TB: An Eminently Curable Enemy [Archives:2001/09/Health]

Dr. Omar Shek
Al-Amoudi
Specialist in Ftiziatria
Th. Surgeons
Ministry of Health
Department of Medical Services
Tuberculosis never went away, and all doctors, particularly those working with at-risk populations, should have a high index of suspicion. TB was once the curse of the Victorian child and young adults, many of whom where cut off in their prime by “consumption.” People from all social classes were sent to Sanatoria for long periods for treatment but many still died. Thoracic surgeons performed a variety of operations, most of which had uncertain value.
However, the incidence of TB in the Yemen had begun to fall – before the use of anti TB drugs, and the improvement was partially due to improving living conditions and nutrition. By the time both BCG vaccination and effective TB drug therapy were in place (1950) the decline was accelerating rapidly. NTP Yemen Reported between the mid 1990 and 1994s notification rates for TB in the Yemen: ARI is 0.9% but I suspected it must be more, and we must check the Yemeni people to confirm the degree of TB-killer of the poor, homeless and immunocompromised.
In Yemen, and particularly in the developing countries, TB has remained an enormous problem. It is still the largest cause of death in adults from an infectious disease. NTP confirmed as death rate in Yemen 15 per 100.000 of population smear + 45 cases per 100.000 population.
TB is eminently curable if adequately managed. Patients often improve quickly and are very grateful for their return to health. TB is not therefore, a historical curiosity, it is a real threat to our patients and a challenge to our clinical skill.
When should the doctor be suspicious about TB?
Classic symptoms of pulmonary TB are cough, malaise, weight loss, haemoptysis and night sweat. However, a patient may only have a few of these, or even none. Other clues may be found in the history, particularly the social review. Even common, everyday complaints, such as chest infections, backache or dysuria, should ring alarm bells in a GPs mind. The GP should be particularly concerned if such complaints are chronic and associated with systemic symptoms, such as fever or weight loss or if they occur in high risk individuals (for example, TB contacts and ethnic group with a high incidence). Remember that sputum, urine, pus any tissue sent for analysis does not automatically get tested for TB-this needs to be specifically requested.
–ray request forms should also indicate a suspicion of infection, including those for skeletal films, such as spinal X-ray. When in doubt, refer earlier rather than later for specialist advice. Tragedies can occur when this does not happen.
The Department of health recommends that treatment of TB, regardless of the organ involved, should be supervised by a hospital physician with a special interest in the disease.
This is normally a respiratory or infectious disease. Where organs other than the lungs are involved, shared specialist care- for instance, with neuro-surgeons, gastroenterologist and urologist-is appropriate.
Despite this need for specialist input, the GP still has an important role. A complex drug regime needs to be initiated and maintained for at least six months, and close communication and team-work between the GP, patient, TB specialist and TB nurse/health visitor is therefore vital. Once the diagnosis is established, the GP should consider the following questions:
1.Is my patient getting the right specialist advice?
Drug therapy supervised by a non TB specialist has been shown to increase morbidity, mortality, relapse rates and the emergence of drug resistance MDR (multi-drug resistance).
2.Is my patient getting the drugs?
Ensure that prescribing responsibilities are clearly defined between you and the specialist if you are prescribing often enough. If not, warn the specialist.
In some cases, three-time a week directly-observed therapy (DOT) can be given, either at home, in the clinic or in the ward. Occasionally, it will be necessary to admit persistently poor compilers for hospital for some or all of their treatment.
3.Am I watching for side-effects?
Drug-induced hepatitis can be caused by most kinds of antituberculous medication. So regular liver function test must be performed in the TB clinic, particularly in the first six weeks of treatment.
Despite this, serious reactions still develop-vigilance by the GP is very important.
Ocular neuritis can occur with ethambutol, so a baseline ophthalmological review should be organized by the specialist at the beginning of treatment. Patients will be told to report any changes in their vision, and the GP should remind them to do this. Rashes can develop with most drugs, and arthralgia is particularly common with pirazinamide. Most reactions are transient, but in the event of a sever reactions, all the drugs should be stopped and specialist advice sought immediately. Stopping one or two drugs, particularly for long period, can lead to drug-resistance.
4.Other important issues:
Isolation of patients – with ‘open’ or smear-positive disease- that is, TB bacilli seen on microscopy of sputum smears- should probably be isolated in hospital for the first two weeks of treatment, particularly if there are young children at home. However, most patients can start their tablets as out patients, as long as their liver function is monitored.
