura para-lab byl.wafa menawi
Migrating larvae of Strongyloides stercoralis in skin para-lab byl.wafa menawi
Diagnostic challenges • A fatal disease in immunocompromised and lifelong autoinfection • Intermittent larval excretion • Insensitivity of standard lab techniques (preserved stool concentrations, charcoal culture) • Insensitivity of our best larva finding technique (agar plate) • Non-specificity of standard strongyloides serologies para-lab byl.wafa menawi
Strongyloides Stercoralis • Diagnosis • Parasite found in feces, sputum, duodenal aspiration, CSF, tissue biopsy para-lab byl.wafa menawi
Stronglyoides Infection • Treatment • oral Ivermectin 200 ug/kg daily x 2 days, Albendazole as alternative • Prevention • CDC recommends oral Ivermectin 200 ug/kg daily x 2 days for prevention in immunosuppressed para-lab byl.wafa menawi
thank you para-lab byl.wafa menawi