15. Congenital infections of the newborn. Flashcards
what are the three group of infections for newborn ?
INTRAUTERINE/ congenital infections - the signs and symptoms are present at birth
PERINATAL - infection can be acquired during birth and signs and symptoms present after birth and first 48hrs
POSTNATAL - signs and symptoms start 48 hrs after birth
what are the most common causative agents for intrauterine/ congenital infection
TORCH
t - toxoplasmosis O- other syphillus (trepanoma palladium , varicella zoster , parvovirus ) R - rubella C - cytomegalovirus H- herpes simplex virus
and congenital listeriosis
in which trimester is it most dangerous to acquire intrauterine infections ?
1st trimester - greater risk for fetus
especially because the infection with the mother can be asymptomatic
how can TORCH infections be avoided ?
immunisation of rubella and VZV before pregnancy or in childhood
and some infections such as syphilus treated with benzylpenicillin
what are the most common routes of intrauterine infections ?
hematologically - esp viruses
ascending infection from the vagina - bacteria and Herpes simplex virus type 2
what is the source of transmission in toxoplasma gondii ?
cat feces , raw or insufficiency cooked meat , unpasteurised milk
what are the clinical features in toxoplasmosis gondii ?
when the mother gets the infection in first trim
triad symptoms very severe
TRIAD:
chorioretinitis
DIFFUSE INTRACRANIAL calcifications
hydrocephalus / cerebral ventricular dilation
affected may die in utero or a few days after birth
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Term newborns usually present with a milder form of the disease with symptoms such as hepatosplenomegaly and lymphadenopathy.
no apparent clinical manifestations at birth OR
intellectual disability
Recurring chorioretinitis resulting in vision loss
Motor delays
Learning disorders
Intellectual disability
SENORINEURAL HEARING LOSS
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In comparison, preterm newborns exhibit severe symptoms
micro or macrocephaly
hydrocephalus
meningoencephalitis
nystagmus
petechia and purpura - blueberry muffin rash
lymphadenopathy
epilepsy / seizures
retinal scars
microphthalmia
retinochoroiditis
what is the diagnosis of toxoplasmosis ?
suggestive sonographic findings
fetus - amniocenteisis and do PCR
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for NEWBORN
CT or MRI - intracranial periventricular calcifications , hydrocephalus , ring enhancing lesions
IgM Toxoplasma specific antibodies (concern for false positives due to maternal contamination of fetal blood during labor, repeat serological testing should be done 10 days after birth ; half-life of Toxoplasma IgM and IgA antibodies is 5 and 10 days)
Negative IgM and IgA antibodies do not exclude the infection. If the mother is affected later in her pregnancy, there is a delay in the production of antibodies in the newborn. When an infection is suspected, the antibodies should be repeated every 2 to 4 weeks until at least 3 months of age
Positive IgG is indicative of prior or current maternal infection. In the presence of other suggestive features but negative IgM and IgA antibodies, toxoplasma IgG testing requires repetition every 4 to 6 weeks until complete disappearance
PCR for T gondii DNA
positive Toxoplasma IgM or Ig A antibodies in the CSF
ophthalmological evaluation
what is the treatmnet of congenital toxoplasmosis ?
mother 1st trimester - immediate spiramycin to prevent fetal toxoplasmosis
3grams a day
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after 18th week up to birth
pyrimethamine 100mg/day first two days and maintenance dose of 50mg/day
sulfadiazine - 75mg/kg/day
folinic acid - 15mg every 3 day
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newborn - pyrimethamine , sulfadiazine and folinic acid
12 months
pyrimethamine
For Neonate
1 mg/kg twice daily for 2 days, then 1 mg/kg once daily for 6 months,
then 1 mg/kg 3 times a week for 6 months
sulfadiazine
50 mg/kg twice daily for 12 months
Folinic acid (leucovorin): 10 mg, 3 times per week
higher doses and longer duration (2 years) are the recommended approach when the presentation is severe, with over three intracerebral calcifications and/or more than one ocular sign or severe abnormalities at birth.
