Congenital, perinatal, neonatal infections Flashcards
What are examples of congenital infections
Rubella
Cytomegalovirus (CMV)
Toxoplasma gondii
Parvovirus
Varicella zoster
Syphilis
What are the features of congenital rubella infection
Risk and extent of foetal damage are determined by gestational age at onset of maternal infection
<8 weeks gestation:
- Deafness
- Congenital heart disease
- Cataracts
13-16 weeks gestation:
- Impaired hearing
- Beyond 18 weeks, risk to the foetus is minimal
What investigations and treatment should be done for rubella
Seroconversion on screening serology
Blood serology for IgM
Amniocentesis or CVS
PCR
Infant urine testing
Prevention via the MMR programme (13-14 months and 3 years)
What are the features of congenital CMV
Most common congenital infection (0.5/1000 in the UK)
DNA virus from the herpes family (HHV-5)
90% will have a normal birth and develop normally
5% have clinical features at birth
- Hepatosplenomegaly
- Petechiae
- Jaundice ± blueberry muffin rash
- IUGR
- Chorioretinitis → cataracts
- Neurodevelopmental disabilities e.g. sensorineural hearing loss, cerebral palsy, epilepsy, cognitive impairment
- PERIVENTRICULAR calcifications
5% develop problems later e.g. sensorineural hearing loss
What investigations should be done for congenital CMV
Seroconversion on screening serology
Blood serology for IgM
Amniocentesis or CVS
Infant urine testing for PCR
What is the management for congenital CMV
Infants: Early antiviral therapy with oral valganciclovir for 6 months or IV ganciclovir
+ audiology follow up
+ ophthalmology follow up
What is Toxoplasma gondii and what are the causes
Protozoan parasite
Consumption of raw or undercooked meat and contact with faeces of infected cats
Increased risk of vertical transmission with increasing gestational age (5% 1st, 80% 3rd trimester)
- Infection in 1st trimester- most likely to cause foetal damage but transmission rate is LOW (10%)
- In 3rd trimester- risk of foetal damage is low (10%) but transmission MUCH higher (85%)
Risk of congenital toxoplasmosis reduced with increasing gestational age (60-80% 1st, 5% 3rd)
What are the clinical features of congenital toxoplasmosis
Most infected infants are asymptomatic, but 10% may have manifestations such as (The 4C’s):
- Retinopathy, an acute fundal chorioretinitis, which sometimes interferes with vision
- Cerebral scattered calcification (Tram-like)
- Hydrocephalus (microcephaly)
- Convulsions
+ hepatosplenomegaly/jaundice
Infants will usually have long-term neurological disabilities e.g. deafness, low IQ, microcephaly
What are the investigations for congenital toxoplasmosis
Not usually screened
Sabin Feldmann Dye test
Bloods: IgM (active), IgG(immunity)
US: foetal anomaly scan
Amniocentesis + PCR to detect foetal infection
What is the management for toxoplasmosis
Pyrimethamine and sulfadiazine + calcium folinate for 1 year
Mother should avoid raw/rare meat and handling cats/cat litter
What are the features of parvovirus B19 infection
Up to 75% of women are immune to parvovirus B19
Infection is rare and usually uneventful
Can cause:
- Spontaneous miscarriage
- Stillbirth
- Hydrops fetalis (oedema and ascites from HF)
What is the management for antenatal parvovirus B19 infection
Infection identified → serial ultrasound monitoring to detect foetal anaemia and need for intrauterine transfusion
What are the features of congenital varicella zoster
<20 weeks
- Severe scarring of the skin
- Ocular damage
- Neurological damage
- Digital dysplasia
Last 4 weeks of pregnancy + 7 days after delivery - foetus is unprotected by maternal Abx
- Vesicular rash
- High mortality rate
What is the management for congenital varicella zoster
Varicella zoster Immunoglobulin
Treatment with aciclovir
Foetus: VZIG + monitoring + aciclovir for signs of infection
What are the features of congenital syphilis
Gram-ve spirochete (Treponema pallidum)
Transmission is via sexual contact, vertically, or blood-bourne
Rash on the soles of the feet and hands
Bone lesions
Bloody rhinitis
Hepatosplenomegaly
Glomerulonephritis
“Hutchinson’s teeth” (small, widely spaced, notched)
Frontal bossing of skull, saddle-nose
“Saber’s shins” (anterior bowing)
“Clutton’s joints” (symmetrical knee swelling)
What investigations should be done for congenital syphilis
Microbiolgy: Dark-ground (from chancre)
PCR +ve
Infant TP syphilis IgM test
What is the management for congenital syphilis
If mothers with syphilis identified on antenatal screening are fully treated 1 month or more before delivery, the infant does not require treatment and has an excellent prognosis
If there is any doubt about the adequacy of maternal treatment, the infant should be treated with penicillin.
