[Contribution of the Xpert MTB / Rif test in the diagnosis of tuberculosis of any form in Saint-Louis]. / Apport du test Xpert MTB/Rif dans le diagnostic de la tuberculose toute forme a Saint-Louis.

INTRODUCTION: The Xpert MTB / RIF assay has a dual advantage on the one hand, the rapid diagnosis of even difficult cases by the standard technique of direct microscopic examination and on the other hand by the detection of resistance to rifampicin. Our objective was to determine the contribution of the Xpert test in the diagnosis of tuberculosis of all forms. MATERIALS AND METHOD: retrospective, descriptive and analytical study carried out in the Pneumophtisiology department of the CHRU of Saint-Louis. All suspected tuberculosis cases who had received an Xpert test from 2018 to 2020 were included. The parameters studied were socio-demographic, clinical and biological data. RESULTS: 524 patient records included in the study with a sex ratio of 1.3. The mean age of the patients was 37 +/-15 years. There were 285 positive GeneXpert samples, of which 224 were of pulmonary origin and 61 of extra-pulmonary origin. The number of rifampicin resistant samples was five, all of respiratory origin. CONCLUSION: the Xpert test is a new molecular technique recommended by the WHO in the diagnosis of pulmonary tuberculosis.

INTRODUCTION: le test Xpert MTB/RIF présente un double avantage d'une part le diagnostic rapide des cas mêmes difficiles par la technique standard de l'examen direct à la microscopie et d'autre part par la détection de la résistance à la rifampicine. Notre objectif était de déterminer l'apport du test Xpert dans le diagnostic de la tuberculose toutes formes confondues. MATÉRIELS ET MÉTHODE: étude transversale, descriptive à collecte rétrospective menée dans le service de Pneumophtisiologie de CHRU de Saint-Louis. Tous les cas suspects de tuberculose qui avaient bénéficié d'un test Xpert de 2018 à 2020avec un dossier médical accessible et exploitable ont été inclus. Les paramètres étudiés étaient les données sociodémographiques, cliniques et biologiques. RÉSULTATS: Nous avions colligés 524dossiers de malades avec un sex-ratio de 1,3. L'âge moyen des patients était de 37 ans+/-15 ans. Il y'avait 285 prélèvements positifs au GeneXpert dont 224 d'origine pulmonaire et 61d'origine extra pulmonaire. Le nombre d'échantillons résistants à la rifampicine était de cinq, tous d'origine respiratoire. CONCLUSION: le test Xpert est une nouvelle technique moléculaire recommandée par l'OMS dans le diagnostic de la tuberculose pulmonaire. Toutefois il doit être évaluer dans le diagnostic de la tuberculose extra pulmonaire.

Sequelae of thoracic tuberculosis: manifestations and patients'quality of life.

For many patients, a history of tuberculosis is synonymous with disabling sequelae, impaired quality of life, and high morbidity and mortality. This retrospective study reviewed the files of patients hospitalized for sequelae of thoracic tuberculosis during 2017, to assess its various manifestations and their impact on quality of life. Of the 176 patients included, 75 % were aged from 35 to 65 years. They were predominantly male, with a sex ratio of 3.76. The socioeconomic level was mostly low (70 %). Only one episode of tuberculosis sufficed to cause sequelae in 89.8 % of cases. Smoking was often noted (52.3 %). Functional signs were dominated by coughs (90.3 %) and dyspnea (72.7 %). Pulmonary sequelae with fibrous scarring were observed in 52.2 % of the patients. Bacterial and/or viral superinfection was the leading cause of hospitalization (50 %). The death rate during hospitalization was 19 %. An improvement followed by discharge was observed for 81 %, 14.2 % of them with chronic respiratory insufficiency. In all, 13.28 % of the discharged patients died within the 6 months that followed. The sequelae of thoracic tuberculosis should be considered as long-term chronic conditions and deserve the same treatment.

[Epidemiology of primary lung cancer among non-smokers in Senegal]. / Épidémiologie des cancers bronchopulmonaires primitifs des non-fumeurs au Sénégal.

