MI: Neonatal and Childhood Infections Flashcards
Which infections are screened for in pregnancy?
- HIVE
- Hepatitis B
- Syphilis
Which other congenital infections are known to cause issues in pregnancy/delivery?
- CMV
- HSV
- Toxoplasmosis
- Group B Streptococcus
- Hepatitis C
What does ‘TORCH’ stand for?
- Toxoplasmosis
- Rubella
- CMV
- HSV
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
- Choriodoretinitis
- Microcephaly/hydrocephalus
- Intracranial calcifications
- Seizures
- Hepatosplenomegaly/jaundice
What is the triad of features in congenital rubella syndrome?
- Cataracts
- Congenital heart disease (PDA is most common)
- Deafness
- Other features: microphthalmia, glaucoma, retinopathy, ASD/VSD, microcephaly, meningoencephalopathy, developmental delay
How is herpes simplex virus transmitted to the neonate?
- Lesions in the genital tract can transmit HSV to the neonate
- It causes a blistering rash and can cause disseminated infection with liver dysfunction and meningoencephalitis
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?
- Less maternal IgG
- NICU care (exposure to microorganisms)
What is the definition of ‘early-onset’ infection?
Infection that occurs within 48 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?
- Gram-positive coccus
- Catalase negative
- Beta-haemolytic
What can GBS cause in neonates?
- Bacteraemia
- Meningitis
- Disseminated infection
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 maternal risk factors for early-onset sepsis.
- Premature rupture of membranes
- Preterm labour
- Foetal distress
- Fever
- Meconium staining
- Previous history
List some baby-related risk factors for early-onset sepsis.
- Birth asphyxia
- Respiratory distress
- Low blood pressure
- Acidosis
- Hypoglycaemia
- Neutropaenia
- Rash
- Hepatosplenomegaly
- Jaundice
List some investigations that may be useful in early-onset sepsis.
- FBC
- CRP
- Blood culture
- Deep ear swab
- LP
- Surface swabs
- CXR
Outline the treatment of early-onset sepsis.
- ABCDE
- Nutrition
- Antibiotics
Which antibiotic combination is often used in early-onset sepsis and why?
- Benzylpenicillin and gentamicin
- Benzylpenicillin covers Group B Streptococcus whilst gentamicin covers E. coli
What is late-onset sepsis?
Sepsis that occurs more than 48-72 hours after birth
What are the main causes of late-onset sepsis?
- Coagulase negative staphylococcis (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 late-onset sepsis.
- Bradycardia
- Apnoea
- Poor feeding
- Irritability
- Convulsions
- Jaundice
- Respiratory distress
List some investigations that may be used in late-onset sepsis.
- FBC
- CRP
- Blood cultures
- MSU
- Swabs from an infected site
- ET secretions if ventilated
Outline the treatment of late-onset sepsis.
- Treat early with antibiotics
- Guidelines differ
- Example antibiotic regimen: 1st line = cefotaxime + vancomycin; 2nd line = meropenem
What are some common non-specific symptoms of infections in childhood?
- Fever
- Abdominal pain
List some investigations for meningitis in children.
- Blood cultures
- Throat swab
- LP
- Rapid antigen screen
- EDTA for blood PCR
- Clotted serum for serology
Why is it dangerous to perform an LP in meningococcal septicaemia?
They may be coagulopathic
The incidence of meningitis caused by which three agents has decreased in incidence since the introduction of vaccination programmes?
- Meningitis C
- Haemophilus influenzae type B
- Pneumococcus
What is the main bacterial cause of meningitis at the moment?
Meningitis B
What type of organism is Streptococcus pneumoniae?
- Gram-positive diplococcus
- Alpha-haemolytic
Which diseases can S. pneumoniae cause?
- Meningitis
- Pneumonia
- Bacteraemia
What type of vaccine is the S. pneumoniae vaccine?
- Conjugate vaccine
- Old version was called Prevenar 7 (7 serotypes), but a new version has been created call Prevenar 13
What type of organism is Haemophilus influenzae?
- Gram-negative cocco-bacilli
What are the typical causes of meningitis for the following age groups:
- Under 3 months
- 3 months to 5 years
- Over 6 years
Under 3 months:
- Neisseria meningitidis
- Streptococcus pneumoniae
- Haemophilus influenzae
- Group B Streptococcus
- Escherichia coli
- Listeria monocytogenes
3 months to 5 years:
- Neisseria meningitis
- Streptococcus pneumoniae
- Haemophilus influenzae
Over 6 years:
- Neisseria meningitis
- Streptococcus pneumoniae
What is the most common cause of death in:
- Postnatal children (1-59 months)
- Neonates
Postnatal children (1-59 months):
- Pneuomnia
- Followed by congenital anomalies
Neonates:
- Prematurity
- Followed by intra-partum complications
What is the most important bacterial cause of respiratory tract infection in children?
Streptococcus pneumoniae
Which children are mainly affected by Mycoplasma pneumoniae?
Older children (> 4 years)
Which group of antibiotics are used to treat Mycoplasma pneumoniae?
Macrolides
Describe the classical presentation of Mycoplasma pneumoniae.
- Fever
- Headache
- Myalgia
- Pharyngitis
- Dry cough
List some extra-pulmonary manisfestations of Mycoplasma pneumoniae.
- Haemolysis - IgM antibodies to I antigen on erythrocytes, cold agglutinins
- Neurological - encephalitis, aseptic meningitis, peripheral neuropathy, transverse myelitis
- Polyarthralgia
- Cardiac
- Otitis media
- Bullous myringitis (vesicles on the tympanic membrane - pathognomonic of Mycoplasma)
If a respiratory tract infection fails to respond to conventional treatment, which diagnoses should be considered?
- Whooping cough
- TB
How is UTI diagnosed in children?
- Symptoms
- Pure growth of > 105 CFU/mL
- Pyuria
What are the main organisms responsible for UTI in children?
- E. coli
- Other coliforms (Proteus, Klebsiella, Enterococcus)
- Coagulase-negative Staphylococcus (S. saprophyticus)
Why might renal tract imaging be useful in children who experience UTIs?
To check for congenital anomalies
What might recurrent childhood infections suggest?
Immunodeficiency
