Tuberculosis

Tuberculosis Done by: Jehad Alqurashi

Supervised by: Prof. Zaiden Abdu Zaiden

Background

Tuberculosis (TB) is an infectious disease that is

caused by a bacterium called Mycobacterium

tuberculosis.

TB primarily affects the lungs, but it can also affect

organs in the central nervous system, lymphatic

system, and circulatory system among others.

There were an estimated 8.7 million cases of TB in

2011 and 1.4 million TB deaths.

Most of the cases were reported from Asia (59%

In Africa (26%).

The Millennium Development Goals set a target

to halt and reverse the incidence of the disease

by 2015.

Global incidence rates have been falling,

although slowly over the past few years in various regions of the world.

Mode of Transmission :

Transmission can only occur from people with active—not

latent—TB.

The probability of transmission from one person to another

depends upon :

The number of infectious droplets expelled by a carrier,

The effectiveness of ventilation,

The duration of exposure,

And the virulence of the M. tuberculosis strain.

The chain of transmission can be broken by isolating

people with active disease and starting effective anti-

tuberculosis therapy.

SIGNS AND SYMPTOMS:

A bad cough that lasts 2 weeks or longer

Weight loss

Coughing up blood

Weakness or fatigue

Intermittent fever and chills

Night sweats

How TB is Diagnosed:

For diagnosing active “recent” TB infection in

addition to symptoms:

AP chest X-ray should be taken appearances

suggestive of TB should lead to further investigation.

Chest Radiograph Abnormalities often seen in

apical or posterior segments of upper lobe or

superior segments of lower lobe.

Arrows points to cavity in patient’s

left upper lobe

Tuberculin test

intradermal injection of PPD “M. tuberculosis antigens (5 TU)

The test is very sensitive for detecting

tuberculosis in healthy individuals if 5 mm

induration is used to define a positive reaction.

Read it after 48-72 h

Positive: induration≥ 10 mm

The left picture is the correct

way to measure Tuberculin skin

test

Acid- Fast Bacilli (AFB) smear &

Culture

A PPD test is always done to show whether the

patient has been infected by the tubercle

bacillus.

To verify the test results, the physician obtains a

sample of sputum or a tissue sample (biopsy) for

culture.

Three to five sputum samples should be taken

early in the morning.

Culturing M. tuberculosis is useful for diagnosis

because the bacillus has certain distinctive

characteristics. Unlike many other types of bacteria, mycobacteria can retain certain dyes

even when exposed to acid.

This so-called acid-fast property is characteristic

of the tubercle bacillus.

Quantiferon-TB test: The IFN-γ by T-cells into the plasma is measured by ELISA

to indicatsecreted e the likelihood of TB infection .

Different studies demonstrated that the QuantiFERON-TB test was comparable to TST in its ability to detect latent TB infection. also showed that the QuantiFERON-TB test was less affected by BCG vaccination.

QuantiFERON-TB was approved by the Food and Drug Administration (FDA) of the United States (US) in 2001.

In 2003, the US Centers for Disease Control and Prevention released guidelines for using the QuantiFERON®-TB Test in the diagnosis of latent M. tuberculosis infection.

Patient will be treated with the standard

treatment of four drugs :

Isonicotinylhydrazine (INH),

Rifampicin.

Ethambutol,

Pyrazinamide) for an initial 2 months.

Followed by a combination of INH and rifampicin

for another 4 months.

Patients should be treated under DOTS.

DOTS (directly observed treatment, short-

course), is the name given to the tuberculosis

control strategy recommended by the World

Health Organization.

According to WHO, “The most cost-effective way

to stop the spread of TB in communities with a

high incidence is by curing it.

The best curative method for TB is known as DOTS.”

DOTS has five components:

1) Government commitment (including political will at all

levels, and establishment of a centralized and

prioritized system of TB monitoring, recording and

training).

2) Case detection by sputum smear microscopy.

3) Standardized treatment regimen directly of six to eight

months observed by a healthcare worker or

community health worker for at least the first two

months.

4) A regular, uninterrupted drug supply.

5) A standardized recording and reporting system that

allows assessment of treatment results.

METHODS OF CONTROLLING TB:

1. Isolation: Immediate isolation of people who have

confirmed or suspected cases of tuberculosis can help stop the spread of the disease.

Patients do not need to be kept isolated for

longer than two weeks.

Isolation should last until the patient responds

to treatment and is not coughing.

2.Respiratory Protection: This type of protection should be

worn by a healthcare worker who

enters a tuberculosis patients room.

This will protect them from contracting

tuberculosis.

The respirator should be a N-95 disposable

particulate respirator (PR) that filters inhaled air.

A surgical mask is not adequate protection to

protect someone from contracting tuberculosis.

3. Training

Educating healthcare workers, and anyone that

might come into contact with a tuberculosis patient,

is the first step in helping to prevent the spread of

tuberculosis.

They should know the symptoms of tuberculosis

infection, how it is spread, what the difference is

between infection and disease, how it is diagnosed,

how to prevent spread, and treatment for tuberculosis infection and active disease.

