EnzymeimmunoassayforthequalitativedeterminationofIgMantibodies
againstSchistosomamansoniinhumanserumorplasma
(citrateorheparin).Schistosomesbelongtotheclassofdistomas(trematodes).Theyrankamongthemostfrequentpathogens.
Estimationsoriginateinmorethan200millionaffectedpeople.Thematureparasitesare6–22mmlong.
ThemostimportantspeciesareSchistosomamansoni,S.japonicumandS.haematobium.SchistosomamansoniiscommoninAfrica,SouthAmericaandMiddleEast.Schistosomiasis(bilharziosis)is–dependingonspeciesandlocationoftheparasites–adiseaseoftheintestine,liverandspleenresp.urinarypassages.Humansare(re)infectedbycontactwithfreshwaterwhichiscontaminatedbyovacontainingurineorfaeces.Iflarvaeboreintohumanskin,firstatransientskinreactionappears(itchwithexanthemaorerythema,byrepeatedlyinfectioncercarialdermatitisispossIBLe).After3-10weeksthemeanwhilesexuallymaturewormssynthesizecytotoxicandallergicsubstanceswhichcoursefeverishreactioninhumans(Katayamafever).Theinfectedpersonismostlyharmedbytheeggs,whichgetintoorgansviabloodexcretingproteinsandglycoproteins.Thepersonreactsunderparticipationofownantibodiesandimmunecomplexeswithformationofgranulomaandgranulomatousproliferationinintestineandurinarybladdermucosa.Notexcretedeggsdieafter3weeksandwillbedissolvedorcalcified.Theaffectedtissuegetsfibrous.Infinalstagebilharziosiswillcausedead.