Paediatrics Flashcards
Definition of Pneumonia
Inflammation of lung alveoli, impairs gaseous exchange as they’re filled with blood, mucous, fluid and/or cellular infiltrates.
Pathophysiology of Pneumonia
Invasion and growth of a pathogen in parenchyma of lungs = inflammation and infiltration by neutrophils.
neutrophils release cytokines which activate immune response and lead to pyrexia(FEVER)
fluid and pus accumulates in the alveoli = impaired gas exchange because diffusion distance increases and SA decreases.
leads to hypoxia
Risk Factors of Pneumonia
Age <5 or >65
Smoking
Recent RTI
Chronic respiratory disease
Immunosuppression
IVDU
Co-morbidities - diabetes, cvd
alcoholism
Aspiration risk - Parkinson’s or neuro disease, or oesophageal obstruction
3 classifications of Pneumonia
Hospital - Acquired - Acute Nosocomial LTRI 48 hrs after hospital admission.
Community Acquired - pneumonia acquired outside.
Aspiration - (Mendelson’s Syndrome) - Pts with dysphagia (stroke,dementia,epilepsy,ms,parkinsons, MND) - unsafe swallowing - food goes into bronchial tree. Patients with gastric emptying issues or issues with their cough could have oropharyngeal aspirators containing gastric acid and aerobic/anaerobic bacteria. - acid and bacteria = inflammation=chemical pneumonitis
Explain Hospital Acquired Pneumonia
48 hours after hospital admission
Early HAP - less than 5 of admission. - Strep pneumoniae cause.
Late HAP - over 5 days of admission
causes:
S aureus - including MRSA
Gram Neg : pseudomonas aeurginosa, Haemophilus influenzae
Intestinal Gram Neg bacteria: E coli, actinobacteria, klebsiella.
Explain Community Acquired Pneumonia
Similar to any other LTRI
common causes:
strep pneumoniae
haemophilus influenzae
s aureus and mrsa
chlamydia psittaci and clamydia pneumoniae
influenza virus
Risk Factors of Aspiration Pneumonia
Risk factors:
1. neuro abnormalities - impaired conciousness, stroke, myasthenia gravis, bulbar palsy (bilateral impairement of CN 9,10,11,12), MS, dementia, parkinsion, MND
2. alcoholism
3. general anaesthesia, surgery
4. achalasia
5. gord
6. intubation
7. poor dental hygiene and oral infection
8. impaired mucociliary clearance
Where does Aspiration Pneumonia most commonly affect?
Right middle and lower lung - wider and more vertical than left bronchus - facilitating passage of aspirates.
Causative Agents of Aspiration Pneumonia
Aerobic - strep pneumoniae, staph aureus, Haemophilus influenzae, pseduomonas, aeruginosa
Anaerobic - klebsiella (aspiration lobar pneumonia in alcoholics), bacteroids, prevotella, fusobacterium, peptostreptococcus
3 categories of causative agents of pneumonia
Bacteria - MOST COMMON CAUSE. - STREP PNEUMONIA (80%) - H INFLUENZAE - MYCOPLASMA PNEUMONIAE - S Aureus - legionella, klebsiella
Viruses - influenza (most common in adults), rsv, sars-cov2, parainfluenza
Fungi - very rare - pneumocystis jirovecci in HIv+ people with cd4+ count <200 cells/uL
Presentation of Pneumonia
Cough with purulent sputum
Dyspnoea
Chest Pain - pleuritic
fever
malaise
rigors - sudden cold and shivering followed by fever and excessive sweating
systemic infection signs - pyrexia, tachy, hypotension, confusion, tachypnoea
Examination Findings in Pneumonia
Low ox sats
Auscultation - reduced breath sounds bronchial breathing - hard and loud sounds on inspiration and expiration, crepitations
dullness on percussion
increased vocal resonance
pleural rub
Scoring System for Pneumina
CRB65
C - CONFUSION - MENTAL TEST SCORE <8/10
U - Urea >7 mmol/L
R - RESP RATE - >30/MIN
B - BP - <90mmHg (Systolic) and/or <60 mmHg diastolic
65 - >65 yrs
everything is 1 pt.
stratified for risk of death.
0 - mortality - <1%
1/2 - 1-10%
3/4 - >10%
in hospital curb65 otherwise CRB65
0 - 0.7%
1 - 3.2%
2 - 13%
3 - 17%
4 - 41.5 %
5 - 57%
Tx based on CURB 65
IF
0-1 - TREAT AS OUTPATIENT
2 - SHORT STAY IN HOSPITAL OR WATCH VERY CLOSE AS OUTPATIENT
3-5 - REQUIRES HOSPITALISATION WITH CONSIDERATION OF ICU.
