SectionalProceedingsoftheRoyalSocietyofMedicineVol.XXXpage183sectionof - PDF document

SectionalProceedingsoftheRoyalSocietyofM
SectionalProceedingsoftheRoyalSocietyofMedicineVol.XXXpage183sectionofComparativelebi)ccinePresident-GEORGEW.DUNKIN,M.R.C.V.S.[October28,1936]ParatuberculosisofCattleandSheepPRESIDENT'SADDRESSByG.W.DUNKIN,M.R.C.V.S.PARATIJBERCULOSISisaconditionmetwithincertainspeciesoftheloweranimalsonly,andisnot,asfarasourknowledgestandsatpresent,communicabletoman.Paratuberculosis,orJohne'sdisease,asitismorecommonlycalledinthiscountry,isessentiallyabovinecondition,butithasalsobeenrecordedindeer,sheep,swine,andgoats.Ithasnot,sofar,beendetectedinthehorse,andnoonehasyetsucceededintransmittingittoanyofthesmalllaboratoryanimals.Boquet(1925),someyearsago,attempteditspassageintowhiterats,butafteralengthyincubationperiodduringwhichtimenoneofhisratsexhibitedsymptomswhichmighthavebeeninterpretedasthoseofexperimentalJohne'sdisease,hisratswerekilledandthepost-mortemexaminationrevealednogrosslesionsotherthanafewpin-headareasintheomentum.Ihaverepeatedthisexperiment,andalthoughmyratslivedfortwoyears,thepost-mortemexaminationwasidenticalwiththatdescribedbyBoquetandgrosserlesionswerenotobserved.Thesmallpin-headareasseenintheomentum,butnotelsewhere,werecalcareousincharacter,andwhenfinelygroundinanagatemortarandexaminedmicroscopically,wereseentocontaincountlessnumbersofacid-fastorganismsidenticalwiththoseassociatedwithJohne'sdisease.Thebovinedisease.-ThenaturallyoccurringdiseaseincattleismoreorlessgeneralthroughouttheUnitedKingdom,France,Germany,Holland,andItaly.IthasalsobeenseeninNewZealandandAustralia.InIndiaitisalsonotunknownandpersonalreportsofcaseshavereachedmefromSouthAfrica.Theadvancedclinicalcaseisrecognizedbytheprogressivewastingofthepatientaccompaniedbyapersistentdiarrhceawhichitisalmostimpossibletocheckbytherapeuticmeans.Emaciationbecomesafeatureandeventuallytheanimalisunabletorisefromtherecumbentposition.DEC.-COmP.MED.1I'll,I84ProceedingsoftheRoyalSocietyofMedicine2Post-mortemexaminationofthetypicalcaseshowsthepresenceofconsiderablethickeningoftheintestinalmucosawhichisalsousuallymuchwrinkledinappear-ance.Theassociatedlymphaticglandsareenlargedandonsectionexudeadark,wateryfluidleavinglacunainthestructureoftheincisedgland.Thecausalorganismisanacid-alcohol-fastbacillusfirstdescribedbyJohneandFrothinghamin1b95;butTwortandIngram(1913)firstsucceededingrowingitonanartificialmedium.Thereisnodoubttheseauthorsrecognized,thatunlessitwasproperlystudiedandadequatestepsweretakentopreventitsspread,thediseasewasanexceedinglyseriousonetothestock-owner.Unfortunatelytheyreceivedlittleornoencouragementandforsomeyears,apartfromattemptsatcure,aseriousstudyoftheconditiondidnottakeplace.Meanwhileitsspread,aforegoneconclusion,continued,andreachedsuchapassthatmanyfarmershavebeenputoutofbusinessonthisaccountalone,losingasmanyastwentyormoreanimalsayear.InthisconnexionitseemsappropriatetoquoteHagan,whoinapronounce-mentmadelastyear,saidthatthediseaseisslowlybutsurelyspreadingamongAmericancattle-afa

ctthatisnotsufficientlyappreciated.Theor
