Strongyloides

Nomoxiur, Thiben2ole, Tiabenda, Triasox, TBZ and Strongyloides stercoralis) ... 

The direct wet mount made from unconcentrated fresh feces is most useful for the detection of the motile trophozoites of intestinal protozoa and the motile larvae of Strongyloides spp. It is also useful for the detection of protozoan cysts and helminth eggs. For fixed feces, the direct wet mount may allow the detection of parasites which do not concentrate well. This method is also useful for the examination of specific portions of feces, such as flecks of blood or mucus. 

The Baermann concentration technique has greater sensitivity for the detection of strongyloides larvae than do the standard concentration techniques described above. This technique is useful clinically for the diagnosis and monitoring of therapy of strongyloides infections, and it is useful epidemiologically for the examination of soil for the larvae of nematode parasites. 

Larval maturation studies, sometimes referred to as cultures, can be performed on fecal specimens applied to wet filter paper. Nematode larvae such as Strongyloides spp. or hookworm mature to the filariform stages in the culture container and migrate from feces into water, where they are detected microscopically. The procedure can be performed in a petri dish with a square of filter paper or in a large test tube with a strip of filter paper. 

Examine the specimen on days 3, 5, and 7. Strongyloides filariform larvae are found on days 2 and 3, and hookworm larvae are found on days 5 through 7. Larvae are identified by their morphological characteristics. 

Urine specimens usually are examined for the eggs of Schistosoma haemotobium or the trophozoites of Trichomonas vaginalis, although occasionally the larvae of Strongyloides stercoralis may be found in patients with hyperinfection syndrome. Urine is the usual specimen for the diagnosis of Trichomonas infection in males. See below (Vaginal Material) for culture method. Urine is centrifuged, and the sediment is examined microscopically. 

Chilton, N.B., Gasser, R.B. and Beveridge, I. (1997a) Phylogenetic relationships of Australian strongyloid nematodes inferred from ribosomal DNA sequence data. InternationalJournal for Parasitology 27,1481-1494. 

Viney, M. (1994) A genetic analysis of reproduction in Strongyloides ratti. Parasitology 109,511-515. 

Viney, M.E. (1996) Developmental switching in the parasitic nematode Strongyloides ratti. Proceedings of the Royal Society of London, Series B 263, 201-208. 

Viney, M.E. (1999) Exploiting the life cycle of Strongyloides ratti. Parasitology Today 15,... 

Strongyloides ratti has two developmental routes in its life cycle (Fig. 5.1) and this developmental choice shows phenotypic diversity. The parasitic phase of S. ratti is a parthenogenetic female (Viney, 1994). Eggs that pass out of a host can complete the free-living phase of the life cycle by two alternative developmental routes, termed heterogonic and homogonic. In homogonic... 

Fig. 5.1. The life cycle of Strongyloides ratti. The progeny of the parasitic female can develop by two different routes, termed heterogonic and homogonic. L, larval stage.

Gemmil, AW., Viney, M.E. and Read, A.F. (2000) The evolutionary ecology of host-specificity experimental studies with Strongyloides ratti. Parasitology 120, 429-437. 

Schad, GA. (1989) Morphology and life history of Strongyloides stercoralis. In Grove, D.I. (ed.) Strongyloidiasis a Major Roundworm Infection of Man. Taylor and Francis, London, pp. 85-104. 

Viney, M.E., Matthews, B.E. and Walliker, D. (1992) On the biological and biochemical nature of cloned populations of Strongyloides ratti. Journal of Helminthology 66, 45-52. 

Korenaga, M., Hitoshi, Y., Takatsu, K. and Tada, I. (1994) Regulatory effect of anti-interleukin-5 monoclonal antibody on intestinal worm burden in a primary infection with Strongyloides venezuelensis. Journal of Parasitology 24, 951-957. 

Abe, T. and Nawa, Y. (1988) Worm expulsion and mucosal mast cell response induced by repetitive IL-3 administration in Strongyloides ratti-infected nude mice. Immunology 63, 181-185. 

Consider parasites Giardia Entamoeba histolytica Strongyloides stercoralis Cryptosporidium Cyclospora Isospora belli ... 

Wang CC, Nolan TJ, Schad GA, Abraham D Infection of mice with the helminth Strongyloides stercoralis suppresses pulmonary allergic responses to ovalbumin. Clin Exp Allergy 2001 31 495-503. 

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