Infections in pregnancy.txt

  1. infections in pregnancy
  2. what are the 3 ways infections can be transmitted from mother to child?
    • in utero: transplacentally
    • intrapartum: during birth
    • neonatal period: post partum - breast feeding
  3. what are 2 ways of prenatal diagnosis of congenital infection and the risk of fettle death with each?
    • amniocentesis: 1%
    • percutaneous umbilical cord sampling: 1-2%
  4. what are the 4 congenital viral infections?
    • rubella
    • parvovirus B19
    • VZV
    • CMV
    • (remember the first 2 go together and the last 2 are herpesviruses)
  5. which 7 infections can be acquired during birth? split into 2 categoris
    • BBV: HIV, Hep B, Hep C, HTLV
    • local infection genital tract: HSV, HPV, VZV
  6. which 4 tests are done as routine antenatal testing at booking for infections?
    • rubella IgG: check immunity (should have IgG)
    • HIV Ab/Ag test
    • Hep B: look for sAg
    • syphilis
  7. what is the risk to the fetes with maternal rubella infection and when is this a problem?
    • first trimester infection
    • congenital rubella triad: cardiac, ophthalmic, auditory
  8. what is the congenital rubella triad?
    • cardiac: patent ductus arteriosus
    • ophthalmic: cataracts
    • auditory: sensorineural deafness
  9. what are the 2 mechanisms of pathogenesis of fetal damage in rubella infection?
    • virus induced tissue damage
    • virus induced retardation of cell division
  10. how do you diagnose maternal rubella infection?
    rubella IgM, IgG
  11. how do you diagnose fettle rubella infection ie pre natal?
    • cord blood
    • rubella IgM
    • nucleic acid test
  12. how do you diagnose rubella infection in neonate?
  13. how does the damage on the fetes differ according to trimester?
    • 1st trimester: severely damaged, congenital rubella triad
    • 11-20 weeks: deafness only
    • after 20 weeks: no documented fettle damage
  14. how do you manage rubella infection in pregnancy?
    no anti viral drug
  15. how to prevent rubella infection?
    universal childhood immunisation: MMR
  16. which other disease has a similar presentation to rubella?
    • parvovirus B19
    • so always check blood for both
  17. what are the other names for parvovirus B19 infection?
    • slapped cheek disease
    • fifth disease
    • erythema infectiouum
  18. what is the main risk to fetes in parvovirus B19 infection? and when is this risk important?
    • 1st 20/40 weeks
    • hydrops fetalis: oedema in >2 compartments
    • fettle loss/ intrauterine death
    • highest in 2nd trimester
  19. why do you get hydrous fettles in parvovirus B19
    • due to severe anaemia due to infection and lysis of erythroid progenitor cells due to B19
    • fetal viral myocarditis
    • the anaemia causes heart failure and so get oedema
  20. what are the 2 important causes of anaemia in fetes?
    • parvovirus B19
    • rhesus disease of the newborn
  21. how do you make diagnosis of B19 in mother?
    B19 IgM and IgG seroconversion
  22. how do you diagnose B19 in fetes?
    • parvovirus DNA detected by dot blot and PCR (B19 NAT)
    • check fettle Hb for anaemia
  23. how do you treat B19 infection?
    • no specific antiviral
    • serial US scan to detect hydrops (see ascites, pulm oedema..)
    • intrauterine fettle blood transfusion if severe anaemia
  24. what is the most common congenital infection?
  25. what are the features of CID? (top to toe all systems)
    • cytomegalic inclusion disease
    • skin: petechiae (due to thrombocytopenia)
    • head: microcephaly
    • brain: seizures
    • eyes: choroidoretinitis
    • lungs: pneumonitis
    • abdo: jaundice, hepatosplenomegaly
    • overall size: small for gestation
  26. what 3 things do you find in blood tests for CID?
    • 1. low platelets
    • 2. high transaminase
    • 3. high conjugated biliruin
  27. what is the prognosis like in CID?
    • poor
    • mortality 20-30%
  28. what are the major sequalae of CID?
    • neuro
    • mental retardation
    • spastic diplegia
  29. what % of women of childbearing age are CMV seropositive?
  30. what are signs of primary infection?
    • asymptomatic
    • glandular fever like
  31. how is CMV transmitted?
    • transplacentally
    • during birth
    • via breastfeeding
  32. during which part of pregnancy can CMV infection cause fettle damage? and what is transmission rate? what does this depend on?
    • throughout pregnancy
    • 40% transmission rate
    • if it is mothers PRIMARY INFECTION
  33. what % of neonates with Congeintal CMV infection get severe symptoms?
    • 7% get CID
    • 14% are asymptomatic at birth but later get hearing defects and impaired intellectual performance
  34. how is diagnosis of maternal CMV infection made?
    Ab seroconverion and IgM (ie was IgG -ve now IgG+)
  35. how is CMV diagnosed in fetes?
