Pneumonia, Tuberculosis and Lung cancer

Question 1

What is pneumonia ?

Answer 1

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

Question 2

List some causes of pneumonia

Answer 2

atypical bacteria
legionella
severe acute respiratory syndrome
acute aspiration (dental elements)- aspiration pneumonia
aspergillosis
community acquired
hospital acquired
pneumocystis jirovecii

Question 3

What is community acquired pneumonia?

Answer 3

this is pneumonia that is acquired outside of healthcare facilities

Question 4

Who is most at risk of community acquired pneumonia?

Answer 4

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

Question 5

How does fluid appear on a chest x-ray ?

Answer 5

radiopaque

Question 6

How does air appear on a chest x-ray?

Answer 6

radiolucent

Question 7

What is the most common causative pathogen of community acquired pneumonia?

Answer 7

streptococcus pneumoniae (30-35%)

Question 8

Name some atypical bacteria that can cause community acquired pneumonia (CAP)

Answer 8

mycoplasma pneumoniae (37%)
chlamydophila pneumoniae (5-15%)
legionella pneumophila (2-6% immunocompromised pts)

Question 9

Viruses are responsible for around 10-30% of community acquired pneumonia. List some viral pathogens that can cause pneumonia

Answer 9

influenza virus A/B
respiratory syncytial virus
adenovirus
rhinobvirus
parainfluenza virus

Question 10

5-13% of community are acquired pneumonia are polymicrobial. True or false

Answer 10

true

Question 11

What are the mechanisms by which pathogens can reach the lower respiratory tract in CAP ?

Answer 11

inhalation
aspiration (foreign object enters via aspiration)
haematogenous (less common)
direct (penetrating wound from outside)

Question 12

Outline the pathophysiology of pneumonia

Answer 12

invasion and overgrowth of lung parenchyma
overwhelms host defences
intraalveolar exudates
reduces ventilatory capacity (V/Q) mismatch

Question 13

What are the components of the fluid that fill the alveoli in pneumonia?

Answer 13

pus (dead cells)
mucous
blood
-contains everything that is trying to kill off the infective agent

Question 14

Briefly compare and contrast lobar vs bronchial pneumonia

Answer 14

lobar pneumonia tends to affect one or more lobes of the lungs

whilst

bronchial pneumonia affects patches throughout the lung

Question 15

What measures can we take to prevent CAP?

Answer 15

smoking cessation
hygiene
vaccination
- pneumococcal polysaccharide vaccine for >65 years
- pneumococcal conjugate vaccine for infants
- annual flu vaccine for at risk groups

Question 16

What is V/Q (ventilation/perfusion) mismatch? Describe the V/Q observed in pneumonia

Answer 16

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

Question 17

What is the presentation of CAP?

Answer 17

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)

Question 18

How can exercise help relieve symptoms of COPD/pneumonia ?

Answer 18

exercise can get the mucous in the bronchi moving

Question 19

What are the clinical investigations for diagnosing CAP?

Answer 19

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

Question 20

CRP is a marker of ____________.

Answer 20

inflammation

Question 21

What is the CURB-65 score ?

Answer 21

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)

Question 22

A higher CURB-65 score increases the ______________.

Answer 22

mortality

Question 23

How would you manage a patient with a CURB-65 score of 0-1?

Answer 23

treat as an outpatient

Question 24

How would you manage a patient with a CURB-65 score of 2?

Answer 24

either admit or monitor closely as an outpatient

Question 25

How would you manage a patient with a CURB-65 score of 3-5?

Answer 25

requires hospitalisation with consideration of ITU

Question 26

What is the management of CAP?

Answer 26

ABCD resuscitation antibiotics (IV/ oral) according to local guidelines outpatient vs inpatient treatment +/- oxygen +/- fluids

Question 27

What is tuberculosis?

Answer 27

This is an infectious disease that is caused by mycobacterium tuberculosis

Question 28

In many cases of tuberculosis, it remains ___________ before it progresses to ___________.

Answer 28

dormant active tuberculosis

Question 29

Many cases of tuberculosis involves the lungs (communicable), list some other organs that can be affected by the tuberculosis causing bacteria

Answer 29

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)

Question 30

What situations can aid the progression of dormant to active TB?

Answer 30

immunocompromised steroids

Question 31

Briefly describe the pathogenesis for tuberculosis

Answer 31

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

Question 32

What are the potential outcomes of tuberculosis infection?

Answer 32

clearance persistent latent infection (granuloma) - an incomplete attempt to clear the infection progression to primary disease

Question 33

What is the most common type of granuloma present in tuberculosis?

Answer 33

caseous granuloma caseous granuloma is a collection of macrophages due to inflammation

Question 34

What is the presentation of tuberculosis?

Answer 34

cough haemoptysis - coughing up blood night sweats risk factors pyrexia anorexia weight loss malaise chest pain

Question 35

Night sweats are most common in the following conditions...

Answer 35

malaria tuberculosis lymphoma

Question 36

What are the risk factors of tuberculosis?

Answer 36

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

Question 37

Extrapulmonary presentations of tuberculosis are most common in what type of patients ?

Answer 37

immunocompromised patients (e.g. >50% HIV cases) children

Question 38

What organs are affected by extrapulmonary tuberculosis?

Answer 38

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

Question 39

Why does tuberculosis usually affect the upper apices (lobes) of the lungs?

Answer 39

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

Question 40

What clinical investigations can be carried out to aid diagnosis of tuberculosis?

Answer 40

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

Question 41

What is the management for latent TB?

Answer 41

evaluate close relatives isoniazid for 6-9 months, rifampicin for 4 months pyroxidine for immunocompromised patients RIP- rimfampicin, isoniazid, pyroxidine

Question 42

What is an important drug interaction of rimfapicin?

Answer 42

increases clearance of warfarin and thus reduces the anti-coagulant effect

Question 43

What is the management of active TB?

Answer 43

initial phase therapy continuation therapy many treatment regimens HIV treatments +/- Surgery

Question 44

What are the dental considerations for latent TB?

Answer 44

normal infection control precautions

Question 45

What are the dental considerations for active TB?

Answer 45

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

Question 46

What are the two main types of lung cancer?

Answer 46

Metastatic lung cancer- lots of cancers metastasise to the lungs Primary lung cancer

Question 47

What are the types of primary lung cancer?

Answer 47

small cell (12%) non small cell (87%)- adenocarcinoma, squamous cell carcinoma, large cell carcinoma

Question 48

What is the presentation of lung cancer?

Answer 48

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

Question 49

What are the risk factors for lung cancer?

Answer 49

smoking environmental exposure COPD family history age asbestos exposure

Question 50

What are the investigations for lung cancer diagnosis?

Answer 50

chest XR CT of neck, thorax, abdominal, pelvis (to look for other primary sites) endoscopy and biopsy FBC, urea and electrolytes

Question 51

Outline the management for lung cancer

Answer 51

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

Question 52

Give possible options for an operable type of lung cancer

Answer 52

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)

Question 53

What are some dental considerations for lung cancer patients

Answer 53

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)