Use of light-emitting diode fluorescence microscopy to detect acid-fast bacilli in sputum as proficient alternative tool in the diagnosis of pulmonary tuberculosis in countries with limited resource settings.

Background: Despite recent advances in the development of more sensitive technologies for the diagnosis of tuberculosis (TB), in resource-limited settings, the diagnosis continues to rely on sputum smear microscopy. This is because smear microscopy is simple, cost-efficient and the most accessible tool for the diagnosis of TB. Our study evaluated the performance of light-emitting diode fluorescence microscopy (LED-FM) using auramine/rhodamine (auramine) and the fluorescein di-acetate (FDA) vital stain in the diagnostic of pulmonary TB in Bamako, Mali. Methods: Sputum smear microscopy was conducted using the FDA and auramine/rhodamine staining procedures on fresh samples using LED-FM to evaluate the Mycobacterium TB (MTB) metabolic activity and to predict contagiousness. Mycobacterial culture assay was utilized as a gold standard method. Results: Out of 1401 TB suspected patients, 1354 (96.65%) were retrieved from database, which were MTB complex culture positive, and 47 (3.40%) were culture negative (no mycobacterial growth observed). Out of the 1354 included patients, 1343 (95.86%), were acid-fast bacillus (AFB) positive after direct FDA staining, 1352 (96.50%) AFB positive after direct Auramine, and 1354 (96.65%) AFB positive with indirect auramine after digestion and centrifugation. Overall, the FDA staining method has a sensitivity of 98.82%, while the sensitivity of Auramine with direct observation was 99.48%, and 99.56% with the indirect examination. Conclusion: This study showed that, using fresh sputum both auramine/rhodamine and FDA are highly sensitive methods in diagnosing pulmonary TB and could be easily used in countries with limited resource settings.

Mycobacterium africanum (Lineage 6) shows slower sputum smear conversion on tuberculosis treatment than Mycobacterium tuberculosis (Lineage 4) in Bamako, Mali.

OBJECTIVE: Ancestral M. tuberculosis complex lineages such as M. africanum are underrepresented among retreatment patients and those with drug resistance. To test the hypothesis that they respond faster to TB treatment, we determined the rate of smear conversion of new pulmonary tuberculosis patients in Bamako, Mali by the main MTBc lineages. METHODS: Between 2015 and 2017, we conducted a prospective cohort study of new smear positive pulmonary tuberculosis patients in Bamako. Confirmed MTBc isolates underwent genotyping by spoligotyping for lineage classification. Patients were followed at 1 month (M), 2M and 5M to measure smear conversion in auramine (AR) and Fluorescein DiAcetate (FDA) vital stain microscopy. RESULT: All the first six human MTBc lineages were represented in the population, plus M. bovis in 0.8% of the patients. The most widely represented lineage was the modern Euro-American lineage (L) 4, 57%, predominantly the T family, followed by L6 (M. africanum type 2) in 22.9%. Ancestral lineages 1, 5, 6 and M. bovis combined amounted to 28.8%. Excluding 25 patients with rifampicin resistance, smear conversion, both by AR and FDA, occurred later in L6 compared to L4 (HR 0.80 (95% CI 0.66-0.97) for AR, and HR 0.81 (95%CI 0.68-0.97) for FDA). In addition we found that HIV negative status, higher BMI at day 0, and patients with smear grade at baseline ≤ 1+ were associated with earlier smear conversion. CONCLUSION: The six major human lineages of the MTBc all circulate in Bamako. Counter to our hypothesis, we found that patients diseased with modern M. tuberculosis complex L4 respond faster to TB treatment than those with M. africanum L6.

[The Hospital Wastewater Antibiotic Residues In Bamako (Mali)]. / Les Residus D'Antibiotiques Dans Les Effluents Hospitaliers De Bamako (Mali).

