Paediatrics Flashcards
When can jaundice in a neonate be aetiologically normal
After 24 hours
How does rhesus haemolytic disease occur
Mum = rhesus negative
Baby = rhesus positive
Sensitising event eg trauma/abruption (baby’s blood exposed to mothers)
Mother develops antibodies against the baby’s blood = haemolytic anaemia
Unconjugated bilirubin is produced
How is rhesus haemolytic disease prevented
With anti-D immunoglobulin:
At 28 weeks
After sensitising events
One dose after birth if the mother is known to be rhesus negative
When does ABO incompatibility occur
Mother = type O = can develop anti-B or anti-A antibodies
Baby = type A or B
How is ABO incompatibility diagnosed
Coomb’s test
Which infections are included in TORCH
Toxoplasmosis
Other (syphilis, parvovirus, varicella zoster)
Rubella
CMV
Herpes; Hepatitis
Genetics of G6PD deficiency
X linked recessive
Genetics of hereditary spherocytosis
Autosomal dominant
Causes of jaundice under 24 hours
Rhesus haemolytic disease
ABO incompatibility
TORCH infections
G6PD deficiency
Hereditary spherocytosis
Causes of jaundice in the first 2-14 days (normal)
Physiological jaundice
Breast milk jaundice
Exacerbation by bruising and polycythaemia
Infection
Two main reasons for physiological jaundice
Increased bilirubin production as fetal haemoglobin has a lifespan of 70 days (compared to adult 120)
Decreased conjugated bilirubin due to liver immaturity (why premature babies have a higher incidence)
Why can breast milk feeding difficulties or infection cause jaundice in neonates
Feeding difficulties and infection cause dehydration which impairs bilirubin elimination
Why can polycythaemia occur in neonates
Gestational diabetes
Why can bruising occur in neonates
Caput
Cephalohaematoma
What is neonatal biliary atresia
Rare condition with failure of the biliary tree to develop
NB: Important to detect early as early surgery improves outcomes
Pathophysiology of kernicterus
Acute bilirubin encephalopathy: brain damage due to unconjugated bilirubin deposition in the basal ganglia and brain stem after it exceeds albumin binding capacity
Complications of kernicterus
Seizures, hypotonia, opisthotonos
Without treatment: cerebral palsy, learning disabilities, sensorineural deafness
Investigations of neonatal jaundice
Transcutaneous bilirubin levels
Bloods: coombs, kleihauer, U&Es (both conjugated and unconjugated bilirubin), FBC + blood film, blood cultures, TFTs
USS if there is a suspicion of biliary atresia
Treatment of neonatal jaundice
First line phototherapy: converts unconjugated bilirubin into harmless substances
Exchange transfusion: if bilirubin levels are very high
Clinical features of bronchiolitis
LRTI
Coryzal symptoms preceding a dry wheezy cough
Fever + poor feeding
Tachypnoea, tachycardia
Symptoms of RDS e.g. intercostal/subcostal recessions, tracheal tug, grunting, nasal flaring
When should you suspect pneumonia in a differential diagnosis of bronchiolitis
High fever
Localised signs (consolidation)
High risk children for bronchiolitis
congenital heart disease
BPD (bronchopulmonary dysplasia)
CF
prematurity
Prevention of bronchiolitis in high risk children
IM palivizumab (RSV monoclonal antibody)
Most common causal organism of croup/laryngotracheobronchitis
Parainfluenza virus
Clinical features of croup
URTI
Barking cough
Inspiratory stridor
Hoarse voice
Respiratory distress
Differential diagnosis of croup
Bacterial tracheitis – more toxic appearance
Laryngomalacia – no chest signs
Treatment of croup
Reassurance
One of dose of oral or nebulised steroids e.g. dexamethasone 150mcg/kg
Treatment of severe croup unresponsive to steroids
Hospital for nebulized adrenaline
Careful monitoring
Most common causal organism of epiglottis
Haemophilus influenzae
rare now due to the Hib vaccine
Clinical features of epiglottis
Toxic looking child - miserable fever
3 Ds: drooling, dysphagia, distress
Tripod position
Muffled voice
Inspiratory stridor
Epiglottis treatment
IV cefotaxime
Do not distress the child or examine the airway
Causes of meningitis/encephalitis under 3 months of age
Group B strep
Causes of meningitis over 3 months of age
Meningococcus, pneumococcus (haemophilus influenza b)
Mumps virus
RNA paramyoxovirus
Clinical features of mumps
