Pulmonary tuberculosis: Evaluation of current diagnostic strategy.

OBJECTIVE: To identify tools that will result in faster diagnosis, making the current pulmonary tuberculosis strategy more efficient. PATIENTS AND METHODS: A 4-year (2015-2018) retrospective study. The gold standard for diagnosis was a positive culture from a respiratory specimen. All sputum, fibroscopy and post-fibroscopy specimens (for smear negative patients) were collected. Each specimen was analyzed through smear examination and culture. All nucleic acid amplification testing results were included. Analyses looked at the incremental yield of positive cases of each successive specimen collection, and time to diagnosis. RESULTS: A total of 354 patients had at least one positive culture. Sputum allowed a diagnosis in 92% of cases (including a gain in sensitivity of around 7% for the third sputum specimen), with 160 smear-positive patients (45%). Among smear-negative patients, 109 underwent a fibroscopy procedure (culture sensitivity of 75%), and 59 had a post-fibroscopy specimen collected, which together identified the rest of the patients (8%). Molecular testing was used in 237 specimens. Median time to diagnosis was 11 days, which was significantly reduced among smear-negative patients when molecular testing was used (P<0.001). Shortening the delay between sputum specimen collections did not alter procedure sensitivity. CONCLUSIONS: We identified several aspects of the French tuberculosis diagnosis algorithm that could be improved, and posed the basis for a prospective study. Centers in higher incidence areas could benefit from a dedicated, predefined procedure exploring suspicions of tuberculosis. A high suspicion score of tuberculosis could drive the reasoned use of molecular testing in such settings.

[Treatment duration of extra-pulmonary tuberculosis: 6 months or more? TB-INFO database analysis]. / Durée de traitement des tuberculoses extrapulmonaires : six mois ou plus ? Analyse de la base de données TB-INFO.

PURPOSE: The recommended duration of pulmonary tuberculosis therapy is 6 months. For extrapulmonary tuberculosis, treatment duration depends on tuberculosis involvement and HIV status. The objective of this study was to describe the main characteristics of a cohort of extrapulmonary tuberculosis patients, to compare patients with a 6-month treatment to those with more than a 6-month treatment, and to analyze the compliance of medical centres with recommended duration of treatment. METHODS: A retrospective cohort study of 210 patients with extrapulmonary tuberculosis was carried from January 1999 to December 2006 in two hospitals in the north-east of Paris. These patients were treated with quadruple therapy during two months, followed by dual therapy during 4 months (n=77) or more (n=66). The characteristics of each group were compared by uni- and multivariate analysis. The primary endpoint was the rate of relapse or treatment failure at 24-month follow-up after treatment completion. RESULTS: No relapse was observed after 24 months of follow-up after the end of treatment in the two groups. In univariate analysis, patients with lymph node tuberculosis were more often treated for 6 months than at other sites of tuberculosis (respectively 61% versus 40.9%; P=0.02); the decision of treatment duration was related to medical practices (79.2% treated 6 months in one hospital versus 20.7% in the other, P<0.001); patients living in private residence were more often treated during 6 months than patients living in residence (24.2% versus 10.3%, P=0.042). In multivariate analysis, only hospital (P=0.046), sex (P=0.007) and private residence were significantly different in each group. CONCLUSION: A period of 6 months seems to be sufficient to treat extrapulmonary tuberculosis (except for neuromeningeal localization).

[Multidrug-resistant tuberculosis management in three French hospitals]. / Prise en charge de la tuberculose multirésistante dans trois hôpitaux français.