Asymptomatic infants with positive serology or newborn screening receive treatment for 3 months. Some experts recommend adding steroids to this regimen when the CSF protein is high or severe chorioretinitis affecting vision. Steroid therapy continues until the disappearance of protein in CSF or resolution of chorioretinitis
prevention of toxoplasmosis gondii is very important to be to taught to mother what are the preventive methods ?
avoid raw undercooked meat
avoid contact with CAT LITTER
how is trepanoma palladium transmitted ?
sexual transmission
or perinatal transmission during birth
what are the clinical features of syphillus ?
inutero
miscarriage , stillbirth , hydrocephalic fetus
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neonates born with CS are asymptomatic at birth
early congenital syphilus usually appear by three months, <2years old onset
- hepatomegaly and jaundice
- rhinorrhea - Copious, persistent white discharge is noted, which contains spirochetes that can be visualized under darkfield microscopy.
maculopapular rash on palms and soles ,back, buttocks, posterior thigh
skeletal abnormalities
and generalised lymphadenopathy
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late congenital syphilus (onset >2 years of age)
saddle nose
frontal bossing
short maxilla
hutchinson teeth - hypoplastic notched and widely spaced teeth upper central incisors
SABER SHINS
sensorineural hearing loss
perioral fissures
Skin and mucous membrane gummas
cranial nerve palsy - nerve 8 causing deafness
Eye- interstitial keratitis
Intellectual disability
Sensorineural hearing loss
Hutchinson triad (Hutchinson teeth, interstitial keratitis, and sensorineural hearing loss)
what is the diagnosis for congenital syphillus ?
newborn and mother
Maternal screening for syphilis in early pregnancy important
All neonates born to mothers who have reactive nontreponemal and treponemal test results should be evaluated with a quantitative nontreponemal serologic test (RPR or VDRL) performed on the neonate’s serum!
because umbilical cord blood can become contaminated with maternal blood and yield a false-positive result,
and Wharton’s jelly within the umbilical cord can yield a false-negative result
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Non-treponemal tests
RPR -Rapid Plasma Reagin test
detects nonspecific anti-cardiolipin antibodies
is sensitive but not specific
or
VDRL Detects nonspecific anti-cardiolipin antibodies - is sensitive, but not specific
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Specific treponemal tests:
Conducting a treponemal test on neonatal serum is not recommended because it is difficult to interpret
Fluorescent treponemal antibody absorption (FTA-ABS) and/or micro hemagglutination test for antibodies to T.Pallidum (MHA-TP) testing
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CSF abnormalities including reactive CSF VDRL, CSF pleocytosis, elevated CSF protein
CSF PCR for detection of treponemal DNA
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Long bone radiographs that may show findings of pathologic fractures, metaphyseal serration, localized demineralization, and osseous destruction.
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always confirmatory test - dark field microscopy or PCR of suspicious lesion or bodily fluid (bullous rash and nasal discharge)
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in FETUS - repeated US examinations for plaentomegaly , hepatomegaly ascitis or hydrocephalus
what is the treatment for congenital syphilus ?
Infants up to 4 weeks of age: Aqueous crystalline penicillin G, 50,000 -75,000 units/kg intravenously every 12 hours in the first seven days of life. After 7 days of life, 50,000 units/kg per dose intravenously (IV) every 8 hours for 10 to 14 days. Alternatively, procaine penicillin G, 50,000 units/kg/day intramuscularly for 10 to 14 days.
Infants older than 4 weeks and older children: Aqueous penicillin G, 50,000 units/kg every 6 hours intravenously for 10 to 14 days.
how is listeria transmitted?
RAW milk products such as soft cheese -feta, brie, and camembert cheeses
or fish ,
meat
Do not eat refrigerated pâtés or meat spreads
or
direct contact with infected vaginal secretion or blood during delivery
what are the clinical features of listeria ?
Listeriosis of pregnancy :
- premature birth and spontaneous abortion
- Early-onset syndrome: granulomatosis infantiseptica - evere disseminated form of disease characterized by widespread microabscesses and granulomas
respiratory distress
Pustular erythematous lesion
fever
meningitis
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premature delivery with amnionitis
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Neonatal listeriosis
may be apparent within hours or days of birth (early onset) - frequentlylow birth weight, associated obstetric complications, show evidence of neonatal sepsis soon after birth with circulatory or respiratory insufficiency or both
Infants with late-onset listeriosis are generally full term, healthy at birth
source of listerial infection in this group is not known, but is possibly the mother’s alimentary tract or the environment, as the organism is rarely isolated from the mother’s genital tract
Late-onset syndrome (5 days to 3 weeks after birth): Listeria meningitis/encephalitis
