Infections in Pregnancy

1. Infections in Pregnancy Dr Shahnaz Aram

2. General Principles Pregnancy does not alter resistance to infection Severe infections have greater effects on the fetus Maternal antibodies cross the placenta and give passive immunity to the fetus Fetus becomes immunologically competent from the 14th week

3. Fetus and Infection • Indirect effect - O2transport, nutrient exchange • Direct effect - invasion of placenta and infection of fetus • Viruses more than bacteria • rarely effect fetus unless maternal infection is severe • exception: Rubella, CMV, Herpes Simplex

4. Fetus and Infection Infections cause - miscarriage - congenital anomalies - fetal hydrops - fetal death - preterm delivery - preterm rupture of the membranes

5. Viral Diseases • Rubella • Parvovirus • Cytomegalovirus • Varicella Zoster • Herpes • Hepatitis • HIV • Rubeola

6. Measles (Rubeola) • Paramyxovirus • Incubation - 10-14 days • Respiratory droplet inoculation • Fever, rash, cough, rhinorrhea, conjunctivitis and Koplik’s spots • Pneumonia (2nd bacterial) main cause of death • Encephalomyolitis, SSPE, Hepatitis

7. Measles (Rubeola) • No increased maternal or fetal deaths • Risk of preterm delivery • No specific syndrome • Neonatal measles and pneumonia if active disease in mother • Increased PNM in developing countries

8. Measles (Rubeola) • Prevention vaccine (95% recipients protected) • Treatment antipyrexials cough suppresants Antibiotics for bacteria Suppress uterine contractions ? Immune serum globulin • Isolation precautions

9. Rubella • Togavirus (RNA virus) • Incubation - 14-21 days • Respiratory droplet inoculation • only modestly contagious • Fever, rash (3 days), cough, arthralgias, post auricular and suboccipital lymphadenopathy • Usually mild, overt clinical symptoms 50-75% of cases • Encephalitis, bleeding diathesis & arthritis are rare complications

10. Rubella and the Fetus • Purpura, Splenomegaly, jaundice, meningoencephalitis, thrombocytopenia are transient • Congenital cataracts, Glaucoma, heart disease, deafness, microcephaly and mental retardation are permanent abnormalities • Diabetes, thyroid abnormalities, precocious puberty & Progressive panencephalitis (late)

11. Rubella • Vaccination (95% seroconversion) @ 15 months and early adulthood • Immune status checking in teenagers, pre-college and pre-pregnancy • Antenatal testing • Serology testing for presumed exposures (paired Sera) • No in-utero therapy

12. Parvovirus • Human parvovirus B19 (DNA virus) - erythema infectiosum in childhood - chronic arthropathy - chronic bone marrow failure (immunodefic) - aplastic crisis (Sickle disaease) • Incubation 4-14 days • Respiratory droplet spread • High fever, “Slapped cheek syndrome’ non specific rash, no symptoms

13. Parvovirus and fetus • Hydrops (anaemia, myocarditis) • Adults 60% sero-positive • 1/3 fetuses affected in acute infection • Fetal loss rare with appropriate treatment • Assess serology - IgG, IgM, paired serology • Serial ultrasound, intrauterine transfusion

14. Varicella • Varicella-Zoster virus (DNA) • Incubation - 10-20 days • Respiratory droplet inoculation • Fever, malaise, pruritic rash (maculopapular with vesicles) • Pneumonia (+/- bacterial), encephalitis, myocarditis, pericarditis and adrenal insufficiency especially in adults

15. Varicella and pregnancy • Mild immunocompromise of pregnancy increases risk • 10% develop pulmonary complications - main cause of mortality • Fetal effects Preterm delivery Varicella syndrome Neonatal varicella (VZ first 2 months)

16. Varicella Syndrome Cutaneous scarring Limb hypoplasia Missing/hypoplastic digits Limb paralysis/muscle atrophy Psychomotor retardation Convulsions Microcephaly Cerebral atrophy Chorioretinitis/ chorioretinal scarring/optic disc hypoplasia Cataracts Horner’s Syndrome Early childhood Zoster