    • abnormal fetus
    • quantify CMV NA in amniotic fluid as CMV is shed in urine
  36. how do you make post natal diagnosis of CMV?
    CMV in urine of newborn
  37. how is Congenital CMV managed?
    • in pregnancy discuss prognosis (bad)
    • no safe antiviral
    • however gangiclovir if CNS disease and will stop deafness but TOXIC!
  38. what is the main worry to mother about getting chickenpox in pregnancy?
    • more serious
    • pneumonitis
  39. what are consequences to fetes of maternal varicella? and when in preg?
    • fetal varicella syndrome in 1st and 2nd trimester
    • LENS
    • lymb hypoplasia
    • eye defects
    • neuro abnormalities
    • skin scarring in a dermatomal distribution
  40. what is risk of varicella in 2nd/3rd trimester?
    ZOSTER ie shingles in infancy as low immune system
  41. what is risk of varicella around delivery?
    • risk of neonatal varicella which is severe chickenpox
    • risk of pneumonitis
  42. what is the risk of zoster in pregnancy to fetes?
    • no risk to fetes
    • unless mother is immunosuppressed or shingles is disseminated
  43. how do you diagnose chickenpox in mothers and post natal babies?
    • clinical: typical rash
    • culture: EM, VZV NAT (remember no antibodies)
  44. how do you diagnose chickenpox in fetes?
    • ultrasound examintion
    • VZV NAT in amniotic fluid?
  45. if a mother has chickenpox or shingles in pregnancy how to treat?
    aciclovir safe in pregnancy
  46. if mother has contact with someone else with shingles or chickenpox then how to treat, what does it depend on?
    • depends if had chickenpox in past
    • give VZIg for susceptible within 10 days of contact
  47. how do you treat maternal chickenpox at birth?
    VZIg for neonate
  48. what must all HCW have had if haven't had chickenpox before?
    VZV vaccination
  49. which 2 bacterial agents are important congenital/neonatal infections?
    • GBS
    • listeriosis
  50. what is GBS normal flora of?
    • GI tract
    • 30% intermittent vaginal colonisation
  51. what are the 2 forms of neonatal infection with GBS?
    • early
    • late
  52. what defines early onset GBS infection?
    within 48 hours of birth
  53. what is the clinical feature of early GBS infection?
  54. how is early onset GBS acquired?
    passage through colonised birth canal
  55. what are risk factors for early onset GBS?
    • prematurity as fragile skin, poor immune system
    • prolonged ROM as baby has easy access to bacteria in birth canal
    • maternal pyrexia indicated more virulent strain and mum hasn't made Ab so none passed to baby
    • previous infected baby
    • documented GBS during pregnancy: should give prophylaxis
  56. what is difference in mortality between early and late onset GBS infection?
    • early has high mortality
    • 10% overall
    • late has only 5% mortality
  57. what defines late onset GBS infection?
    > 1 week after birth
  58. what is the clinical feature of late GBS infection?
  59. how is late GBS transmitted?
    • from genital tract
    • transmitted by CARERS post nattily
  60. what are the 2 risk factors for late onset GBS infection?
    • prematurity
    • procedures/manipulation
  61. what are the long term effects of late onset GBS?
    • longterm neurological sequalae
    • learning difficulties
    • hearing loss
  62. how is GBS diagnosed?
    culture of blood urine CSF surface swabs
  63. what is management of GBS infection?
  64. if a mother has risk factors for GBS infection, what is done to prevent GBS in neonate?
    • intrapartum antibiotics: amoxicillin or if pen allergic clindamycin
    • monitor baby for sepsis
    • strict infection control on SCBU, NICU
  65. what is treatment to baby with GBS?
    iv penicillin and gentamicin
  66. what is the name of the GBS organism?
    streptococcus agalactiae
  67. which group of strep is GBS?
    B haemolytic group B strep
  68. which organism causes listeriosis?
    listeria monocytogenes
  69. where is listeria found?
    unpasturised animal produce eg pate, soft cheeses
  70. what temp does listeria multiply at?
    refrigeration temperatures
  71. what are risks to fetes of maternal listeria if transplacental infection?
    • fettle death
    • prematurity
    • septicaemia
  72. what are risks to fetes if intrapartum infection?
    • septicaemia or meningitis
    • within 2 weeks
  73. what is mortality of listeria infection in neonate?
  74. how is listeria diagnosed in mother?
    blood cultures
  75. how is listeria diagnosed in neonate?
    • CSF, meconium, blood, urine
    • placenta
  76. what does placenta of listeria infection look like?
    moth eaten due to micro abscesses
  77. what is treatment of listeria infection?
    iv amoxicillin 3 weeks and gentamicin 1 week
  78. how to prevent listeria infection in mothers?
    • dietary regulation
    • avoid aborted animal foetuses ie female farmers and farmers wives be careful!
