How to recognise a congenitally infected fetus? Dr. Amar Bhide Consultant in Obstetrics and Fetal Medicine

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1 How to recognise a congenitally infected fetus? Dr. Amar Bhide Consultant in Obstetrics and Fetal Medicine

2 Scope Cytomegalovirus Parvovirus Varicella Toxoplasma Rubella

3 Clinical scenarios Maternal exposure to infection or maternal infection Infection as a possible cause following scan findings Positive TORCH test result

4 Parvovirus Maternal exposure to infection or maternal infection Chicken-pox/Varicella Rubella CMV Toxoplasma

5 Parvo Virus FETAL ANAEMIA - HOW? PARVOVIRUS INFECTION Binding Immature Red Cells Aplastic Crisis

6 Maternal infection/exposure to Parvovirus Risk of fetal infection significant prior to 20 weeks, risk is 30-35% Determine maternal immunity If mother susceptible, weekly follow-up with ultrasound scans

7 PREDICTION OF ANAEMIA Doppler - Blood Flow Velocity Flow Velocities Increased in all vessels Middle Cerebral Artery Brain responds --Hypoxia Easy visualisation 0-deg Insonation Good Reproducibility

8 Parvovirus Anaemia Anaemia - Hyperdynamic Circulation

9 PREDICTION OF ANAEMIA Parvovirus Sensitivity Specificity Cosmi,

10 Maternal Varicella exposure/infection Determine maternal immune status Consider maternal Immunoglobulin therapy Fetal effect is thought to be due to re-activation of the virus Congenital Varicella syndrome has been described Abortion Chorio-retinitis Cataracts Limb atrophy Cerebral cortical atrophy Neurological disability

11 Maternal Varicella infection 347 women with primary Varicella Zoster infection were described Only one case of congenital Varicella syndrome (retinal macular lesion and skin scars) One case each of fetal death and hydrops was seen 17 and 20 weeks after first trimester maternal infection at 11 and 5 weeks respectively Harger et al, Obstet & Gynecol 2002;100:262

12 Maternal Varicella infection Ultrasound scan at least 5 weeks after maternal infection Limb deformity, microcephaly, hydrocephalus, softtissue calcification and intrauterine growth restriction can be detected VZV DNA has a high sensitivity but a low specificity for the development of Fetal Varicella Syndrome 13 cases of FVS seen following1423 women with chickenpox before 20 weeks of gestation (0.91%) RCOG Green-top guideline No.13, 2007

13 Rubella (German measles) Uncommon, as rubella vaccination provides lifelong immunity Source for primary infection uncommon in the UK All our cases had travelled overseas in pregnancy Highly infective virus Congenital rubella syndrome characterized by: intrauterine growth restriction intracranial calcifications, microcephaly cataracts cardiac defects (PDA or pulmonary arterial hypoplasia) neurologic disease (with a broad range of presentations, from behaviour disorders to meningo-encephalitis) hepatosplenomegaly

14 Toxoplasma infection Referral from Ophthalmology following diagnosis of chorioretinits Pet (cat) ownership

15 Risk factors for congenital toxoplasmosis Risk factor Have kittens Odds ratio 3 or more v/s v/s Eat rare lamb 8.4 Eat raw ground beef 6.7 Drink unpasteurised Goat s milk 5.1 Jones et al, Clinical Infectious Diseases 2009; 49:878 84

16 Clinical scenarios Maternal exposure to infection or maternal infection Infection as a possible cause following scan findings Positive result of a routinely performed TORCH test

17 Infection as a possible cause following scan findings Hydrops fetalis/cardiomegaly Ventriculomegaly Small fetus/fetal growth restriction Bright bowel, Calcifications

18 Looking for fetal infection with ultrasound abnormality

19 CONGENITAL INFECTIONS HYDROPS CARDIAC FAILURE Anaemia Myocarditis HEPATIC FAILURE Hypoproteinaemia Portal hypertension Parvovirus B19 Coxsackie Toxoplasmosis CMV

20 Cardiomegaly

21 HYDROPS FETALIS

22 CONGENITAL INFECTIONS Cranial Abnormalities Ventriculomegaly Intracranial calcification Microcephaly

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25 CONGENITAL INFECTIONS ECHOGENIC BOWEL LIVER ECHOGENICITIES ISCHAEMIA INFLAMMATORY REACTION THICKENED MECONIUM

26 CONGENITAL INFECTIONS Echogenic Bowel/ Liver Densities

27 Echogenic Bowel/ Liver Densities

28 Echogenic Bowel/ Liver Densities

29 CONGENITAL INFECTIONS INTRA-UTERINE GROWTH RESTRICTION Early Onset Low / absent Liquor Umb/Fetal Dopplers Placental insufficiency

30 CONGENITAL INFECTIONS Intra-Uterine Growth Restriction HC FL AC

31 Normal Uterine Doppler Oligo/anhydramnios

32 Clinical scenarios Maternal exposure to infection or maternal infection Infection as a possible cause following scan findings Positive result of a routinely performed TORCH test

33 Positive TORCH result Performing a TORCH test without a clear indication is generally a bad idea Test detects antibodies, but is unable to distinguish between a recent and a past infection Majority of positive test results are as a result of past infection (which usually indicates immunity) Approximately 50% pregnant women are immune for CMV, 5-15% for Toxoplasma, 60% for Parvovirus, over 95% for Rubella, and 90% for Chicken-pox (Varicella).

34 Diagnostic steps Mother susceptible? Confirm maternal infection/seroconversion Identify fetal infection Assess impact of fetal infection

35 Toxoplasma 89 cases of fetal Toxoplasma infection were described in 1270 women with Toxoplasma infection in pregnancy(7%) 34 TOPs were performed due to ultrasound findings IUGR and microcephaly were not observed 55 infants were born alive, and 54/55 were normal at follow-up at 6 mths to 4 years. Hohlfeld et al, UOG 1:241, 1991

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38 Congenital CMV infection

39 Congenital CMV infection 73 fetuses infected with CMV were studied retrospectively A poor outcome was observed in 35 cases Predictors of poor outcome were the following: Cerebral ultrasound abnormality (OR 25.5) Non-cerebral ultrasound abnormality (OR 7.2) Low platelets (OR 1.24 for every 10,000/cu mm decrease) Benoist et al, BJOG 115:823, 2008

40 CONGENITAL INFECTIONS PROGNOSIS WORSE IN THE PRESENCE OF U/S FEATURES Infection Not Affect

41 Diagnostic steps Mother susceptible? Confirm maternal infection/seroconversion Identify fetal infection Assess impact of fetal infection

42 Clear communication is important

43 Clear communication is important

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45 Thank you