Evaluación del método de Petroff modificado con solución salina para el diagnóstico de micobacterias en el sistema Bact/Alert 3D / Assessment of Petroff method modified with saline solution for the diagnosis of mycobacteria in Bact/Alert 3D system

Introducción: Existen diferentes métodos de descontaminación de muestras pulmonares para el diagnóstico de micobacterias. El Programa Nacional de Control de Tuberculosis recomienda el método de Petroff modificado con solución salina, pero no existen evidencias documentadas que avalen este método. Objetivo: Evaluar el método de Petroff modificado con solución salina para el diagnóstico de micobacterias en el sistema Bact/Alert 3D. Métodos: Se realizó un estudio observacional analítico de pruebas diagnósticas utilizando 100 muestras pulmonares recibidas en el Laboratorio Nacional de Referencia e Investigaciones de Tuberculosis, Lepra y Micobacterias del Instituto Pedro Kourí, abril 2016 enero 2017. La muestra se dividió en 3 alícuotas y se descontaminaron mediante 3 métodos; luego se inocularon en los medios de cultivo sólido y líquido. Se compararon los resultados del cultivo en cuanto: tiempo de detección de crecimiento, tasa de contaminación, por ciento de positividad, además se calcularon indicadores de desempeño. Resultados: Al comparar el método Petroff modificado con solución salina con el Petroff modificado con solución fosfato en Löwenstein Jensen, el tiempo de detección de crecimiento, por ciento de positividad y la tasa de contaminación se comportaron de forma similar y la sensibilidad (93,75 por ciento), concordancia (96,47 por ciento) e índice de Youden (0,91) fueron elevadas. Al compararlo el Petroff modificado con solución salina con el N-Acetil-L-Cisteína, las variables no mostraron diferencias significativas y los Indicadores de Desempeño se comportaron por encima del 93 por ciento, para el medio sólido y líquido. Conclusiones: Los resultados avalan la continuidad del uso del Petroff modificado con solución salina como método de descontaminación de las muestras pulmonares en la red de laboratorios de Cuba y como alternativa en el pretratamiento de las muestras para el medio líquido (Bact/Alert 3D), además constituye un soporte para el Programa Nacional de Control de Tuberculosis(AU)

Introduction: There are different decontamination methods of pulmonary samples for the diagnosis of mycobacteria. The National Program for the Control of Tuberculosis recommends Petroff method modified with saline solution; but there are not documented evidences that endorse it. Objective: Assess Petroff method modified with saline solution for the diagnosis of mycobacteria in Bact / Alert 3D system. Methods: An observational analytic study of diagnostic tests was conducted; there were used 100 pulmonary samples received in the National Laboratory of References and Researches of Tuberculosis, Leprosy and Mycobacteria of Pedro Kourí Institute, from April 2016 to January 2017. The sample was divided in 3 aliquots and those were decontaminated using 3 methods; then, they were inoculated in the solid and liquid culture means. Cultures´ results were compared according to: growth's detection time, contamination rate, percent of positivity; in addition, performance indicators were calculated. Results: When comparing Petroff method modified with saline solution with Petroff method modified with phosphate solution in Löwenstein Jensen, the growth's detection time, the percent of positivity and the rate of contamination behaved similarly, and sensitivity (93,75percent), concordance (96,47percent) and Youden´s index (0,91) were high. When the Petroff method modified with saline solution was compared with N-Acetil-L- Cisteina, the variables did not show significative differences and the behaviour indicators were over 93percent for the solid and liquid mean. Conclusions: The results endorse the continuity of the use of Petroff method modified with saline solution as a decontamination method of pulmonary samples in the network of Cuban laboratories and as alternative to the pre-treatment of the samples for the liquid mean (Bact/Alert 3D); it also constitutes a support for the National Program for the Control of Tuberculosis(AU)

Evaluation of BacT/Alert FAN Plus Bottles for the Culture of Peritoneal Dialysate / 대한임상미생물학회지