17. Cytomegalovirus • DNA virus • Congenital infection - 1% • 5-10% of those infected show clinical illness at birth • Neonatal MR - 20-30% • 90% of survivors get late complications • 5-15% with no demonstrable disease at birth get some abnormality (deafness)

18. CMV Congenital Infection • Hepatomegaly } • Spleenomegaly } • Jaundice }TORCH • Thrombocytopenia }Syndrome • Petechiae } • Microcephaly } • Intrauterine growth retardation }

19. CMV Congenital Infection (Late) • Venticulomegaly • Cerebral atrophy • Mental retardation • Psychomotor delay • Seizures • Learning difficulties and language delay • Chorioretinitis / Optic atrophy • Intracranial calcifications • Long bone radiolucencies, dental abnormalities • Pneumonitis

20. CMV Congenital Infection • Prolonged virus shedding • No vaccine • No treatment • Risk group advice

21. Herpes Simplex • Disseminated disease in pregnant woman - death from hepatitis, encephalitis • Miscarriage (severe disease) • No congenital syndrome known • Intrapartum infection • disseminated disease - chorioretinitis, meningitis, encephalitis, mental retardation, seizures and death • Primary infection >>>secondary infection • HSV II - 75%; HSV I - 25% cases

22. Hepatitis B • Intrauterine infection - 5% • Intrapartum infection - 95% • Congenital infection - 90% chronic carriers • About 1% mothers are potential risks for their newborns • Newborns should receive passive (HBIg) and active immunization (vaccine x 3 doses) - protective in over 90% of cases

23. Hepatitis C • Risk of transmission to fetus 6-30% • Increased if other infections such as HIV • No treatment • Value of C Section is uncertain • Avoid invasive procedures

24. HIV • Infection rates variable • Risk of vertical transmission 20-40%, mostly peri-partum • Screening and treatment can almost completely reduce vertical transmission • C Section reduces risk of transmission x 4-fold • Viral counts <1000 - negligible risk to fetus

25. Bacterial Infections • Bacteruria* • Vaginal infections (BV, TV, Candida) • Group B Streptococci* • Gonorrhoea* • Chlamydia* • Toxoplasmosis* • Listeria

26. Bacteruria • Asymptomatic • 5-8% of all pregnancies (2% Non-preg) • Urinary stasis, tract dilatation • 30% symptomatic UTI (Pyelonephritis) • Diagnosis • Treatment • Subsequent care (MSU v Prophylaxis)

27. Group B Streptococci • 25% women are carriers • 50% of babies born will be colonized • 1-2% will have Grp B Strep infection • 1:1000 babies • Pneumonia (early), Meninigitis (Late) • Screening v Risk factor prophylaxis

28. Gonorrhoea • Neissseria Gonorrhoea (1-6% pop) • Pre-term labour, PPROM, Chorioamniionitis, Endometritis • Gonococcal opthalmia neonatorum (40%) • 80% asymptomatic • Screening needed? • Cephtriaxone IM stat

29. Chlamydia • 5-7% reproductive population • Pre-term labour, PPROM, Chorioamniionitis, Endometritis • Conjunctivitis (18-50%), Pneumonia (18%) • Most are asymptomatic • Screening needed • Azithromycin 1 gram stat

30. Syphilis • T.Pallidum • <1:1000 pregnant women • Can infect trans placenta from 15th week • Second stage by birth if not treated • Screening – VDRL, RPR • Diagnostic tests – TPI, FTA-Abs • High dose Penicillin's

31. Toxoplasmosis • Toxoplasma Gondii (Protozoa) • Cat faeces, raw/undercooked meats • TORCH syndrome • Chorioretinitis, Encephalitis, Neonatal Jaundice • Serology =/- PCR • Sulfonamides + Pyrimethamine

32. Intra-Amniotic Infection • 1-2% all deliveries • Clinical Diagnosis – fever, uterine tenderness, Leucocytosis • Histologic chorioamnionitis more common • Ascending infection, rarely haematogenous • Polymicrobial • Increased PTD, PNMR, C Palsy, Endometritis • Treatment – Antibiotics and delivery

33. Miscellaneous • Malaria • Mycoplasma • HPV • Tropical diseases