4 Microbiology الع نود البستنجي 19/11/2015 د. ناصر قبالن 1 P a g e
Intestinal Parasites (Helminthes) I will put the slides with Dr notes beside each one and the most important notes I will highlight them in Red color. Pictures are important for lab exam y Intestinal Helminths) worms) I.Platyhelminths)Flat worms ( 1 Cestodes (Tape-worms). 2 Trematodes) Flukes). and said: you might have one question about it II.Nematihelminths (Round worms /Nematodes) Cestodes (Tape worms ( well Taenia solium (Pork tapeworm) Taenia saginata (Beef tapeworm).cosmopolitan.human is the only definitive host incidence is higher in developing.countries - as 1000 per 1 Infection rate: as low as.10% high as * higher in developing area because of low higene 2 P a g e 23-Nov-14 NM Kaplan 9
Adults VERY IMPORTANT Table solium is more dangerous (serious), because it not just GI ifection, but also involved in serious condition "Cysticercosis) * solium has solar appearance, why we call it solium Notice : No hooks 14Nov--23 NM Kaplan 11 more uterus branches 14Nov--23 NM Kaplan 12 3 P a g e
Taeniid eggs indistinguishable.morphologically between spp 35rounded or subspherical,.µm 45x brown thick shell with peripheral radial striations eggs survive days-.months in environment : (empryonated) Mature oncosphere hexacanth pairs of 3 embryo with.hooklets Dr read all of the notes and they are important 14Nov--23 NMKaplan 13 Injection of India ink in uterus: Gravid proglottids with genital pores in mid-lateral position T. saginata T. solium * Important * notice the difference in gravid proglottid 14Nov--23 NM Kaplan 14 Life cycle About parasites about each one you should know : 1- caracterstic features 2- infective stage 3- number of hosts In the life cycle 4- food associated with it's position 4 P a g e to be able to diagnose, manage & choose D.O.C
Taeniasis.Light infections: asymptomatic Heavier infections: mild GI symptoms as abdominal discomfort, epigastric pain, nausea, vomiting & diarrhea and. weight loss Tinea : infective stage : cysticerci Food : Pork T.solium Breef T.saginata *larvae excyst : larve will brust and cysticerci will go out it. Dr read all of this slide Lab Dx 14Nov--23 NM Kaplan 16 Taeniasis :eggs or gravid proglottids in stool or from perianal area. Rx DOC :Praziquantel or niclosamide: single oral dose. Expulsion of scolex must be assured to assume satisfactory Rx Control Thorough inspection of meat ( pork & beef (Adequate cooking ) internal temp < 56C 5 / min )or freezing of meat ( cysticerci do NOT survive temps o > - 10C & < 50 o C. Adequate sewage disposal. Dr read all of the slide. * to make sure the drug is effective, Expulsion of scolex Cysticercosis Human (intermediate host) infection by T.solium eggs larval cysts in S/C tissue,muscle, heart, lungs & liver. CNS : meningo-encephalitic syndrome with eosinophilia &neurological disorders as epilepsy,psychiatry.! Eye : pain & visual disturbances & blindness. Dx :Hx of travel to endemic area,o&p in stool, immunology assays for specific Abs(useful epidemiological tools (,Radiology & Biopsy. Rx :Prolonged praziquantel or albendazole + steroids,surgery? Dr read the slide one by one,, So it's important. Human in -Teanasis is Definitive host, by eating animal's muscles contain cysticerci - cysticerocis is Intermediate host. T.solium eggs will enter then go anywhere to develop cysticercus. * surgery to remove the cysticercus 5 P a g e
T. solium Cysticercus 14Nov--23 NM Kaplan 19 Dr read the slide Diphyllobothrium latum (Fish tapeworm) Worldwide, endemic in subarctic & temperate regions in association with eating of raw or undercooked fresh water fish. Definitive hosts: human & many other mammals. *Remember, Red color are the most important otes of the slide Adults 23-Nov-14 NM Kaplan 20 10>-3(Longest tapeworm meters in length with.)proglottids 3000> reside in small intestine & attach to mucosa by only bilateral longitudinal 2 bothria) (sucking groves of their scolex w resembles two almond-.shaped leaves Scoelx Dr read the slide * Di = bilateral 2 bothria 14Nov--23 NM Kaplan 21 6 P a g e