INTRODUCTION: Multidrug-resistant tuberculosis (MDR-TB) management is based on specific WHO guidelines. OBJECTIVES: The authors report MDR-TB management, in three French hospitals. METHOD: The authors retrospectively included patients with positive sample for multidrug-resistant Mycobacterium tuberculosis (isoniazid+rifampicin) from January 1, 2000 to December 31, 2005. The management was compared to the French and international prevalent guidelines. RESULTS: Sixteen patients were initially managed for MDR-TB by eight different medical teams over 6 successive years: 12 (75%) presented with primary MDR-TB. Management advice from the national referee center (NRC) for tuberculosis was reported in seven out of 14 treated cases. The median length of the intensive treatment was 2 months (IQR: 1-3). Eight patients (58%) had an overall treatment length of 18 months. The median number of effective drugs prescribed was 4 (IQR: 4-5). Nine patients (64%) were also managed in a sanatorium. Only eight patients (57%) completed the prescribed treatment. Nine patients were clinically cured and still followed-up, six of whom were bacteriologically cured. CONCLUSION: TB-MDR management was not conform to WHO guidelines in our study. Management in a sanatorium, NRC involvement, ambulatory DOT were highly beneficial.

[Comparison of three Clostridium difficile culture media: interest of enhancing spore germination media?]. / Comparaison de trois milieux pour la culture de Clostridium difficile: intérêt des milieux favorisant la germination des spores?

AIM: Clostridium difficile is the most common agent of postantibiotic and nosocomial bacterial diarrhoea. Since the emergence of the highly virulent and epidemic strain NAP1/027 in Europe, it appears necessary to isolate C. difficile strains to realize an epidemiologic follow-up by molecular typing. The aim of this work was to compare three selective culture conditions for the isolation of C. difficile. METHODS: One hundred and thirty stools collected from patients hospitalized at Jean Verdier were swabbed on the commercial medium CLO (BioMérieux) and on a medium prepared at the laboratory (CCTa: Columbia, cefoxitine 8 mg/l, cycloserine 250 mg/l, horse blood 5 %, sodium taurocholate 0.1 %) with and without preliminary alcoholic shock (EtOH). C. difficile was isolated from 38 stools and colonies were counted on each medium. RESULTS: The fluorescence intensity of C. difficile colonies is comparable on CLO and CCTa-EtOH media, however their aspect is more characteristic on CLO. This medium appears very selective contrary to the CCTa medium on which an associated flora obstructs the fluorescence reading and requires a new isolation of the suspect strains. On average 30 times more colonies of C. difficile are counted on CCTa+/-EtOH than on CLO, suggesting the presence of great proportions of spores in the stools. CONCLUSIONS: The medium CLO is successful for the isolation of C. difficile despite of its selectivity. Nevertheless, it appears interesting to associate a medium enhancing spore germination as the CCTa medium inoculated after alcoholic shock to increase the sensitivity of detection while being freed from conservation and transport conditions.

[Epidemiological study of Clostridium difficile strains isolated in Jean-Verdier-René-Muret hospitals from 2001 to 2007]. / Evolution épidémiologique de souches de Clostridium difficile isolées d'infections dans le CHU Jean-Verdier-René-Muret entre 2001 et 2007.

Clostridium difficile is the most common agent of nosocomial bacterial diarrhoea in adults. In 2006, C. difficile outbreaks were described in France with the highly virulent strain PCR-ribotype 027, which is also resistant to moxifloxacin and erythromycin. The aim of this study is to perform a phenotypic and molecular characterization of C. difficile strains isolated in Jean-Verdier-René-Muret hospitals. Thirty three C. difficile toxigenic strains isolated in symptomatic patients from 2001 to 2007 were studied. Toxins A and B detection was performed with an immunoenzymatic method (ICTAB, Meridian). The agar diffusion method was performed for determination of antibiotic susceptibility for metronidazole, vancomycin, erythromycin and moxifloxacin. The E-test was performed for determination of metronidazole, vancomycin and tigecycline MIC. Binary toxin genes cdtA and cdtB were detected by PCR. PCR-ribotyping was performed according to Bidet et al. From 2001 to 2007, all the isolates studied were susceptible to metronidazole, vancomycin and tigecyclin. We observed a significant decrease of susceptibility to moxifloxacin (100% in 2001 versus 28.5% in 2007) and to erythromycin (60% in 2001 versus 14% in 2007). Toxins A/B were detected in all the isolates. Fifteen per cent of the isolates studied produced the binary toxin not correlated with a specific PCR-ribotype. Ribotype 18 was the most prevalent PCR-ribotype detected since 2006. The isolates displaying this PCR-ribotype were resistant to erythromycin and moxifloxacin and were principally isolated in the same ward, suggesting cross infection. This study showed that: (1) over a six-year period, the susceptibility to metronidazole and vancomycin remained stable; (2) different clones of C. difficile circulated during these six years. Recently an epidemic strain resistant to erythromycin and moxifloxacin of ribotype 18 has emerged in the gastroenterology unit where fluoroquinolones are frequently used demonstrating the role of antibiotic selection pressure. The emergence of these isolates could explain the significant decrease of susceptibility to moxifloxacin and erythromycin observed in 2007. However, today, no isolate with a PCR-ribotype 027 was detected.