INTRODUCTION: According to global data for 2002, one quarter of new cases of primary bronchopulmonary cancer were non-smokers. We undertook this study with the aim of describing the epidemiological characteristics of non-smokers with primary bronchopulmonary cancer in the Dakar region of Senegal. METHODS: A multicenter descriptive study that included all non-smokers who presented with primary bronchopulmonary cancer between January 1st 2014 and December 31st 2015. The data were captured on an Excel file and then transferred to Epi InfoTM 7 software for analysis. RESULTS: The rate of diagnosis for primary bronchopulmonary cancers was 72.1 %. The prevalence of non-smokers was 33.3 %. The sex ratio was 1.27. The average age was 54.6 years. More than a third of the sample were housewives. Carpenters and craftsmen exposed to metals predominated. Exposure to cooking oils was reported in one case. Three patients presented sequelae of pulmonary tuberculosis. Adenocarcinoma was the most common histological type and predominated in young subjects. CONCLUSION: The proportion of primary bronchopulmonary cancers diagnosed among non-smokers is increasing in Dakar. An analytical study of suspected risk factors would be helpful for prevention.

[DRESS syndrome secondary to pyrazinamide: An uncommon complication of tuberculosis treatment]. / DRESS syndrome au pyrazinamide : complication rare et grave du traitement antituberculeux.

INTRODUCTION: The Drug Reaction with Eosinophilia and Systemic Symptom (DRESS) is a severe drug-induced reaction. CASE REPORT: We report the case of a 35-year-old man treated by RHEZ for a first episode of a smear positive pulmonary tuberculosis and who developed a DRESS syndrome due to pyrazinamide after twenty days of treatment, associated with a viral reactivation to Human Herpes Virus 6 (HHV6). He had a skin eruption, liver involvement and hypereosinophilia. He fully recovered after drug withdrawal, associated with local and general corticosteroids. He died two weeks after discharge. CONCLUSIONS: Discovery of DRESS syndrome during tuberculosis treatment is an uncommon complication and requires a searching for the responsible drug. That should be difficult because tuberculosis drugs are often given as fixed-dose combination. Physicians have to bear in mind the potential role of pyrazinamide.

[Clinical and radiological characteristics of pulmonary tuberculosis in tobacco smokers]. / Particularités cliniques et radiologiques de la tuberculose pulmonaire chez le tabagique.

INTRODUCTION: Tobacco smoke alters lung defense mechanisms against infections and so increases the risk of mycobacterium tuberculosis infection. OBJECTIVE: To determine the particular clinical features of tuberculosis in smokers and identify risk factors. METHODS AND PATIENTS: We conducted a prospective, cross-sectional study over a period of nine months in Dakar, Senegal. The Chi-square test and multiple logistic regression were used to identify differences between smokers and non-smokers and to identify factors associated with clinical outcomes. RESULTS: We included 165 patients with active pulmonary tuberculosis (59 smokers versus 106 never-smokers). The average age of smokers was 43.8±12.7 versus 32.1±13.1 years (P<0.0001). Smokers were overwhelmingly male (98.3% versus 1.8%, P<0.0001). The average delay to consultation was longer among smokers (90 days [30-120] versus 60 days [30-90] ; P<0.0001). In multivariate analysis, alcohol abuse, increasing age, male sex, and an unknown retroviral status were independent risk factors for pulmonary tuberculosis. Haemoptysis was observed more frequently in smokers (49.1% versus 31.1%, P=0.017). With regards to chest X-ray features, smokers presented with more advanced, bilateral and cavitating lung lesions. CONCLUSION: Diagnostic delay and haemoptysis are important characteristics of the pulmonary tuberculosis in tobacco smokers.

[Therapeutic itinerary and radiological features of positive microscopy tuberculosis patients at Centre Hospitalier National Universitaire de Fann (CHNUF), Dakar]. / Itinéraire thérapeutique et caractéristiques radiologiques des patients tuberculeux bacillifères dépistés au centre hospitalier national universitaire de Fann (CHNUF), Dakar.