Gravid proglottids passed in stool in strands.of variable length - 2mm wide X 12-10size: mm long 4 (Broader/wider than longer Broad.)tapeworm with ccc centrally positioned, rosette-.shaped coiled uterus genital uterine pore at.center of proglottid 14Nov--23 NM Kaplan 22 Eggs :)Immature (unembryonated discharged in small intestine from up to ( gravid proglottids.)eggs/ worm/ day1,000,000 5-6 weeks after.infectionpass in feces yellow-brown, oval or ellipsoidal, :µm( with40-51x76-58( arrows) (At one end, operculum.w can be inconspicuous At opposite (abopercular) end, small knob w can be.barely discernible mature under appropriate.)days 20-18 (conditions 14Nov--23 NM Kaplan *it called broad tapworm, because the gravid proglottid is broader than longer. * Tinea : uterus located medlateraly Diphelbothrium : uterus located centrally. 23 you should be familiar it pass immature, it need 2-3 weeks to become mature in appropriate condition Life cycle Dr read the slide برغوث : flea water الماء V.important infective stage : Plerocercoid larvae (mature larve) 7 P a g e
Diphylobothriasis Light infections: asymptomatic, nonspecific as loss of appetite, epigastric pain, abdominal cramps, vomiting, weight loss.some malnutrition & 12 Heavier infections: ccc vitamin B neurological &Megaloblastic anemia.problems Dr read the slide V.important specific ccc : decreament of Vitamin B12 in heavy infection by consumption of it 23-Nov-14 NM Kaplan 25 Dx Eggs & empty.proglottids in stool Rx.DOC: Praziquantel Control C for 10-Freezing at hours, thorough 48 cooking or pickling of. fish kills larvae Adequate sewage disposal to keep fish reservoirs free of.raw sewage Dr read the slide 23-Nov-14 NM Kaplan 26 Echinococcosis (Hydatid disease) Dr read the slide Causative agents: Echinococcus.granulosus & E. multilocularis 8 P a g e 23-Nov-14 NM Kaplan 27
Echinococcus granulosus common in Asia, Australia, Eastern Africa, southern Spain, southern parts of South America & northern parts of North.America per 1-2 incidence of human infection is population & higher in rural areas of 1000. endemic regions Dr read the slide * Epidemiology affected by hygene and geographics 23-Nov-14 NM Kaplan 28 smallest of all mm 9-3(tapeworms 3 long) with only.proglottids reside in small intestine of definitive & hosts; domestic wild carnivorous.)animals (dogs Adults * most important point smallest 14Nov--23 NM Kaplan 29 Eggs indistinguishable morphologically from. other Taeniid eggs 14Nov--23 NM Kaplan 30 9 P a g e
Hydatid cyst cm in diameter (although it may1-7 Round,.)cm30 grow up to consists of outer anuclear hyaline cuticula & inner nucleated germinal layer containing clear. yellow fluid Daughter cysts attach to germinal layer, although some cysts (brood cysts) may have only many larvae (protoscolices or hydatid.)sand 23-Nov-14 NM Kaplan 31 Fluid aspirated from hydatid cyst show multiple :protoscolices.µm 100 size -1.Ccc dagger-like hooklets Lt), (normally invaginated middle, then (& evaginate.rt) when put in saline Hydatid sand ** the most important lab diagnostic feature of is the presence of Dagger-like Hooklets 14Nov--23 NM Kaplan 32 Life cycle * the human is an accidentally infected ; if human is intermediate host, the cycle won't complete. because the human is the end stage of cycle. 10 P a g e
E.multilocularis In northern parts of Asia & North America. very similar morphology (1.2-3.7) mm & )life cycle with the following differences :definitive hosts are foxes &,to lesser extent dogs, cats, coyotes & wolves ;intermediate hosts are rodents ;cysts are multilocular (many chambers) &larval growth (in liver (remains indefinitely in proliferative stage invasion of surrounding tissues * E.multilocularis is restricted geographical associated. Echinococcosis (Hydatid disease).causative agents: E granulosus & E multilocularis Symptoms of slow-growing tumor with eosinophilia, : depend upon location of cyst.large abdominal cysts increasing discomfort.liver cysts obstructive jaundice.peribronchial cysts pulmonary abscesses Brain cysts intracranial pressure & Jacksonian. epilepsy.kidney cysts renal dysfunction.release of contents of cyst anaphylactic responses 19-Nov-15 NM Kaplan 27 Dx Intradermal (Casoni) test using hydatid fluid. Radiology: for pulmonary cysts & calcified cysts. Serology: ELISA or indirect hemagglutination test for Abs against hydatid fluid Ags. ** injection of hydatid fluid Ags then looking for any skin reaction 11 P a g e 19-Nov-15 NM Kaplan 28