[Interest of the disk diffusion method for screening Clostridium difficile isolates with decreased susceptibility to antibiotics]. / Evaluation de l'antibiogramme par diffusion en milieu gélosé pour le dépistage de souches de Clostridium difficile de sensibilité diminuée aux antibiotiques.

AIM: In vitro determination of Clostridium difficile susceptibility to antibiotics is not routinely performed. The aim of this study was to evaluate the performance of antibiotic susceptibility determination with the disk diffusion method for screening C. difficile isolates with decreased susceptibility to antibiotics. METHODS: Thirty-six C. difficile isolates (toxigenic or not) isolated in 2005 and 2006 from three hospitals Assistance publique-Hôpitaux de Paris (Jean-Verdier, René-Muret, Beaujon) were studied by disk diffusion method with 14 antibiotics. Mueller-Hinton agar supplemented with sheep blood (Bio-Rad*) were swabbed with a C. difficile suspension at 1 McFarland. To check the results obtained with the disk diffusion method, Minimal Inhibitory Concentration (MIC) were performed respectively with E-test for glycopeptides and metronidazole and with the agar dilution reference method and E-test for new molecules with a potential activity against anaerobes: imipenem, ertapenem, linezolid and moxifloxacin. RESULTS: The decreased susceptibility (resistant and intermediate) observed was 40% for amoxicillin-clavulanate, 60% for piperacillin-tazobactam, 100% for ceftriaxone, 81% for imipenem, 61% for ertapenem, 2% for chloramphenicol, 34% for erythromycin, 90% for lincomycin, 2% for linezolid, 98% for levofloxacin, 17% for moxifloxacin and 0% for vancomycin, teicoplanin and metronidazole. The results obtained with the disk diffusion method were compared to MICs obtained with E-test and reference method. CONCLUSION: The disk diffusion method seems to be a good method to detect isolates suspected to have a decreased susceptibility and consequently to reduce MIC determinations.

[In vitro activity of moxifloxacin (8-methoxyquinolone) alone or in combination with cefotaxime against group B streptococci]. / Activité in vitro de la moxifloxacine (8-méthoxyquinolone) seule ou en association avec le céfotaxime sur les streptocoques du groupe B.

AIM OF THE STUDY: Our objective is to determine in vitro efficiency of moxifloxacin (MXF) alone or in combination with cefotaxime (CTX) on Group B streptococcus (GBS). MATERIALS AND METHODS: For 21 strains of GBS isolated from newborn invasive infections (6 meningitis and 15 bacteraemia), the bacterial growth in Mueller Hinton broth with MXF and/or CTX leaded to the determination of MIC and MBC, the determination of tolerance for CTX and the evaluation of the bacteriostatic action of these antibiotics combination by calculating the FIC index. Time-kill studies were conducted for MXF and CTX alone or in combination for the first four hours, with concentrations likely reached in CSF. RESULTS: Study of GBS growth with crossed concentrations of MXF and CTX showed no resistant strains, no tolerant strains, and no antagonism between MXF and CTX. Killing curves demonstrated that MXF is ten-fold more active than CTX in the first four hours. DISCUSSION: MXF is an interesting antibiotic for its good activity on the GBS, suggesting that MXF is a good candidate for further evaluation in GBS meningitis in animal model.

