RESP: Infections Flashcards
Pneumonia on a chest xray?
Consolidation and air bronchogram
Signs of pneumonia
Usually signs of sepsis: Tachycardia Tachypnoea Hypoxia Hypotension Fever Confusion
Chest signs of pneumonia
Bronchial breath sounds-
Focal coarse crackles
Dullness to percussion
Severity assessment for pneumonia
CURB-65 (CRB-65 in community) C- Confusion U- Urea> 7 R- RR> 30 B- BP < 90 systolic or < or equal to 60 diastolic 65- age greater than or equal to 65
What is atypical pneumonia?
Pneumonia caused by organisms that cannot be cultured by gram staining
What are bronchial breath sounds?
In pneumonia- harsh breath sounds equally loud on inspiration and expiration
What are focal coarse crackles?
Air passing through sputum in airways similar to using a straw blow air through a drink
What is CURB-65 for?
Predicts mortality: (1= 5% 3= 15%, score 4/5= 25%) and whether pt should be treated at hospital
0/1- consider treatment at home
greater than/equal to 2- consider treatment at hospital
greater than/equal to 3- consider intensive care assessment
How do you get Legionnaires’ disease?
Infected water supply or air condition units
What complication can Legionnaires’ disease cause?
i.e. note on bloods as a clue
Hyponatraemia–> SIADH
Lymphopenia
Typical Legionnaires’ exam patient?
Cheap hotel holiday and presents with hyponatraemia and lymphopenia
What are some investigations you might do for lung abscess?
CXR :
- Fluid-filled space within an area of consolidation
- air-fluid level is typically seen
sputum and blood cultures
Complications of mycoplasma pneumoniae?
haemolytic anaemia Erythema multiforme meningioenchepalitis Guillan barre syndrome bullous myringitis: painful vesicles on the tympanic membrane pericarditis/myocarditis gastrointestinal: hepatitis, pancreatitis renal: acute glomerulonephritis
Causative organism for fungal pneumonia?
Pneumocystis jiroveci
Who is at risk of fungal pneumonia?
Immunocompromised- esp HIV patients with low CD4 count
How does fungal pneumonia present?
Dry cough with sputum production
SOB on exertion
Night sweats
Complications of pneumonia?
Sepsis Pleural effusion Empyema Lung abscess Death
Causes of pneumonia?
Streptococcus pneumoniae (accounts for around 80% of cases)
Haemophilus influenzae
Staphylococcus aureus: commonly after influenza infection
atypical pneumonias (e.g. Due to Mycoplasma pneumoniae)
What is a lung abscess?
well-circumscribed infection within the lung parenchyma
What are the causes / RF for a lung abscess?
Secondary to aspiration pneumonia e.g.
Poor dental hygiene
stroke (reduced consciousness)
infective endocarditis - haematogenous spread
direct extension - empyema
Bronchial osbtruction (secondary to lung tumour)
What are some of the microbial causes of lung abscess?
often polymicrobial
Monomicrobial causes:
Staphylococcus aureus
Klebsiella pneumonia
Pseudomonas aeruginosa
What are some of the symptoms of lung abscess?
Develop over weeks (like subacute pneumonia)
Systemic: night sweats / weight loss Fever productive cough (foul sputum, rarely haemoptysis) chest pain SOB
What are some of the signs you would see on examination of a lung abscess?
dull percussion
bronchial breathing
clubbing may be seen
What are some investigatioins you might do for lung abscess?
CXR :
- Fluid-filled space within an area of consolidation
- air-fluid level is typically seen
sputum and blood cultures
How would you manage a lung abscess?
IV antibiotics
Percutaneous drainage may be required
Rare: surgical resection
What is a Parapneumonic effusion?
Parapneumonic effusions are effusions caused by an underlying pneumonia.
Simple - not infected
Complicated- effusion develops once infection has spread to the pleural space.
How is empyema, a simple parapneumonic effusion and complicated parapneumonic effusion related?
