Tuberculosis

WHO had been particularly keen on the use of the test and in 2010 said that:

“This new test represents a major milestone for global TB diagnosis and care. It also represents new hope for the millions of people who are at the highest risk of TB and drug resistant disease.”

The main advantages of the test are, for diagnosis, reliability when compared to sputum microscopy and the speed of getting the result when compared with the culture test.

For diagnosis of TB, although sputum microscopy is both quick and cheap, it is often unreliable. It is particularly unreliable when people are HIV positive.

Although culture gives a definitive diagnosis, to get the result usually takes weeks rather than the hours of the Genexpert test.

The main advantage in respect of identifying rifampicin resistance, is again the matter of speed. Normally to get any drug resistance result takes weeks rather than hours.

The shelf life of the cartridges is only 18 months

A very stable electricity supply is required

The instrument needs to be recalibrated annually

The cost of the test

The temperature ceiling is critical

It involves preventing the spread of TB risk factors and lifestyles that may predispose to its spread especially in developing countries

Therefore the need to preserve and encourage the lifestyles that contain its spread in the community

Since the risk factors of TB is multifactorial, the approach to prevention should be multifactorial and aimed at controlling as many risk factors as possible

• Regulation on the good housing
• Regulation on alcohol sale that lead to reduced immunity
• Chimney at TB clinics and TB hospital for prompt sucking of expelled air.

Improvement in housing (good ventilation, avoidance of overcrowding) will reduce the chances of air-borne infections.

Health education should be directed at producing better personal habits with regard to spitting and coughing.

Good nutrition enhances host immunity

Specific Protection

Three measures are available:

1. Active immunization with BCG (Bacille Calmette Guerin);
2. Chemoprophylaxis; and
3. Control of animal tuberculosis

1. Active Immunization

BCG vaccination

• This vaccine contains live attenuated tubercle bacilli of the bovine strain.
• It may be administered intradermally by syringe and needle or by the multiple-puncture technique.
• It confers significant but not absolute immunity; in particular, it protects against the disseminated miliary lesions of tuberculosis and tuberculous meningitis.

Immunization strategy

• BCG vaccination may be used selectively in tuberculin-negative persons who are at high risk, for example close contacts, doctors, nurses and hospital ward attendants.
• A strain of BCG that is resistant to isoniazid has been developed; this can be used in vaccinating tuberculosis contacts who require immediate protection with isoniazid.
• BCG may also be used more widely in immunizing tuberculin-negative persons, especially children, in the community
• In some developing countries where preliminary tuberculin testing may significantly reduce coverage, BCG may be administered in mass campaigns without tuberculin tests
• The disadvantage of this method of ‘direct BCG vaccination’ is that those who are tuberculin-positive are likely to show more severe local reactions at the site of vaccination.
• BCG vaccination of the new-born is widely practiced in the tropics.
• Overall, the evidence suggests that it confers considerable protection against tuberculosis in infants and young children.
• The strategy introduced recently in Expanded Immunization Programmes, is to give BCG vaccination a few months after birth. The implications of this different timing have yet to be assessed

Disadvantages

Various complications have been encountered in the use of BCG. These may be:

• Local – chronic ulceration, discharge, abscess formation and keloids;
• Regional – adenitis which may or may not suppurate or form sinuses;
• Disseminated – a rare complication.

The protective efficacy of BCG vaccine has varied considerably in different countries.

Chemoprophylaxis

Isoniazid has proved an effective prophylactic agent in preventing infection and progression of infection to severe disease.

Treatment with isoniazid for 1 year is recommended for the following groups:

• Close contacts of patients
• Persons who have converted from tuberculin negative to tuberculin-positive in the previous year
• Children under 3 years who/ are tuberculin positive from naturally acquired infection

Control of bovine tuberculosis

• The ideal is to maintain herds that are free of tuberculosis.
• Infected animals can be identified by the tuberculin skin test and eliminated.
• Milk, especially from herds that are not certified tuberculosis free, should be pasteurized
• After slaughter, carcasses of cattle should be examined for signs of tuberculosis.
• Such infected meat should be condemned

Case-finding operations should aim at identifying active cases at an early stage of the disease. This would depend on maintaining a high index of suspicion in clinical practice and carrying out routine screening, especially of high-risk groups.