Coryzal symptoms followed by parotid swelling
Ear ache
Trismus – spasm of the muscles of mastication when chewing
Complications of mumps
Meningitis
Encephalitis
Orchitis
Pancreatitis
Measles virus
RNA paramyxovirus: morbillivirus
Clinical features of measles
Catarrhal stage:
- 4 Cs – Cough, Cranky, coryza, conjunctivitis
Exanthematous stage:
- maculopapular rash with cephalocaudal progression
Complications: - most common is otitis media
Diagnosis of measles
Clinical diagnosis
Saliva swab for measles IgM to confirm since it is a notifiable disease
Rubella virus
RNA paramyxovirus – rubivirus
Clinical features of rubella
Coryzal prodrome
Pink maculopapular rash
Lymphadenopathy – sub occipital or posterior auricular
Arthralgia is common
Diagnosis of rubella
Clinical
Saliva swab for rubella IgM since it is a notifiable disease
Main risk group for rubella
Pregnant women:
<13 weeks: transmission to fetus is 80% (TOP can be offered)
>16 weeks: 25% risk of transmission/unlikely to cause defects
Clinical features of congenital rubella
Triad:
sensorineural deafness
cardiac abnormalities
eye abnormalities e.g. cataracts
Clinical features of parvovirus B19/fifth disease
Coryzal prodrome, fever
Malar rash
Glove and stocking erythema is also common
Arthropathy is common in older children
Once the rash appears they are no longer infectious
Complications of parvovirus B19
Pure red cell aplasia (high risk - sickle cell, thalassaemia)
Transient aplastic crisis (high risk - HIV, organ transplant patients)
Hydrops fetalis (> 70% transmission rate to the fetus if > 16 weeks - may require fetal blood transfusions in utero)
Causal organism of hand, foot and mouth
enteroviruses - mostly coxsackie A16
Are most sore throats viral or bacterial
viral
Causal organism of bacterial tonsilitis
group A beta haemolytic strep (GABHS) – strep. Pyogenes
Tonsilitis ‘Fever PAIN’ score
Fever
Purulent tonsils
Attended rapidly (within 3 days)
Inflamed tonsils
No cough or coryza
Score 2/3 = 30 – 40% chance of strep
Score 4/5 = 60% chance of strep
Treatment of tonsilitis
Bacterial:
Phenoxymethylpenicillin (pen V) for 7 – 10 days
Clarithromycin if penicillin allergic
Causal organism of scarlet fever
GABHS (group A B-haem strep) - release endotoxins that cause scarlet fever
clinical features of scarlet fever
Rash 12 – 48 hours after the onset of a sore throat
Red pin prick blanching red
Sandpaper feel to the rash
Strawberry tongue
Circumoral pallor
Treatment of scarlet fever
phenoxymethylpenicillin
(same as tonsilitis)
Causal organism of chickenpox
varicella zoster virus
Description of chickenpox rash
Macular – papular – vesicles (fluid filled)
Treatment of chickenpox
Supportive
Signs of infection (staph. Aureus) – flucloxacillin
Immunocompromised – acyclovir
Pregnant women contacts – VZIG or acyclovir if they develop a rash
3 complications of chickenpox
bacterial infection
pneumonia
encephalitis
causal organism of impetigo
staph aureus
peak ages of impetigo
2-5 years old
clinical features of impetigo
Pustules + blisters on an erythematous base
Blisters leave a brown ‘honey crust’ when they burst
treatment of impetigo
First line – topical hydrogen peroxide 1% or topical fusidic acid (both are just as effective)
If severe/widespread – oral flucloxacillin
school exclusion in impetigo
48 hours after antibiotics or until lesions have crusted over
school exclusion in mumps
7 days
school exclusion in measles
5 days after rash onset
school exclusion in rubella
5 days after rash onset
school exclusion in hand, foot and mouth
no school exclusion
Transient synovitis/irritable hip clinical features
Pain mostly on movement, improves throughout the day - will move it if persuaded!
2-12 years old
aetiology of transient synovitis/irritable hip
viral infection
management of any suspicion of septic arthritis or hip pain in a child < 3 years old
A&E
Perthe’s disease clinical features
Constant pain
Restricted ROM
Leg length discrepancy = late sign
5-10 years old
Dx + Ix Perthe’s disease
X ray – joint space widening/irregularity
- crescent sign (late sign)
SCFE clinical features
Vague pain
Drehmann’s sign
5-10 years old
overweight
pubertal
Dx + Ix SCFE/SUFE
X ray = diagnostic
Tx SCFE
Surgical fixation
Septic arthritis causal organism in children (most commonly <2 yrs old)
Staph aureus