[Evaluation of four immunoenzymatic tests for detecting Clostridium difficile toxins A and B]. / Evaluation de quatre réactifs immunoenzymatiques pour la recherche des toxines A et B de Clostridium difficile.

Four immunoenzymatic tests for detecting Clostridium difficile toxins A and B were studied: two rapid tests (Tox A/B QUIK CHEK-Techlab and NoviView Toxine-A-Hiss diagnostics) and two Elisa tests (C. difficile TOX A/B II -Techlab and Toxin A+B Elisa Test, Novitec-Hiss diagnostics). The results were compared to those obtained with ImmunoCard Tox A+B -ICTAB (Meridian), C. difficile Toxine A (Oxoid) for rapid test and Elisa Premier A+B Meridian for Elisa. A total of 41 stools and 16 isolates were studied with rapid tests. On stools, the sensitivity and specificity of QUIK CHEK test was 94.1% and 100% respectively compared to the test ICTAB. On the isolates, sensitivity and specificity was 100%. With the Noviview test, the sensitivity on stools and isolates was respectively 88.2 and 85.7% and the specificity was 100% compared to Oxoid. A total of 38 stools were studied with Elisa tests. With Techlab test compared to the test Premier, sensitivity and specificity was 100%. The Novitec test gave five false negative reactions with consequently a sensitivity of 70.6%.

[Peritoneal tuberculosis: 27 cases in the suburbs of northeastern Paris]. / Tuberculose péritonéale: 27 cas dans la banlieue nord-est de Paris.

SETTING: Peritoneal tuberculosis did not disappear from France during the 1990s. OBJECTIVE: To determine the characteristics of peritoneal tuberculosis in the north-eastern suburbs of Paris. METHOD: A retrospective study of cases diagnosed with peritoneal tuberculosis between 1990 and 1998 in five suburban hospitals in the north-east region of Paris. RESULTS: Twenty-seven cases of adult peritoneal tuberculosis were diagnosed. There were nine women and 18 men, with a mean age of 37.5 years, 88.9% of whom were foreign born. General and digestive symptoms--abdominal pain and/or ascites--were present in 96.3% of the cases. The mean delay in treatment was 30 days. Peritoneal involvement was isolated in 25.9% of cases, and associated with pulmonary tuberculosis in 40.7% or hepatic tuberculosis in 25.9%. Co-infection with HIV (human immunodeficiency virus) was present 14.8% of cases. Culture of ascites fluid, laparoscopy and/or laparotomy (n = 17), with directed biopsy, aided in the formal diagnosis of peritoneal tuberculosis in 59.2%. One relapse and one case of multiresistance were observed. The mean duration of treatment was 9 months (range 6-12 months). Three patients received treatment with corticosteroids, and 91.2% of the patients achieved cure without sequelae. CONCLUSION: Peritoneal tuberculosis is not rare in the Paris region. The diagnosis should be suspected in case with ascites and fever, and can be confirmed by laparoscopy with sampling for bacteriology and histology. The methods of treatment need to be standardised.

Effects of isoflurane on bacterial growth.

Anaesthetic agents have been implicated in the development of postoperative pneumonia, but the direct effect of volatile anaesthetics on bacterial growth has given contradictory results. The effects of isoflurane on the growth of Staphylococcus aureus and Escherichia coli were investigated under conditions similar to those of clinical practice, using standardized microbiological methods. An open anaesthetic circuit was adjusted to the normal ventilatory settings of an adult patient. A spray, installed on the inspiratory side of the circuit, ensured the delivery of isoflurane at 1.5 minimal alveolar concentration. The bacterial strains studied were both wild-type and reference strains. Bacterial inoculums were prepared to obtain a bacterial exponential growth of 10(3) colony-forming units per mL in 10 mL of nutritive broth. Each strain was studied with and without exposure to isoflurane and measured by the usual criteria of bacterial growth, and by bacterial regrowth after exposure to isoflurane. Under experimental conditions close to clinical practice, exposure to isoflurane did not alter bacterial growth of S. aureus and E. coli, or their bacterial regrowth when isoflurane exposure is over.

Extrapulmonary tuberculosis in the northeastern suburbs of Paris: 141 cases.