Screening

Screening methods include tuberculin testing,

Sputum and chest X-ray examination

1. Tuberculin test. The interpretation of the tuberculin test would depend on local epidemiological factors
2. Sputum. Microscopic examination of Ziehl–Neelsen stained smears of sputum is a simple cheap screening technique which is particularly useful in rural areas of developing countries where resources are limited.
3. Chest X-ray. Mass miniature radiography (MMR) has been widely applied and has been particularly valuable in detecting pre-symptomatic disease, but it is:
• Relatively expensive to establish and run;
• It requires highly trained personnel; and
• It has little specificity, showing many lesions that are definitely non-tuberculous or of doubtful origin. WHO no longer recommends its routine use for screening

High-risk and special groups that should be screened include:

• Contacts of tuberculous patients (both household contacts and workmates);
• Persons who have cough persisting for 3 weeks or more;
• Workers in hospitals and sanatoria;
• Teachers, food handlers and other persons who come into contact with the public;
• Immigrants from high-incidence regions;
• Residents in common lodging houses.

Drug Treatment

WHO recommends the short course directly observed therapy (DOTS).

This consists of 2 months of isoniazid, rifampicin, pyrazanimide and ethambutol given daily, followed by 4 months of isoniazid and rifampicin given thrice weekly

As part of the DOTS strategy, health workers counsel and observe their patients swallowing each dose, and the health service monitors the patients’ progress until each is cured

Political and financial commitments and a dependable drug supply are essential parts of the DOTS strategy

Despite the fact that DOTS is very cost-effective ($20 for 6 months of medicines), not all endemic countries have adopted it yet

In terms of disability adjusted life years (DALYs), treatment of smear positive cases of TB with DOTS works out at $3 per DALY saved – a very effective intervention.

The DOTS strategy is being reviewed and may be modified in the future.

An urgent need for new effective anti-tuberculous drugs exists

Modified DOTS Strategy

Discuss with each new patient:

• The specific treatment needed (daily directly observed treatment for 2 or 3 months in the initial phase)
• Whether the patient can come to the health facility each day. Note: If the patient’s treatment regimen includes a streptomycin injection, a trained health worker must observe the treatment and give the injection
• Trained health workers and the supplies for giving sterile injections are usually available only at a health facility
• If the patient will come to the health facility each day, a health worker at the health facility will directly observe treatment
• If it is not convenient for the patient to come to the health facility each day, explain to the patient that a community TB treatment supporter, that is, a person from outside the health facility, may provide directly observed treatment
• Explain that a community TB treatment supporter may observe treatment in the community including the patient’s home or workplace.
• If the patient needs a community TB treatment supporter, discuss possible locations and individuals

Prepare the patient for self-management

• This treatment supporter will keep the patient’s drugs, observe as the patient swallows the treatment each day, and mark the necessary records
• Use the 5 A’s to prepare patients for adherence:
1. Assess
2. Advise
3. Agree
4. Assist and
5. Arrange
• Explain the importance of self-management with the IMAI Flipchart for Patient Education

Select a treatment supporter

The treatment supporter should be someone who:

• Is chosen by or acceptable to the patient
• Is a respected and trusted person in the community
• Has accepted the patient’s illness
• Is committed to support the patient for a long time
• Has gained the patient’s trust over time
• Is available to be educated
• Is available often especially in the first months of therapy
• Is somebody who will treat all information as confidential

Different types of treatment supporters and their proximity to the patient

• A treatment supporter may be a community member very close to the patient, such as a family member or friend.
• Or the treatment supporter could be someone who already has an established relationship with the health services—already paid for or have responsibility for health-related peer support
• Talk with the patient about the patient’s life, how the patient is feeling and any concerns or problems that the patient may be experiencing. Re-inforce key messages on prevention activities

Be a patient advocate

• Be able to identify any problems that the patient is having and should notify the health facility immediately (For example: health problems, problems taking medications, housing problems, no food available, problems in with family members or partners)

Patient counseling and education

• Explain the importance of adherence and regular visits to the health facility; provide information about prevention, treatment, positive living.