IV benzylpenicillin
What are the risk factors for neonatal infection
Mothers previously had baby with invasive GBS
Current GBS colonisation, bacteriuria or infection in current pregnancy
Prelabour rupture of membranes
Intrapartum temperature ≥ 38oC or suspected chorioamnionitis
Rupture of membranes ≥ 18 hours
Premature (< 37 weeks)
Suspected or confirmed infection in another baby in case of multiple pregnancy
Why are preterm infants at an increase risk of infection
IgG is mostly transferred across the placenta in the last trimester, with no IgA or IgM transfer
Infection in or around the cervix is also a cause of preterm labour
Higher risk of nosocomial infection, often associated with indwelling catheters of mechanical ventilation
Contributes to bronchopulmonary dysplasia, brain injury and later disability
What are the causes of early neonatal sepsis
Early-onset (<72h after birth)
- Group B Strep
- E. Coli
- Klebsiella
- Pseudomonas
- listeria monocytogenes
Vertical exposure from ascending infection or exposure to high bacterial load during birth, after ROM
What are the causes of late-onset sepsis
Late-onset (>72h)
- Coagulase-negative staphylococcus (CONS) - staph. epidermis
- Staph aureus
- Enterococcus faecalis
- E. Coli
- Pseudomonas
- Klebsiella
Transmission from contamination by staff, ventral venous catheters, invasive procedures and tracheal tubes
What are the signs of neonatal sepsis
Respiratory distress: Tachypnoea (>60), Intercostal recessions, Grunting, Cyanosis
Temperature instability (hypothermia to hyperthermia)
Poor feeding, irritability, lethargy, drowsiness
Vomiting
Apnoea and bradycardia
Abdominal distension
Shock
Jaundice
Seizures
Meningitis: tense or bulging fontanelle, head retraction (opisthotonos)
What are the red flags for neonatal sepsis and what should be done if they are present
RR >60 min-1 or >5 below normal, or grunting
Oxygen needed to maintain saturations >92 %
Pale/mottled or non-blanching (purpuric) rash
Prolonged capillary refill >5 seconds
Hypotension
AVPU = V, P or U
Abnormal behaviour*
Blood lactate >2mmol/L
→ immediate sepsis 6 pathway
What is the management for neonatal sepsis
Admit
A-E
Involve seniors
Initiate sepsis 6 (Within 1 hours):
1. Administer high flow oxygen
2. Gain IV or IO access and order:
- Blood cultures (BEFORE Abx)
- Blood glucose, lactate (VBG/ABG), FBC, CRP, U&Es, Creatinine, Clotting screen
3. Administer broad-spectrum antibiotic* within one hour of sepsis recognition + monitor response by using CRP
4. Measure Fluids
- Given in hypotension or lactate >4mm/l
- Initial minimum 20ml/kg crystalloid 0.9% NaCl bolus over 5-10 minutes
- Vasopressors for hypotension that does not respond to fluid resuscitation
- Measure urine output
5. Involve seniors
6. Consider inotropic support
