Childhood and Pregnancy Infections Flashcards
Why should all women be offered routine screening for asymptomatic bacteriuria by midstream urine culture early in pregnancy?
Identification and treatment of asymptomatic bacteriuria reduces the risk of pyelonephritis.
How is passive immunity acquired in the foetus?
Maternal immunoglobulin G (IgG) is transported across the placenta to offer short term passive immunity
What 3 infectious diseases are screened for during pregnancy?
- HIV
- Syphilis
- Hep B
These can all be passed from mother to baby during pregnancy and birth
Why is screening for rubella during pregnancy no longer offered?
MMR vaccine
What is TORCH an acronym for?
A group of diseases that cause congenital (present at birth) conditions if a foetus is exposed to them in the uterus.
T: Toxoplasmosis
O: Others (syphilis, HIV, Coxsackie virus, Hep B, Varicella-Zoster)
R: Rubella
C: Cytomegalovirus
H: Herpes simplex disease
What diseases come under ‘Other’ of the TORCH acronym?
syphilis, HIV, Coxsackie virus, Hep B, Varicella-Zoster
What is considered to be the newest member of TORCH infections?
Zika virus
How is the zika virus transmitted?
Mosquito bite –> travel history is key
How can Zika virus infection during pregnancy affect the foetus?
microcephaly and other severe foetal brain defects
How is toxoplasmosis transmitted?
Ingestion of oocysts
How can the TORCH infections affect babies?
Most of the TORCH infections cause mild maternal morbidity, but have serious feotal consequences: abortion, stillbirth, prematurity, IUGR, congenital malformations (microcephaly, intracranial calcifications).
What are the potential effects of infection with influenza during pregnancy?
o No teratogenesis confirmed
o Premature delivery may occur, as in any febrile maternal illness, increasing the perinatal morbidity and mortality.
o The clinical syndrome in the mother is self-limited unless pneumonia supervenes and in the newborns manifests as any form of sepsis
How can HIV and HBV pass from mother to baby?
can be passed in utero & postnatal via breast milk
Is screening for Group B Streptococci (GBS) routinely offered during pregnancy?
No; not until it is clear that antenatal screening for GBS carriage does more good than harm and that the benefits are cost-effective
If a woman in a previous pregnancy has had GBS carriage, what is the likelihood of maternal GBS in the next pregnancy?
50%
The women who have had a previous GBS carriage, they have 3 choices during their next pregnancy.
What are these?
- To not have intra-partum antibiotics
- To have intra-partum antibiotics
- Screening at 35-37 weeks and offer antibiotics to those who have GBS colonisation
What is chorioamnionitis?
Inflammation of umbilical cord, amniotic membranes/fluid, placenta
This is a common precursor to preterm labour
Symptoms of chorioamnionitis?
Maternal fever, uterine tenderness, tachycardia, purulent/foul amniotic fluid
Pathogenesis of chorioamnionitis?
Bacteria ascend from the female genital tract, through the cervix to the amniotic fluid to cause infection
Haematogenous (via blood) infection is rare e.g. Listeria monocytogenes
Risk factors of chorioamnionitis?
o Prolonged rupture of membranes –> most common
o Other risk factors include amniocentesis, cordocentesis, cervical cerclage, multiple vaginal examinations, bacterial vaginosis
Causative organisms of chorioamnionitis?
o Group B Streptococcus
o Escherichia coli
o Genital Mycoplasma (Mycoplasma hominis & Ureaplasma urealyticum)
Effects of chorioamnionitis on foetus?
Adverse outcome for the neonate; sepsis, pneumonia and long-term neurodevelopment disability
Treatment for chorioamnionitis?
o Intra-partum antimicrobials and delivery of the foetus
o Antimicrobials should be administered at the time of diagnosis (not after delivery)
What is puerperal endometritis?
Uterine infection (lining of womb) during puerperium from vaginal bacteria.
What is puerperium?
The period of about six weeks after childbirth during which the mother’s reproductive organs return to their original non-pregnant condition.
Morbidity of puerperal endometritis?
Puerperal sepsis is a major cause of maternal death
Risk factors of puerperal endometritis?
- Caesarean section, prolonged labour
- Prolonged rupture of membranes
- Multiple vaginal examinations
Clinical features of puerperal endometritis?
o Fever (38.5C in first 24h post-delivery or >38.0 for 4 hours, 24h+ after delivery) o uterine tenderness o purulent, foul-smelling lochia o increased white cell count o general malaise, abdominal pain
What is lochia?
Vaginal postpartum bleeding; the heavy flow of blood and mucus that starts after delivery.
Causative organisms of puerperal endometritis?
o Escherichia coli
o Beta-haemolytic Streptococci (Group B)
o Anaerobes
Treatment of puerperal endometritis?
Broad-spectrum intravenous antimicrobials (Clindamycin + Gentamicin) – continued until the patient has been apyrexial for 48h
What is early onset sepsis (EOS)?
- Sepsis usually within 72 hours (85% present within 24hours of birth)
- A major cause mortality and morbidity in new-born babies.
How is early onset sepsis typically acquired?
Organisms from maternal genital tract
Mortality rate of early onset sepsis?
1 in 4 babies who develop it, even when they are given antibiotics.
Major causative organisms of early onset sepsis?
o Coagulase-negative staphylococci o Staphylococcus aureus o E. coli o Klebsiella o Enterobacter o Pseudomonas o Candida
What bacteria is Group A Strep?
Streptococcus pyogenes
What bacteria is Group B Strep?
Streptococcus agalactiae
What is ‘Croup’?
