Tuberculosis Team Lecture

Question 1

Why traditionally was sunlight recommended in TB treatment in sanatoriums?

Answer 1

Inc patient VitD - VitD receptors found on monocytes and activated T cells, boost immune function
Direct Sunlight kills TB bacillus within hours - reduce transmission risk.

Question 2

What are the different sites of he body where TB can infect?

Answer 2

Pulmonary (lungs)
Pleural tuberculosis
Lymph nodes
Bones
CNS - TB meningitis
Larynx

Question 3

What types of TB are infectious?

Answer 3

Pulmonary and laryngeal only.

Question 4

What populations are at higher risk of developing TB infections?

Answer 4

Migrant populations
Homeless
Prisoners
Parent/grandparent born in high risk country

Question 5

What are the key signs and symptoms of a TB infection?

Answer 5

Chest pain or pain with breathing or coughing
Loss of appetite
Chills
Unintentional weight loss
Fatigue
Night sweats
Fever
Coughing up blood (late stage 6-9months into infection - shows highly contagious)
Coughing that lasts three weeks or more.

Question 6

How are the symptoms of TB different to pneumonia?

Answer 6

TB longer duration - particularly the cough for 3 weeks or more
TB more systemic effects such as weight loss, night sweats.

Question 7

What are some risk factors for TB?

Answer 7

Born in high-risk country - Philippines, Congo, Papua New Guinea, China
Parents or Grandparents born in high risk country (travel to visit)
Homelessness - crowding, ventilation, alcohol and drug use
Imprisonment
Time in detention centres
Refugee camps
HIV (or any immunosuppressive state, such as DM)
Smoking
Malnutrition
Severe kidney disease. (delayed diagnosis, immunosuppressed, malnutrition)

Question 8

What is the incidence and prevalence of TB globally?

Answer 8

Over 9 million new cases anually
Around 2 million deaths per year
1/3 of the worlds population if infected with latent Mtb
One of the top three killers next to HIV and Malaria.

Question 9

How does the number of TB cases vary across the UK?

Answer 9

Highest in London - over 2,000 - particularly Newham
Then south of england, west midlands, north east/yorkshire/hampshire
Lowest in east of england and east midlands.

Question 10

What is the prevalance of TB in North of Tyne?

Answer 10

Highest in Newcastle Upon Tyne and Middelsborough
Lowest in Gateshead and Northumberland
Rates are increasing rapidly
Has lower rates compared to england overall
More than 70% of TB cases were born outside of the country - most commonly India, Pakistan and Eritrea.
Associated with Black African, Indian and Mixed ethnicity.

Question 11

How important are social risk factors in TB?

Answer 11

22% of UK born cases have a social risk factor.
SRF are more likely to have pulmonary TB (infectious), less likey to complete treatment and more likely to die or be lost to follow up.

Question 12

What is the relationship between HIV testing and TB?

Answer 12

91% of TB patients have a HIV test.
TB tests are also offered to HIV patients
Due to link between immunodeficiency, infection and poor prognosis.

Question 13

What are the key features of latent TB?

Answer 13

TB lives but does not grow inside the body
Asymptomatic
Not infectious
Can re-activate

Question 14

What are the key features of active TB?

Answer 14

Active and grows in the body
Symptomatic
Infectious
Cause death is untreated.

Question 15

What diagnostic tests are needed for active TB?**

Answer 15

CXR
3x morning Sputum Samples

May if necessary use:
Often used if CXR positive but not coughing so unable to get sputum samples.
CT scan
Bronchoscopy/EBUS - take sample for acid fast bacillus smear
FNA/Surgery - take sample for acid fast bacillus smear.

Question 16

What is the Quantiferon TB Gold Blood test?

Answer 16

Is an ELISA based interferon gamma release essay, whole blood is stimulates overnight with TB, INFgamma is measured by ELISA in the morning and quantified, if previous exposure to antigen will increase amount produced. Memory Th1 cells produce INFgamma
Requires patient blood sample.
Cannot distinguish between latent and active TB

Question 17

What is the LTBI programme?
How was it affected by covid?

Answer 17

Programme to test and treat all newly arrived migrants in England, from high risk TB countries aged between 16-35yrs.
Stopped in April 2020, is now rerunning, but thought to contribute to rise in TB cases from 2020 onwards.