4. Ventilation

One method of ventilation is dilution and removal of

contaminants in the air.

An exhaust system should vent air outside the building.

Air should flow into a tuberculosis patients room from

the areas nearby, creating a low or negative pressure

in the patients room.

In hospitals that use recirculated air, HEPA filters should

be installed the ventilation system. The filters remove

most of the tuberculosis contaminants in the air.

Global efforts to control TB were reinvigorated in

1991, when a World Health Assembly (WHA)

resolution recognized TB as a major global public health problem.

Two targets for TB control were established as part

of this resolution:

Detection of 70% of new smear- positive cases,

Cure of 85% of such cases, by the year 2000.

Stop TB Program:

WHO’s Stop TB Strategy aims to reach all patients

and achieve the target under Millennium

Development Goal Six (MDG6):

To reduce by 2015 the prevalence of and deaths due to

TB by 50% relative to 1990 and reverse the trend in

incidence.

The strategy emphasizes the need for proper health

systems and the importance of effective primary health

care to address the TB epidemic.

By 2005, detect at least 70% of new sputum smear-positive TB cases and cure at least 85% of these cases.

By 2015, reduce TB prevalence and death rates by 50% relative to 1990.

By 2015: the global burden of TB disease (deaths and prevalence) will be reduced by 50% relative to 1990 levels.

By 2050, eliminate TB as a public health problem (<1 case per million population).

By 2050: The global incidence of TB disease will be less than 1 per million population. (Elimination of TB as a global public health problem.)

TB in Kingdom of Saudi

Arabia

According to Dr.Ibrahim Al-Orinay’s study which titled : Tuberculosis incidence Trends in Saudi Arabia over 20 years: 1990-2010

There were a total of 64,345 TB cases reported to the Ministry of Health during 1991-2010.

Of these, there were 46,827 (73%) pulmonary TB cases

17,518 (27%) extra-pulmonary TB.

There were 33,468 (52%) Saudi patients and 30,837 (48%) non-Saudis.

The majority (62%) were males.

Over 70% of the cases were reported from the Central and Makkah regions. These two regions have 52% of the population of the kingdom.

The annual incidence of TB ranged between 14

and 17/100,000 over the study period.

Saudis had an incidence between 8.6 and

12.2/100,000 while non-Saudis had an incidence of 24.3-32.3/100,000.

TB incidence showed a rising trend over the first

10 years of the study period.

Annual TB patient numbers and

incidence rate/100,000 in Saudi Arabia

(1990-2010)

Tuberculosis incidence rates/100,000

by age group in Saudi Arabia (1990-

2010)

Tuberculosis incidence rates and

trend in Saudi Arabia (1990-2010)

Tuberculosis incidence rates and trend

for Saudi population by region (1990-2010)

The study concluded the

following:

The NTP had an ambitious goal to reduce the

incidence of TB to 1/100,000 by the year 2010.

This goal unfortunately could not be achieved.

Since 1992, the incidence showed a rising trend that peaked in 1999, and then it started to fall but

only slightly. Foreign population had 2-3 times

higher incidence than Saudi nationals.

The majority of Non-Saudis came from countries

with high burden of TB such as India, Pakistan,

Bangladesh, Indonesia, and Yemen.

Most of them are unskilled workers that tend to

live in crowded housing conditions with poor

nutrition and stressful work.

TB incidence for Non-Saudis showed a falling

trend over the last 10 years while the trend for

Saudis remained stationary.

In the year 2000, the NTP started to implement a strategy of DOTS to all regions in the Kingdom.

This may partially explain the falling overall trend

among non-Saudis over the last decade.

For Saudis, the trend showed a significant rise between 1995 and 2010. It was not affected by

the implementation of DOTS. The absence of an

effect on Saudis trend is difficult to explain.

As the rise in trend was mainly in the Central and

Makkah regions, it may be related to the higher

proportion of Non-Saudis in urban areas of these

regions.

Globally, TB incidence trends showed variations

among countries and regions of the world. In some

areas, the rates have stabilized while in others, they

continue to decline slowly.

Current Situation In Medina:

In 2011 the newly diagnosed cases reported were 200.

In 2012 the newly diagnosed cases reported

were 180.

In 2013 the newly diagnosed cases reported

were 141.

39.72%(56)

60.28%(85)

Case Distribution According to

Nationality in 2013

Saudi

Non Saudi

65.25%

34.75%

Case distribution according to sex

Male Female

References:

World Health organization. WHO Report 2012: Global

Tuberculosis Control; 2012.

Dye C, Maher D, Weil D, Espinal M, Raviglsone M.

Targets for global tuberculosis control. Int J Tuberc

Lung Dis 2006;10:460-2.

Al-Kahtani NH, Al-Jeffri MH. Manual of the National TB

Control Program. Ministry of Health; 2003.

MOH, KSA, Annual statistical report 2011 (Arabic-

English). Available from:

http://www.moh.gov.sa/Ministry/MediaCenter/News/

Documents/healthybook.pdf