Rx surgical removal of cyst or inactivation of hydatid sand by injecting cyst with 10% formalin & its removal within few (4-5) minutes. Praziquantel: effective in many cases. Albendazole, in high doses,: alternative. Control Avoid contact with infected dogs & cats and elimination of their.infection *if there is resistance for Praziquantal surgery removal of the cysts 19-Nov-15 NM Kaplan 29 Rx R to praziquantel; doses of Albendazole has some anti-parasitic.effect Surgery to remove the.cyst Control.Rodent control *intermediate host Rodents * problem with hydrated cysts ;they are multilocular "many chambers" Hymenolepis nana 19-Nov-15 NM Kaplan 30 most common cause of all cestode.infections Worldwide. In temperate areas its incidence is higher in children &.institutionalized groups.reservoir: Rodents.Infection is by oro-fecal route 19-Nov-15 NM Kaplan 31 12 P a g e
Adult worms cm, with small rounded scolex at 0.7X 1.5-4 Small.anterior end & proglottids at posterior wider end.weeks 6-4resides in ileal portion of small intestine for 19-Nov-15 NMKaplan 32 released from gravid proglottids through its genital atrium or when proglottids disintegrate in small intestine embryonated) (Mature immediately infective when. passed in stool days in 10>cannot survive. external environment Eggs round or slightly oval, smaller than those of H. diminuta, 40-60 X 30-50 µm. with striated outer shell & thin inner membrane. The space between membranes is smooth or faintly granular. two poles, on inner membrane, from w 4-8 polar filaments spread out between two membranes. Embryo (larva): Hexacanth oncosphere with six hooklets. NM Kaplan 33 *Blue color : what Dr read from the slide *Red color : most important points ** the most important diagnostic feature of these eggs two poles on inner membrane from 4-8 polar filaments spread out between two membranes Life cycle 1 Arthropod intermediate host( various spp of beetles & fleas ingestion of eggs cysticercoids (IS) )humans or rodents ingestion of arthropod adults in small intestine. 2 Direct ingestion of eggs)is( )NO intermediate host :w hatch oncospheres w penetrate intestinal villus cysticercoids larvae w, upon rupture of villus,return to intestinal lumen, evaginate their scoleces, attach to intestinal mucosa & develop into adults. * Cross human-to-human infection(infective cycle with passage through external environment) in contaminated food or water or from fecally-contaminated hands. * Human infection might be accidentally by "beetles & flea " Or direct by "eggs ingestion " * infective stage : cysicercoid Internal autoinfection(infective cycle without passage through environment) persistence of infection for years 13 P a g e external
:C/P Light infections vague abdominal. disturbances Heavier infections diarrhea, (enteritis abdominal cramping.)anorexia &.Dx: eggs in feces.doc: Praziquantel.Control: Hygiene H. diminuta NM Kaplan 35 Worldwide; cestode of rodents (frequently found in rodents) but infrequently seen in humans. Adults: 20-60 cm in length with slightly bigger eggs (with no polar filaments) & proglottids than H. nana. * you have to differentiate between H.nana & H.diminuta No-19 NM Kaplan 36 15v- Life cycle Dr Didn't read it 14 P a g e
Dipylidium caninum most common tapeworm infection in dogs & cats.in US :Adults Important slide NM Kaplan 38 Proglottids White, flat, amorphous &rice-like bodies in stool motile upon release into.environment small, can vary in size but longer than they are wide ccc barrel-shaped ( cucumber tapeworm) with genital pores 2 ccc dipylos = two gates) (.double-pored tapeworm Carmine-stain NM Kaplan 39 Egg s Embryonated & contain hexacanth oncosphere with 6 hooklets. round to oval (average 27-X 50-30 size.)µm48 often found in packets, eggs vs. eggs 15-5with. of many cestode spp *embryonated = mature =ready to infection *diagnostic feature : eggs found in pockets 15 P a g e NM Kaplan 40
Life cycle Infection of humans, most often children, by ingestion of infected intermediate host (flea or louse) infective larval stages attach to small intestine.adults C/P Rx 19-Nov-15 Light infections: DOC: praziquantel. NM Kaplan 41 often asymptomatic. Niclosamide is also effective. Heavier infections: non-specific symptoms as weight loss, abdominal pain, & failure to thrive. Control examination & Rx of household pets. aggressive flea abatement. You are smart enough to notice that clinical presentation is the same for all worms 19-Nov-15 NM Kaplan 42 Helpful Table 16 P a g e
