logging in or signing up wuchereria NEW kumudha10 Download Post to : URL : Related Presentations : Let's Connect Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Copy embed code: Embed: Flash iPad Dynamic Copy Does not support media & animations Automatically changes to Flash or non-Flash embed WordPress Embed Customize Embed URL: Copy Thumbnail: Copy The presentation is successfully added In Your Favorites. Views: 1219 Category: Science & Tech.. License: All Rights Reserved Like it (0) Dislike it (0) Added: February 25, 2011 This Presentation is Public Favorites: 1 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript Wuchereria: Wuchereria Dr.K.S.Kumudha Valli I yr P.G. MD Microbiology Madras Medical college Rajiv Gandhi GGH, Chennai – 3.Slide 2: Class Nematoda Order Spirurida Superfamily Filarioidea Genera: Wuchereria, Brugia, Onchocerca, Loa, Drofilaria, Mansonella. Adults live in tissues or body cavities of vertebrate host. Females produce microfilariae that circulate through the host. Undergo development in, and are transmitted by arthropod vectors.Nematoda Characteristics: Nematoda Characteristics Elongated, Cylindrical, unsegmented bodies Body covered with tough cuticle. Diecious Complete alimentary tract. Sexual reproduction .Wuchereria bancrofti (Bancroft’s filaria) : Wuchereria bancrofti (Bancroft’s filaria) Adult worms- Lymphatic vessels & lymph nodes Have preference for: Testicular tissue, Lymphatic glands of groin, labia and Mammary glands of femalesEpidemiology : Epidemiology Man is only known host Found in the tropics India West Indies Puerto rico Southern China Japan South America Microfilariae -Morphology : Microfilariae -Morphology Long, hair like, transparent Filiform shaped Male : 2.5-4 cms x 0.1mm , 2 spicules at tail end Female : 8-10 cms x 0.2-0.3 mm, narrow, pointed tail viviparous (gives birth to larvae ) Life span:5-10 yrs Colorless, blunt heads and pointed tailsSlide 8: Embryo - 290 µm x 6-7µm *Hyaline sheath *Cuticle *Somatic cells or nuclei * # Nerve ring # Ant. V spot-represents rudimentary excretory system # Post. V spot-represents terminal part of alimentary canal *G (Genital) cells 1,2,3 &4-posterior *Innenkorper of Fulleborn or Central (Internal) body of Manson-spot-represents rudimentary alimentary canalLife cycle: Life cycle 2 hosts- man & mosquito Infective form- 3 rd stage larva POE- skin Def. host: man Microfilariae are produced 6-8months after infection with L3 larvae 5-18 months-sexually mature Intermed. Host: mosquito – Culex, Aedes & Anopheles 14 th day infective to man Microfilariae unsheath in mosquito gut, migrate to thoracic muscles, undergo two molts becoming L3 larvae in 10 to 11days.(Do not divide in vector – cyclodevelopmental biological transmissionSlide 11: 6-8months after infection with L3 larvae 5-18 months-sexually mature undergo two molts becoming L3 larvae in 10 to 11daysPeriodicity: Microfilariae circulation in blood is periodic. Periodicity is characteristic of species (strain) and geographic area. Nocturnal Periodicity- microfilariae in blood are high during 10 pm – 4 am In most regions W. bancrofti exhibit nocturnal periodicity – Culex fatigans . In South Pacific they exhibit diurnal periodicity – Aedes polynensis ( subperiodic). PeriodicityPathogenesis : Pathogenesis Attributable to adult worms Mostly asymptomatic in early years Low grade fever -immune reaction to developing worms. Acute phase of infection -when microfilariae are released. Host responds to dying worms and worm byproducts. Lymph nodes become inflamed. Immune cell activation leads to fevers, chills toxemia …Slide 15: Lymphatic vessels become swollen, damaged and leaky (lymphedema). leakage of protein or fluid to surrounding tissues. Can have localized swellings in arms and