The aim of this study was to determine the wastewaters antibiotic residues concentration in two hospitals (CHU Point G and CHU Luxembourg) in Bamako. METHODS: The samples of wastewater were collected three times consecutively on three days every week at 9 a.m., 3 p.m. and 9 p.m. in 2016. The samples were stored at 4°C and transferred to the veterinary central laboratory (LCV). The antibiotic residues were detected by High Performance Liquid Chromatography and the antibiotic concentrations were determined by a spectrophotometer UV-Visible Hewlett Packard. RESULTS: The detected and measured antibiotic residues were amoxicillin ((0.066 ± 0.08 µg/l), erythromycin (0.04 ± 0.0 µg/l), co-trimoxazole (sulfamethoxazole 0.06 ± 0.21 µg/l + trimethoprime 0.08 ± 0.006 µg/l) and metronidazole (0.02 ± 0.0 µg/l in the hospital wastewater and in the sewer systems. Amoxicillin and sulfamethoxazole were detected before and after the Point G wastewater treatment. No antibiotic residue was detected in the "Chikoroni" sewer system which discharged the Point G wastewater. Amoxicillin and sulfamethoxazole were also detected in the wastewater of the hospital "le Luxembourg" which doesn't have a wastewater treatment plant and in the "Djafranako" sewer system which discharged the wastewater of this hospital. Erythromycin and metronidazole were detected only in the Point G wastewater. Chloramphenicol, ciprofloxacin and tetracyclin were not detected in the two hospital wastewater. The antibiotic residues concentrations at the different moments show the same high level in the different sites. CONCLUSION: Hospitals play a role in the antibiotic dissemination into the environment. In Bamako, the wastewater quality is not alarming, but every hospital must get a sewer system.

L'objectif de ce travail était de déterminer la concentration des résidus d'antibiotiques dans les effluents de deux hôpitaux de Bamako. MÉTHODES: La collecte des échantillons des effluents hospitaliers a été réalisée trois fois par jour à des heures précises : 9 heures, 15 heures et 21 heures conformément au moment des rejets de la station d'épuration, trois jours consécutifs par semaine et pendant un mois. L'analyse des échantillons a été faite par chromatographie phase liquide (HPLC), Agilent 1100 sur colonne C18. La concentration des antibiotiques a été mesurée à l'aide d'un spectrophotomètre UV-Visible Hewlett Packard. RÉSULTATS: Quatre antibiotiques ont été détectés et quantifiés dont trois régulièrement dans les effluents hospitaliers. Il s'agit de l'amoxicilline (0,066 ± 0,08 µg/l), l'érythromycine (0,04 ± 0,0 µg/l), sulfaméthoxazole + triméthoprime (0,06 ± 0,21 / 0,08 ± 0,006 µg/l) et du métronidazole (0,02 ± 0,0 µg/l). L'amoxicilline et le sulfaméthoxazole ont été détectés et quantifiés sur les deux points, l'érythromycine et le métronidazole seulement au CHU du Point « G ¼. Le sulfaméthoxazole a été dosé aux différentes heures dans les effluents des deux hôpitaux, il n'est pas détecté dans les eaux du canal de « Chikoroni ¼. Le chloramphénicol, la ciprofloxacine et la tétracycline n'ont été détectés à aucun point de prélèvement. Les concentrations d'antibiotiques observées aux différentes heures de prélèvements montrent des pics en général semblables au niveau des différents sites. CONCLUSION: La qualité de nos effluents n'est pas aussi alarmante. Des mesures doivent être prises en vue de l'évaluation du risque sanitaire et du développement des méthodes nécessaires pour limiter les rejets de résidus médicamenteux dans l'environnement.

Very high prevalence of extended-spectrum beta-lactamase-producing Enterobacteriaceae in bacteriemic patients hospitalized in teaching hospitals in Bamako, Mali.