Background: Big cities were particularly affected by tuberculosis in the 1990s. Methods: We studied 141 cases of extrapulmonary tuberculosis in patients not infected by HIV in the northeastern suburbs of Paris. Results: A total of 84 men and 57 women were included in the study. Their average age at diagnosis was 42.2 years. Some 73.6% of the patients were foreign-born. A total of 182 sites were identified in 141 patients. There was an association with pulmonary tuberculosis in 38 cases. The sites were: lymph node (48.9%), pleural (25.5%), skeletal (22.7%), genitourinary (5.7%), and meninges (5%). Unfavorable social conditions were frequently observed. The average duration of treatment was 10 months. Twenty-four adverse drug effects were noted. Sixty-eight strains of Mycobacterium tuberculosis were isolated. Five cases of primary resistance to at least one antituberculous drug and only one case of multidrug resistance were observed. Some 95.7% of the 93 patients who were not lost to follow up were cured. Conclusion: Independently of HIV infection, extrapulmonary tuberculosis is still present, particularly in the suburbs of big cities, where social conditions are poor. The significant number of patients lost to follow-up demands that measures be adapted for the therapeutic management of these patients.

Antibody-based enzyme-linked immunosorbent assay for determination of anti-PGL-I specific circulating immune complex in leprosy patients.

A serological study was performed in 122 individuals: 75 leprosy patients and 47 healthy controls. The ELISA test was performed for IgG and IgM using the glycolipid PGL-I antigen from Mycobacterium leprae. Circulating immune complexes (CIC) were isolated by PEG 6000 precipitation method and after dissociation with an acid solution, the IgG and IgM specific against PGL-I were tested with the ELISA test. The multibacillary patients had high levels of antibodies, compared with paucibacillary patients and controls. The antibodies isolated from the CIC presented a similar spectrum spectral distribution as the serology. A positive correlation between the levels of free and CIC bound antibodies was observed. In contrast with tuberculosis patients, specific antibodies present in CIC were not responsible for false-negative results found in some multibacillary patients' serology, since no or very low levels of specific antibodies were found in PEG precipitated serum of these patients. No relation was observed with specific antibody levels detected in CIC during leprosy reactions.

Anti-phenolic glycolipid-I (PGL-I) determination using blood collection on filter paper in leprosy patients.

The authors studied 70 leprosy patients and 20 normal individuals, comparing the traditional sera collection method and the finger prick blood with the conservation on filter paper for specific antibodies against the native phenolic glycolipid-I (PGL-I) from Mycobacterium leprae. The finger prick blood dried on filter paper was eluated in phosphate buffer saline (PBS) containing 0.5% gelatin. The classical method for native PGL-I was performed for these eluates, and compared with the antibody determination for sera. It was observed that there is a straight correlation comparing these two methods; although the titles found for the eluates were lower than those obtained for serology. This blood collection method could be useful for investigation of new leprosy cases in field, specially in contacts individuals.

[Susceptibility of Clostridium difficile to metronidazole using the E-test: effect of the culture medium]. / Sensibilité de Clostridium difficile au métronidazole par le E-test: influence du milieu de culture.

The treatment of intestinal Clostridium difficile infections rests on administration of either a glycopeptide or metronidazole. Given the current shifts in resistance patterns of anaerobes to antimicrobials, a study of the susceptibility of C. difficile to metronidazole was timely. The objective of this study was to evaluate the influence of the culture medium on the Minimal Inhibitory Concentration (MIC) of metronidazole as determined using the E-test. Thirty-one strains were grown on three different media supplemented with 5% horse blood, namely Columbia agar, Wilkens Chalgren agar, and Brucella agar. Results were compared to those obtained using the reference agar dilution method (ADM). As recommended by the French Society for Microbiology, susceptibility was defined as an MIC < or = 4 mg/L. When used on strains susceptible by the ADM, the E-test yielded lower values than the ADM with all three media. Furthermore, findings suggest that E-test results obtained with strains whose MIC is in the 4 to 8 mg/L range by the ADM should be interpreted with caution and, in some cases, tested using the ADM.