Investigations of Pneumonia
ABG
BLOODS - FBC (WCC), U+E (curb65), LFT, ESR/CRP
BLOOD CULTURE
SPUTUM - for MC+S
NAAT - look for mycoplasma pneumonia
URINE ANTIGEN - for legionella and pneumococcal pneumonia
LEGIONELLA ANTIBODIES - for high risk pts.
CXR - identify lobar,multi-lobar, cavitation and signs of pleural effusion. consolidation is seen in infection areas and may also show effusion.
Management of Pneumonia (Adults)
CURB65 tells you level of care needed
0/1 - home care
2 - hospital care
3+ - icu
no matter severity:
1. o2 sats above 94% or 88% in copd.
2. maintain fluid balance
3. analgesia - if pleuritic chest pain. paracetamol sufficient.
low - severity CAP - 5 day abx
1. amoxicillin
2. erythromycin/clarithromycin or doxycycline if pt has penicillin allergy.
moderate - severity CAP - 5 DAY DUAL ABX THERAPY
AMOXICILLIN + ERYTHROMYCIN/CLARITHROMYCIN
DOXYCYCLINE IF PENICILLIN ALLERGY - REPLACE AMOXI
HIGH SEVERITY cap - 5 DAY COURSE OF DUAL ABX
1. CO-AMOXICLAV + ERYTHROMYCIN/CLARITHROMYCIN
SWAP AMOXI FOR LEVOFLOXACIN IF PENICILLIN ALLERGY.
PREGNANCY : GIVE ERYTHROMYCIN
IN Pneumonia management how should abx be given
orally if possible
if iv, review every 48 hrs consider switching
repeat cxr at 6 weeks after resolution - ensure consolidation has resolved and no underlying abnormality.
When should I repeat a cxr after tx of pneumonia
repeat cxr at 6 weeks after resolution - ensure consolidation has resolved and no underlying abnormality.
Management of CAP in children
1st line : amoxicillin
2. clarithromycin/erythromycin - added if no response to 1st line or if mycoplasma or chlamydia infection suspected.
3. co-amoxiclav if concomitant influence infection present.
Rules for discharge for pneumonia patient
if they have 2 or more of the following in the last 24 hrs do not dischage:
1. temp > 37.5
2. rr>24
3. hr>100bpm
4. sbp <90 mmHg
5. O2 sats <90% on room air
6. Abnormal mental status
7. cant eat without assistance.
explain Staphylococcal Pneumonia
Bilateral Cavitating Bronchopneumonia - necrotising pneumonia (2 terms of synonymous) - occurs due to infection from staph aureus.
occurs in immunocompromised pts as its an opportunistic bacteria (1/3 people carry staph aureus in nasal cavity)
risk increases in IVUD, ELDERLY, PTS WITH INFLUENZA INFECTION.
Explain Klebsiella Pneumonia
Cavitating pneumonia -often in upper lobes.
distinct sputum : RED-CURRANT JAM SPUTUM
KLEBSIELLA PNEUMONIAE INFECTION - GRAM NEGATIVE ROD
RF: IMMUNOCOMPROMISES (OLD, ALCOHOL, DIABETES), MALIGNANCY, COPD, LONG-TERM STEROID USE, RENAL FAILURE
COMPLICATIONS: EMPYEMA, LUNG ABSCESSES, PLEURAL ADHESIONS
Explain Mycoplasma Pneumonia
Atypical pneumonia - atypical organisms cause it. cant be detected on gram stain and cant be cultured using standard methods.
most common: mycoplasma pneumoniae, chlamydophila pneumoniae, legionella pneumophila.
doesnt impair activity - mild.
presentation of mycoplasma pneumonia
gradual and prolonged
- myalgia
- arthralgia.
- headache.
- Dry Cough
Complications of Pneumonia
- erythema multiforme - t4 hypersensitivity reaction - target lesions
- stevens - johnson syndrome - disorder of skin and mucous membranes.
- meningoencephalitis and guillan -barre syndrome
- bullous myringitis - painful vesicle on tympanic membrane.
- pericarditis/myocarditis
- hepatitis or pancreatitis.
- acute glomerulonephritis.
