Pneumonia, Tuberculosis and Lung cancer Flashcards
What is pneumonia ?
the inflammation of the lungs with consolidation or interstitial lung infiltrates most often categorises according to the causative organism
consolidation- refers to air sacs that should be filled with air now being filled with fluid
fluid fills the lungs in pneumonia
List some causes of pneumonia
atypical bacteria
legionella
severe acute respiratory syndrome
acute aspiration (dental elements)- aspiration pneumonia
aspergillosis
community acquired
hospital acquired
pneumocystis jirovecii
What is community acquired pneumonia?
this is pneumonia that is acquired outside of healthcare facilities
Who is most at risk of community acquired pneumonia?
those that are >65 years
more men at risk than women
residential home
COPD
cigarette smoke- smoking damages cilia; mucous left stagnant on respiratory membrane; increased risk of infection
alcohol abuse
poor oral hygiene
contact with children
diabetes
chronic disease
How does fluid appear on a chest x-ray ?
radiopaque
How does air appear on a chest x-ray?
radiolucent
What is the most common causative pathogen of community acquired pneumonia?
streptococcus pneumoniae (30-35%)
Name some atypical bacteria that can cause community acquired pneumonia (CAP)
mycoplasma pneumoniae (37%)
chlamydophila pneumoniae (5-15%)
legionella pneumophila (2-6% immunocompromised pts)
Viruses are responsible for around 10-30% of community acquired pneumonia. List some viral pathogens that can cause pneumonia
influenza virus A/B
respiratory syncytial virus
adenovirus
rhinobvirus
parainfluenza virus
5-13% of community are acquired pneumonia are polymicrobial. True or false
true
What are the mechanisms by which pathogens can reach the lower respiratory tract in CAP ?
inhalation
aspiration (foreign object enters via aspiration)
haematogenous (less common)
direct (penetrating wound from outside)
Outline the pathophysiology of pneumonia
invasion and overgrowth of lung parenchyma
overwhelms host defences
intraalveolar exudates
reduces ventilatory capacity (V/Q) mismatch
What are the components of the fluid that fill the alveoli in pneumonia?
pus (dead cells)
mucous
blood
-contains everything that is trying to kill off the infective agent
Briefly compare and contrast lobar vs bronchial pneumonia
lobar pneumonia tends to affect one or more lobes of the lungs
whilst
bronchial pneumonia affects patches throughout the lung
What measures can we take to prevent CAP?
smoking cessation
hygiene
vaccination
- pneumococcal polysaccharide vaccine for >65 years
- pneumococcal conjugate vaccine for infants
- annual flu vaccine for at risk groups
What is V/Q (ventilation/perfusion) mismatch? Describe the V/Q observed in pneumonia
this is when part of the lung receives oxygen without blood flow or receives blood flow but no oxygen
in pneumonia, ventilation is affected as the alveoli is filled with fluid and thus not being aerated whilst perfusion remains okay
What is the presentation of CAP?
productive cough- can be different colours
pyrexia (fever)
dyspnoea
pleuritic pain (lung presses against the visceral pleura)
abnormal auscultation (abnormal breath sounds, presence of cackling sounds)
confusion- based on lack of oxygen
dull percussion- this is due to consolidation (fluid)
arthralgia (joint pain)
How can exercise help relieve symptoms of COPD/pneumonia ?
exercise can get the mucous in the bronchi moving
What are the clinical investigations for diagnosing CAP?
history and examination
bloods (urea&electrolytes, c-reactive protein, FBC)
arterial blood gas
chest Xray
blood cultures
sputum cultures- can take a long while to grow
CRP is a marker of ____________.
inflammation
What is the CURB-65 score ?
it is a severity score for CAP
Confusion (new onset) - oxygen lack
Urea- >7mmol/l
Respiratory rate >30
Blood pressures <90mmHg (s), <60mmHg (d)
age> 65 years
1 point is assigned to each of the components of the CRUB-65 scores (5 possible points)
A higher CURB-65 score increases the ______________.
mortality
How would you manage a patient with a CURB-65 score of 0-1?
treat as an outpatient
How would you manage a patient with a CURB-65 score of 2?
either admit or monitor closely as an outpatient
How would you manage a patient with a CURB-65 score of 3-5?
requires hospitalisation with consideration of ITU
What is the management of CAP?
ABCD resuscitation
antibiotics (IV/ oral) according to local guidelines
outpatient vs inpatient treatment
+/- oxygen
+/- fluids
What is tuberculosis?
