Presentation on theme: "P erinatal infections account for 2% - 3% of birth defects which arise form a spectrum of organisms & have varying modes of transmission. Not all birth."— Presentation transcript:
P erinatal infections account for 2% - 3% of birth defects which arise form a spectrum of organisms & have varying modes of transmission. Not all birth defects are routinely screened for during prenatal care, but all birth defects do pose a risk to the fetus or neonate. The variation in residual status of the mother after primary infection should be noticed. Caesarian section delivery is recommended only for mothers who have active genital lesions at the time of delivery.
mostly viral previously known as ( TORCH) infections: Toxoplasmosis, Other( syphilis), Rubella, CMV, Herpes( and Hepatitis), the first four are acquired antenately, herpes and hepatitis usually perinately. The term TORCH is now obsolete as other agents are important ( e.g. HIV). Most fetuses if infected during the first trimester will suffer from a syndrome of congenital malformation.
RUBELLA: ( German Measles). The fetus is most at risk in the first 16 weeks gestation. Causative Organism: Rubella virus ( togaviruses RNA). Route of Infection : via respiration as the virus is concentrated in the nasopharyngeal secretions. Incubation Period: days. Symptoms: Mild pyrexia, arthralgia, rash which persists for a week and always affecting the face, lymphadenopathy in the postauricular, deep cervical and suboccipital L.N. precedes the appearance of the rash and persists for 3 weeks. Risk of fetal transmission: % of fetuses are affected if maternal primary infection is in the first month of gestation. -22% in the second month, 6-10% in the third to fourth month.
Despite of availability of effective vaccines up to 20% of women of child bearing age don ’ t possess rubella antibody. Risk of Fetal infection % Risk of Fetal infection %
Routine antenatal screening: vaccination ( avoid pregnancy for 3 months). Maternal screening: routine rubella IgG in the first trimester, if infection suspected perform rubella IgM. Prevention: - vaccination before or after pregnancy ( not during). - in acute infection: droplet precautions. - in neonatal infection: contact precautions.
CYTOMEGALOVIRUS (CMV) in UK CMV is commoner cause of cong. Retardations than rubella. Infects 50%to 60% of women of childbearing age. Causative agent: CMV (Herpes virus DNA). Maternal symptoms : usually mild or asymptomatic, fever with/without lymphadenopathy, sore throat.
Transmission: direct: person to person contact ( saliva, milk, urine, semen, tears, stools, blood, cervical and vag. Secretion.). indirect: contaminated fomites. in primary CMV infection, 30-40% of fetuses will be infected, 2-4% of them will develop severe malformations at birth. in recurrent CMV infections ( about 1% of fetuses will be infected and the rest will appear normal at birth, but later in life, they may suffer from delayed speech and learning difficulties due to cerebral calcification and sensorineural hearing loss. And small group will have chorioretinitis.
Complications of fetal CMV infection include: 1. micro-& hydrocephaly 2. chorioretinitis 3. cerebral calcification 4. mental retardation 5. heart block 6. petechiae Maternal screening: not recommended. Prevention: hand washing( especially after changing diapers).
TOXOPLASMOSIS Causative agent: by protozoan toxoplasma gondi. Risk of fetal infection: First Trimester - 15 % ( less incidence of fetal infection but serious disease is most common ). Second Trimester - 25 %. Third Trimester - 65 % ( but almost 90% of newborns are without clinical signs of disease ). 40% of fetuses are affected if the mother has the illness. the earlier in pregnancy the more damage. Maternal symptoms: usually asymptomatic, fever, rash & eosinophelia If symptomatic ( the CNS prognosis is poor).
Maternal screening: not recommended, if infection suspected( toxoplasma IgG, IgM, and repeat test every 10 weeks through pregnancy. Treatment: start spiramycin in infected mothers to reduce transmission to the fetus. Prevention: wash hands before eating, after handling raw meat, after contact with cat feces, & soil & cook their meat adequately.
Infection in the pregnancy may result in: (occur only if there is acute exacerbation during pregnancy): 1.spontaneous abortion. 2.perinatal death. 3.abnormal growth. 4.characteristic triad of fetal anomalies: a- Chorioretinitis. b- Hydrocephaly or microcephaly. c- Cerebral calcification.
