lung infections Flashcards
how can you get pneumonia?
- community acquired
- hospital acquired
- other e.g aspiration
what is the key way to diagnose community acquired pneumonia?
prompt assessment and CXR on admission
then consolidation on CXR
what are the common differentials for consolidation on CXR?
- pneumonia
- TB (usually upper lobe)
- lung cancer
- lobar collapse (blockage of bronchi)
- haemorrhage
how can pneumonia be treated?
- CURB 65 score to guide management and risk stratify. Refer to ITU if curb score high.
- local antibiotic guidelines using CURB 65 and patient allergies
- ABCDE approach, don’t ignore signs of sepsis
- no delay with antibiotics or IV fluids if indicated
- CXR, FBC, U&E, CRP and sputum culture
- blood culture if febrile
- high curb score, do atypical pneumonia screen - serology and urine legionella test
- ABG if low sats
what fits into the CURB 65 scoring system?
CURB 65
C - confusion, MMT 2 or more points worse
U - urea >7.0
R - >30/min
B - < 90mmHg systolic or <60mmHg diastolic
65 - age over 65
what follow ups do you do for pneumonia?
- HIV test
- immunoglobulins
- pneumococcal igG serotypes
- haemophilus influenzae b igG
- follow up in clinic for 6 weeks with a repeat CXR to ensure resolution
what are the causes of non resolving pneumonia?
CHAOS
C - complication e.g empyema, lung abscess
H - Host. immunocompromised.
A - antibiotics. inadequate dose, poor oral absorption.
O - organism. resistant or unexpected organic not covered by empirical antibiotics.
S - second diagnosis e.g PE, cancer, organising pneumonia.
what are the clinical features of tuberculosis?
- fever and nocturnal sweats (drenching)
- weight loss (weeks-months)
- malaise
- respiratory TB = cough, +/- purulent sputum, pleural effusion?
- non respiratory TB = erythema nodosum, lymphadenopathy, meningitis, pericardial effusion. Systemic effects.
what are the differential diagnosis’ of haemoptysis?
infection
- pneumonia
- tuberclosis
- bronchiectasis/CF
- cavitating lung lesions (often fungal)
Malignancy
- lung cancer
- metastases
haemorrhage
- bronchial artery erosion
- vasculitis
- coagulopathy
other
- PE
what are the risk factors for TB?
- past history of TB
- known history of TB contact
- born in a country with high TB incidence
- foreign travel to a country with high TB incidence
- evidence of immunosuppression e.g organ transplant, HIV, IVDU, renal failure, malnutrition, low BMI, DM, alcoholism etc.
what are the management principles for respiratory TB?
- ABCDE approach and aim to culture whenever possible
- admit to side room and start infection control e.g masks
- productive cough, 3x sputum samples for AAFB (mycobacterium) and TB culture (ideally early morning samples)
- if no productive cough and pulmonary TB is suspected, consider bronchoscopy.
- routine bloods and HIV + vit D levels
- CT chest if pulmonary TB suspected but CXR and clinical features not typical
- MRI Brain/spine if Millary TB suspected
- if unsure if TB or pneumonia, treat for pneumonia while investigating TB still.
- if patient highly unwell and v likely TB start anti-TB therapy asap after sputum samples sent.
- TB culture can take 6-8 weeks so treatment is usually started before diagnosis confirmation.
what is used in anti TB therapy?
- 4 antibiotics for the first 2 months
RIPE = rifampicin, isoniazid, pyrazinamide, ethambutol - followed by 4 months on 2 antibiotics
RI - rifampicin and isoniazid - Pyridoxine also given while on isoniazid as prophylaxis against peripheral neuropathy
- treat for a minimum of 6 months in total
- check baselines LFT and monitor closely, in some cases, directly observed therapy (DOT) done for compliance
- provide leaflets on treatment and educate patient on ADRs
what are the ADRs of TB treatment?
Rifampicin - Hepatitis, rashes, febrile reaction, organs/red secretions, many DDI e.g with warfarin
Isoniazid - peripheral neuropathy, psychosis, rashes
pyrazinamide - hepatitis, rashes, vomiting, arthralgia
Ethambutol - retrobulbar neuritis
therefore must do vaseline visual acuity test and LFTs which must be monitored closely.
what is bronchiectasis?
chronic dilation of one or more bronchi.
the bronchi exhibit poor mucous clearance and there is predisposition to recurrent or chronic bacterial infection .
gold standard test = high resolution CT.
what are the causes of bronchiectasis?
- post infective e.g whooping cough, TB
- immune deficiency
- genetic/mucocilary clearance defects - e.g CF, young syndrome, primary ciliary dyskinesia
- obstruction e.g foreign body, tumour, extrinsic lymph node
- toxic insult e.g gastric aspiration, toxic chemicals/gases
- secondary immodeficiency e.g HIV
- rheumatoid arthiritis
- allergic bronchopulmonary aspergillosis
what are the commonest organisms to cause bronchiectasis?
- haemophilus influenzae
- pseudomonas aerguinosa
- moraxella catarrhalis
fungi e.g aspergilus, candida
non TB - mycobacteria
how is bronchiectasis managed?
- treat underlying cause
- physiotherapy for mucus clearance
- antibiotics according to sputum cultures/sensitivities for acute exacerbations
- supportive - flu vaccine, bronchodilators if required
what is cystic fibrosis?
an autosomal recessive disease leading to mutations in the cystic fibrosis transmembrane conductance regulator (CFTR).
This can lead to a multi system disease, most commonly affecting the respiratory and GI systems characterised by thickened secretions..
how is CF diagnosed?
one or more of
- history of CF in a sibling
- or positive newborn screening test result
and
- increase sweat chloride concentration (>60mmol) (SWEAT TEST)
- or identification of two CF mutations
- or demonstration of abnormal nasal epithelial ion transport.
how does CF present?
- meconium ileus in 15-20% of newborn CF infants. The bowel is blocked by sticky secretions. Signs of blockage include bilious vomiting, abdominal distension and delay in passing meconium.
- intestinal malabsorption. in 90% of CF patients. Main cause is deficiency in pancreatic enzymes.
- recurrent chest infection
- newborn screening
what are some features of cf?
- nasal polyps
- chronic sinusitis
- steatorrhoea
- osteoporisis
- finger clubbing
- male infertility
- abnormal sweat secretions |(high chloride)
what are some common CF complications?
1) resp infections. Needs aggressive therapy with physio and antibiotics. Patients usually on prophylactic antibiotics.
2) low body weight
- may be consequence of pancreatic insufficiency, therefore give pancreatic enzyme replacement therapy
- high calorie intake needed and supplements
- may need NG or PEG feeding
3) distal intestinal obstruction syndrome (DIOS)
- faecal obstruction in ileocaecum (as opposed to constipation which is whole bowel)
- due to insufficient prescription of pancreatic enzymes/non compliance, also salt deficiency/hot weather
- symptoms, palpable mass in RIF and AXR will show mass to aid diagnosis
4) CF related diabetes
what lifestyle advice is given to patients with CF?
- no smoking
- avoid other CF patients
- avoid people with colds/infections
- avoid jacuzzis (psuedomonas)
- clean and dry nebulisers throughly
- avoid stables, compost or rotting vegetation (aspergillus fumigatus inhalation)
- annual influenza immunisation
- sodium chloride tablets in hot weather/vigorous exercise
