Infections - comm acq pneumonia - PD Flashcards
Inf markers - systemic?
Fever
Rigor
Chills
Myalgia
Malaise
Headache
Anorexia
Delirium
Inf markers - local/peripheral
Erythema
Pain
Heat
Swelling
Pus
Inf markers - vital signs
change in body temp
Tachycardia
Hypotension
Tachypnoea
Inf markers - Haematology
Increase WBC count
Change to neutrophils (generally increase but low in neutropenic sepsis)
Increased platelets
Inf markers - Biochemistry
- Increased C reactive protein
- Increased erythrocyte sedimentation rate
- Increased serum creatinine
- Increased liver function test
- Change to procalcitonin level
inf markers - Microbiology tests
Presence of organism
Microscopy
Culture
Serology
Polymerase chain reaction
inf markers - Urinalysis
Presence of leucocyte esterase
Presence of nitrates
examples of respiratory infections
- Covid 19
- Infective exacerbation of COPD
- Tuberculosis (TB)
- Bronchiectasis
- Empyema
- Acute bronchitis
- Influenza
- Pleurisy
- Pneumonia (community acquired)
What is pneumonia?
- ‘Inflammation of the lungs caused by a bacterial or viral infection, in which the air sacs fill with pus and can become solid’
children under 5 and adults over 70 - highest mortality
both lungs definition and single lung?
bilateral pneumonia
unilateral pneumonia
3 categories
- CAP
- HAP (hospital)
- Aspiration pneumonia
CAP - symptoms?
- Overgrowth of pathogenic bacteria in upper resp tract – leading to infection
- Bacteria responsible depends on local epidemiology
- Severity depends:
Invading organism and response antimicrobial treatment
Patients underlying co-morbidities
Presence of risk factors
CAP Risk factors
- Age >65
- PMHx of COPD
- Cigarette smoke
- Care homes
- Alcohol abuse
- Use of acid-reducing drugs – stomach acid decrease allows pathogens to colonise upper resp tract more easily (GIS ISU)
Diagnosis and assessment?
- Thorough history from patient – including HxPC
- Blood tests (CRP+, WCC +)
- Patient observations
1. BP
2. HR
3. Resp rate
4. Temp
5. O2 sat - Chest X-ray – shows new signs of consolidation
1. Within 4 hours of presentation
2. Within 1 hour if suspecting sepsis
Differential Diagnosis?
- Covid 19 associate CAP – treatment differ
- Acute bronchitis
- Infective exacerbation of COPD
- Tuberculosis
- Empyema
- Lung cancer
- Pulm Emb
Treatment?
- Severity of patients condition can be calculated on scoring system but clin judgement also advised
- Patient gets 1 point if they have any of the following parameters
CURB - 65 - hospital
CRB – 65 (primary care). (prediction of >18 years pneumonia mortality risk)
C – Confusion
U – Urea > 7.0mmol/L
R – Resp rate >30 / min
B – Blood pressure
1. Low systolic <90 mmHg
2. Low diastolic <60 mmHg
65 – Age > 65 years
CRB – 65 scoring
- 0 – low severity - <1% mortality
- 1-2 – Intermediate – 1-10% mortality
- 3-4 – High - >10% mortality
CURB – 65 scoring
- 0-1 – low severity - <3% mortality
- 2 – Intermediate – 3-15% mortality
- >3 – High - >15% mortality
use of CRB - 65
- Use to help guide mortality risk, place of care and antibiotics.
Confusion?
(abbreviated mental test score <8 – age, time, address for recall at end of test. Year, place, identification of 2 persons, DOB, year of WW1, present monarch, count backwards 20-1)
Score 3-4?
urgent hopsital admission
- Clinically assess need for dual therapy to cover atypical infections if high CRB65 score. However, mycoplasma infection is rare in over 65s.
- Give safety net advice and likely duration of different symptoms, such as cough 6 weeks
- If recent influenza infection, consider need for anti-staphylococcal cover e.g doxycycline monotherapy or addition of flucloxacillin to standard treatment
- If failure of first-line agents, patients should be reassessed for on-going signs of infections before further treatment is prescribed
- British HIV association recommend testing for HIV in adult patients presenting with CAP
If CRB is 0?
