Infections in children Flashcards
What infections can be acquired in utero?
Viruses: CMV, parvovirus B19, rubella, HIV, HBV, VZV
Bacteria: listeria monocytogenes, treponema pallidum, mycobacterium tuberculosis
Protozoa: toxoplasma gondii
Name some intrapartum infections
Bacteria: group B streptococcus, E.coli, pseudomonas spp, serratia spp, salmonella, neisseria gonorrhoea, chlamydia trachomatis
Viruses: HIV, HSV1, HSV2, HBV, HCV
Name some postpartum infections
Bacteria: coagulase-negative staphylococci, S.aureus, strep pneumoniae, E.coli, klebsiella pneumoniae, salmonella serratia, pseudomonas aeruginosa, enterococci, group B streptococci
Viruses: CMV, RSV, influenza, parainfluenza 1-4, enterovirus, parechovirus, adenovirus, rhinovirus, human metapneumovirus, bocavirus
Fungi: candida
How can congenital infections be transmitted?
passed from mother to baby in 2 ways:
- through the placenta before the baby is born
- during the passage through the birth canal (perinatal infection)
Mechanisms to transmit congenital infections
sexual intercourse with infected male partner
via placenta during viraemia or bacteraemia
shedding of virus in genital tract
ascending infection during premature rupture of membranes
use of invasive techniques eg. scalp electrodes
What are the TORCH infections?
Toxoplasma gondii
Other (treponema pallidum, parvovirus B19)
Rubella
Cytomegalovirus
Herpes simplex
What is meant by TORCH infections?
a group of diseases that can be passed from a mother to her fetus during pregnancy or childbirth
How is CMV transmitted?
contact with saliva or urine of young children is a major cause of CMV infection in pregnant women
other modes of transmission = sex, milk/breastfeeding
Temporary symptoms caused by congenital (present at birth) CMV infection
liver problems + large liver
spleen problems + large spleen
jaundice
purple skin splotches
lung problems
small size at birth
seizures
Permanent symptoms/disabilities caused by congenital CMV infection
hearing loss
vision loss
mental disability
small head
lack of coordination
seizures
death
When should you consider investigations for congenital CMV infection?
newborn screening programme identifies deafness/hearing impairment in newborn babies - if no response to 2 hearing tests saliva swab is tested for CMV DNA by PCR
detectable CMV DNA will trigger MRI, USS and eye examinations
What hearing tests are done on newborns?
automated otoacoustic emission (AOAE) test
no response –> automated auditory brainstem response (AABR) test
Features of congenital toxoplasma infection
chorioretinitis
hydrocephalus from aqueductal stenosis
intracranial calcification
other features = rash, lymphadenopathy, hepatomegaly, splenomegaly, jaundice, thrombocytopaenia
How is toxoplasma infection diagnosed?
test collection of paired cord blood or neonatal sample and a maternal specimen
PCR in blood or CSF
Toxoplasma infection treatment
spiramycin or pyrimethamine-sulfadiazine
Layers of meninges
dura mater
arachnoid mater
pia mater
What is bacterial meningitis?
invasion of bacteria into the sterile environment of the blood, followed by infiltration of the meninges, causing meningeal inflammation
Cause of meningococcal meningitis
neisseria meningitidis
gram-negative diplococcus
different serotypes (A, B, C, Y, W135)
Clinical presentation of meningococcal meningitis
sudden onset
vomiting
irritability
neck stiffness
headache
high fever
photophobia
decreased LOC
seizures
petechial or purpuric rash
Complications of meningitis
hearing loss
brain damage
learning disability
loss of limbs
Rash in meningococcal meningitis
non-blanching petechial or purpuric rash
evolves from initial blanching maculopapular rash
severe cases = large ecchymotic areas develop (purpura fulminans) which involve haemorrhage and necrosis of skin
Commonest cause of death in meningitis
raised ICP
Raised ICP features
reduced LOC
relative bradycardia
hypertension
focal neurological signs
abnormal posturing
unequal, dilated or poorly responsive pupils
papilloedema
Meningococcal meningitis features
clinical presentation (neck stiffness, rash, photophobia etc)
CSF microscopy/culture, blood culture
PCR (blood or CSF)
