Presentation on theme: "بسم الله الرحمن الرحيم Transplacental infections"— Presentation transcript:
1 بسم الله الرحمن الرحيم Transplacental infections ( Reproductive Block , Microbiology : 2016 )By: Dr.Malak El-Hazmi
2 OBJECTIVES; Toxoplasma , Treponema pallidum , Parvovirus , Types of infant infections.Major transplacentaly transmitted pathogens causing congenital infections .Toxoplasma ,Treponema pallidum ,Parvovirus ,Varicella Zoster Virus,Rubella virus ,Cytomegalovirus.Their major features & epidemiology .Manifestations of congenital infection.Diagnosis of congenital infection.Their Treatment and Prevention.
3 infant infections Classification Timing of events Mechanisms CongenitalIn uteroTrans placentalPerinatalDuring labour and deliveryExposure to genital secretions and bloodNeonatalAfter birthDirect contact,breast feeding ornosocomial exposure
4 Congenital infections mostly virusespreviously known as ( TORCH) infections:T= Toxoplasmosis,O=Others(syphilis ,Parvovirus &VZV),R=Rubella V,C=CMV,H=Herpes( Hepatitis &HIV),
5 Congenital infections Risk of IUI & fetal damage ;Type of org.(teratogenic)Type of maternal inf.(1o,R)Time of inf .(1st ,2nd or 3rd)1o Maternal infection in the first half of pregnancyposes the greatest risk to the fetus
6 Congenital infections Common FindingsIntrauterine growth retardation(IUGR)Hepatosplenomegaly(HSM)ThrombocytopeniaMicrocephalyMajority of CI (“asymptomatic”) at birthPreventative and therapeutic measures ;possible for some of the agents
7 Neonatal serological Dx; IgM antibody Persistence of specific IgG antibody >12 ms of ageAbsence of fetal IgM at birthdoes not exclude infection
9 Toxoplasma Gondii Oocysts; Obligate intracellular parasite Three forms:Oocysts;Bradyzoites:Tachyzoites:Immunity +Immunity -Shed in cat fecesrapidly dividing formsACUTE PHASEslowly dividing formsCHRONIC PHASE
10 Toxoplasma gondii, TRANSMISSION: Ingestion of oocyst: Contaminated fingers,soil,waterIngestion of cyst in undercooked meat.Blood transfusion and organ transplantTRANSMISSION:
11 Congenital infection ; TOXOCongenital infection ;Most cases, due to 10 maternal inf.Rarely, reactivation of a latent inf.
12 Congenital infection ; TOXOCongenital infection ;Most (70-90%) are asymptomatic at birthbut are still at high risk of developing abnormalities,especially eye (chorioretinitis )/neurologic disease(MR) later.Classic triad :Other signs include ;rash, HSM, jaundice, LAP, microcephaly, seizures, thrombocytopenia.Abortion & IUD.Intracranial calcificationsChorioretinitisHydrocephalus
13 Dx Infant *Prenatal Dx; Pregnant mother *Postnatal Dx; Serology; TOXO PCRCultureSerial U/S*Postnatal Dx;Serology;IgM, IgA,IgG or persistently +ve >12 msEvalution of infant(ex, neuroimaging)Pregnant motherSerology;IgM,IgGIgG avidityIgG seroconversioncompared to booking blood.
14 Rx Prevention Spiramycin. pyrimethamine& sulfadiazine. TOXO Avoid exposure to cat feces;Wash ;- hands with soap and water- fruits/vegetables,- surfaces that touchedfruits/vegetables/raw meat.Cook all meats thoroughly
16 Parvovirus B19 Worldwide distribution Humans are known hosts Parvoviridaenon developed V.Icosahedral capsid& s.s DNA genome.Epidemiology:Worldwide distributionHumans are known hostsTransmissionRespiratory routeTransplacental routeBlood transfusion
18 Congenital infection Inf in the 1st trimester IUD (Intrauterine death) ParvoCongenital infectionRisk of congenital infection is greatest when inf occur in 1st 20 wksInf in the 1st trimester IUD (Intrauterine death)Inf in the 2nd trimester HF(Hydrops fetalis)Inf in the 3rd trimester Lowest riskCause fetal loss through hydrops fetalis,severe anaemia,CHF, generalized oedema and fetal death
22 VZV infection in Pregnancy Primary infection is rare Why?Primary infection carries a greater risk of severe disease,in particular pneumoniaIntrauterine infectionscongenital varicella syndrome ;1st 20 weeks of PregnancyThe incidence of CVS is ~ 2%Scarring of skinHypoplasia of limbsCNS defectseye defectsNeonatal varicella ;< 5 days of delivery severe disease> 5 days before delivery mild disease
23 Diagnosis vzv Infant; Pregnant mother Direct ex: Prenatal Dx Vesicular fluid forvirus isolationCells scraping from the base of vesiclesImmunoFluorescent test (Ag)DNA-VZV by PCRSerological test:IgM AB*Infant;Prenatal DxVZV DNA in FB or AF or placenta villiVZV IgM in FB.U/SB. Postnatal DxVZV IgMvirus isolationVZVDNA in VFor CSF ( CNS INF )
24 Rx Prevention; vzv Acyclovir Pre exposure; live-attenuated vaccines. Post exposure;VZIGsusceptible pregnant women have been exposed to VZV.infants whose mothers develop V < 5 days of deliveryor the first 2 days after delivery.
28 Clinical manifestation: RVClinical manifestation:Acquired infection ;Ex. Maculopapular rash(German measles)Congenital infection;Normal CRS IUDRisk of acquiring congenital rubella infection varies and depends on gestational age of the fetus at the time of maternal infection.gestational age risk to fetus0-12 wks %13-16 wks %>16 wks Infrequent
36 Dx. Prenatal : Postnatal: Maternal : Serology ; CMV CMV IgM CMV IgG CMV IgG avidityPrenatal :PCR .cultureCMV specific IgMUltrasoundPostnatal:by isolating CMV or detection of its genomein first 3 wks of life.Body fluid : urine, saliva, blood.ByStandard tube culture methodShell vial assayPCRHistology;Detection of Cytomegalic InclusionBodies in affected tissueSerology; CMV IgMIntranuclear I B [Owl’s -eye]
37 Rx Prevention !? Symptomatic infants ? Ganciclovir . CMVRxSymptomatic infants ? Ganciclovir .Asymptomatic infants not recommended .Prevention !?Education about CMV& how to prevent itthrough hygiene;hand washingVaccine is not available(TRIAL)
39 OBJECTIVES; To recognize the different types of infant infections. Upon completion of this lecture, the students should be able toTo recognize the different types of infant infections.To know major transplacentaly transmitted pathogens causing congenital infections .(Toxoplasma , TP ,ParvoV , VZV, Rubella V & CMV.)To describe their structureTo know their major epidemiology featuresTo describe clinical manifestations of their congenital infectionsTo illustrate different laboratory diagnosis of maternal and congenital infectionTo know their treatment and preventive measures.