INTRODUCTION: The long diagnostic delay is responsible for the extension of radiological lesions and spread of TB in the community. These radiological lesions can leave significant scars responsible for respiratory disability. OBJECTIVE: The aim of the study is to characterize radiologic features according to tuberculosis diagnostic delay. METHODS: We conducted a prospective cross-sectional study, about 66 patients with positive sputum. RESULTS: The average diagnostic delay was 16 (±15) weeks; whether 22 (±14.1) weeks in the female gender versus 14.6 (±14.3) weeks in the male gender (P=0.10). The first care use was respectively health centers (62.1%), drugstores (51.9%), and traditional medicine (28.7%). Only 27.2% of patients used the marabouts care. Bilateral radiographic abnormalities in bivariate analysis were associated with consultation at the health center (66.7% versus 33.3%; P<0.031), as is the extension of the lesions (70.2% versus 29.8% RP=1.66 [1.05 to 2.91]; P<0.03). Lake of knowledge of the symptoms of TB was associated with the use of marabouts care (12.5% versus 87.5; PR=0.35 [0.11 to 1.08], P<0.04). CONCLUSION: These results should prompt consideration in an emergency, appropriate control interventions, advocacy, patient information and medical personnel on the reality of tuberculosis to prevent its spread often causing respiratory disability with radological effects.

Hepatic cytolysis and bicytopenia after 15 days of four-drug tuberculosis treatment in Senegal.

We report the case of a 31-year-old immunocompetent woman residing in Senegal, with localized microscopy-proved pulmonary tuberculosis, complicated by macrophage activation syndrome and associated with viral hepatitis B, identified due to hepatic cytolysis and a bicytopenia.

[Contribution of fiberoptic bronchoscopy in the diagnosis of pulmonary dragging]. / Apport de la fibroscopie bronchique dans le diagnostic des pneumopathies traînantes.

INTRODUCTION: Bronchoscopy is recommended into the exploration of chronic lung diseases. This one is expensive and invasive. We conducted this study in order to assess the benefit of the bronchoscopy in the etiologic diagnosis of chronic lung diseases. PATIENTS AND METHODS: This study was retrospective, descriptive and analytical, using medical records of outpatients and in patients who has done the bronchoscopy in Pneumology Clinic, Fann hospital, Dakar from January 2010 to December 2014. RESULTS: We have reported 159 cases. The sex ratio was 2.2. Middle age was 44 years. Fever was found in 32.7%. Alveolar syndrome was found in 64.8%. The white blood cells (WBC) were normal in 80.7%. Bronchoscopy was contributive in 74.1%. Specimen analysis isolated banals germs in 69.2%, mainly bacteria in 51.6%. Parasitology of the fluid of broncho-alveolar lavage was positive in 28.6%. CONCLUSION: Bronchoscopy stills a use full exploration while diagnosing chronic lung diseases. It should be systematic in chronic lung diseases with or not fever, this, when sputum microscopy a sputum PCR are negative.

[Prevalence of tobacco smoking in primary and secondary schools in the Department of Dakar, Senegal]. / Prévalence du tabagisme dans l'enseignement moyen et secondaire dans le Département de Dakar, Sénégal.

INTRODUCTION: Tobacco smoke is a global health problem, and the largest avoidable cause of death in the world. The objective of our study was to determine the prevalence of tobacco smoking in schools in Dakar area (Senegal). MATERIEL AND METHODS: This descriptive and analytical cross-sectional study was performed from September 2011 to June 2012 in 27 schools of the Dakar area. RESULTS: We questioned 1654 students over a 9-month school period. The mean age was 15±2.5years (range 11-22). The sample included 848 boys (51.3 %), therefore a sex ratio of 1.05. There were 68 smokers (4.1 %) and 60 ex-smokers (3.6 %). The mean age of the smokers was 16.9±2.2years (range 11-22) with a male preponderance of 70.6 % (n=48). Smoking in family members was the initiating factor most frequently reported by smokers (25 %). The average age of ex-smokers was 16.4±2years. Fear of parents' reactions was the most frequently invoked reason for stopping smoking (41.7 %). CONCLUSION: This study confirms the reality of smoking among school children in Senegal and highlights the urgency of the installation of a prevention policy near the young people.

Comprehensive phylogenetic reconstructions of Rift Valley fever virus: the 2010 northern Mauritania outbreak in the Camelus dromedarius species.