- autoimmune haemolytic anaemia
investigations of mycoplasma pneumonia
non culture based diagnosis
mycoplasma serology or pcr
cold agglutination test
cxr - bilateral consolidation
management of mycoplasma pneumonia
mycoplasma has no cell wall - resistant to b-lactam antibiotics
- tetracyclines or macrolides (erythromycin/clarithromycin) - appropriate choices.
explain pneumocystic jirovecci
unicellular eukaryote
most common opportunistic infection with AIDS
presentation:
1. dyspneoa
2. dry cough
3. fever
4. very few chest signs
extrapulmonary manifestations:
1. hepatosplenomegaly
2. lymphadenopathy
3. choroiditis
mx :
1. co-trimoxazole + adjuvant corticosteroids (if pO2 <9.3kPa)
2. iv pentamidine - severe case
3. All HIV PTS with cd4+ <200 - pcp prophylaxis
ix:
cxr - bilateral interstitial pulmonary infiltrates.
bronchoalveolar lavage BAL - induces sputum samples which are stained with grocott’s silver stain - characteristic MEXICAN HAT (SOMBRERO) APPERANCE)
explain legionella pneumonia
caused by legionella pneumophilia.
colonises water tanks. airconditioning systems.
no person-to-person transmission
explain chlamydophila psitacii pneumonia
acquired from infected birds - parrots, cattle, horses, sheep
results: lethargy, arthalgia, headache, anorexia, dry cough, fever
may result in hepatitis splenomegaly nephritis, IE, meningoencephalitis, rash.
Definition of Croup
Laryngotracheobronchitis
common childhood URTI
SEAL- LIKE BARKING COUGH
Epidemiology of Croup
6 months - 3 yrs (highest incidence at 2)
boys more than girls - 1.4:1
more common in late autumn.
Causative agents of Croup
Viral Infection
PARAINFLUENZA VIRUSE TYPE 1 AND TYPE 3 - MOST COMMON
INFLUENZA A AND B
RSV
ADENOVIRUS
DIPTHERIA - VERY RARE - BUT CONSIDER BECAUSE IF NO TX THEN EPIGLOTTITIS.
Pathophysiology of Croup
Infection leads to inflammation and oedema of airways = upper airway obstruction.
narrows the subglottic region (just below larynx) - causes stridor and a seal-like barky cough.
if obstruction worsens = respiratory failure.
classifications of croup
mild - seal like barky cough, no stridor, no suprasternal/intercostal recession, no distress or agitation.
moderate - seal-like barky cough, audible stridor, suprasternal/intercostal recession, no distress or agitation.
severe - seal-like barky cough, audible stridor, suprasternal/intercostal recession, agitation and lethargy.
impending respiratory failure - seal-like barky cough, audible stridor, suprasternal/intercostal recession, agitation and lethargy, asynchronous chest wall and abdominal movement, hypoxia and hypercapnia, tachycardia
Presentation of Croup
Symptoms are typically worse at night and agitation increases with severity of symptoms.
- barking cough
- stridor
- hoarse voice
- fever
- coryzal symptoms - rhinorrhoea, sneezing
- Lethargy
- Respiratory Distress - costal recession and asynchronous breathing movements may be present in progresses disease.
cyanosis indicates impending respiratory failure.
investigations of croup
clinical diagnosis - history and exam.
frightening child can worsen symptoms.
cxr - not needed - but if done youll see typical steeple sign on PA view.
Management of Croup
single dose of dexamethasone (0.15 mg/kg)
severe cases - hospital admission - give supplementary oxygen + nebulised budesonide or IM dexamethasone.
if significant concern or emergency tx , nebulised adrenaline with high flow ox
Definition of Asthma
Reversible obstructive airway obstruction.
2 distinct characteristics:
1. airway inflammation
2. airway hyper-responsiveness
classifications of Asthma
allergic (extrinsic) or non-allergic (intrinsic)
extrinsic triggers: dust mites, pet dander, pollen, mould
intrinsic: cold, humidity, exercise, pollution, smoke
risk factors of asthma
Fhx
exposure to triggers - possibly viral infection, allergy, nsaids/beta blockers.
exercise, cold air, emotion/laughter in kids
history of atopy - excema, allergic rhinitis.
smoking/vaping
respiratory viral infection early in life
what is allergic/atopic march
when eczema/atopic dermatitis progresses then you get allergic rhinitis then asthma.
Presentation of acute asthma
progressively worsening dyspnoea
accessory muscle usage
tachypnoea
cyanosis
on auscultation:
symmetrical polyphonic expiratory wheeze
silent chest - reduced air entry
chronic asthma presentation
episodic symptoms with intermittent exacerbations
diurnal variability - symptoms worse night and early morning (poss because colder). can be seasonal
dry cough
wheeze
dyspnoea
auscultaiton:
symmetrical polyphonic expiratory wheeze
diagnosis of asthma
can be diagnosed without confirmatory tests
3 algorithms - A B C
Clinical Assessment - wheeze,breathlessness,variation. triggers. personal or fhx of atopy
Physical Exam - symmetrical polyphonic expiratory wheeze
Objective tests:
under 5 - Manage symptoms
5-16 - spirometry, BDR, FeNO , peak flow variability
17+ - FeNO and spirometry , BDR, peak flow variability, bronchoprovocation/histamine challenge test/ methacholine challenge test