Helpful Table Trematodes Flukes one by one, so it s important *Some Trematods have more than one name in different regions of the world Exa: S.hematobium &S.intercalatum *Dr:Important table and you need to know these differences ; these are general lines and you will be asked about them 17 P a g e
Schistosomes 1intermediate host snail (vs.other trematodes with 2 intermediate hosts) restricted geographical distribution 3 spp.: -1S.hematobium in Africa. (S.intercalatum in SE Asia) -2 S.mansoni in Africa & America. -3S.japonicum in far east (S.mekongi in central Africa) Various animals as dogs,cats,rodents,pigs,horses for S.japonicum,and dogs for S.mekongi. & goats, serve as reservoirs Adults reside in mesenteric venules in various locations.specific for each sp) in humans( vs. other hermaphroditic(separate sexes :)trematodes.mm long with slender shape 20-7 : * marginal long folds2 slightly smaller with : *.is held forming (Gynaecophoric canal) in w ccc eggs w often contain fully-developed.mature miracidium when excreted 19-Nov-15 NM Kaplan 48 & schistosomes NM Kaplan 18 P a g e 49
S. haematobium Adult Eggs in section of bladder NM Kaplan 50 S. haematobium; Eggs -110X 65-55(large µm( in urine with 170 terminal spine at.posterior end.dd: S. intercalatum TERMINAL SPINE NM Kaplan 51 S. Mansoni & Adult in copula & Adult 19 P a g e NM Kaplan 52
S. Mansoni; eggs 114-180 X 45-70 large ( µm( in feces, with lateral spine near posterior end. Anterior end is.tapered & slightly curved LATERAL SPINE NM Kaplan 53 S. japonicum & Adult in copula & Adult NM Kaplan 54 S. japonicum; eggs -70X 65-55(smaller µm(, typically 100 oval or subspherical, vestigial ( with knob. spine) on side.dd: S. mekongi NO SPINE 20 P a g e NM Kaplan 55
Life cycle bifurcated-tail Cercaria Most important diagnostic feature NM Kaplan 57 Pathology Adult worms are innocuous & coat themselves with host Ags to evade immune responses. Deposition of eggs granulomata & fibrotic lesions of liver, bladder or other organs malignant changes: Urinary; (S. haematobium): Haematuria, scarring, calcification, squamous cell carcinoma, occasional embolic egg granulomas in brain or spinal cord. Intestinal; (S. mansoni & S. japonicum): Katayama fever, hepatic perisinusoidal egg granulomas, Symmers pipe stem periportal fibrosis, portal hypertension & occasional embolic egg granulomas in brain or spinal cord. 21 P a g e 05/04/2013 NM Kaplan 58
)Katayama syndrome)katayama fever.s. japonicum &Esp. by S. mansoni weeks after initial 3 as early as (Acute exposure) egg-laying phase of schistosomiasis, a toxemic syndrome in heavy primary infections, rarely seen in. chronic cases form of immune complex disease or serum.sickness-like condition Schistosomiasis )Bilharziasis) 05/04/2013 NM Kaplan 59 250 million infected, 600 million at risk. Penetration of cercariae transient dermatitis (swimmers 'itch.( Symptoms are primarily due to reaction against deposited eggs In bladder :granulomatous lesions, hematuria & sometimes urethral occlusion. chronic infection in endemic areas most bladder cancers. In intestine: polyp formation w in severe cases dysentery. life threatening In liver :periportal fibrosis & portal hypertension HSM & ascites. Gross enlargement of esophageal & gastric veins (varices )rupture &hematemesis. S. japonicum eggs are sometimes carried to ) 1( CNS headache, disorientation, amnesia & coma ) 2( heart arteriolitis & fibrosis enlargement & Rt. ventricle failure Dx *ccc eggs Tests for viability of eggs* after Rx &Ova hatched in water motile miracidia seen by. hand-lens Eggs examined microscopically for ccc flickering movement flame of excretory. cells 22 P a g e Other serodiagnostic* tests.elisa for Ab detection.methods for Ag detection 05/04/2013 NM Kaplan 61
Generic Praziquantel DOC (effective.)against all spp.lack of toxicity.simple administration Rx Specific Metriphonate (organophosphate compound S.hematobium Oxamniquine S.mansoni 05/04/2013 NM Kaplan 62 Control Avoid contaminated water. sanitary disposal of sewage. destruction of snails. No vaccine is available. 19-Nov-15 NM Kaplan 63 Fasciolopsis buski (Giant intestinal fluke),adult; anterior end Adult carmine stain & endemic in central.southeast Asia.one year life span X 7.5-2elongate oval,.cm 2-0.8 Lives attached to small intestinal mucosa of mammalian hosts pigs) &humans ( & inflammation, ulceration cesses 5 s 1N a ov b - 19. NM Kaplan 64 23 P a g e