Rift valley fever (RVF) is a mosquito-borne disease of domestic and wild ruminants caused by RVF virus (RVFV), a phlebovirus (Bunyaviridae). RVF is widespread in Sub-Saharan Africa. In September of 2010, an RVF outbreak occurred in northern Mauritania involving mass abortions in small ruminants and camels (Camelus dromedarius) and at least 63 human clinical cases, including 13 deaths. In camels, serological prevalence was 27.5-38.5% (95% confidence interval, n=279). For the first time, clinical signs other than abortions were reported in this species, including hemorrhagic septicemia and severe respiratory distress in animals. We assessed the presence of RVFV in camel sera sampled during this outbreak and generated whole-genome sequences of RVFV to determine the possible origin of this RVFV strain. Phylogenetic analyses suggested a shared ancestor between the Mauritania 2010 strain and strains from Zimbabwe (2269, 763, and 2373), Kenya (155_57 and 56IB8), South Africa (Kakamas, SA75 and SA51VanWyck), Uganda (Entebbe), and other strains linked to the 1987 outbreak of RVF in Mauritania (OS1, OS3, OS8, and OS9).

[Smoking among health workers at four large hospitals in Dakar (Senegal)]. / Le tabagisme chez le personnel médical et paramédical dans quatre grands hôpitaux de Dakar.

INTRODUCTION: The addiction to tobacco remains a significant problem in the context of medical practice in African in general and in Senegal in particular. It is an important cause of morbidity and mortality. The main purposes of this study were to establish the smoking habits of hospital staff as a step towards elaborating a strategy for an anti-smoking campaign within the hospital environment. PATIENTS AND METHOD: The study was a cross-sectional, prospective, descriptive going study conducted between 1st March 2007 and May 15th, 2008. We recovered 662 out of 750 questionnaires collected representing a 75% participation rate. RESULTS: Eighty-five respondents reported that they were smokers (12.8%). The sex-ratio was 7.5 times more common in men. The paramedical staff were more likely to smoke than doctors (14% versus 12.2%). The average age of the smokers was of 37.4 years. Women had begun to smoke at an earlier age (17.4 years against 20.5 years). According to the Fagerström test, 87% were averagely or strongly dependent on nicotine. It was mainly the pleasure (41.2%) and the influence of their circle of acquaintances (36.5%) that prompted the staff to smoke. Smoking cessation was most commonly achieved through the use of willpower alone (44.4%). CONCLUSION: The mortality and morbidity arising from the addiction to smoking is entirely avoidable in contrast to other pandemics. Consequently, engagement in the fight against smoking must constitute a major priority for health workers who must set an example for their patients.

[Miliary tuberculosis: a report of 49 cases]. / Miliaire tuberculeuse: à propos de 49 cas.

INTRODUCTION: Miliary tuberculosis is a severe, acute form of tuberculosis due to lymphohaematogenous dissemination of tubercle bacilli from a focal lesion. PATIENTS AND METHODS: A prospective study of was undertaken at the Pneumology Clinic of the National University Hospital Centre (CHUN) of Fann, over a period of 30 months (January 2007-June 2009), in order to assess the epidemiological, clinical, paraclinical and evolutionary aspects of miliary tuberculosis. RESULTS: Miliary tuberculosis accounted for 3.8% (n=49) of all diagnosed cases of tuberculosis. The sex-ratio was 1.7. The average age of patients was 37.5 years with a range of 15 to 70 years. The typical radiological appearances were present in 88% of cases whereas only 10% were positive on direct smear. HIV serology was positive in 29%. In the hospital environment, the mortality was 12.2%. CONCLUSION: Miliary tuberculosis is a severe form of the disease. The prognosis depends on early diagnosis and treatment.

[Epidemiological, clinical, therapeutic and evolutionary aspects of pulmonary aspergilloma in Dakar]. / Aspects épidémiologiques, cliniques, thérapeutiques et évolutifs de l'aspergillome pulmonaire à Dakar.

INTRODUCTION: The presentation of pulmonary aspergilloma is dominated by haemoptysis, the results of medical treatment are disappointing and there is significant morbidity and mortality following surgery; the only really curative treatment. These facts emphasise the gravity of this condition. We undertook a study to estimate the current profile of the disease and its management in Senegal. PATIENTS AND METHODS: A retrospective study took place between January 2004 and September 2008 including all the cases of pulmonary aspergilloma diagnosed in private practice and\or the thoracic and cardiovascular surgery service of the Fann Hospital, Dakar. RESULTS: Thirty-five patient records were collected. The sex ratio was four males to one female. The average age of the patients was 43.7 years. All the patients had a history of pulmonary tuberculosis. Serology was positive for Aspergillus fumigatus at 22 patients out of 29 (75.86%). Histological examination of surgical biopsies confirmed the diagnosis in 88.46%. The treatment was essentially surgical with no recorded mortality. Nine cases of haemorrhage and eight of suppuration were reported. CONCLUSION: Surgery remains the reference treatment for pulmonary aspergilloma. In view of the morbidity of this condition we emphasize the importance of early screening and correct treatment of tuberculosis, particularly in endemic countries, to achieve clinical cure and prevent serious after effects.