Three conditions = a spectrum of pleural inflammation in response to infection.
From a simple parapneumonic effusion to empyema.
What are RF for empyema ?
recent pneumonia iatrogenic intervention in the pleural space thorax trauma Immunocompromised e.g. diabetes co-morbidities make pneumonia more likely lung disease male sex young or old age alcohol abuse
If empyema or a complicated parapneumonic effusion is diagnosed what must be done urgently?
Insert a chest drain
+ long course of AB
if no improvement with AB and drainage - surgery or fibrinolytics
How do causative pathogens differ from comminity acquired and hospital acquired empyema?
Community: Streptococcus pneumoniae, and staphylococci
Hospital: staphylococci (particularly MRSA)
What is type 1 respiratory failure?
Pa02<8kPa; PaC02 Normal
Causes of type 1 respiratory failure?
Asthma Congestive HF Pulmonary Embolism Pneumonia Pneumothorax
What is type 2 respiratory failure?
Pa02<8kPa; PaC02 > 6kPa
Causes of type 2 respiratory failure?
Obstructive lung disease e.g. COPD
Restrictive lung disease e.g. IDL
Depression of respiratory centre e.g. opiates
NMJ disease e.g. Guillan barre syndrome, MND
Thoracic wall disease- rib fracture
What is ARDS?
Increased permeability of alveolar capillaries–> fluid accumulation in alveoli- non-cardiogenic pulmonary oedema
Causes of ARDS?
Pulmonary: chest sepsis, aspiration, pneumonia, trauma, smoke inhalation
Non-pulmonary: DIC, acute pancreatitis, drug OD
Presentation of ARDS?
Acute onset respiratory failure which fails to improve with supplemental O2.
Symptoms of severe dyspnoea, tachypnoea, confusion and presyncope
Examination findings in ARDS?
fine bibasal crackles but no other signs of HF
Investigations for ARDS?
Cxr with bilateral alveolar infiltrates w/o any other features of HF
Management of ARDS
V serious ICU Ventilatory support Haemodynamic support DVT prophylaxis Abx only if infectious cause for ARDS
(SARS-CoV-2) can cause viral pneumonia. What is the triad of symptoms hospitalised patients get?
Hypoxia
Lymphopenia
Bilateral, lower zone changes on CXR
What is hospital management for SARS-CoV-2?
- O2 supplementation
some may need CPAP / invasive ventilation - Dexamethasone ( consider Tocilizumab +/- Remdesivir)
- AB may be needed if superadded bacterial infection
What is Influenza?
Flu
Single stranded RNA virus.
most common cuaes of viral pneumonia in immunocompromised adults
What serotypes of inluenza are there?
Three serotypes of influenza - A, B and C
Serotype- determined by surface antigens haemagglutinin and neuraminidase. These are rearranged in host organisms e.g. birds /animals = different strains e.g. Influenza A H5N1 (avian influenza)
How is influenza transmitted?
via respiratory secretions
VVV contagious
How long is incubation period for influenza?
typically 1-4 days
How long is a pt infectious for with influenza after incubation period ?
patients can remain infectious for 7-21 days
What are the symptoms of influenza?
Fever ≥ 37.8°C
Non-productive cough
Myalgia
Headache
Malaise
Sore throat
Rhinitis
What are some pulmonary complications of Influenza?
Viral pneumonia,
secondary bacterial pneumonia,
worsening of chronic conditions e.g. COPD and asthma
What are some Cardiovascular complications of Influenza?
Myocarditis
Heart failure
What are some neurological complications of Influenza?
Encephalopathy
What are some GI complications of Influenza?
Anorexia and vomiting are common
How do you diagnose Influenza?
Routine viral culture
Rapid reverse transcriptase PCR tests are now available.
What is the management of Influenza?
- Supportive (analgesia, antipyretic, fluids, oxygen)
- Antiviral treatment with neuraminidase inhibitors e.g. Oseltamivir (‘Tamiflu’)
- Infection control and respiratory isolation to prevent onward transmission
What are the vaccine options for Influenza? Who is it recommended for?
