Paediatrics Flashcards
Causes of Pneumonia in a Newborn
Organisms from the mother’s genital tract, particularly group B streptococcus but also Gram-negative enterococci and bacilli
Causes of Pneumonia in Infants and young children
Respiratory viruses, particularly RSV are most common.
Bacterial infections include Streptococcus pneumoniae or H. influenzae. Bordatella pertussis and Chlamydia trachomatis can also cause pneumonia at this age. An infrequent but serious cause is Staphylococcus aureus.
Viruses are the most common cause in younger children, whereas bacterias are more common in older children.
Causes of Pneumonia in children over 5 years
Mycoplasma pneumoniae, Streptococcus pneumoniae and Chlamydia pneumoniae are the main causes.
Viruses are the most common cause in younger children, whereas bacterias are more common in older children.
Clinical features of Pneumonia
Fever, cough and rapid breathing usually preceded by a URTI.
O/E Tachypnoea Nasal flaring Chest indrawing. End inspiratory coarse crackles over affected area
Classic signs like consolidation with dullness on percussion, decreased breath sounds, bronchial breathing may be absent in children.
In contrast to asthma, the most sensitive clinical sign of pneumonia in children is increased RR
Indications for admission for suspected Pneumonia
O2 sats <92%
recurrent Apnoea
grunting and or inability to maintain adequate fluid/feed intake
Antibiotics for Pneumonia in newborns, older infants and children
newborns - broad-spectrum IV antibiotics
older infants - oral amoxicillin with broader spectrum antibiotics like co-amoxiclav reserved for complicated/unresponsive pneumonia
children - amoxicillin or oral macrolide such as erythromycin.
There is no advantage in giving IV rather than oral treatment in mild/moderate pneumonia
In pneumonia, small parapneumonic effusions occur in up to one-third of children and may resolve with appropriate antibiotics. What does a persistent fever despite 48 hrs of antibiotic suggest?
A pleural effusion requiring draining. This should be done with US guidance.
Placement of a small-bore chest drain and regular instillation of a fibrinolytic agent are usually effective. Video -assisted thoracoscopic surgery or thoracotomy and decortication is sometimes necessary in refractory cases.
There may be blunting of the costophrenic angle on the chest X-ray. Some of these effusions develop into empyema and fibrin strands may form, leading to septations - These are formed from fibrin and divide the fluid into separate pockets
What does decortication mean?
Decortication is a medical procedure involving the surgical removal of the surface layer, membrane, or fibrous cover of an organ. The procedure is usually performed when the lung is covered by a thick, inelastic pleural peel restricting lung expansion.
Which children require follow-up after having pneumonia?
Those with evidence of lobar collapse or atelectasis should have a repeat chest X-ray after 4-6 weeks to check that the lung fields look normal
Follow-up is not generally erquired for children with simple consolidation on chest X-ray.
Virtually all children make a full recovery.
Chronic lung infections cause a persistent ‘wet’ cough and require further investigation. What are some common organisms that cause persistent bacterial bronchitis?
In persistent bacterial bronchitis, there is persistent inflammation of the lower airways driven by chronic infection.
Commomn organisms are:
Haemophilus influenze
Moraxella catarrhalis
It may be a precursors to bronchiectasis if investigations and treatment are not instituted.
How are chronic lung infections investigated and treated?
Referral to a specialist in paediatric respiratory disorders
Bacterial growth from bronchial lavage/sputum
Treatment with high dose antibiotics such as co-amoxiclav
physiotherapy.
What do bronchiectasis and persistent bacterial bronchitis cause in children?
Chronic lung infections with a persistent wet sounding cough.
Cystic fibrosis
Primary ciliary dyskinesia
Immunodeficiency
Chronic aspiration
all cause what type of bronchiectasis?
Generalized bronchiectasis.
A plain X-ray may show gross bronchiectasis
Focal bronchiectasis is due to…?
previous severe pneumonia
congenital lung abnormality
obstruction by a foreign body.
A plain X-ray may show gross bronchiectasis.
Bronchoscopy is usually indicated to exclude a structural cause.
What is the epidemiology of Cystic fibrosis and is it autosomal dominant or recessive?
CF is the most common life-limiting autosomal recessive condition in caucasians with an incidence of 1 in 2500 live births and a carrier rate of 1 in 25. It is less common in other ethnic groups. Life expectancy has increased with a projected life expectancy for current newborns into the 40s.
A defective protein called CF transmembrane conductance regulator (CFTR), a cyclic AMP-dependent chloride channel found in the membrane of cells is the cause of what illness?
Cystic fibrosis
The gene for CFTR is located on what chromosome?
Chromosome 7. Over 900 different gene mutations have been discovered. By far the most frequent mutation (78%) is ΔF508
In cystic fibrosis, different mutation classes of the CFTR protein can cause either reduced amounts of functional CFTR or a normal amount of CFTR with reduced function. Newer therapies are targeting specific classes of mutation.
How many specific classes of mutation are there?
6
Drugs are classified as CFTR potentiators and correctors.
Potentiators e.g. Ivacaftor are helpful in class III (channel opening defect) and IV (pore abnormality)
Correctors e.g. Lumicaftor are helpful in class II (ΔF508; incorrectly folded, cannot traffic to membrane)