Treat at home
First line –
- Amoxicillin
- 500mg TDS
Second line (failure 1st line treatment/penicillin allergy/atypical pathogen suspected)
- Doxycycline
- 200mg stat then 100mg OD
- Clarithromycin
- 500mg BD
Third line (prev treatment failure)
- Co – trimoxazole
- 960mg BD
Treatment duration for all is 5 days. Stop antibiotic treatment after 5 days unless microbiological results suggest a longer course length is needed or the person is not clinically stable.
Amoxicillin?
Class: Penicillin
Side effects:
- Common
- GI issues: n+v, diarrhoea, abdominal pain
- Rash
- Yeast infections: oral thrush, vaginal candidiasis
- Uncommon (but severe)
- Anaphylaxis: severe allergic reaction
- Liver enzyme abnormalities
- Severe diarrhoea
Contraindication: - Allergy to penicillin or cephalosporins
- History of severe allergic reactions
- Mononucleosis – risk of skin rash
Cautions - Renal impairment
- Pregnancy – gen safe
- Breastfeeding – gen sfe – caution advised
- GI diseases – caution with history like colitis, antiobiotics can exacerbate issues
- Mononucleosis – more prone to developing rash
Doxycycline
Class: Tetracycline antibiotic
Side effects:
- Common
- GI: n+v, diar, abdominal discomfort
- Photosensitivity
- Oesophageal irritation- can cause irritation or ulceration in the oesophagus if not taken with enough water
- Skin rash
- Dizziness or vertigo
- Less common
- Anaphylaxis
- Liver toxicity
- Tooth discolouration
- Intracranial hypertension
- Superinfection
Contraindications - Pregnancy (esp 2nd and 3rd trimester): c/I due to potential to cause harm to foetus. Category D
- Children under 8
- Hypersensitivity to tetracyclines – if allergic reaction to similar don’t use
- Severe liver disease
Cautions - Renal impairment
- Pregnancy
- Breastfeeding
- Photosensitivty
- GI conditions
- Superinfection risk
Clarithromycin?
Class: Macrolide antibiotic
Side effects:
- Common
- GI issues + dyspepsia
- Taste disturbances
- Headache
- Rash
- Uncommon
- Hepatoxicity
- QT interval prolongation
- Severe allergic reaction
- Clostridium difficile-ass diarrhoea – disrupt normal gut flora
- Pancreatitis
Contraindications - Hypersensitivity to macrolides
- Severe hepatic impairment
- Concurrent use with certain meds – (ergotamine, pimozide, fentanyl, terfenadine)
Cautions - Renal impairment
- Liver disease
- Pregnancy – category C
- Breastfeeding – gen sfe – caution advised
- Cardiac arrythmias – monitor closely
- Drug interaction – CYP3A4 inhibitor and can increased plasma conc of certain drugs (statins, benzos, CCBs)
Cotrimoxazole?
Class: Combination antibiotic
Side effects:
- Common
- GI
- Rash
- Headache
- Fatigue
- Less common but severe
- Hypersensitivity reactions (Stevens-Johnson syndrome)
- Haematological reactions: leukopenia, thrombocytopenia, and agranulocytosis, aplastic anaemia
- Liver toxicity
- Renal impairment
- Hyperkalaemia
- Pneumonitis
- Blood dyscrasias
Contraindications:
- Hypersensitivity to sulfonamides or trimethoprim – contra ind in severe allergic reactions (anaphylaxis or S-J syndrome)
- Severe renal or hepatic impairment
- Folate deficiency
- Pregnancy (esp in the first trimester) – foetal harm
- Breastfeeding – gen not recommended esp in infants under 2 months
- Infants under 2 months of age – due to risk of kernicterus
Cautions
- Renal impairment
- Liver disease
- Elderly
- Glucose 6 phosphate dehydrogenase
- Pregnancy (2nd and 3rd)
- Alcohol consumption
- Drug interactions (warfarin, methotrexate, phenytoin)
Indications
- UTI
- Resp tract infections – pneumonia
- GI infections
- Ear
- Skin
- Prophylaxis
CRB – 65 score – 1 and at home?