legs. In males scrotum usually affected. Lymphangitis Lymphatic obstruction Lymph varix ElephantiasisClinical manifestations: Clinical manifestations Asymptomatic Symptomatic Inflammatory Lymphangitis & lymphadenitis Obstructive Varicose LN, scrotum, hydrocele, chyluria, elephantiasisOccult filariasis (Meyers- Kouwenaar syndrome): Occult filariasis (Meyers- Kouwenaar syndrome) Massive eosinophilia Gen. lymphnode enlargement Hepatosplenomegaly Pulmonary symptoms Absence of microfilaremia Unusual host-reaction to filarial antigen, mf destroyed in tissues High titre of filarial- complement fixing antibody Clinical, haematological & serological manifestations respond readily to DECTropical pulmonary eosinophilia ( Eosinophilic lung, Weingarten’s syndrome): Tropical pulmonary eosinophilia ( Eosinophilic lung, Weingarten’s syndrome) Fever, Wt loss Paroxysmal cough Dyspnoea Splenomegaly CXR-miliary mottling in lung fields Demonstration of mf in Lung biopsyPathogenic lesions: Pathogenic lesions Inflammation Dilatation of lymphatics-Lymphangiovarix Rupture of Lymphangiovarix Lymphorrhagia Chylorrhagia Hyperplasia of skin & conn. Tissue- Elephantiasis Secondary bacterial infectionLymphangitis: Lymphangitis Epididymo-orchitis Funiculitis (spermatic cord) Retroperitoneal lymphangitis Lymphatics of upper & lower extremitiesSlide 22: Lymphadenitis Inflammation of regional LN Not painful, skin not adherent Filarial fever-3-5 days Hydrocele Chyluria Rupture of varicose chyle vessels thro. Mucus memb of urinary tractElephantiasis: Fibrotic constriction of afferent lymphatics Development of secondary channels. More lymph flows into tissue. Eventually calcification and blockade. Found in a small proportion of infected individuals. Often seen after prolonged exposure. ElephantiasisDiagnosis and treatment: Diagnosis and treatment Direct evidence Search for Microfilariae In peripheral blood Chylous urine Exudate of lymph varix Hydrocele fluid Search for Adult worms Bx lymph node Calcified worm in X raySlide 25: Indirect evidence Allergic tests Blood exmn-eosinophilia Intradermal test Immunological tests CFTSlide 26: Samples should be collected at night Use of thick blood smears stained with hematoxylin or Giemsa. Mf not found in blood in: Elephantiasis, due to lymph obstruction After lymphangitis, due to death of adult worm During early allergic manifestation Occult filariasisSlide 28: Xenodiagnosis Demonstration of Mf in stomach blood of Mosquito after biting infected ptTreatment: Treatment Filaricidal On Adult worms : Mel.W( Arsenical preparation) On Mf : DEC ( Hetrazan) On Infective larvae and Immature Adult worms : para-Melaninyl phenyl stibonate (MSb)Prevention:: Prevention: Destruction of mosquitos Reducing the rate of infection among insect vectors Treatment of carriers by using Hetrazan Protection against mosquito bitesOTHERS: OTHERS BRUGIA MALAYI: Seen in natives of sumatra. Distribution restricted. In India more in Kerela. BRUGIA TIMORI: Limited to timor. Mf larger than Mf malayi. Fails to take giemsa stain. Leison – development of draining abscesses by worms in lymph nodes----- scarring.Distingushing features of Mf.bancrofti&Mf.malayi: Distingushing features of Mf.bancrofti&Mf.malayi FEATURES Mf.bancrofti Mf.malayi Length 250 to 300µm 175 to 230µm Appearance Graceful,sweeping curves Kinky ,with secondary curves Cephalic space Length and breadth equal Almost twice as long as broad Stylet at anterior end Single Double Excretory pore Not prominent Prominent Nuclear column Discrete nuclei Blurred Tail tip Pointed ,free of nuclei Two distinct nuclei,one at tip,other subterminal Sheath Faintly stained Well stainedMf.bancrofti Mf.malayi: Mf.bancrofti Mf.malayiSlide 34: Thankyou You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.