The worldwide dissemination of extended-spectrum beta-lactamase producing Enterobacteriaceae, (ESBL-E) and their subset producing carbapenemases (CPE), is alarming. Limited data on the prevalence of such strains in infections from patients from Sub-Saharan Africa are currently available. We determined, here, the prevalence of ESBL-E/CPE in bacteriemic patients in two teaching hospitals from Bamako (Mali), which are at the top of the health care pyramid in the country. During one year, all Enterobacteriaceae isolated from bloodstream infections (E-BSI), were collected from patients hospitalized at the Point G University Teaching Hospital and the pediatric units of Gabriel Touré University Teaching Hospital. Antibiotic susceptibility testing, enzyme characterization and strain relatedness were determined. A total of 77 patients had an E-BSI and as many as 48 (62.3%) were infected with an ESBL-E. ESBL-E BSI were associated with a previous hospitalization (OR 3.97 95% IC [1.32; 13.21]) and were more frequent in hospital-acquired episodes (OR 3.66 95% IC [1.07; 13.38]). Among the 82 isolated Enterobacteriaceae, 58.5% were ESBL-E (20/31 Escherichia coli, 20/26 Klebsiella pneumoniae and 8/15 Enterobacter cloacae). The remaining (5 Salmonella Enteritidis, 3 Morganella morganii 1 Proteus mirabilis and 1 Leclercia adecarboxylata) were ESBL negative. CTX-M-1 group enzymes were highly prevalent (89.6%) among ESBLs; the remaining ones being SHV. One E. coli produced an OXA-181 carbapenemase, which is the first CPE described in Mali. The analysis of ESBL-E relatedness suggested a high rate of cross transmission between patients. In conclusion, even if CPE are still rare for the moment, the high rate of ESBL-BSI and frequent cross transmission probably impose a high medical and economic burden to Malian hospitals.

Prevalence of ESBL-producing Enterobacteriaceae isolated from blood cultures in Mali.

INTRODUCTION: The increasing frequency of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae is becoming a serious public health concern. This study sought to determine ESBL frequency in Enterobacteriaceae isolated from patients' blood cultures in two university teaching hospitals of Bamako, Mali. METHODOLOGY: During a three-month period, the presence of Enterobacteriaceae from blood cultures of patients admitted to the university teaching hospitals of Bamako was evaluated. The microbial identifications were initially performed with an API 20E gallery and VITEK2 locally in Mali, and then confirmation in France was performed with a mass spectrometry MALDI-TOF in the bacteriology laboratory of the university teaching hospital of Bichat. Antibiotic susceptibility profiles were determined by the diffusion method as recommended by the European Committee on Antimicrobial Susceptibility Testing (EUCAST). RESULTS: The isolated species were K. pneumoniae (14/40; 35.0%), E. coli (11/40; 27.5%), and E. cloacae (9/40; 22.5%). Of the strains isolated, 21/34 (61.8%) had an ESBL phenotype, including 10/14 (71.4%) K. pneumoniae, 8/11 (72.7%) E. coli, and 3/9 (33.3%) E. cloacae. Resistances associated with ESBL strains of K. pneumoniae, E. coli, and E. cloacae were as follows: gentamicin (10/10, 100%; 6/8, 75%; 2/3, 67%, respectively), amikacin (2/10, 20%; 0/8, 0%; 0/3, 0%, respectively), ofloxacin (8/10, 80%; 7/8, 87%; 3/3, 100%, respectively), and cotrimoxazole (10/10, 100%; 6/8, 75%; 3/3, 100%, respectively). CONCLUSION: Almost two-thirds (61.8%) of Enterobacteriaceae isolated from our blood cultures were ESBL producers. Only susceptibilities to carbapenems and to amikacin were fully conserved within the strains.

[Seroprevalence of the human cytomegalovirus among blood donors and AIDS patients in Bamako]. / La séroprévalence de l'infection par le cytomégalovirus humain chez les donneurs de sang et les malades atteints du sida à Bamako.

Our aim was to study the prevalence of the human cytomegalovirus (HCMV) among blood donors and AIDS patients and to examine a clinical correlation between AIDS and HCMV seroprevalence in Bamako (Mali, West Africa). We have used Elisa kits for detecting HIV and HCMV specific antibodies. The HCMV seroprevalence was 89% among AIDS patients, 71% among HIV-infected blood donors and 58% among HIV-uninfected blood donors. The HCMV seroprevalence rate was higher among AIDS patients than among HIV-uninfected blood donors (p=0.0000007) and than among HIV-infected blood donors (p=0.00146). There was no significant difference between the HCMV seroprevalence among HIV-infected blood donors and among HIV-uninfected blood donors (p=0.0547). There was no relationship between HCMV seroprevalence and sex or age among AIDS patients and blood donors. There was a significant difference on pneumonia among HCMV-infected AIDS patients and among HCMV-uninfected AIDS patients (40% versus 0%; p=0.005). Buccal and phaiyngal candidosis, dermatosis, Kaposi's sarcoma and nervous system diseases had the same frequency among HCMV-infected and HCMV-uninfected AIDS patients.