Question 18

What is meant by primary tuberculosis?

Answer 18

The infection of an individual who has not previously been infected
Occurs usually within first 2 years after exposure
Most common in children.

Question 19

What is secondary tuberculosis?

Answer 19

The infection of an individual who has been infected in the past, and this is a flare up (reactivation) of that latent TB
Often occurs due to factors such as reduced immunity, poor nutritional status, alcoholism, drug use or advancing age.
Small percentage may also be caused by reinfection.

Question 20

What is meant by latent, cavity and military tuberculosis?
**

Answer 20

Latent - in granuloma, alive but not replicating.
Cavitary TB - a pathological gas filled space in the lung parenchyma or wall, caused by M.Tb caesating granuloma eroding into airway
Miliary TB - dissemintated form of TB, blood spread through lungs and body, multiple gramulomas throughout lung parenchyma, classified as pulmonary and extra-pulmonary TB.

Question 21

What are the key sides effects from anti-TB drugs?

Answer 21

Rifampicin - jaundice
Ethambutol hydrochloride - colour blind, gout,
Pyrazinamide - gout, liver effects
Isoniazid - peripheral neuropathy, hepatitis, psychosis.
Pyridoxine - peripheral neuritis.

Question 22

What is the role of TB clinical team?

Answer 22

Active TB case findins
Contact tracing
Direct Observed therapy
Education and training for health professionals
Input local and national decision making with UKHSA
Patient and Family Support throughout treatment.

Question 23

What is shown on the x-ray?

Answer 23

TB - areas of black with white surrounding rim
May have areas of opacity which indicates calcification - healing of granulomas
Tend to be thin individual/low weight.

Question 24

What is the guidance on contact tracing in TB?

Answer 24

Investigate all people in contact with pulmonary or extra pulmonary TB to identify primary source of infection
In asymptomatic cotacts younger than 65yrs consider testing for latent TN.
Consider treatment for latent infection or BCG if previously unvaccinated, contact of smera positive pulmonary or laryngeal TB, mantoux negative/IGRA negative.

Question 25

What method of testing is used in contracting tracing in TB?

Answer 25

Mantoux for children (greater than 5mm is positive)
IGRA for all ages
CXR if either are positive.

Question 26

What is direct observed therapy in TB?

Answer 26

Observe patient taking medication, check mouth afterwards to ensure swallowed
Stratergy to assure TB patients adhere to and complete treatment
This reduces the risk of drug resistance, relapse or reactivation.
Improves patient outcomes
Allow to monitor side effects and response to therapy.
Ensures continuous treatment
If not complying can be held indefinitely in isolation under public health act.

Question 27

What are the risks of infection of TB when exposed?

Answer 27

1/1000 chance of infection, 1/10,000 chance of disease from hourly exposure in small air tight space
8 hours contact justifies screening
Risk doubles for smokers, diabetics and males.
Stable HIV more than doubles the risk
HIV with high viral load inc risk by more than 20x.

Question 28

What sort of people do we worry about/might contact during contact tracing?

Answer 28

Household
Other close contact (work etc)
Casual contacts
Schools/universities
HCWs
Patients (next bed etc)
Aircraft passengers (if more than 8hrs flight)

Question 29

What is the BCG vaccine?

Answer 29

A live attenuated vaccine
Not part of NHS schedule
Given when child at risk of coming in contact with TB
Does not last for life but boosters should not be given,not 100% protection.

Question 30

What should HCW working with TB patients do to reduce their risk of infection?

Answer 30

Follow standard Infection Control Precautions
Wear a face mask - FFP3 when patient infected or during aerosol generating procedures or if patient has productive cough and HCW exposed to secretions.

Question 31

How should a suspected TB patient be managed when they come into hospital to reduce infection spread?

Answer 31

Is suspected pulmonary or laryngeal should be given single room accommodation with en-suite sanitary or dedicated sanitary facilities
Should be separated from immunocompromised patients
Smear positive TB patients with clinical or socioeconomic need for admission should by in single room until completed 2 weeks of standard TB treatment and have no risk of rifampicin resistant or have negative rifampicin resistance on nucleis acid amplification test/culture.