Human Immunodeficiency Virus (HIV) Causative agent: RNA retrovirus. Fetal transmission : is 25% if the mother is infected, reduced to 8% in if the mother is treated with zidovudine and less than 3% with suppressive triple antiretroviral therapy.
Transmission during pregnancy and Puerperium: majority of infants infected in third trimester or at time of delivery,vertical transmission can occur during vaginal delivery, so caesarean section is protective (up to 50%). premature babies are more at risk of vertical transmission. transmission may also occur with breastfeeding. bottle feeding reduces vertical transmission possibly by up to 50%.
Screening: Routine HIV antibody performed in 1st trimester). Repeat in 3rd trimester if high risk for HIV. Serology: IgG & IgM antibodies (false +ve in 1.6%). If HIV positive, consult Infectious Diseases,and avoid breastfeeding. transferred maternal antibody persists up to 18 months in uninfected infants, so gene amplification via polymerase chain reaction can detect neonatal HIV infection. intrauterine HIV is associated with prematurity and growth retardation.
Clinical problems :appear sooner in infected baby than in adult AIDS (e.g. at aged 6 month) with: - hepatosplenomegaly - failure to thrive - encephalopathy - recurrent fever - respiratory diseases (interstitial lymphocytic pneumonitis) - septicemia (salmonella) - pneumocystis - lymphadenopathy. Death is usually from respiratory failure or overwhelming infection( 20% at 18 months).
Most common cause of jaundice during pregnancy. HepatitisB transmitted by contaminated blood,saliva, breast milk, semen. VIRAL HIBATITIS
Hepatitis B DNA virus Complications: may cause Hepatitis,Cirrhosis and/or liver cancer (as an adult at age of years) · Rate of transmission from mother to fetus :10-20% (if HBeAg positive -90%) Pregnant women who are infected transmit the virus transplacentally to the fetus and at birth. Neonatal jaundice :is rare in women with chronic hepatitis or acquired hepatitis early in pregnancy. The risk is high when infection occurs late in pregnancy. Screening: Routine HBsAg (performed in 1st trimester). Prevention: HBIG (Hepatitis B immune globulin) and HBV vaccine should be given to baby at birth. If non-immune mother exposed in pregnancy give HBIG and HBV vaccine.
Hepatitis C RNA Virus Vertical transmission is low with rate of approximately 6%. The risk of transmission correlates with HCV viral titer in the mother. Complications: Hepatitis, Cirrhosis and/or liver cancer (as an adult). Screening: HCV-A B recommended in high risk pregnant patients: -intravenous drug users ( IVDU ). -blood transfusion before undiagnosed hepatitis. Prevention: Avoid high risk behavior, e.g. IVDU currently no post-exposure prophylaxis available.
Herpes Simplex (Primary or Recurrent). herpes virus family, DNA virus. Primary · Fetal loss · Congenital Syndrome Recurrent · Mucocutaneous lesions · Disseminated disease · Encephalitis Transmission occurs at time of delivery in % of cases( vaginal delivery). Neonatal HSV infection affects 1/5000 births (half of these related to primary infection). *Prevention:If lesions present at time of delivery, recommend caesarean section. - Daily oral acyclovir can be considered in late third trimester.
Varicella Zoster Herpes virus family, DNA virus. If infection occurs in first trimester 4.9% risk of congenital varicella. Congenital Syndrome -Limb hypoplasia -Ocular abnormalities -CNS abnormalities ( convulsive disorders ). -Dermatomal scarring
If infections aquired in the last 10 days of pregnancy result in variably sever fetal infections with neonatal mortality as high as 34%. Perinatal period (neonatal varicella) -Chicken pox -Encephalitis 20-40% risk of (neonatal varicella) infection if mother develops varicella in peripartum period.
Serology (IgG and IgM). Screening: Routine screening generally not recommended. Prevention: If pregnant woman (with no history of previous chickenpox) is exposed, perform STAT Varicella IgG. Exposed neonate should receive VZIG prophylaxis.