[Tuberculosis in elderly persons]. / Tuberculose du sujet âgé

OBJECTIVES: The purpose of this study was to compare the epidemiology, clinical features and clinical course of primary presentations with pulmonary tuberculosis occurring in older and younger patients. PATIENTS AND METHODS: We undertook a prospective, comparative study in the Pneumology clinic of the National University Hospital of Fann in Dakar, from April 1, 2005 to March 31, 2006, collecting data on all patients presenting with a first episode of bacterially confirmed pulmonary tuberculosis. RESULTS: We studied 187 first presentations with confirmed pulmonary tuberculosis including 12.8% (n=24) elderly (>55 years) subjects (20 men and four women) and 87.2% (n=163) younger subjects (105 men and 58 women). In the older subjects, patients were more commonly men (sex-ratio: 5), without formal education, and working in the primary or informal sector. Comorbidities were more frequent in the older group, including smoking (P=0.002), alcohol consumption (P=0.01), diabetes (37.5%) (P<0.005) and obesity with BMI superior than 20 in 25%. Pulmonary shadowing was common (41.7% of the cases), P=0.008 and generally bilateral P=0.0001 with cavitation, but this observation was not statistically significant. COMPLICATIONS: Complications were more frequent in the older patient (20.8%), as was mortality (29.3%, P=0.000) and rate of clinical improvement in response to treatment was less satisfactory (50%) there.

[Etiology of spontaneous pneumothorax in Senegal: prospective study in Dakar University Hospital]. / Etiologies du pneumothorax spontané au Sénégal: étude prospective au CHU de Fann-Dakar.

Pneumothorax is defined as the presence of air in the pleural space. There is a paucity of data on pneumothorax in Senegal. The purpose of this prospective study conducted over a 18-month period was to determine the etiological and clinical characteristics of spontaneous pneumothorax in Senegal. This study was conducted in the respiratory disease unit of Dakar University Hospital between June 2005 and November 2006. All patients over the age of 15 years admitted with a diagnosis of spontaneous pneumothorax were included. Sociodemographic, clinical, radiological and biological data were recorded for all patients. Of the 1,053 patients admitted to the unit during the study period, 73 (6.93%) presented spontaneous pneumothorax that was classified as primary in 8 cases and secondary in 65. Median patient age was 32 years (range, 16 to 86). The male-to-female ratio was 3.6/1. The most common cause of secondary spontaneous pneumothorax was pulmonary tuberculosis followed by emphysema. The findings of this study indicate that secondary spontaneous pneumothorax is predominant in Senegal. Pulmonary tuberculosis that is endemic in the country is the main cause of secondary spontaneous pneumothorax and accounts for almost 3/4 of cases.

[Smoking among students at the School of Health and Social Development and the Health Service Institute in Senegal]. / Le tabagisme chez les élèves de l'Ecole de Développement Sanitaire et Social et de l'Institut Santé Service.

