Presentation on theme: "Infections in the Newborn and beyond"— Presentation transcript:
1 Infections in the Newborn and beyond Tony RyanUniversity College Cork
2 Objectives The common means of transmission of these infections. The major manifestations of congenital and perinatal infections.Diagnose and prevent these infections.Some picturesThe infectious diseases Lucky Box
3 Infection in the Newborn Overall < 1%NICU 16%VLBW (<2500 g) 30%Mortality 30%
9 Clinical Features maculopapular rash lymphadenopathy fever arthropathy (up to 60% of cases)
10 Rubella History 1881 Rubella accepted as a distinct disease 1941 Associated with congenital disease (Gregg)1961 Rubella virus first isolated1967 Serological tests available1969 Rubella vaccines available
11 Risks of rubella infection during pregnancy Preconception minimal risk0-12 weeks 100% risk of fetus being congenitally infected Spontaneous abortion occurs in 20% of cases.13-16 weeks deafness and retinopathy 15%after 16 weeks normal development, slight risk of deafness and retinopathy
12 Outcome Congenital Rubella 1/3 rd will lead normal independent lives1/3 rd will live with parents1/3rd will be institutionalised
13 Prevention Antenatal screening Non-immune women vaccinated post partum Effective live attenuated vaccine (95% efficacy)Universal vaccination (MMR)Selectively vaccination of schoolgirls
15 Congential CMV Herpes virus Large DNA virus Characteristics Infection H simplex (i/ii), Varicella, EBV, HHV 6,7,8Large DNA virusinclusion bodiesCharacteristicslatencyreactivationInfectionprimary, recurrent, reactivation
16 Cytomegalovirus member of the herpesvirus primary infection usually asymptomatic. Virus then becomes latent and is reactivated from time to time.transmitted by infected saliva, breast milk, sexually and through infected blood60% of the population eventually become infected. In some developing countries, the figure is up to 95%.
17 Congenital InfectionIsolation of CMV from the saliva or urine within 3 weeks of birth.Commonest congenital viral infection, affects % of all live births.The second most common cause of mental disibility after Down's syndromeTransmission to the fetus may occur following primary or recurrent CMV infection. 40% chance of transmission to the fetus following a primary infection.
18 Cytomegalic Inclusion Disease CNS abnormalities- microcephaly, mental retardation, spasticity, epilepsy,periventricular calcification.Eye - choroidoretinitis and optic atrophyEar - sensorineural deafnessLiver - hepatosplenomegaly and jaundice which is due to hepatitis.Lung - pneumonitisHeart - myocarditisThrombocytopenic purpura, Haemolytic anaemiaLate sequelae in individuals asymptomatic at birthhearing defects and reduced intelligence.
19 Diagnosis Isolation of CMV from the urine or saliva of the neonate. Presence of CMV IgM from the blood of the neonate.Detection of Cytomegalic Inclusion Bodies from affected tissue (rarely used)
20 Management Of Congenital CMV Primary Infection - termination of pregnancy?40% chance of the fetus being infected.10% chance that congenitally infected baby will be symptomatic at birth or develop sequelae later in life.4% chance (1 in 25) of giving birth to an infant with CMV problems.Recurrent Infection - termination not recommended as risk of transmission to the fetus is much lower.Antenatal Screening – impractical.Vaccination - may become available in the near future.
25 ParvovirusCausative agent of Fifth disease (erythema infectiosum), clinically difficult to distinguish from rubella.Also causes aplastic crisis in individuals with haemolytic anaemias as erythrocyte progenitors are targeted.Spread by the respiratory route, 60-70% of the population is eventually infected.50% of women of childbearing age are susceptible to infection.
26 Congenital Parvovirus Infection Known to cause fetal losshydrops fetalis; severe anaemia, congestive heart failure, generalized oedema and fetal deathNo evidence of teratogenecity.Risk of fetal death highest in second trimester (12%).Minimal risk to the fetus in first or third trimestersMaternal infection during pregnancy does not warrant termination of pregnancy.Cases of diagnosed hydrops fetalis had been successfully treated in utero by intrauterine transfusions
41 Neonatal VaricellaVZV can cross the placenta in the late stages of pregnancyNeonatal varicella may vary from a mild disease to a fatal disseminated infection.If rash in mother occurs more than 1 week before delivery, then sufficient immunity would have been transferred to the fetus.Zoster immunoglobulin should be given to susceptible pregnant women who had contact with suspected cases of varicella.Zoster immunoglobulin should also be given to infants whose mothers develop varicella during the last 7 days of pregnancy or the first 14 days after delivery.
50 Summary CMV 1% newborns infected (0.2% - 2.5%) 90% asymptomatic Higher infection rate with primary maternal (50%) than after recurrent maternal (1%)Urine culture (gold standard)worse outcome withretinitis, microcephaly, neurological findingsPrevention is better than cure!