First line –
- Amoxicillin
- 500mg TDS
- PLUS
- Clarithromycin
- 500mg BD
Second line (failure 1st line treatment/penicillin allergy/atypical pathogen suspected)
- Doxycycline
- 200mg stat then 100mg OD
Third line (prev treatment failure)
- Co – trimoxazole
- 960mg BD
Treatment duration for all is 5 days. Stop antibiotic treatment after 5 days unless microbiological results suggest a longer course length is needed or the person is not clinically stable.
CURB-65 score ? >3
- Non-pen allergic
- Co-amoxiclav
- PO – 625mg TDS (5 days)
- IV – 1.2g TDS (5 days)
- Clarithromycin
- PO/IV – 500mg BD
- Pen allergic
- Levofloxacin
- PO/IV – 500mg BD (all 5 days treatment)
Co-amoxiclav?
Class: Penicillin
Side effects:
- As per amoxicillin
- Hepatic disorders
Contra indications
- Hx of jaundice due to co-amoxiclav administration
Monitoring
- Liver function
Notes
- Allergy potential
Unlikely you will see co-amox for CAP in hospital setting, unless advised by microbiology consultant or for very specific indications
Why?
- High risk of clostridium difficile – infective diarrhoea often associated with the excess use of broad spectrum antibiotics
- High resistance rates beginning to develop
Amoxacillin 1g TDS plus
- Clarithromycin (PO/IV) 500mg BD
Levofloxacin?
Class: Quinolone
Side effects:
- GI upset
- QT prolongation
- Affect glucose control
- Photosensitivity reactions
- Eye disorders
- Headache
- Convulsions
- Tendon damage
- Serious musclo-skeletal and nervous system disorders
Fluoroquinolone antibiotics: must now only be prescribed when other commonly recommended antibiotics are inappropriate
Levofloxacin – MHRA warnings
1. Can induce cnvulsions
2. Tendon damage
- C/I in patients with Hx of quinolone induced tendon damage
- Patients >60 at an increased risk
- Risk increased when used with corticosteroids
- Stop immediately is tendonitis suspected
3. Increased Risk of aortic aneurysm/dissection
4. Increased risk of disabling, long lasting or irreversible adverse reactions affecting the musclo-skeletal and nervous system
- Patients should be provided with MHRA advice sheet outlining s/e to lookout for
Levofloxacin
Cautions
- Patients with QT prolongation risk factors
- Use in children
- Patients >60 - +s/e risk
- Disorders that pre-dispose patient to seizures: (epilepsy, alcohol dependence)
- Contra-indications – Hx of quinolone induced tendon damage
- Counselling: provide MHRA advice leaflet, look out for signs
- Monitoring: signs of s/e – discuss with the patient, renal function
Summary
0-1 (low severity)
Non-pen allergic
Amoxicillin (PO) – 500mg TDS
Pen allergic
Doxycycline (PO) – 200mg STAT, 100mg OD
OR
Clarithromycin (PO) – 500mg BD
2 (moderate severity)
Non-pen allergic
Amoxicillin (PO) - 500mg – 1000mg TDS
PLUS
Clarithromycin (PO) – 500mg BD
Pen allergic
Doxycycline (PO) – 200mg STAT, 100mg OD
OR
Clarithromycin (PO) – 500mg BD
> 3 (highest severity)
Non-pen allergic
Co-amoxiclav (IV) – 1.2g TDS
PLUS
Clarithromycin (PO/IV) – 500mg BD
Pen allergic:
Levofloxacin (PO/IV) – 500mg BD
Counselling
- Patient expectation in terms of symptom resolution should be addressed
- Symptoms resolution timeline
- 1 week: fever should have resolved
- 4 weeks: chest pain and sputum production should have substantially reduced
- 6 weeks: cough and breathlessness should have substantially reduced
- 3 months: most symptoms should have resolved but fatigue may still be present
- 6 months: most people will feel back to normal
