Mycobacterioses(tuberculosis,leprosy,atypicalmycobacterioses,paratuberculosis,andperhapsCrohn’sDisease)aretheinfectiousdiseasesofmenandanimalswiththelargestdiffusiononearth.Theinfectiousagentsoftuberculosisareacid-resistantrod-likeformedbacteriaofthefamilyMycobacteriaceae,genusMycobacterium.ThegermwasdetectedbyRobertKochin1882.Owingtotheveryhighinfectiouspowerofpathogenicmycobacteria,earlydiagnosisisessentialtopreventspreADIngofthedisease.Convergenceofvariousapproachesarenecessarytocontrolthemycobacterioses,immunereactionsandbacterialsheddingbeingvariableduringthediseases.However,usualdiagnosticprocedureswereuptonowunsatisfactoryanddidnotallowdistinguishingamongdifferentmycobacteriaspecies.Theillnessisnormallytransferredbydropletsofsalivafrominfectedpersons.Thetargetoftheinfectionaremostlythelungs,butalsootherorganslikethebrain,intestinaltract,bones,lymphnodesandkidneyscanbeafflicted.Tuberculosisisnotonlyfoundindevelopingcountrieswith8millionofnewinfectionsyearly,butalsoinindustrializedcivilizations,asanactualdiseasewithsomethousandsofcasesyearly.Withouttreatment,thediseaseleadsin50%ofthecasestodeathwithinlessthantwoyears.Clinicalsymptomsarefatigue,lossofweight,lackofappetite,lightfever,nocturnalsweatandpaininthechest.EspeciallypatientswithHIVarethreatenedbytuberculosisduetotheirimpairedimmunesystem.AvaccinationwithlivingattenuatedbacteriaispossIBLe(BCG=BacilleCalmetteGuérin).Thisismostlydonewithnewbornoryoungchildren.Witholderpatients,beforethevaccinationthereisnormallyperformedthetuberculintest(PirquetorMantoux),whereasmallamountoftuberculinisinjectedundertheskin.Inapositivecase,thereexistantibodiesagainstMycobacteria,andavaccinationisnotnecessary.Uptorecently,therehavenotexistedanySEROlogicalmethodstodetecttuberculosisantibodiesinserum.Theonlyavailableprocedurewasbesidestheskintuberculintestthedirectmicroscopicalidentificationofthedyedbacteriainsputum.Meanwhilespecificantigenshavebeenpreparedeitherbypurificationofnaturalmaterialorbyrecombinantmethods.ThisELISAtestkitforthedeterminationofIgGantibodiesusesacocktailofhighlypureproteinsinordertodetermineanimmuneresponseagainstthebacteriainhumanserum.AfreshorchronicallyactiveinfectioncanbediagnosedbyIgAandIgMtests,whicharealsoavailable.