We have undertaken a transverse study of smoking among students at the National School of Health and Social Development (ENDSS) and the Health Service Institute (ISS) in Senegal. 683 out of 1142 students were questioned. 609 (89%) replied, of whom 313 (52%) were at the ENDSS and 293 (48%) at the ISS. Senior technical students were most strongly represented at 37.8%, followed by student nurses (27.4%) and midwifery students (23.3%). There were more women (n=378) than men with a sex ratio of 0.61. The average age of the population was 27.5 +/- 6.8 years (range 15 to 58). The average age was 26.2 +/- 5.6 years in the women and 29.6 +/- 8 in the men. The group aged 25-34 was significantly the most affected in both men and women (p=0.0000). The population comprised 502 non-smokers (82.4%), 62 ex-smokers (10.2%) and 45 smokers (7.4%).We found variable alcohol consumption in 119 subjects (19.2%) and 5 students admitted using cannabis. The 62 ex-smokers made up 10.2% of the population. The average age was 31.4 years. 25 ex-smokers (40.3%) drank alcohol, with a sex ratio of 1.95. The reasons for stopping smoking were illness and guilt in 27.4% of cases respectively, economic in 24.2%, medical statements on the effects of smoking on health in 17.7% and personal wishes in only 11.3%. The smokers, numbering 45 (7.4%), had an average age of 27.6 +/- 6.6 years with a sex ratio of 2 (p=0.00000). The age of starting smoking was 20.7 +/- 4.2 years for the women and 19.9 +/- 2.9 years for the men. The latter had smoked for an average of 9.2 years. Cigarettes were used by the great majority of smokers. It was associated with alcohol consumption in 35.6% and cannabis in 11.1% of cases. In the men the motives for starting smoking were stress (60%), pleasure (55.2%) and social influence (53.3%). By contrast, among the women, the two main reasons were stress and fashion in 60% (p=0.04). Our students smoked mostly in public places and in their homes. 34 smokers (75.6%) wished to stop (p=0.02) but only 27 of them expressed the need for medical or psychological support to do this. Dependence, quantified by the Fagerström Score, was medium (score 5-6) in 60% (n=27) and strong (score 7-10) in 31.1% (n=14).The estimated monthly cost of smoking increased with the degree of dependence. It was, on average, 12,143 F CFA (18.5euro) in cases of high dependence, representing 37% of the minimum wage in Senegal which is 33000F CFA (50euro). The students understood well the diseases caused by smoking (whether they were smokers, ex-smokers or non-smokers). These comprise mainly pulmonary diseases (96.2%) and cardio-vascular diseases (78.3%) All the recommended methods of the fight against smoking presented in the media, the publicity, national anti-smoking campaigns, personal contact and consultation, received more than 60% of favourable opinions among the total population studied.

A comparative kinetic study of doramectin and moxidectin in zebu Gobra cattle (Bos indicus).

The plasma kinetics of doramectin and moxidectin were evaluated in zebu Gobra under field conditions after subcutaneous administration of 0.2 mg kg(-1) of commercially available formulations for cattle. The results indicate that the absorption of moxidectin from the site of injection was significantly faster (absorption half-life [t1/2ab] = 0.7 day) than that of doramectin (t1/2ab = 3.1 days). Moxidectin peak plasma concentration (Cmax) was reached significantly earlier (tmax = 0.4 day) compared with that of doramectin (tmax = 5.3 days). No differences in Cmax values were observed; the area under the concentration-time curve was higher for doramectin (475 ng day ml(-1)) compared with moxidectin (198 ng day ml(-1)), while the mean residence time was longer for moxidectin (13.4 days) compared with doramectin (9.4 days). These results obtained give interesting information on doramectin and moxidectin pharmacokinetics in zebu Gobra, which show a similar pharmacokinetic profile as in other cattle.

[Clinical, biological and radiological spectrum of newly diagnosed pulmonary tuberculosis]. / Profil clinique, biologique et radiologique des nouveaux cas de tuberculose pulmonaire au Centre Hospitalier Universitaire de Fann-Dakar.

The aim of the present study was to describe the clinical, biological and the chest-X ray presentations of newly diagnosed pulmonary tuberculosis. A retrospective study of 200 patients was performed from January to October 2004 in the respiratory diseases unit of Dakar's University Teaching Hospital. Among the 200 cases, 140 (70%) were male, giving a sex ratio of 2.3. The mean age of our patients was 35.5 years (range: 14-81 years). The group age of 20 to 39 years was the most affected (55,5% of patients). The median diagnostic delay was 4 months (range: 7 days to 2 years). Haemoptysis revealed the disease in 27% of cases. The chest X-ray showed bilateral lesions in 65% of cases. When they were unilateral, the right side was the most concerned. Of the 200 patients, the lesions interested all parts of at least one lung in 106 (53%). Among our patients, 153 (76.5%) had cavitations and 145 (72.5%) had infiltrates. A pleural effusion was associated to the lung lesions in 10% of the patients. Biologically, we reported 80% cases (n=160) of hypochromic microcytic anaemia. Of the 27 HIV tests done, 18 (66.7%) were positive all for HIV1. Delay in the diagnosis of pulmonary tuberculosis was very long and our data illustrate the need for improved education of the community and event of healthcare workers about the benefit of early diagnosis of tuberculosis.