Bacterial contamination of pneumoperitoneum gas in peritonitis and controls: a prospective laparoscopic study.

There is a theoretical risk that the pneumoperitoneum gas could carry bacteria in aerosol form and spread infection throughout the peritoneal cavity during laparoscopy for infective conditions such as appendicitis. The aim of this study was to attempt to culture bacteria from the pneumoperitoneum gas during laparoscopy for potentially infected cases and a group of controls. A total of 53 consecutive laparoscopies were studied, of which 21 were potentially infected and 32 served as controls. A lavage of the operative site was positive for pathogenic bacteria in almost 30% of the potentially infected group and only 3% of the control group. The pneumoperitoneum gas was bubbled through blood culture medium at the beginning and the end of the procedure, but only one of the 106 bottles grew any bacteria, and the specimen was a likely contaminant. In conclusion, we were unable to grow any significant bacteria from any of our cases despite using a sensitive method and demonstrating pathogenic bacteria in the peritoneal lavages. The pneumoperitoneum itself is unlikely to disperse bacteria.

An epidemic of tuberculosis with a high rate of tuberculin anergy among a population previously unexposed to tuberculosis, the Yanomami Indians of the Brazilian Amazon.

A survey of an emerging tuberculosis epidemic among the Yanomami Indians of the Amazonian rain forest provided a unique opportunity to study the impact of tuberculosis on a population isolated from contact with the tubercle bacillus for millennia until the mid-1960s. Within the Yanomami population, an extraordinary high prevalence of active tuberculosis (6.4% of 625 individuals clinically examined) was observed, indicating a high susceptibility to disease, even among bacille Calmette-Guérin-vaccinated individuals. Observational studies on cell-mediated and humoral immune responses of the Yanomami Indians compared with contemporary residents of the region suggest profound differences in immunological responsiveness to Mycobacterium tuberculosis infection. Among the Yanomami, a very high prevalence of tuberculin skin test anergy was found. Of patients with active tuberculosis, 46% had purified protein derivative of tuberculosis reactions <10 mm; similarly 58% of recent bacillus Calmette-Guérin vaccines exhibited skin test reactions <5 mm. The Yanomami also had higher titers of antibodies against M. tuberculosis glycolipid antigens (>70%) than the control subjects comprised of Brazilians of European descent (14%). The antibodies were mostly of the IgM isotype. Among the tuberculosis patients who also produced IgG antibodies, the titers of IgG4 were significantly higher among the Yanomami than in the control population. Although it was not possible to analyze T-cell responses or patterns of lymphokine production in vitro because of the remoteness of the villages from laboratory facilities, the results suggest that the first encounter of the Yanomami Indian population with tuberculosis engenders a diminished cell-mediated immune response and an increased production antibody responses, relative to other populations with extensive previous contact with the pathogen. These findings suggest that tuberculosis may represent a powerful selective pressure on human evolution that over centuries has shaped the nature of human immune responses to infection.

[Does laparoscopic treatment of abdominal infections generate bacteremias? Prospective study: 75 cases]. / Le traitement laparoscopique des infections abdominales génère-t-il les bactériémies? Etude prospective: 75 cas.

Laparoscopy is increasingly used in conditions complicated by peritonitis. A theoretical concern is that carbon dioxide pneumoperitoneum may increase bacteraemia. In a prospective study 90 patients were treated by laparoscopic appendicectomy. 30 of them had no histological abnormality; 30 had an acute appendicitis and 30 an acute peritonitis. 75 patients were eligible for the study. The treatment protocol (surgery-antibiotherapy) was the same for the 3 groups. All patients had blood cultures before, during and after insufflation of CO2 in the peritoneum, and bacterial examination of the operative site. Septic morbidity was evaluated for each patients. Positive bacterial culture from abdominal site are correlated with the pathologic findings. There were no positive blood cultures in the groups studied and no incidence in term of septic morbidity. This study suggests that laparoscopic treatment of septic abdominal diseases does not facilitate bacteriemias and does no affect septic morbidity.