Introduction

Tuberculosis (TB) continues to be one of the most important global public health threats. ₁ About one-third of the global population is infected with Mycobacterium tuberculosis and at risk of developing the disease. ₂,₃ More than eight million people develop active TB annually with more than 90% of deaths occurring in the developing world. ₄,₅ Early detection and adequate treatment are critical measures for disease control. The World Health Organization (WHO) has published guidelines for TB control in low income countries.₆,₇ But inadequate case detection and poor treatment continue to be some of the major factors for the increasing burden of TB globally. ₈,₉ Although some studies have documented inadequate TB knowledge and poor compliance with TB treatment guidelines among practicing physicians, ₁₀,₁₁,₁₂,₁₃ such data are lacking in Nigeria. The objective of the study was to assess and document the knowledge of TB and its management practices among medical interns, and their adherence to the National TB Control (NTC) guidelines in Nigeria.

Materials and Methods

The survey was conducted among 118 medical interns between December 2004 and May 2007 at Federal Medical Centre, Ido-Ekiti, Nigeria. This is a tertiary hospital and a referral centre in the southwestern Nigeria. These medical interns, employed at various times in the above hospital, graduated within the previous 12 months before participation in the study. The authors distributed pre-tested questionnaire which were completed under supervision without allowance for discussions or cheatings. The anonymity and confidentiality of the respondents were guaranteed. The questionnaire contained a set of multiple choice questions that assessed knowledge of TB, its methods of diagnosis and management practices. It also had two subjective questions on prescription writing skills for a new case of smear positive pulmonary TB (PTB). The data were entered and analysed using Epi Info 6.04.

Results

Of the 118 interns surveyed, 90 (76.3%) and 28 (23.7%) had graduated from federal- and state-owned universities respectively. At the time of the study, 30 (25.4%), 30 (25.4%), 28 (23.7%) and 30 (25.4%) interns were rotating through the departments of internal medicine, paediatrics,, surgery and obstetrics, and gynaecology respectively.

Knowledge assessment

TB training and exposure during medical school

Diagnosis and follow up of PTB patients

Management of TB in pregnancy and post partum

Patterns of prescription of anti-TB drugs

Directly Observed Therapy, Short Course (DOTS)

About the question on listing the five components of DOTS (sustained political commitment, case detection by sputum smear microscopy, uninterrupted supply of all essential anti-TB drugs, directly observed standardized treatment and efficient information system for monitoring and reporting₁₈), 72 (61.0%) could not list a single component; only 17 (14.4%) could name all the five components; while the remaining respondents (24.6%) were able to list between two to four components.

Figure 1

Table 1: Prescription pattern of anti-TB drugs by respondents for the treatment of a new smear-positive case of PTB with negative HIV serostatus

Discussion

The study revealed gross inadequacies in the knowledge of TB among medical interns. Although the dismal inability of none of the medical interns to correctly state the estimated number of new cases of TB per year is unacceptable, this might not be unconnected with the general absence of accurate data and poor record keeping culture in almost every sphere of the Nigerian state. In a study from Pakistan, poor recognition of the burden of TB and its public health significance was equally identified among medical interns in that country.₁₂ There was an understanding of transmission of TB but poor awareness of definitions of MDR-TB and XDR-TB. Only a paltry 16.7% of the interns could correctly define MDR-TB while none was aware of XDR-TB.

Although XDR-TB is a recent issue and was first reported in late 2005, MDR-TB was discovered in the 1990. ₁₃,₁₉,₂₀,₂₁,₂₂ In this survey, only 16.7% of the interns had performed ZN staining during medical training. This might be unconnected with limited laboratory capacity and dearth of health resources that are hallmarks of teaching health facilities in resource-poor countries. However, unlike the findings from some studies, majority of the interns recognized sputum smear microscopy as the best diagnostic tool for PTB.₁₂,₂₃

The identification of smear positive TB patients and, at least, three consecutive sputum smear examination, are critical points in TB control. One of the damning revelations from the study is in the treatment of TB in pregnancy and postpartum. While less than half of interns did not know that streptomycin should not be used in pregnancy, less than a quarter of them would isolate an infant from the mother with a smear positive PTB to prevent transmission. Most antiTB drugs are safe for use in pregnancy with the exception of streptomycin which is ototoxic to the foetus and should not be used. ₂₄The successful treatment of TB in pregnancy with the recommended standardized regimen is important for successful outcome of the pregnancy. A breastfeeding woman who has TB should receive a full course of TB treatment. ₂₄ All antiTB drugs are compatible with breastfeeding. Timely and properly applied antiTB treatment is the best way to prevent transmission to her baby.

There should be no isolation of the baby from the mother with breastfeeding in the normal way. ₂₄However, the child should be on INH prophylaxis for at least three months beyond the time the mother is considered to be non infectious. ₂₄The gross ignorance about DOTS displayed in this study by medical interns was catastrophic, but subtly showed why this strategy has remained a perpetual failure in this country. Khan et al ₁₂also reported similar finding in their study. Sadly, Nigeria is the most populous African nation and very critical to the control of TB in the continent, but most patients do not have access to DOTS.₂₅ The presence of free anti-TB drugs alone is not synonymous with DOTS.

The essential services needed to control TB were developed and packaged as the DOTS strategy in the early 1990s and has been promoted as a global strategy since the mid-1990s. But despite widespread acceptance of the principles of DOTS, most developing countries have failed to achieve the global target of detecting 70% of infectious cases and curing 85% of those detected.₂₆

There is deficiency in TB education in most Nigerian medical schools and affiliated teaching hospitals. This is made much worse by the absence of effective DOTS clinic in many tertiary health centres including the teaching hospitals. There is an urgent need for massive increase in awareness of DOTS among medical students and practicing medical doctors. First, federal government must enforce the establishment of strict and dedicated DOTS clinic in all tertiary hospitals. Second, medical students must rotate through DOTS clinic and practically participate in all its activities, including performance of ZN staining for sputum smear microscopy.

Lastly, all medical interns must also rotate through a DOTS clinic during their training. The revision of existing medical education curriculum in Nigeria should focus on incorporation of national TB guidelines into TB teachings in schools. The appropriate authority should ensure the circulation and availability of TB guidelines to every practicing medical doctor in the country. This will encourage medical practitioners to inculcate diagnostic and prescription practices that are in accordance with the national TB guidelines.,₂₇,₂₈

Conclusion

The study has shown gross deficiencies in medical education in Nigeria, one of the countries with the largest numbers of TB cases. This is, no doubt, an enormous challenge not only to the effective control of TB in Nigeria, but also in the whole of Africa. There is urgent need to revamp and reform undergraduate medical education curriculum with focal emphasis on tuberculosis and other infectious diseases. Nigeria, as a TB heavy-burdened state, can not afford to be negligent in her medical education of TB and the training of medical doctors in its management. The results of this study portend a great danger for the control of TB in sub-Saharan Africa. We recommend that similar studies should be carried out in other countries with heavy burdens of TB.