Monitor for symptoms of new side effects/opportunistic infections and refer to the health facility when needed

• This should be not only for patients but also family members of the patient and even other community members encountered by the treatment supporter.

Adherence support

• Should be tailored to the individual patient’s circumstances and be based on the patient’s needs and mutual respect between the patient and the provider. Measures may include direct observation of ingestion (directly observed therapy—DOT) of both TB and ARV medication.
• Agree on a time and place to meet the patient. Do not make the patient wait.
• Give the patient the drugs at each appointment according to the schedule. Check the drugs to be sure that they are correct. Watch the patient swallow all the drugs
• Record on the treatment card each time the patient takes the drugs.
• Be aware of possible side-effects. Have the patient eat food with the tablets if needed to reduce nausea. Refer the patient to the health facility if the side-effects continue.

Encourage the patient to continue coming for treatment.

• Extra or special adherence support for MDR TB+/-HIV
• Additional adherence support is often needed during TB-ART co-treatment because of the extra pill burden and more adverse effects Immune reconstitution syndrome (worsening of TB signs and symptoms) might happen, and this can be uncomfortable and confusing for the patient.

Community:

• Trained TB community treatment supporters can be trained to support the patient on ART as well.

Good coordination between TB and HIV programme:

• Share treatment supporters.

Specific counseling on benefits of ART and adherence barriers

• Extra or special adherence support for MDR TB+/-HIV
• Food supplementation—monthly food stipend of beans and rice or other sources of protein
• Transportation costs for health centre visits—monthly visits to the health clinic can be a financial burden to individuals and can deter them from coming to see the doctor or nurse.
• Additional education—about TB, HIV and the importance of taking medications regularly and having monthly clinic visits. Peer support groups—People facing similar life situations, especially adverse or unpleasant situations, often find comfort, support and strength in being together with others who are in the same or similar situations. These may be peer-led groups or therapeutic groups led by a professional or paraprofessional

Apart from early diagnosis and effective drug treatment, steps should be taken to limit the physical, mental and social disability associated with the disease.

The physical aspect may require active physiotherapy, for example breathing exercises, appropriate body exercises and support for diseased bones and joints.

The mental disability may be limited by suitable diversional or occupational therapy and by simple reassurance or more expert psychotherapy

Rehabilitation

This should, as always, commence from the beginning of the treatment of the patient. Most patients recover sufficiently well to return to their former occupation.

Where chronic physical disability is unavoidable, the patient can be retrained for alternative employment

Surveillance of Tuberculosis

For effective control of tuberculosis, there should be a surveillance system to collect, evaluate and analyse all pertinent data, and use such knowledge to plan and evaluate the control programme.

The sources of data will include:

• Notification of cases
• Investigation of contacts, post-mortem reports;
• Special surveys – tuberculin, sputum, chest x-ray;
• Laboratory reports on isolation of organisms
• Including the pattern of drug sensitivity
• Records of BCG immunization – routine and mass programmes;
• Housing, especially data about overcrowding;
• Data about tuberculosis in cattle;
• Utilization of antituberculous drugs

Stop TB Initiative

Its main thrust is to promote the use of the cost effective Directly Observed Treatment, Short Course (DOTS);

• Increase political commitment,
• Guarantee adequate financing and human resources;
• Improve organization and management capacity
• Ensure uninterrupted supplies of high-quality anti-TB drugs.

A ministerial conference for 20 of the world’s highest TB burden countries was held in Amsterdam in March 2000