5.Notification and contact tracing:
It is an important requirement that all cases of TB are reported to the local consultant in communicable disease control. While this is normally carried out by the hospital, a check by the GP to confirm that this has occurred is a valuable ‘safety net.’ Notification automatically leads to contact tracing. Contacts at significant risk are largely confined to family and other house-hold members, although worried acquaintances may often visit their GP for advice and reassurance. Unless they are in close daily association with the patient, the latter group are unlikely to be at risk. Some individuals may still require referral to a special list clinic for CXR and further children under 16 years with reassurance. T. Test CXR-should be considered for preventive therapy H (Izoniazid) for six months or HR (Izoniazid + Rifampicin) for 4 months, tuberculin test maybe seen again at 3 and 19 months. Perhaps the most publicized problem relating to TB in recent years is that of multi-drug resistant organisms, this is more commonly seen in immunocompromised individuals, but is also found in patients who have been inadequately treated with only mono-or double-therapy, or have failed to comply with their treatment regime. Resistance to isoniazid alone is not always a major problem, but therapy should include an additional drug, such as ethambutol. However, multi-drug resistance, that is, resistance to both isoniazid and rifampicin, can lead to the need for complex and expensive drug regimes.
The discovery of a multi-drug-resistant strain is often established many weeks after the original diagnosis has been made, since acid-fast bacilli are slow to grow in culture and it therefore takes time to clarify their sensitivities. Such patients need to be under the care of TB specialists experienced in treating multi-resistant strains, and they must be closely monitored.
Specialist investigations:
The important investigations are sequential sputum samples (sent for microscopy for AAFB (Alcol Acid Fast Bacyl) and culture and CXR.
CXR-will often show a characteristic pattern. If cavitation is present in addition to upper lobe infiltrates, TB is likely and may show with a wide variety of radiographic shadows. Appropriate sputum specimens should be sent for analysis if there is any suspicion of disease. If no sputum is expectorated, further efforts should be made to obtain specimens by such methods as:
1.Induced sputum (using nebulized twice normal saline)
2.Transtracheal Saline injection
3.Bronchoscopy with transbronchial biopsy, and segmental large.
4.Open lung biopsy in obscure or atypical disease
5.Pulmonoscopy
6.Pleural punction (analysis of exudate or transudate)
NB: The Zechl-Neelsen Stain has specificity of over 99% and an overall sensitivity of 55% in Pulmonary TB.
New serological diagnosis – methods used for antigen detection include enzyme-linked immunosorbeassay, competitive inhibition of the binding of monoclonal antibodies.
Specifities of most serological test are high (90-99%) but sensitivities are generally much lower, though sensitivities of up to 90% have been reported in some studies. Antibodies have been detected in pleural fluid and pronchial washing in, CSF. Antibodies or semi-purified extracts of M. Tuberculosis are found in 24-54% of patients.
Tuberculosis epidemiology survey
1.Montoux testing must be performed in a sample survey in all provinces of Yemen. TB is considered to be a common health problem, but in the absence of any comprehensive epidemiological study the extent of the problem remains unknown. Previous tuberculin test survey in some selected populations have shown tuberculin test rates ranging from as low as 1.9% to as high as 70%, and must be considered by a WHO and JAIKA expert committee on tuberculosis to measure the tuberculosis problem in the community, specially in Yemen. Tuberculin skin test- the test involves on intradermal of (PPD) purified protein derivative – either by a needle injection (mantoux test) – and observing the scale of the indurated skin response. PPD in the following dilution is available:
1 in 10.000-10 TU/ml 1 in 1000-1-TU/ml 1 in 100-1000 TU/ml mantoux test – in this test 01 ml of a chosen dilution (1-1000-10 TU) injected intradermally (a bleb must be raised). The diameter of induration in transverse plane of the arm is measured after 48-72 hours and recovered in mm. The area of erythema around the induration of 10mm or more is regarded as positive. If BCG has not been given before, an induration of 15 mm is regarded as positive. If BCG has been given, individuals who are HIV positive- the tuberculin test may be negative (Hypersensitivity response), and does not exclude TB.
Prevention – control programs depend on 3 principles:
A: Identification and treatment of those with disease AAFB
B: Screening of those at risk
C: Protection of the rest of the community by BCG
D: Researches in the community by tuberculin tests:
a) manitou test b) heaf test + flurographia or CXR as hyperdiagnostic.
E: Admission of the patient with BK + and to resolve the socio-economic problems in Yemen.
This is my suggestion for diagnosis, treatment and prevention of tuberculosis in Yemen.

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