T-SPOT.TB test detects early Latent TB bacteria

Latent tuberculosis (also known as LTBI - latent tuberkuloseinfeksjon) is healthy people who carry tuberculosis bacteria in an inactive state. People with latent tuberculosis have no symptoms of the disease and do not feel tired. However, if the immune system is weakened, tuberculosis bacteria will multiply and lead to active tuberculosis.

.

People with latent tuberculosis are people who have had contact with people with tuberculosis. Tuberculosis bacteria spread into the air when people with tuberculosis talk, sneeze and cough, etc. Healthy people will inhale bacteria particles when in contact with sick people. However, a healthy immune system will neutralize bacterial activity and cannot cause disease.

.

People at risk of latent tuberculosis are those who have had close contact with a person with tuberculosis. Or people coming from areas with many people infected with TB such as Asia, Eastern Europe, Latin America, and Africa will be at higher risk.

.

In addition, people who have been vaccinated against tuberculosis still have the possibility of latent tuberculosis infection. Because the BCG tuberculosis vaccine is a vaccine that protects young children against exposure to tuberculosis, or severe forms of tuberculosis, and is effective for about 1 year. In adults, the BCG vaccine does not prevent tuberculosis infection.

.

Latent TB testing is needed for 2 high-risk groups, including:

GROUP IN CLOSE/FREQUENT CONTACT WITH PULMONARY TUBBER PATIENTS

+ Children under 5 years old who have household contact with tuberculosis patients

+ People aged 5 years and older who have household contact with tuberculosis patients

+ Medical staff working in TB prevention units at medical facilities may have TB patients come for examination

+ Prisoners, prison guards, and staff working at prisons and reformatories

.

GROUPS OF PEOPLE WHO HAVE FACTORS THAT INCREASE THE RISK OF DEVELOPING TUBBER INFECTION INTO TUBBER DISEASE

+ People with HIV of all ages

+ Patients with pneumoconiosis

+ Diabetic patients

+ Patients with kidney failure and hemodialysis

+ Organ transplant patients and people preparing for organ transplant

+ Patients regularly treated with immunosuppressive drugs (autoimmune diseases such as lupus, rheumatoid arthritis, psoriasis) and patients treated with biological drugs (anti-TNF)

.

People with latent TB cannot spread it to others. Because bacteria in the body are in an inactive state, they cannot reproduce. The amount of bacteria is small and cannot spread into the air. This is also one of the conditions to identify people with latent tuberculosis.

.

However, people with latent tuberculosis are at risk of contracting tuberculosis if the immune system is weakened. Therefore, if a person with latent TB becomes active TB. At this point, that person will be able to spread the disease to others. Therefore, people with latent tuberculosis should receive preventive treatment to prevent the risk of tuberculosis.

.

In short, latent TB is people who carry TB bacteria in an inactive state, do not show signs of illness, have no symptoms, and do not transmit TB bacteria to others. However, people with latent TB are at risk of developing TB disease when their immune system is weakened. Therefore, these people need to go to a medical facility for advice and effective preventive treatment.

.

T-SPOT.TB is a test belonging to the IGRA group to detect active and latent TB.

.

Testing is the first step in treating patients with latent TB to break the cycle of TB transmission.

.

1. Equipment: Stereo microscope

.
2. Technology: Elispot

.
3. Chemicals: T-SPOT.TB - Oxford Immunotec, UK.

.

4. Samples:
+ Heparin anticoagulated whole blood:
_6 mL: adults and children ≥ 10 years old
_4 mL: children ≥ 2 to < 10 years old
_2 mL: children < 2 years old

.

5. Sensitivity:

Evaluation of 87 samples from individuals with culture-confirmed M. tuberculosis infection, including immunocompromised individuals. Sensitivity reached 98.8% (86/87) (with a confidence level of 95% and specificity of 90.8 – 99.9%)

.

6. Specificity:

Evaluation of 93 samples from individuals at low risk of M. tuberculosis infection through assessment of history and personal information. Specificity reached 100% (93/93) (with 95% confidence, specificity is 95.8 – 100%)

.

7. Time for results: 2 - 3 days from receipt of sample

.