ctthatisnotsufficientlyappreciated.Theorganismsarepresentinthefecesofadvancedcasesandthisfactalonewillindicatethenatureoftheproblemsetthestudentofpreventivemedicineindealingwiththecondition.Onfarmswherethediseaseexiststhecowbyres,pasturesandpondsareallpotentialsourcesofinfectionduetocontaminationbyopencases,andconsequentlybecomedangerstothehealthymembersoftheherd.Theorganismispeculiarlyresistanttodisinfectantsandsurvivesinmoistsurroundingsformanymonths.Sunlightanddesiccationappeartoretarditsgrowthandmaycauseitsdeath.Post-mortenmexamination.-Intheadvancedcasetheonlymacroscopicevidencesofthediseasearethosealreadyreferredto,butintheearlycaseeventhickeningandcorrugationoftheintestinalmucosamaybeabsent,andtheonlyrecognizablesignsofdiseasemaybeanenlargedandcedematousileo-coecalvalvewhichmaybemuchinflamed.Soconstantlyhavethecausalorganismsbeenisolatedfromtheintestinalwallthatatpost-mortemexaminationithasbeencustomarytorestrictattentiontothisregion.Ithas,indeed,beenstatedbysomeobserversthatthissiterepresentstheonlyorgansaffected,butitisnowrecognizedthatthisisnotthecaseandthatthediseasemaybemuchmoregeneralized.Carefulroutineexaminationofthelymphaticsystemofanimalsdeadoftheadvanceddiseasehasdemonstratedclearlythatthepharyngeal-andsometimesthesubmaxillary-glandsmayharbourthebacillus,andwhenitisrecalledthatprobablythemostcommonmethodofinfectionisbythemouth,thisisnotremarkable.Itis,Isuppose,humannaturetoharbourfeelingsofincredulitywhenstate-mentsaremadewhichdonotappeartocoincidewithourownviewsandopinions,andthepublicationin1929,byAlexejeff-Goloff,oftheresultofhisexperimentsonJohne'sdiseasemaybesaidtobeanexample.Thisauthorstatedthatfromfouradvancedcasesofthediseasehehadisolatedthecausalorganismfromthefollowingorgansandbodyfluids:heart-blood,peripheralvessels,heartmuscle,gall-bladder,urinarybladder,ovaries,mesentericglands,suprarenals,kidneys,liver,andspleen,aswellasfromtheuterusofacowinthethirdmonthofpregnancy.Heconcludedthatthediseaseonoccasionmaytaketheformofabacteremiainthecourseofwhich,inpregnantanimals,intra-uterineinfectionoccurs.Suchastatermentpresupposestheoccurrenceofcongenitalcasesandthisisprobablythecaseaswasinstancedsomemonthsagoinareport(Dunkin,1935)whichdescribedsuchanoccurrence.SectionofComparativeMedicineDiagnosis.Thediagnosisoftheclinicalcaseisrelativelysimple.Diarrhceaisaprominentsymptomandisaccompaniedbyaprogressivewastingofthemusculature,particularlyofthehindquarters.Thereisinmanycasesanaromafromtherecentlypassedfreceswhichisalmostcharacteristic.Acid-alcohol-fastorganismscanbedemonstratedintheftecesandhere,aswellasinscrapingsfromthemucousmembraneoftheintestine,thereisatendencyforthemtocollecttogetherinclumps.Thedifficultyofdiagnosingtheveryearlyandnon-clinicalcasehas,inmyopinion,beenthegreatstumbling-blocktofurtherprogressintheinvestigationofthisdisease.Theresistanceofthecausalorganismtoaccommodateitselftoavarietyofartificialmediahas,inthepa

st,delayedtheproductionofanysubstancewhi
st,delayedtheproductionofanysubstancewhichmighthaveprovedvaluablewhereanallergictestwascontemplated.TwortandIngram(1912)werethefirsttorecordthatforitsgrowthonartificialmediathepresenceofsomeotheracid-fastorganismoranextractpreparedtherefromwasnecessary,andtheydescribedthisfactorthe"essentialsubstance".Theymadeuseof1M.tuberculosisandM.phlei.Incertainmediacontainingasuspensionofoneorotheroftheseorganismsgrowthwaspossible,thoughslow.Fromsuchculturestheyproducedadiagnosticagentwhichtheycalled"Johnin",butwhenitwasmadefromculturesinwhichdead111.tubercutlosishadbeenpresent,aseriousdifficultyaroseinthatpositivereactions,althoughobtainedincasesofJohne'sdisease,werealsoseenincasesoftuberculosis.Itwasforthisreasonthattheuseofthisorganismasasourceofthe"essentialsubstance"ofTwortandIngramwasdiscardedandIll.phlei-anon-pathogenicacid-fastbacillus-wassubstituted.AnotherphaseofopiniongainedcurrencyatthistimeandaviantuberculinwasusedfairlygenerallyforthediagnosisofJohne'sdisease.ThiswasprobablyduetothefactthatatonetimeJohne'sdiseasewasthoughttobecloselyalliedtoaviantuberculosis,ifnottobetheactualdisease.Evento-daytherearestillmanywhoadheretothismethodofdiagnosis,butitpossessessimilardrawbackstothediagnosticagentdiscussedabove,inthatcattlesufferingfromaviantuberculosis-bynomeansuncommoninthiscountry-willreacttothisagenteventhoughtheyarenotthesubjectofJohne'sdisease.Thisunsatisfactorystateofaffairscontinueduntilafewyearsagowhentherewaspublished(Dunkin,1928)anarticleinwhichwasdescribedamethodofcultivationonacomplexbrothfromwhichitwasallegedapotentJohnincouldbeprepared.Thepreparationofthisagentwasdescribed,asalsowereitsmethodofapplicationanditsreactionsonaffectedandnormalanimals.Forsomeyearsitwasfairlywidelyused,butittoofellfarshortoftheideal,inasmuchasthecomplexnatureofthenutrientbrothonwhichtheorganismsweregrownsetupconsiderablenon-specificswellinginnormalanimals,andinthehandsofanoviceandsometimesinthoseofmenofexperience,muchdifficultywasexperiencedindecidingwhetherornottheanimalundertestwastobedescribedasnormaloraffected.BecauseofthisdifficultyseveralattemptsweremadebyvariousworkerstocultivatetheorganismonasyntheticmediumandthatofSautonreceivedmuchattention.In1931Iwasprivilegedtosee,duringavisittotheUnitedStates,theresultofattemptsatartificialcultivationbyDeanHaganofCornellUniversity,who,atthattime,wasusingthemediumdescribedbyHenley(1929)inconnexionwiththeartificialcultivationofM.tutberculosis.WiththismediuminwhichwasincorporatedthedeadbodiesofM.phlei,Hagansucceededinobtainingfairlygoodgrowthinamatterofthreeorfourmonths,andfromthishepreparedaJohninwhichheclaimedwaspotentandsatisfactoryasadiagnosticagent.Itisnowpossibletocultivatetheorganismonthismedium(Dunkin,1933)and,Ibelieve,onothersyntheticmedia,withouttheaidofthedeadbodiesofM.phleiorofanyotheracid-fastorganism.Nevertheless,artificialcultivationinthiswayisnotthesimplemethodit38586ProceedingsoftheRoyalSocietyofMed

icine4appearstobefromsuchabaldstatement.
icine4appearstobefromsuchabaldstatement.Theorganismmustbeeducatedthroughmanylongandlaboriousstagestoexistandmultiplywithoutsubstanceswhich,onisolationinprimaryculture,appeartobeessential-aprocedurewhichmaywelltakesomeyearsor,atanyrate,manymonths.Thisorganismisindeedthemostdifficultoftheacid-fastbacillitotraininthismanner,andKnight(1936)describesitinthefollowingwords:"Theprocessofthistrainingwouldappeartoconsistintheorganismsbecomingabletosynthetizeforthemselvesthespecialsubstancewhichtheynormallyobtainfromtheirhostwhengrowingparasitically,andwhichordinarily(i.e.beforetraining)mustbegiventothemforgrowthinvitrointheformofotheracid-fastbacilliwhichcansynthetizethesubstance."Johnin,preparedfromtheproductsofsuchculturesandconcentratedbyheatorothermethods,hasbeenprovedafairlyreliablediagnosticagentandcanbeusedsimultaneouslywithtuberculinonthesameanimal,withouteitherreagentinterferingwiththeactivityoftheother(Dunkin,1935).Othermethodsofpreparingadiagnosticagenthaveappearedfromtimetotime.AnAmericanproduct(Wright,1928)forwhichmuchsuccesswasclaimedpossessedoneseriousdrawback-thetediousandtime-consumingnatureoftherecommendedtechnique.Itconsistedoftheintravenousinjectionoftheproductandthesubsequentrecordingofhourlyrectaltemperaturesforsometwelvebours.Vall6eandRinjard(1926)recommendedtheuseofawateryextractoforganismsgrownonthesurfaceofsolidmediaandappliedbytheintradermalroute.MorerecentlyIhavesecuredapotentJohninbyotherprocedures.MatureculturesonthesurfaceofHenley'ssyntheticmediumarecollectedandfilteredthroughpaper.ThemassisthencollectedanddriedinvacuooverP205,andissubsequentlygroundinaballmillcontinuouslyforfourteendays.Afterthismostoftheorganismsarenolongerrecognizablebymicroscopicexaminationandhavelosttheiracid-fastcharacteristics.Thepowderedorganismsarethencollectedandimmersedforseveraldaysincoldwater,inavesselcontainingglassbeads.Thisisvigorouslyshakentwoorthreetimesadayuntilthecolourofthefluidapproachesalightbrowntint.AtthisstagethewholeisfilteredthroughaBuchnerfunnelwithtwolayersoffilterpaper.Theproductistitratedroughlyonaffectedcattleinordertoarriveatanapproximateestimateofitspotency.Adecisionismadeonthistestwhetherornotconcentrationisnecessary,andreductiontohalforlessoftheoriginalvolumeonawaterbathmaybeindicated.TheultimateproducthasbeenfoundtobeaspotentasJohninpreparedintheorthodoxway.TheadvantageofthismethodisthatalargersupplyofJohninissecured,anduseismadeoforganismswhichhadpreviouslybeendiscarded.ThesuccessorfailureoftheJohnintest,ascarriedoutbythedoubleintradermalmethod(officiallyrecommendedinthiscountryfortheapplicationofthetuberculintest[1925]),dependsmainlyontwofactors,namely,(1)thepotencyoftheproductand(2)thestateofsensitivityofthetestedanimal.Intheserespectstheproblemisthesameasthatencounteredinattemptsattheearlydetectionoftuberculosis,andineithercaseitisquiteuselesstoexpectgoodandacceptableresultsiftheproductusedisnotofhighpotency.Inthecaseof

tuberculintheguinea-pigmaybeusedasthetes
tuberculintheguinea-pigmaybeusedasthetestanimal,butwheretheproductconcernedisrequiredforveterinarypurposesitisdesirablethatbovinesaswellasguinea-pigsshouldbeused.InJohne'sdiseasewearefacedwiththeinitialdifficultyofhavingnosmalllaboratoryanimalsusceptibletothedisease,andaffectedbovinesaretheonlytestanimalsthathavesofarbeenusedforthispurpose.Recently,bowever,ithasbeenfoundthatartificiallyinfectedgoatstreatedbyintravenousinjectionwithlargedosesofculturesrespondadequatelytotheJohnintest(Dunkin,unpublished).Itisnecessarytodelayinitialtestingforaboutthreemonthsafterinfection,butgoatstreatedinthiswaycanprobably5SectionofComparativeMedicine87beusedforseveralyears.Theadvantageofgoatsforthispurposewillatoncebeappreciated,fortheynotonlytakeuplessroomthancattle,butarelesscostlytomaintain.Complement-fixationtest.IbelievethatTwortandIngram(1913)werethefirstworkerstoinvestigatethepossibilitiesofthismethodofdiagnosisinJohne'sdisease,andinthesameyearBangandAndersen(1913)conductedamuchlargerseriesofexperiments,usingavarietyofantigens.Theysecuredthebestresultswhenhumantuberclebacilliwereused,andtheyfoundthatwhenJohne'sbacilliwereusedresultswerenotsosatisfactory.Aseriousdrawbacktothismethodistheextremelikelihoodoftuberculouscasesalsogivingapositiveanswer.Sincethattimethetechniqueofthetesthasgreatlyimproved,andHaganandZeissig(1933)studiedthequestionanew.Insecuringasatisfactoryantigen,theseauthorsencountereddifficultiesnotunknowntoothers,andwhileinthefirstinstancetheymadeuseofpartiallydefattedhumantuberclebacilliforthispurpose,theysubsequentlyadoptedthemethodofWitebsky,KlingensteinandKuhn(1931).Theyfoundthatthetestwaspositiveincaseslongbeforesymptomsappearedandremainedpositiveuntildeath,anditwasascertainedthatitsmostusefulservicewasincaseswhereadvanceddiseaserenderedtheapplicationoftheallergictestunreliable.Idonotbelievethatsatisfactoryresultsarelikelytobeseenfromnthismethodoftesting,solongastheantigenusedispreparedfromorganismsotherthanthoserecognizedasthecauseofthedisease.Cross-resultsarealmostcertaintooccur,anditisnotunlikelythatasmallernumberofpositivecaseswillyieldsatisfactoryresults.InmyownendeavoursinthisfieldofworkIhavehadthebestresultswhenusinganantigenpreparedfromdriedandball-milledorganismsgrownonmediainwhichnootheracid-fastbacilluswasincorporated.Thepowderedorganismsaresuspendedinwaterandheatedat650C.forhalfanhourandallowedtostand.Thesupernatantfluidisusedastheantigen.Inmyhandsfixationofcomplementwasusualinabout80%ofcasesofJohne'sdisease.Atthesametimeseveralcasesofopentuberculosishavebeenencounteredinwhichfixationofcomplementwasseen,andyetonpost-mortemexaminationnomacroscopicsignsofJohne'sdiseasecouldbedetected.Atthetimethisworkwasbeingconductedexhaustiveexaminationoftheskeletallymphaticsystemwasnotcarriedout,anditispossiblethatsomeearlycasesweremissed.Nevertheless,itmustbefranklyadmittedthatthecomplement-fixationtest,bywhatevermethodapplied,isasyetnotareli

ableorsatisfactorymethodofdiagnosisexcep
ableorsatisfactorymethodofdiagnosisexceptinsofarasitmaybeusedtoconfirmtheallergictestpreviouslycarriedout.Incubationi.-Theincubationperiodofthediseaseisknowntobeverylong-manymonthsandpossiblyyears-afactwhichincreasesthedifficultiesineradica-tionschemes.Onecasewasrecentlyreported(Dunkin,1935)inwhichitappearedthatthediseasewascertainlycongeniital,andifthiswasthefacttheincubationperiodwasthreeandhalfyears.Prevention.-Johne'sdiseaseisbothinterestingandimportantinthestudyofpreventivemedicinefor,aswithmostdiseasesofanimalsandespeciallyfarmanimals,theeconomicsituationhastobeborneinmind.Variousmethodsofvaccinationhavebeenattempted,butwithnosuccess,andthatwhichseemedatonetimethemostpromisingwaspreparedbyMeissnerandKohlstock(1912).Theseworkersusedthescrapedmucousmembraneoftheintestinefromaffectedanimals,andtreateditwithantiformin,andtheresultantmixturewaswellshakenwithglassbeadsandthenfiltered.AfterpHadjustmentthefiltratewasusedasavaccine.Thisworkwaspublishedin1912,butnothinghassinceappearedto88ProceedingsoftheRoyalSocietyofMedicine6indicatethattheprocedurehadanyrealandlastingvalue.ThedifficultiesinconnexionwithanyattemptatvaccinationagainstJohne'sdiseasearenotunlikethosemetwithintuberculosis,butinanycaseitistruetosaythatthereisto-daynomeansofvaccinationagainstthedisease,whichisoftheslightestvalue.Theresistanceofferedbytheorganismtodisinfectantsandagentsordinarilylookeduponaslethalformostbacteriaraisesimmensedifficultieswhentreatmentofpasturesiscontemplated.Twentypercent.antiforminforhalfanhourdoesnotdestroytheseorganisms,andtheyappearunharmedafterimmersionin10%coppersulphateforsixhours.Twenty-fourhours'exposureofacultureinanatmosphereofsulphurdioxide,ofaconcentrationwhichwouldprobablykillguinea-pigsandratsinfifteenminutes,haslittleornoeffectontheirvitality.Probablythemostsatisfactorymethodofdealingwithinfectedpasturesistheapplicationoffreshquicklimeinamountsvaryingwiththecharacterofthesoilfromonetotwotonsanacre.Whenappliedinthisconcentrationindryweatheritisknownbyexperimentthatatemperatureashighas700C.maybereached,andexposureatthisdegreeofheatforfiveminuteswilldestroyM.paratuberculosis(Johne'sbacilli).Atthisstagethebestandmosthelpfullineofattackinattemptingtoeradicatethisdiseasefromourherdsshouldbeconsidered.Firstly,itisclearthatanvsuccessfulmethodmustbenationalincharacterandconceptionandnotconfinedtoindividualfarms,districts,orevencounties.ItisforthisreasonthatonefeelsdisposedtofavourtheadmissionofJohne'sdiseasetothelistofscheduleddiseases,somakingitofficiallyrecognized.Itispossible,Ithink,tocarryoutsatisfactoryeradicationmeasuresbythedestructionofallopencasesandthestrictisolationofallpositivereactorsuntilparturitionhasoccurredortheanimalsarefitforslaughter.Isolationofsuchcasesisdifficultbutnotimpossible,forinstanceshaveoccurredwherecaseshavebeenkeptforyearsononepartofafarm,whileonanotherparta"tubercleandJohnefree"herdhascontinueditsuninterruptedcourseofb

reedingandmilkproductionforsomeyears,wit
reedingandmilkproductionforsomeyears,withouttheoccurrenceofeitherofthesediseases.Suchmeasureswouldnotbepossibleinallcases,butinonlyafewwilltheybeimpossible,andthenothermeanswouldhavetobedevised.Thesheepdisease.Thetitleofthisaddressis"Paratuberculosisofcattleandsheep"and,asstated,themoreusualnameforthebovinedisease,inthiscountryatanyrate,isJohne'sdisease.Adiseasehavingmostofthecharacteristicsofthebovineconditionisseeninsheepandhasbeendescribedbyvariousauthors.Stockman(1909and1911)firstrecordeditinthiscountry,andregardeditasJohne'sdiseaseofsheep.InthefirstofhistworeportsStockmansuggestedthattherewasapossibleconnexionbetweenitandscrapie(adiseaseofsheepseenontheeasternbordersofScotlandandNorthEngland)butinhissecondreport,publishedtwoyearslater,itwasarguedthatsubsequentobservationdidnotwarranttheconclusionthatthediseaseknownasscrapieisaformofJohne'sdisease,asitispossiblethattwodifferentdiseasesmaysometimesaffectthesameanimal.ItisfurtherstatedthatthreesheepexaminedbyStockmanshowedthecharacteristicskinirritationofscrapiebutinonlyonecoulddistinctlesionsofJohne'sdiseasebefound,andinanimalsaffectedinaniotheroutbreak,classicalsymptomsandlesionsofJohne'sdiseasewereobserved,butnoirritationoftheskinwasnoted.Ihavebeenabletoconductaninvestigationintothisconditionintwoflocks,oneofwhichwasvisitedandinspected.Inthelattercasetheskinirritationrecognizedasasymptomofscrapiewasevidentinthemostadvancedcases,andthewoolwasSectionofComparativeMedicineeasilypulledout,leavingacompletelybarepatchofskin.Lossofconditionwasrapidanddiarrhoeawasevident.Thereare,howsever,twofeatureswhichraisedoubtsastowhetherthesheepandthecattlediseasearethesame.Theorganismsseeninthesheepdisease,althoughacid-alcohol-fast,maypossesscertainmorphologicaldifferencesfromtheJohne'sbacillusencounteredinthebovinedisease.Althoughtheycertainlyshowatendencytoclumpformation,theirarrangementisreminiscentratherofthedistributionseeninratleprosy,andtheorganismsareoftenlongerandmoreslenderthanthoseseeninJohne'sdiseaseofbovines.TheprincipalcharacteristicwhichsuggeststhatthediseaseisprobablynotJohne'sdiseaseistheextremedifficultyexperiencedinattemptsatartificialcultivation.Seventoeightmonthsseemstobetheusualtimewhichmustelapsebeforeprimaryculturesareseen(Balfour-JonesandDunkin,1935)andeventhenonlyaproportiongrow.Itisperhapsasomewhatboldassumption,butIthinkthatwhileitisclearthatthereexistsaconditioninsheepandcattlewhichmaybeproperlycalledparatuberculosis,thetwodiseaseshavecertaindifferenceswhichwarranttheconclusionthattheyarenotthesamedisease.Inaconditionpresentingsuchdifficultiesasparatuberculosis,itisnoteasytosuggestameanswherebythispointcanbesettled.Branch(1933)studiedvarioustypesofacid-fastorganisms,otherthanmammalianformsofM.tuberculosis,whichhehadisolatedfromhumanpatients,andhefoundthattheirintraperitonealinjectionintowhitemiceprovidedausefulaidindifferentiatingacid-fastbacteriawhichwereneithertruetuberclebacillin