This is an infectious disease that is caused by mycobacterium tuberculosis
In many cases of tuberculosis, it remains ___________ before it progresses to ___________.
dormant
active tuberculosis
Many cases of tuberculosis involves the lungs (communicable), list some other organs that can be affected by the tuberculosis causing bacteria
lymph nodes
cns
Liver
bone
genitourinary tract
gastrointestinal tract- TB affects the terminal ileum (crohns disease which can occur anywhere in the GI tract, particularly affects the terminal ileum)
What situations can aid the progression of dormant to active TB?
immunocompromised
steroids
Briefly describe the pathogenesis for tuberculosis
inhalation of infected droplets- deposition in the alveoli
M tuberculosis is engulfed by macrophages
They then multiply within macrophages
Proliferating pathogen kills the macrophages then triggering the immune response
(Type IV hypersensitivity reaction- cell mediated reaction)
granuloma formation
there are no effective attempts to get rid of the bug hence it ends up consuming the lung
What are the potential outcomes of tuberculosis infection?
clearance
persistent latent infection (granuloma) - an incomplete attempt to clear the infection
progression to primary disease
What is the most common type of granuloma present in tuberculosis?
caseous granuloma
caseous granuloma is a collection of macrophages due to inflammation
What is the presentation of tuberculosis?
cough
haemoptysis - coughing up blood
night sweats
risk factors
pyrexia
anorexia
weight loss
malaise
chest pain
Night sweats are most common in the following conditions…
malaria
tuberculosis
lymphoma
What are the risk factors of tuberculosis?
exposure to infection
birth in endemic country
HIV
Immunosuppressive meds (trigger active TB)
malignancy (which may cause immunosuppression?)
IV drug use
malnutrition
alcoholism
diabetes
age
smoking
low socio economic status
Extrapulmonary presentations of tuberculosis are most common in what type of patients ?
immunocompromised patients (e.g. >50% HIV cases)
children
What organs are affected by extrapulmonary tuberculosis?
pleura
CNS
lymphatics
Scrofula (cervical tuberculous lymphadenitis)- in the neck
genitourinary system- lymph nodes are affected in this area
bones/joints- joints of the spine collapse
Potts disease
Why does tuberculosis usually affect the upper apices (lobes) of the lungs?
Mycobacterium tuberculosis is a strict aerobe!
air tends to rise- relatively higher oxygen tension in upper lobes
There is also delayed lymphatic drainage in upper lobes of the lungs
What clinical investigations can be carried out to aid diagnosis of tuberculosis?
chest Xray
sputum culture (acid fast bacilli)
tuberculin skin test (mantoux test)- to see if latent TB is present
FBC
lymph node biopsy
pleural fluid ta
long bone xray
CSF
urinalysis
What is the management for latent TB?
evaluate close relatives
isoniazid for 6-9 months, rifampicin for 4 months
pyroxidine for immunocompromised patients
RIP- rimfampicin, isoniazid, pyroxidine
What is an important drug interaction of rimfapicin?
increases clearance of warfarin and thus reduces the anti-coagulant effect
What is the management of active TB?
initial phase therapy
continuation therapy
many treatment regimens
HIV treatments
+/- Surgery
What are the dental considerations for latent TB?
normal infection control precautions
What are the dental considerations for active TB?
defer non-urgent treatment until non-infectious
if not already refer for medical care
urgent dental care should be provided in a facility that has the capacity for airborne infection isolation
What are the two main types of lung cancer?
Metastatic lung cancer- lots of cancers metastasise to the lungs
Primary lung cancer
What are the types of primary lung cancer?
small cell (12%)
non small cell (87%)- adenocarcinoma, squamous cell carcinoma, large cell carcinoma
What is the presentation of lung cancer?
cough
dyspnoea
haemoptysis (shared presentation with tuberculosis)
chest/shoulder pain
weight loss
hoarseness of voice
confusion
dysphagia
bone pain/fractures
Haemoptysis
weight loss
hoarseness of voice
clubbing is a sign of lung cancer in the absence of thyroid disease or other conditions
What are the risk factors for lung cancer?
smoking
environmental exposure
COPD
family history
age
asbestos exposure
What are the investigations for lung cancer diagnosis?
chest XR
CT of neck, thorax, abdominal, pelvis (to look for other primary sites)
endoscopy and biopsy
FBC, urea and electrolytes
Outline the management for lung cancer
Discussion in multi-disciplinary team
Management is dependent on type, TNM staging and fitness for surgery
-operable Vs non operable
-resection
-chemotherapy
-radiotherapy
-palliative care
Give possible options for an operable type of lung cancer
Wedge resection (small section of a lobe)
Segmentectomy- segment of one lobe removed
Lobectomy- an entire lobe removed
Pneumonectomy (removal of an entire lung or a large portion of a lung)
What are some dental considerations for lung cancer patients
chemotherapy- affects bone marrow (fast replicating) cells- bleeding risk
avoid non essential dental work
non invasive dental treatment can be provided in primary care
immunocompromised (white cells in bone marrow due to chemotherapy)- risk of infection
blood test in the last 48 hours if urgent treatment is required; RBC (white cells, platelets etc can be monitored)