- Inactivated vaccine tailored each year according to recent outbreaks.
It provides partial protection against influenza - those over 65, with chronic conditions. Healthcare workers and nursing home residents.
What are some general clinical features of TB?
- Fever
- Night sweats
drenching) - Weight loss (weeks – months)
- Malaise
What are some clinical features of Respiratory TB?
cough ± purulent sputum/haemoptysis
pleural effusion
What are some clinical features of NON- Respiratory TB?
Skin (erythema nodosum)
Lymphadenopathy;
Bone/joint; (stiffness, abscess, swelling)
Abdominal; (pain/diarrhoea/distention)
CNS
(meningitis);
Genitourinary; (flank pain, dysuria, polyuria)
Miliary (disseminated);
Cardiac (pericardial effusion)
What are you differentials for Haemoptysis : infection related?
Pneumonia
Tuberculosis
Bronchiectasis / CF
Cavitating lung lesion (often fungal
What are you differentials for Haemoptysis : Malignancy related?
Lung cancer
metastases
What are you differentials for Haemoptysis : Haemorrhage related?
Bronchial artery erosion
Vasculitis
Coagulopathy
What are some differentials for Haemoptysis? Other (resp = clue)
PE!
List some RISK FACTORS for TB ?
Past history of TB
TB contact
Born in a country with high TB incidence
Travel to country with high incidence of TB
Immunosuppression–e.g. IVDU, HIV, organ transplant, renal failure/
dialysis, malnutrition/ low BMI, DM, alcoholism
What are the immediate management principals for a pt with Resp TB (before investigations)
ABCDE approach
Admit to side room + start infective control measure (e.g. masks + negative pressure room.)
What are the management principals for a pt with Resp TB (lab investigations)
- Productive cough - 3 x sputum samples (acid-fast Ziehl-Neelsen stain) + TB culture
- NO productive cough - consider bronchoscopy
- Routine bloods
LFTs + HIV test + vit D levels
What are the management principals for a pt with Resp TB (imaging)
- CXR
- Consider CT chest if suspect pulmonary TB (CXR normal / no clinical features)
What to do if your diagnosis is split between pneumonia and TB?
Start Antibiotics for pneumonia as per CURB-65
What should you do if pt is critically unwell and there is a likelihood of TB?
Start TB treatment AFTER samples sent
How long does TB culture take? What does this mean?
Culture takes 6-8 weeks.
Means treatment often started before confirmed diagnosis.
Novel PCR test (Gene Xpert) available in some centre - gives immediate info on drug sensitivites / resistance.
What role do specialist nurses play in TB management?
Notify pt cases to specialist nurses as they:
support pt during investigation, treatment, pubic health issues AND initiate contact tracing!
What is standard Anti-TB therapy regimen?
FIRST 2 MONTHS:
4: (Rifampicin, Isoniazid, Pyrazinamide, Ethambutol)
NEXT 4 MONTHS
2: (Rifampicin, Isoniazid)
TOTAL: 6 months minimum (can vary)
Why is weight important in Anti-TB therapy?
dose of anti-TB is weight dependant.
Which bloods is it essential to check before commencing anti-TB treatment?
LFTS
Which anti-TB drug requires eye test?
Ethambutol (E for eyes)
need to check visual acuity before giving.
Side effect - can cause Retrobullar neuritis
What strategies can be used to ensure compliance ?
Directly observed Therapy (DOT)
What investigation if suspect CNS TB?
MRI Brain
What are major side effects of Rifampicin?
Hepatitis
rashes
febril reactions
orange / red secretions - sweat / urine / contact lenses
Drug interactions - warfarin / COCP
What are major side effects of Isoniazid?
Hepatitis
rashes
peripheral neuropathy
psychosis
What are major side effects of Pyrazinamide?
Hepatitis
rashes
vomitting
arthralgia