orsaprophytes.InBranch'shands,suchorgani
orsaprophytes.InBranch'shands,suchorganismsprovokedmultipleabscessesinthekidneysoftheinjectedmice,whereasrealtuberclebacilliortruesaprophytesdidnot.Feldman(1935)conductedasimilarseriesofobservationswithorganismsobtainedfromcattle,buthedidnotmeetwiththesuccessachievedbyBranch.MiceinoculatedwiththeorganismsisolatedbyFeldmanfailedtoproduceanephritis,andheconcludedthathisorganismsweretruesaprophytes.Theorganismwhichwebelievetobethecauseofovineparatuberculosishasnotsofarbeenusedinthismanner,butsuchanexperimentmightservetodifferentiateitfromthebovineorganismandmightwellbeattempted.AlthoughthediseaseswhichIhaveonlypartiallydealtwitharenotcommunicabletoman,theyhavepointsofinteresttobothbranchesofmedicine.Ihavefoundthestudyoftheacid-fastgroupoforganismsoneofabsorbinginterest,foreachmemberofthegrouppossessescharacteristicsdifferentiatingitfromanother.Itiscuriousthatpracticallyallthenon-pathogenicacid-fastorganismsgrowwithremarkableeaseonmostmedia,andinmanyofthemmultiplicationismacroscopicallyevidentintwenty-fourhours.Thesameassertioncannotbemadeofthedisease-producingorganismsofthisgroup.Allthosewhichhavesuccumbedtotheartofmanandcannowbecultivatedartificiallydosowithareticence,varyingwiththeindividual,whichwouldbecommendableinothercircumstances,andinothers,notablytheleprosybacillus,theobjectiontoaninvitrotypeofexistenceissostrongastoamounttobluntrefusaltohaveanythingtodowithit.IfImaybeexcusedforpassing,evenmomentarily,intotherealmsoffantasyandconjecture,Iamtemptedtoaskmyselfifsuchremarkabledifferencesasadmittedlyexistamongorganismshavingsomuchincommonmaynotbesignificant.Anydenialofsuchaseeminglyfar-fetchedtheorymustofnecessitybesimilarlyfantastic,andonlytheresultsoffurtherscientificendeavourcanclarifywhatisto-dayasomewhatcloudyatmosphere.78990ProceedingsoftheRoyalSocietyofMedicine8REFERENCESALEXEJEFF-G*LOFF,N.A.(1929),Ztschr.f.Infektionskr.,36,313.BALFOUR-JONES,S.E.B.,andDUNKIN,G.W.(1935),T.Conzp.Path.andTherap.,48,236.BANG,O.,andANDERSEN,C.W.(1913),Zentralbl.f.Bakt.,Abt.1.Orig.69,517.BOQUET(1925),Compt.rend.Soc.debiol.,93,219.BRANCH,A.(1933),Tubercle,14,337.DUNKIN,G.W.(1928),J.Comp.Path.andTherap.41,1.Id.(1933),Ibid.,46,169.Id.(1935),Ibid.,48,36.FELDMAN,W.H.(1935),J.Am.Vet.M.A.,88,166.HAGAN,W.A.,andZEIssIG,A.(1933),Ibid.,82,391.HENLEY,R.R.(1929),Am.Rev.Tuberc.,19,660.JOHNE,andFROTHINGHAM(1895),Deut8cheZtschr.f.Tiermnedizinundvergleich.Path.,Bd.21,S.438.KNIGHT,B.C.J.G.(1936),Med.Res.CouncilSpec.Rep.Series,No.210.MEISSNER,andKOHLSTOCK(1912),Berl.Tierarstl.Wchn8chr.,No.25,p.450.ReportofTuberculinCommitteeappointedbyMed.Res.Coincil(1925),Spec.Rep.Series,No.94.STOCKMAN,S.(1909and1911),Reps.ChiefVet.Off.Bd.Agric.andFisheries,Ann.Reps.andProcs.TWORT,F.W.,andINGRAM,G.L.Y.(1913),"AmonographonJohne'sdisease",London.VALLF.E,H.,andRINJARD,P.(1926),Rev.Gin.Mid.Vit.,35,1.WRIGHT,H.K.(1928),J.Am.Vet.M.A.,72,1036.WITESEKY,E.R.,KLINGENSTEIN,andKUHN,H.(1931),Klin.Wchnschr.,10