51 Features of the Host Portals of entry Host immunity (skin, cord, cannulae)Host immunity(poor local inflammatory response)Antibiotic exposure(superinfection, yeasts)Prematurity(immune-deficient, sicker)
56 Characteristics of Rubella RNA enveloped virus, member of the togavirus familySpread by respiratory droplets.In the prevaccination era, 80% of women were already infected by childbearing age.
57 Infection increased by certain features of microorganisms PathogenicityGBS, CONS, E.Coli, etc.Doseheavy colonization increases infectionCompetitione.g. inhibition of yeasts by bacteria
58 Laboratory Diagnosis Diagnosis of acute infection Rising titres of antibody (mainly IgG)Presence of rubella-specific IgM -
59 Typical Serological Events following acute rubella infection level
60 Neonatal Herpes Simplex (1) Incidence of neonatal HSV infection varies inexplicably from country to country e.g. from 1 in 4000 live births in the U.S. to 1 in live births in the UK.The baby is usually infected perinatally during passage through the birth canal.Premature rupturing of the membranes is a well recognized risk factor.The risk of perinatal transmission is greatest when there is a florid primary infection in the mother.There is an appreciably smaller risk from recurrent lesions in the mother, probably because of the lower viral load and the presence of specific antibody.The baby may also be infected from other sources such as oral lesions from the mother or a herpetic whitlow in a nurse.
61 Neonatal Herpes Simplex (2) The spectrum of neonatal HSV infection varies from a mild disease localized to the skin to a fatal disseminated infection.Infection is particularly dangerous in premature infants.Where dissemination occurs, the organs most commonly involved are the liver, adrenals and the brain.Where the brain is involved, the prognosis is particularly severe. The encephalitis is global and of such severity that the brain may be liquefied.A large proportion of survivors of neonatal HSV infection have residual disabilities.Acyclovir should be promptly given in all suspected cases of neonatal HSV infection.The only means of prevention is to offer caesarean section to mothers with florid genital HSV lesions.
62 Varicella-Zoster Virus 90% of pregnant women already immune, therefore primary infection is rare during pregnancyPrimary infection during pregnancy carries a greater risk of severe disease, in particular pneumoniaFirst 20 weeks of Pregnancyup to 3% chance of transmission to the fetus,recognised congenital varicella syndrome;Scarring of skinHypoplasia of limbsCNS and eye defectsDeath in infancy normal
66 Epidemiology of CMV Shed Transfer body secretions, urine Intimate contacttransplacentalduring birthbreast feedingblood productsorgan transplantation
67 CMV in the newborn 1% newborns infected (0.2% - 2.5%) Higher infection rate with primary maternal (50%) than after recurrent maternal (1%)50% of babies fed CMV infected breast milk get infection
68 CMV in Toddlers Day care Can shed for up to a year Plastic toys Hands of day care workers
69 CMV in Pregnancy 90% of women asymptomatic Primary infection 1 - 4% of pregnanciesFoetal transmission % (~ 40%)More neuro sequelae in infants of primary infectionMaternal antibody does not protect against infection but may be associated with less sequelae
70 Diagnosis in Pregnancy Usually asymptomaticSometimes ‘flu-like illness (like EBV)Conversion to IgG positiveRising titres not helpful
71 CMV and foetus Transmission can occur in all trimesters Adverse neuro outcome more likely in 1st trimester infectionOligohydramniospolyhydramniosIUGRnon-immune hydropsasciteseffusionsMicrocephalydilated ventriclescalcificationpseudomeconium ileus
72 Diagnosis in foetus Remember most foetuses look normal Ultrasound findingsCMV IgM (sensitivity = 75%)negative result does not exclude infectionAmniocentesis/cordocentesisculture/PCRLFTs, thrombocytopenia, leucopeniaAntenatal counseling difficult
73 CMV and newborn 90% newborn asymptomatic 10% have clinical signs SGA microcephalycalcificationchorioretinitishearing losshepatosplenomegalyjaundicePetechiaethrombocytopeniameningitis
74 Lab diagnosis in newborn Urine culture (gold standard)positive in first 3 weeks suggests congenitalCMV IgM (sensitivity = 75%)negative result does not exclude infectionCMV PCR (urine)LFT’s, thrombocytopenia, anaemia, leucopenia
75 Long term Follow-up essential “When the rockets go upWho cares where they come downThat’s not my departmentSays Werner von Braun”
76 CMV in older children/adolescents Intrafamilialsexual contactblood productsDay care workersSocioeconomicdeveloping countries (80% of 3 year olds; 100% of adults)UK/USA upper SE class 40-60%; lower SE class 80%
77 Prevention of CMV Vaccine Focus on high-risk (childbearing) Education CMV negative blood
78 Follow up Neuro-developmental Opthalmology Hearing (BAER) Educational dyspraxialearning difficulties
79 Better outcome Worse outcome Reticulo-endothelial involvement When CNS not involvedWorse outcomeChorio-RetinitisMicrocephalyEarly neurological findings
80 ‘Silent’ CMV outcomeHearing loss 15%mostly normal neurologically
81 Infectious diseases (U.S.) pre vaccination and 1997