  79. what is the infectious eye problem worry about in neonates?
    • ophthalmia neonatorum
    • infectious neonatal conjunctivitis
  80. what are organisms that cause ophthalmia neonatorum?
    • N gonorrhoea: G-ve diplococci
    • C trachomatis
    • S aureus
    • S pneumo
  81. when and how does gonococcal ophthalmia neonatorum present?
    • within 5 days of birth
    • purulent discharge
  82. how do you diagnose GC ophthalmia neonatorum?
    microscopy and culture of eye swab
  83. what is treatment of GC ophthalmia neonatorum?
    systemic benzylpenicillin OR cefotaxime
  84. when does chlamydial ophthalmia neonatorum present and how?
    • 6-21 days after birth
    • mucopurulent discharge, watery bloody discharge
  85. how is chlamydial ophthalmia neonatorum diagnosed?
    NAAT on eye swab
  86. what is treatment for chlamydial ophthalmia neonatorum?
    systemic erythromycin and topical tetracycline
  87. who else must be treated in ophthalmia neonatorum?
    parents (STD)
  88. what 2 diseases can chlamydia trachoma's cause in neonates?
    • conjunctivitis
    • pneumonitis
  89. why is chlamydial pneumonitis underdiagnosed? what are symptoms and treatment?
    • mild symptoms
    • dyspnoea and staccato cough
    • Rx: erythromycin
  90. what is long term risk of pneumonitis?
    30% develop asthma
  91. what is name of organism for congenital toxoplasmosis?
    toxoplasma gondii
  92. which animal is toxoplasma assoc with?
  93. what kind of organism is toxoplamsa?
    protozoan parasite
  94. what is mode of transmission for toxoplasma to fetes? and how does that affect fettle infection and damage?
    • transplacentally
    • 1st T: low infection, high damage
    • 2nd T: 50:50
    • 3rd T: high infection as large placenta but little damage
  95. what are main consequences to fetes in congenital toxoplasmosis?
    • abortion or still birth
    • if live birth: classical triad of: intracranial calcification, hydrocephalus, choroidoretinitis
  96. what are the more common signs of congenital toxopl?
    • encephalitis
    • epilepsy
    • mental and growth retardation
    • jaundice
    • hepatoplenomegaly
    • thrombocytopenia
    • rash
  97. which organ is most affected by congen toxopl?
    EYES - choroidoretinitis can even be picked up later in life
  98. how is toxoplasma infection diagnosed in mother?
    • infection often asymptomatic
    • serology but IgM can stay positive for 3 years!
    • rely on combo of IgG, IgM, IgA and AVIDITY
  99. which special serological test do you do in toxoplasmosis?
    • avidity ie how avid is the Ab being that brings to toxoplasma
    • high avidity means infection was >6/12 ago
    • low avidity: RECENT infection
  100. how is fettle infection with toxoplasma diagnosed?
    • imaging see damage
    • PCR on amniotic fluid
    • post natal serology until 12 months
  101. what are 2 options of treatment for congenital toxoplasmosis?
    • termination
    • treatment during pregnancy: sulphadiazine/pyrimethamine/folinic acid alternating with spiramycin
    • neonate: sulphadiazine/pyrimethamine/folinic acid for 1 year
  102. what is important to FU in toxoplasmos infection?
  103. what advice do you give to prevent toxoplasmosis?
    • avoid undercooked meats and uncooked vegetables
    • avoid cat litter!
  104. what is the transmission rate if a mother has early untreated syphilis?
  105. how is transmission of syphilis during pregnancy reduced?
    treat syphilis!
  106. what are signs of early congenital syphilis?
    • signs of secondary syphilis
    • skin: condylomata lata, rashes
    • skeletal: osteochondritis, periostitis
    • organs: hepatosplenomeg, GN, CNS, eye
    • blood: haemolysis, low plt
  107. what are late manifestations of congenital syphilis?
    • interstitial keratitis: cloudy cornea
    • hutchinson's teeth: notched incisors
    • clutters joints: large malformed as inflamed
    • gummatous involvement
  108. what is the ANC screening test for syphilis?
    • EIA (specific for treponema)
    • if EIA positive then do TPPA, RPR, IgM
  109. what is antenatal management of penicillin?
    • im procaine penicillin for 10 das
    • or 1 dose benzathine penicillin im stat
  110. what tests are done to neonates to screen for syphilis?
    • serology IgM
    • darkfield microscopy of skin lesions
    • repeat serology up to 1 year
  111. how is infected neonate managed?
    iv or im penicillin for 10 days
  112. 2 day old neonate born after premature ROM is febrile and has convulsions, what is differential for organism?
    • GBS
    • E Coli
    • listeria
  113. which 2 Ix do for febrile convulsions
    • blood culture
    • CSF
  114. what Rx start?
    • ben pen and gent
    • add amox if suspect listeria
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Infections in pregnancy.txt
infec preg