MI: Neonatal and Childhood Infections Pt.1 Flashcards
Which infections are screened for in pregnancy?
- HIV
- Hepatitis B
- Syphilis
Which other congenital infections are known to cause issues in pregnancy/delivery?
- TORCH
- Toxoplasmosis
- Other (varicella, parvovirus)
- Rubella
- CMV
- Herpes
- Group B Streptococcus
- Hepatitis C
What is the source of toxoplasmosis?
Cat faeces
What are the possible outcomes for neonates with congenital toxoplasmosis?
Asymptomatic (60%) at birth but go on to develop long-term sequelae such as deafness, low IQ and microcephaly
Symptomatic (40%) at birth
- Triad
- Chorioretinitis
- Hydrocephalus
- Intracranial calcifications
- Other features: seizures, hepatosplenomegaly/jaundice
What is the triad of features in congenital rubella syndrome?
- Cataracts
- Congenital heart disease (PDA is most common)
- Sensorineuronal deafness
- Other features: microphthalmia, glaucoma, retinopathy, ASD/VSD, microcephaly, meningoencephalopathy, developmental delay
How is herpes simplex virus transmitted to the neonate? What are the presenting features?
- In utero/congenital - rare (5%)
- Triad of cutaneous, ophthalmic, and CNS manifestations
- Exposure to virus in the around time of delivery (mainly intrapartum) - most common (95%)
- Predominantly skin, eye and mouth (SEM) infections - vesicular lesions in these places
- Can also cause CNS and disseminated disease - meningoencephalitis, liver dysfunction
How is Chlamydia trachomatis transmitted to the neonate and what disease does it cause in the neonate?
- During delivery
- Causes neonatal conjunctivitis or pneumonia
NOTE: it is treated with erythromycin
Which mycoplasma species can cause neonatal infection?
- Mycoplasma hominis*
- Ureaplasma urealyticum*
Why are premature infants at increased risk of infection?
- Immune system less developed
- Less maternal IgG
- NICU care (exposure to microorganisms)
What is the definition of ‘early-onset’ infection?
Infection that occurs within 72 hours of birth
What are the three main organisms that cause early-onset infection?
- Group B Streptococcus
- E. coli
- Listeria monocytogenes
What type of bacterium is Group B Streptococcus?
Streptococcus agalactiae
- Gram-positive coccus
- Catalase negative
- Beta-haemolytic
What can GBS cause in neonates?
Most common causes of neonatal infection
- Sepsis
- Meningtits
- Pneumonia
What type of organism is E. coli and which diseases can it cause in the neonate?
- Gram-negative rods
- Can cause bacteraemia, meningitis and UTI
NOTE: the K1 antigen is particularly problematic
What type of organism is Listeria monocytogenes and what disease can it cause?
- Gram-positive rods
- Causes sepsis in the mother and the newborn
List some risk factors for early-onset sepsis.
- Prematurity
- Prolonged rupture of membranes
- Maternal pyrexia
- Previous history of neonatal GBS infection
- Maternal bacturia
- Foetal distress
List some investigations that may be useful in early-onset sepsis.
- Bloods
- Blood culture
- FBC, CRP
- Blood gases
- LP (meningitis)
- CXR (pneumonia)
Outline the treatment of early-onset sepsis.
- ABCDE
- Antibiotics - benzylpenicillin and gentamicin
- Benzylpencillin covers GBS and gentamicin covers E coli
What is late-onset sepsis?
Sepsis that occurs more than 72 hours after birth
What are the main causes of late-onset sepsis?
- Coagulase negative staphylococci (e.g. S. epidermidis)
- GBS
- E. coli
- Listeria monocytogenes
- S. aureus
- Enteroccocus sp.
- Gram-negatives (e.g. Klebsiella, Enterobacter, Pseudomonas)
List some clinical features of neonatal sepsis.
Non-specific
- Respiratory
- Distress: grunting, nasal flaring, recessions
- Apnoea
- Cardiovascular: tachycardia, hypotension, cool peripheries, increased CRT
- Irritability, poor feeding, lethargy
- Skin changes: jaundice, blue/mottled
- Temperature: can be high or low
- Seizures (meningitis)
List some investigations that may be used in late-onset sepsis in addition to the ones used in early-onset sepsis
- Urine MCS
- Swabs from an infected site
- ET swabs if ventilated