SYPHILIS Effect of Syphilis on Pregnancy: The more is the duration between infection and conception, the less is the foetal affection. Abortion: of a dead foetus after the 4th month of pregnancy when the spirochetes can cross the placenta as the cytotrophoblast starts to disappear. Repeated late abortions then premature or mature macerated still born then live born with congenital syphilis or developing it later on. congenital syphilis:-Skin eruption- osteititis of nasal bones – saddle nose – hepatosplenomegaly-frontal bossing -8 th nerve deafness.
Effect of Pregnancy on Syphilis Primary lesion which is the sign of early syphilis may be masked if infection occurs during pregnancy. Causative agent: Treponema Pallidum Mode of transmission: -sexual ( most common). -close contact with open lesions( rare). -direct blood transfusion. -cong. Syphilis Fetal infection is most likely when the mother is in the primary or secondary stages.
Diagnosis (A) History: of infection, repeated late abortions or macerated still birth. (B) Examination: Signs of primary, secondary or tertiary syphilis. (C) Investigations: by serological tests; (I) Non- specific (non-treponemal ) tests: Venereal disease research laboratory (VDRL). Rapid plasma reagin (RPR). (B) Specific (treponemal) tests: Fluorescent treponemal antibody absorption test (FTA - ABS). Treponema pallidum immobilization test (TPI). Non-treponemal test can be positive in other conditions as collagen diseases, lymphomas, mononucleosis, and febrile illnesses. So these tests can be performed as screening tests, if positive a specific (treponemal) test is done to confirm or refute syphilis.
Treatment (A) Mother: Treatment should be started before 16 weeks i.e. before spirochetes cross the placenta (I) Penicillin: Procaine penicillin units IM daily for 17 days or - benzathine penicillin (long acting) 2.4 million units IM, half the dose in each buttock. This is repeated for 3 courses at 2 weeks interval. (II) Erythromycin: 500 mg/ 6 hours orally for 21 days is given to patients who are allergic to penicillin. (B) New born: Procaine penicillin units IM for 10 days.
GONORRHEA Causative agent: Neisseria gonorrhoeae ( gram -ve diplococci). Symptoms: usually asymptomatic. Mucopurulent endocervical discharge, dysuria, proctitis. may cause perihepatitis ( Fitz -Hugh- Curtis syndrome). In infants: it infects conjunctiva (gonococcal ophthalmia neonatorum, prevented by 1% silver nitrate eye drops immediately after birth), pharynx, respiratory tract, or anal canal.
Diagnosis: gram stain of urethral or endocervical exudates ( intracellular diplococci). Culture. Treatment: in pregnancy: Ceftriaxone single i.m. dose.(Rocephine 1 gm I.v-I.m) Or Spectinomycin 2 gm single i.m. dose + erythromycin 500mg qds/7d. infants: Benzyl penicillin 30mg/kg stat. ( cephalosporin) + chloramphenicol eye drops.
CHLAMYDIA TRACHOMATIS Associated with: low birth weight, premature rupture of membrane, fetal death. Conjunctivitis in 5-14 days after birth. Complication: Chlamydia pneumonitis, pharyngitis,otitis media. Treatment: infant: 1% tetracycline oint, Or drops + erythromycin 10 mg/kg qds PO for 3 weeks. Parents: erythromycin PO During pregnancy: erythromycin is used, but Amoxicillin 500mg/8h PO for 1 week is better tolerated
Streptococcal infections Group A & B Beta-hemolytic Streptococci: Are the major causes of perinatal infection. Group B Streptococci which is a normal constituent of Genital tract in 5 to 25% of pregnant women has become the most common cause of perinatal infection. Diagnosis: St. infection is suspected in patients with primaturely ruptured membranes, septic abortion, endometirtis, chorioamnionitis, or pelvic peritonitis. The diagnosis is established by culturing group A or B St. from genital exudates or blood.
Life threatening: Puerperal infections occur on occasion in group B St. infections particularly in women with prolonged rupture of membranes, stillbirths & septic abortions are infrequent complication. 25% of infants: Born to mothers harboring Beta St. complicated with neonatal sepsis including meningitis & Pneumonia. Penicillin or ampicillin is Drug of choice.
Dr.Essam. S. Abushwereb Consultant Gynaecology & obstetrics 2010