75-100 X 130-150 μm(. Immature eggs are discharged into intestine & passed in to mature & stool become embryonated in water. Eggs You need to memorize this slide *schistosome mature Buski immature. NM Kaplan 65 Life cycle Infection by ingesting water plants (water chestnuts) contaminated with encysted metacercaria w excyst in duodenum, attach to 30-25 intestinal mucosa & mature into adults in days eggs passed in feces & hatch in fresh water miracidia w must penetrate suitable snail intermediate host within hours & undergo several developmental stages (sporocysts, rediae & cercariae) cercaria released in fresh water & encyst as metacercariae on acquatic.vegetations 19-Nov-15 NM Kaplan 66 C/P Light infectons: &epigastric pain, nausea.diarrhea, esp. in morning Heavier infections: generalized edema &. ascites Dx.Eggs in faeces Rx.DOC: Praziquantel Control Avoid water chestnuts from contaminated.waters Sewage ttt before. disposal 24 P a g e NM Kaplan 67
Heterophyes heterophyes (Minute intestinal fluke) Adult Middle East, &Far East. infects &lives in small intestine of humans, various fish-eating mammals (e.g., cats & dogs) &birds. one of the smallest, 1.0-2.5 X 0.75-0.4mm. Adult stained with carmine oral sucker (OS), pharynx (PH), intestine (IN), ventral AC), & (sucker, or acetabulum.) eggs within uterus (UT NM Kaplan 68 Life cycle Infection by ingesting raw, undercooked or salted fish containing metacercariae w excyst, attach to mucosa of embryonated mature into adults & small intestine eggs (each with fully-developed miracidium) passed in feces, ingested by suitable snail (first intermediate host) & hatch miracidia released, penetrate snail s undergo several developmental stages (i.e. &intestine cercariae released cercariae) &sporocysts, rediae from snail & encyst as metacercariae in tissues of second intermediate (suitable fresh/brackish water fish.) host 19-Nov-15 NM Kaplan 69 C/P Intestinal main symptoms: diarrhea & colicky abdominal pain. Ectopic: eggs may penetrate small intestine mucosa, enter PB & migrate to extraintestinal sites as heart, liver, spinal cord & brain, where they can cause serious disease. 25 P a g e 19-Nov-15 NM Kaplan 70
Metagonimus yokogawai minute intestinal fluke Adult stained with carmine. - 1(smallest human fluke; oral sucker (OS), pharynx.).mm 0.4-0.3X 1.7 (PH), intestine (IN), genitoacetabulum (GA), ovary Mostly Far East, Siberia, (OV), large paired testes &Manchuria, Balkan states (TE), eggs within the uterus.spain (EG). Similar to H. heterophyes in. all aspects Metagonimus yokogawai ; another name for H.heterophys NM Kaplan 7 2 Liver flukes 26 P a g e
NM Kaplan 74 Fasciola hepatica )Sheep liver fluke(,adult: leaf.cm3 x1 shaped NM Kaplan 75 Eggs Embryonated eggs in µm, 150x 80 stool: indistinguishable from. those of F. buski NM Kaplan 76 27 P a g e
Life cycle Humans infection by ingesting raw or undercooked fresh water plants as watercress w harbor encysted larval metacercariae w excyst in duodenum, penetrate through intestinal wall, migrate to peritoneal cavity, penetrate liver capsule, wander through liver parenchyma for up to weeks & migrate into bile duct where it matures into 9 adult embryonated eggs in stool w hatch in water miracidia w penterate appropriate snail intermediate host & divide (sporocysts, redia & cercaria) cercariae w exit snail & encyst as metacercariae attached to acquatic. vegetations leaves 19-Nov-15 NM Kaplan 77 C/P Rx Praziquantel: NOT effective (vs. F. buski ),.Triclabendazole: effective NM Kaplan 79 28 P a g e
Past year Questions : "these are what I can reach to and collect from PYQ" Which of the following can cause a true infection as well as an infection in humans a. Hymenolepis diminuta b. Hymenolepis nana c. Taenia solium d. Dipylidium caninum Answer: b Which of the following statements is correct about trematodes: a. All trematodes need 2 intermediate hosts b. Adult Schistosomes do not usually cause the tissue damage caused by schistosomiasis. c. A treatment with can treat the n already happened Schistosomal dermatitis & Acute schistosomiasis Answer: b Which of the following statements is correct: a. Some nematodes can live freely in nature or as human parasites Forgive me For any mistake Many thanks for my best friend Aya Duais <3 Al-Anoud Al-Bustanji 29 P a g e