pregnant INVESTIGATION OF RUBELLA IN PREGNANT WOMEN OF

(pregnant)

INVESTIGATION OF RUBELLA IN PREGNANT WOMEN OF UNKNOWN RUBELLA IMMUNITY STATUS S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 2

Rubella & Pregnancy Rubella is the first virus demonstrated as a teratogen. Humans are the only natural host of rubella virus(EXCLUSIVELY) S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 3

Rubella in Pregnant Women What happened when a pregnant woman exposed to RUELLA? S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 4

Rubella in Pregnant Women When a pregnant woman is exposed to rubella What should we do? S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 5

Gregg´s congenital rubella syndrome Gregg was the first to describe the 3 characteristic manifestations of CRS: -heart disease -cataracts -deafness S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 6

”Gregg´s children” at school in 1948 S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 7

Rubella in Pregnant Women Why? Maternal Infection Maternal viremia Intrauterine Transmission CRS S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 8

Rubella in Pregnant Women The most important determinant of fetal infection & fetal defects is: GESTATIONAL AGE S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 9

Rubella in Pregnant Women When will a pregnant mother get VIREMIA ? Maternal immunization : - vaccine-related - Previous Infection Re-infection: 2%, especially <12 wk, CRS(rare) Lit. Review: 30 Re- infection in adults and children S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 10

Rubella in Pregnant Women What happened for mother when she exposed to RUELLA? Immunity(+) “ (-): -nothing -Infection -subclinical, symptomatic S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 11

RUBELLA: The incubation period : 14– 21 days The prodromal phase : mild catarrhal symptoms 2/3 of infections: subclinical The most characteristic sign is retroauricular, posterior cervical, and postoccipital lymphadenopathy (No other disease causes the tender enlargement of these nodes) An enanthem appears in 20% of patients just before the onset of the skin rash. It consists of discrete rose-colored spots on the soft palate (Forchheimer spots) Lymphadenopathy is evident at least 24 hr before the rash appears and may remain for 1 wk or more. RASH: It begins on the face and spreads quickly. Its evolution is so rapid that the rash may be fading on the face by the time it appears on the trunk. During the second day the rash may assume a pinpoint appearance, especially over the trunk, resembling that of scarlet fever. Mild itching may occur. The eruption usually clears by the third day. Desquamation is minimal. Rubella without a rash has been described. S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 12

Clinical Features maculopapular rash lymphadenopathy fever arthropathy (up to 60% of cases) S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 13

Consequences of CRI during pregnancy : Maternal rubella during pregnancy can result in: -miscarriage, -fetal death, -congenital rubella syndrome -Late sequels years later -placental infection ± persistent fetal infection -no infection(counseling? ) S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 14

Rubella in Pregnant Women The most important thing is: GESTATIONAL AGE Fetal Inf. (Miller & colleagues) 90% <11 wk G. A 67% 13 -14 25% 23 -26 53% Third trimester 100%(last month of pregnancy) Congenital defect: 90% if maternal infection < 11 wk (<8 wk, first month) 33% 11 -12 wk 11% 13 -14 24% 15 -16 Uncommn >16 S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 15

Rubella in Pregnant Women Why this happen? The placenta is a relatively effective barrier to fetal infection from 12 -28 wk but it is not so effective in the first & third trimesters Particularly in the last month of pregnancy S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 16

Pathogenesis: Cellular & tissue damage in the infected fetus: -Tissue necrosis due to vascular insufficiency -Reduced cellular multiplication time -Chromosomal breaks -Production of a protein inhibitor causing mitotic arrests in certain cell types S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 17

Rubella in Pregnant Women The most distnctive feature of congenital rubella is: CHRONICITY ONCE THE FETUS IS INFECTED EARLY IN GESTATION The virus persists in fetal tissue until well beyond delivery S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 18

Rubella in Pregnant Women CRS is not a static disease ¾ of infected infants show NO apparent involvement at birth but experience consequences years later Sonography (NL? ) conselling S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 19

Rubella in Pregnant Women Recommendation: all rashes in pregnancy be investigated S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 20

S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 21

Rubella in Pregnant Women 1 -A blood specimen should be obtained as soon as possible for specific Ig. G and Ig. M antibody 2 -A single positive Ig. G test indicates rubella immunity 3 -A significant rise in Ig. G Ab (paired sera) or positive Ig. M Ab test indicates recent infection 4 -Negative Ig. G and negative Ig. M on first testing should be retested (the first specimen should be reanalyzed along with the second specimen ) 5 -Positive Ig. G titers and negative Ig. M to determine if they acquired immunity before pregnancy or infection during pregnancy S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 22

Typical Serological Events following acute rubella infection Note that in reinfection, Ig. M is usually absent or only present transiently at a low level S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 23

How to Counsel this pregnant women ? 1 - IG 2 - VACCINE 3 - Termination of pregnancy 4 - NOTHING S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 24

IG (immune globulin) No recommendation for routine use in pregnant women 0. 55 mg/kg IG (IM): 1 - ↓ viral shedding 2 - ↓ Rate of the viremia Points: 1 -The absence of clinical signs in a woman who has received IM-IG does not guarantee that fetal infection has been prevented 2 -Adminstration of IG eliminates the value of Ig. G-Ab testing to detect maternal infection but Ig. M-Ab can be used. S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 25

Rubella vaccine: Immunizatoin of non-pregnant women within 3 days of exposure Because if the exposure did no result In infection, immunization will protect them in the future. Pregnancy within 28 days (3 months) of immunization The MMR vaccine must be offered to Ig. G negative women postpartum S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 26

Rubella vaccine (cont. ) BUT in pregnant women: A small % of offspring in such acses had signs of infection, but no defects. Rubella vaccine during pregnancy ≠ termination S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 27

Children of pregnant women: Shed small amount of virus from the pharynx (7 -28 days after immunization) NO evidence of transmission of the vaccine virus NO Risk for mother S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 28

TERMINATION The only effective way to prevent CRS is to terminate the pregnancy But it is not an easy decision Why? Evaluation of mother/baby S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 29

Prevention (1) Since 1968, a highly effective live attenuated vaccine has been available with 95% efficacy Universal vaccination is now offered to all infants as part of the MMR regimen Some countries continue to selectively vaccinate schoolgirls before they reach childbearing age. Both universal and selective vaccination policies will work provided that the coverage is high enough. S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 30

Prevention (2) Antenatal screening: All pregnant women attending antenatal clinics are tested for immune status against rubella. Non-immune women are offered rubella vaccination in the immediate post partum period. S. R. Tabatabaei MD, MPH - PIRC 11/27/2007 31