Varicella in Pregancy -Is it a teratogens ??

 

When to administer Intravenous acyclovir?? Any member have  ever had misfortune to prescribe I V acyclovir??  All about Varicella Zoster (Chicken Pox) / Shingles:  )

 Varicella: Prevalence in Pregnancy?  About 0.7% all pregnancies. May infect upto 2% of adults. Spread by droplets. Fortunately in childhood the disease is usually self limited. In elderly / immunocompromised men/ women reactivation of latent virus can occur.

1)         Maternal Treatment in pregnancy in uncomplicated cases?- Analgesics, calamine lotion, antipyretics, antipruritics, Oral acyclovir 800 mg 5 times per day to all pregnant women or Valacyclovir 1Gm TDS will be of help.

2)        Maternal Risks in pregnancy? May cause varicella pneumonia after primary C.  Pox infn, during preg particularly third trimester. Pneumonia appears 3-5 days after the appearance of rash. Maternal mortality due to such pneumonia may be as high as 35-40 %( specially in smokers) and warrants I V acyclovir   By contrast,  in nonpregnant state such rate will be less 11-17%. Such cases should be treated by acyclovir (DNA polymerase inhibitor). Pneumonia develops 2-5 days after fever, rash, and malaise. The drug of choice is acyclovir which is safe in pregnancy. Dose is 10-15 (some recommends lower dose of7.5) mg/Kg I.V. TDS× 8 days. If pneumonia develops shift her to ICU.

3)        What about  newborn if mother recently develops C Pox (5 days before or 2 days after birth)- a) administer varicella immune Globulin(VZIG) to neonate b) Delay the delivery if possible till the crusts disappear c) isolate the neonate from mother.

4)        Do we routinely enquire about varicella vaccine during preconception counseling? What an young adult women have to advise if she is unsure about childhood vaccination against varicella or cant remember whether she was ever affected with varicella?? My dear members make a habit of routine query in this regard  during Preconception counseling ? –In absence of definite clinical history of previous C Pox-?  If no prior history in childhood vaccine of C. Pox (VZV Vaccine- Varivax by Merck), then she is to susceptible infection. For adults two doses sub cut 6-8 weeks apart. But this live vaccine is contraindicated in pregnancy. Pregnancy may be allowed 3 months after vaccination. But there is no incidence of congenital VZV infection of foetus following vaccination in pregnancy.

5)        What to do if a pregnant woman is exposed to an infected case? How to prevent infection to persons who have already came in  close contact? A) If  the person who came in contact admit that she had had P/H/O C Pox- then no special Ry.   B) But if the person who came in contact  denies any past infection in childhood- Perform serology by 96 hrs of serology- .  In fact most preg women will be sero+ve for IgG against VZV. They are not at risk.

 If serology is negative or cannot be done then- I) then administer high titer VZIG-VariZIG (Varicella Zoster Immunoglobulin) intra muscularly.125 units/ per 10 kg body weight. Maximum dose 625 Units. If high titer immunoglobulin is not available in the market then go for I.V. Immunoglobulin at the dose of 400mg/Kg.

ii) Also allow oral acyclovir concurrently.  Prophylactically 800 mg 5 times daily.5-7 days. But this must be started within 9 days of therapy.

 

6)        Risk of Teratogens: Foetal Risks in pregnancy?  Spont abortion, IUFD, Varicella embryopathy- cutaneous scars, Limb hypoplasia, Muscle atrophy, malformed digits, MR, Microcephaly, cortical atrophy, Cataracts, Chorioretinitis. But the affection rate is low before 13 weeks to the rate of 0.4%.

7)        What are the vaccines that are safe in pregnancy??? Tet Vac, Hep B,

8)        What are the vaccines that are unsafe in pregnancy??? Varicella (live attenuated virus).

 

9)        Inadvertent immunization in preg- then what to do?-in a study of 52 cases who inadvertently received vacc in first trimester and continued the pregnancy no foetal abnormality was noted. But if infection occurs after 20 weeks- no Teratogens will occur. But better to do usg follow up have to rpt USG for polyhydramnios, Hydrops, echogenic foci within the abd organs, cardiac malformations, limb deformities, Microcephaly, FGR. Occasionally Skin Scar.