- Childhood infection of URT
- Inflammation and narrowing of the subglottic region of the larynx
- It is most often caused by a viral infection.
Clinical features of ‘Croup’? What is the characteristic symptom?
- Characteristic barking cough
- Hoarseness
- Respiratory distress +/- fever +/- coryza
- Stridor
What is stridor?
a high-pitched, wheezing sound caused by disrupted airflow
What is otitis media?
Infection of the middle ear (common in children)
Clinical features of otitis media?
- Unusual irritability
- Difficulty sleeping
- Tugging or pulling at one or both ears
- Fever
- Fluid draining from the ear
- Loss of balance
- Unresponsiveness to quiet sounds or other signs of hearing difficulty
What is the leading cause of death in children under 5 years?
Respiratory viruses
What is the major causative organism behind lower RTIs in childhood?
RSV (63%)
What are the 3 major causative organisms behind lower RTIs in childhood?
- RSV (63%)
- Mycoplasma pneumoniae (9%)
- Streptococcus pneumoniae (8%)
What is bronchiolitis?
Inflammation of the smallest airways (bronchioles), typically in children younger than 2.
Clinical features of bronchiolitis?
- A seasonal viral illness characterised by fever, nasal discharge, and dry, wheezy cough.
- On examination there are fine inspiratory crackles and/or high-pitched expiratory wheeze
Causative organisms of bronchiolitis?
o Respiratory Syncytial Virus (RSV) o Metapneumovirus o Adenovirus o Para-influenza virus o Influenza o Rhinovirus
Is bronchiolitis an upper or lower RTI?
Lower
How does pneumonia typically present in infants and children?
Acute febrile illness, possibly preceded by typical viral URTI.
o Breathlessness (poor feeding)
o Irritability
o Sleeplessness
o Cough, chest or abdominal pain in older patients
o Audible wheezing is rare in LRTI, but can occur
What is ‘pertussis’?
‘Whooping cough’; highly contagious respiratory disease
What are the 3 clinical stages of pertussis?
- Catarrhal phase
- Paroxysmal phase
- Convalescent (recovering) phase
Describe the catarrhal phase of pertussis?
Cold-like (coryza, conjunctival irritation, occasionally a slight cough)
7-10 days
Describe the paroxysmal phase of pertussis?
Long duration (2-6 weeks); No fever
a series of rapid, forced expirations, followed by gasping inhalation; the typical whooping sound
Post-tussive vomiting common
Very young infants may present with apnoea or cyanosis in the absence of cough
What does ‘post-tussive’ mean?
occurring after a cough
What organism causes pertussis?
B. pertussis
How does meningitis present in newborns and infants?
Can have non-specific clinical presentation in newborns and infants:
o Fever
o Irritability
o Lethargy
o Poor feeding
o High pitched cry, bulging AF
o Convulsions, opisthotonos (muscle spasm)
Causative organisms of bacterial meningitis in neonates?
Causative organisms of bacterial meningitis in >1 month-5 year olds?
Neonates: Group B Streptococcus, Escherichia coli, Listeria monocytogenes
> 1 month-5 year olds: Streptococcus pneumoniae, Neisseria meningitidis
Causative organisms of viral meningitis in neonates and infants?
Enteroviruses (commonest, meningitis occurring in 50% of children <3 months), HSV, Influenza, EBV, adenovirus, CMV
What is meningococcaemia?
bloodstream infection caused by Neisseria meningitidis
What is meningitis B?
Meningitis caused by Neisseria meningitidis
What is meningitis C?
Meningococcal C infection is caused by bacteria called meningococcal type C
Symptoms of meningococcaemia?
o Fever, non-specific malaise, lethargy, vomiting, meningism, respiratory distress, irritability, seizures
o Maculopapular rash common early in disease
o Petechial rash seen in 50-60%
major causative organisms of UTIs in children?
Most are from ascending bacteria: E. coli (60-80%), Proteus, Klebsiella, Enterococcus, and Staphylococcus saprophyticus
Prevalence of UTIs in caucasian children vs African American children?
Caucasian children had a two- to fourfold higher prevalence of UTI as compared to African American children
Symptoms of UTI in:
a) older children
b) infants?
o Classic UTI symptoms in older children; Dysuria, frequency, urgency, small-volume voids, lower abdominal pain.
o Infants with UTIs have nonspecific symptoms; Fever, irritability, vomiting, poor appetite
Urine sampling options for UTIs in children/infants?
o A clean catch sample should be obtained
o If not possible, use non-invasive method i.e. Urine collection pad
o Do not use cotton wool balls, gauze or sanitary towels.
o If non-invasive method not possible, use catheter sample or suprapubic aspiration
What is impetigo?
highly contagious skin infection
2 major causative organisms of impetigo?
o Staphylococcus aureus
o Streptococcus pyogenes
Symptoms of impetigo?
o Classically ruptured vesicles with honey-coloured crusting
o May be bullous
o Commonly starts around face/mouth
Antibiotic treatment for impetigo?
Topical antibiotics or oral Flucloxacillin
What is Scarlet fever?
contagious bacterial infection that causes blotchy rash
Major causative organism of scarlet fever?
o Group A beta-haemolytic Streptococcus
o 2-4 days post-Streptococcal pharyngitis
Symptoms of scarlet fever?
o Fever, headache, sore throat, unwell
o Flushed face with circumoral pallor
o Rash appears on chest/abdomen, may extend to whole body
o Rough ‘sandpaper’ skin
o Desquamation after 5/7, particularly soles and palms
o White strawberry tongue
Antibiotic treatment for scarlet fever?
Penicillin