BACKGROUND: A major complication of peritoneal dialysis (PD) is peritonitis, and bacterial culture of PD effluent in a blood culture bottle is the preferred technique for diagnosis of peritonitis. In this study, we compared dialysate inoculation and culture using the BacT/AlerT® Fastidious Antimicrobial Neutralization Plus blood culture bottles (FAN Plus; bioMérieux, France) to the conventional centrifugation culture method.METHODS: A total of 170 PD effluents were simultaneously processed by the conventional centrifugation culture method and by culture using FAN Plus media with two different inoculation procedures: inoculation after centrifugation and direct bedside inoculation.RESULTS: Of the 52 cultures that were positive on at least one of the culture methods, 27 samples were positive on conventional centrifugation. However, 46 samples showed growth following inoculation into the FAN Plus media after centrifugation, and 47 samples were positive on the direct FAN Plus inoculation method. Using the case definition for PD peritonitis to classify samples, sensitivity of the conventional method was 50.0% (95% CI, 33.7–66.3%), whereas the sensitivity of the FAN Plus media was 78.9% (95% CI, 62.2–89.9%) by inoculation after centrifugation and 86.8% (95% CI, 71.1–95.1%) by direct inoculation. Use of both inoculation methods with FAN Plus media resulted in 92.1% sensitivity (95% CI, 89.2–99.9%).CONCLUSION: Culture using FAN Plus media demonstrated a superior bacterial recovery rate to the conventional centrifugation culture method. A combination of the two inoculation methods with FAN Plus media is recommended for the best diagnostic yield, while direct inoculation alone can be useful due to its simplicity and cost-effectiveness.

Isolation, Identification and Drug Resistance Testing of Mycobacterium tuberculosis by Recent Diagnostic Modalities at Teaching Hospital in Moradabad (UP).

Objective: Tuberculosis is the second leading cause of death in developing countries among all infectious diseases. Globally, drug resistance strain of Mycobacterium tuberculosis is a public threat. Due to diagnostic delay, inadequate infection control and poor drug supply there is a emergence of MDR- TB and XDR- TB. Our aim was to isolate and identify the drug resistant strain of M. tuberculosis by using newer diagnostic modalities. Methods: Sputum sample and BAL fluid from 70 suspected cases were collected and analysed for Mycobacterium by Ziehl – Neelsen staining and liquid culture with molecular detection of drug resistant strain of M. tuberculosis. Result: In our study, among the 70 patients 27 (38.5%) were positive for AFB by microscopy. On testing for Mycobacterium by BacT/Alert 3D system, 54 were found to be positive. On performing further identification and susceptibility of 54 isolates towards rifampicin and isoniazid by molecular method, 5 isolates (9.25%) were resistant to both rifampicin and isoniazid confirming as multidrug resistant. 5 isolates (9.25%) were sensitive to rifampicin and resistant to isoniazid and 2 isolates (3.70%) were resistant to rifampicin and sensitive to isoniazid. Whereas 5 isolates (9.25%) found to be negative for M. tuberculosis. Conclusion: Our investigation highlights the importance of newer diagnostic modalities for isolation and identification of drug resistant strain of M. tuberculosis. Which ensure early and accurate diagnosis of patients with prevention of further transmission of disease.

Comparación del sistema BacT/ALERT® 3D con los métodos de cultivo Lowenstein-Jensen y Ogawa-Kudoh para el aislamiento de micobacterias / Comparison of BacT/ALERT 3D® system with the culture methods of Lowenstein-Jensen and Ogawa-Kudoh, for the isolation of mycobacteria

La tuberculosis es una enfermedad causada por bacterias pertenecientes al Complejo Mycobacterium tuberculosis. El diagnóstico se dificulta por su sintomatología inespecífica y los métodos bacteriológicos que ofrecen resultados tardíos. El objetivo del presente estudio fue comparar el desempeño del sistema automatizado BacT/ALERT® 3D con los métodos convencionales de cultivo en medio Lowenstein-Jensen (L-J) y Ogawa-Kudoh (O-K) para el aislamiento de micobacterias. Se procesaron 266 muestras provenientes de pacientes con sospecha de tuberculosis entre mayo y octubre de 2013. Se aislaron 63 bacilos acido-resistentes: 46 M. tuberculosis y 17 micobacterias no tuberculosas (MNT). Al comparar los tres métodos, se observó que todos presentaron desempeño similar en el aislamiento de M. tuberculosis. Las tasas de recuperación obtenidas no mostraron diferencia estadísticamente significativa (p>0,05) sin embargo, con BacT/ALERT® 3D se aislaron mayor número de MNT, con diferencia significativa respecto al L-J (p<0,05). El tiempo de detección promedio de M. tuberculosis fue de 11 días por BacT/ALERT® 3D, 20 días en L-J y 23 días en O-K. La contaminación cruzada, fue de 0,38%. Se concluyó que BacT/ALERT® 3D es una excelente herramienta para el aislamiento de M. tuberculosis, mejora la recuperación de las MNT y reduce significativamente el tiempo de diagnóstico, lo que permitiría un tratamiento oportuno, con mayor probabilidad de sobrevida del paciente.

Tuberculosis is a disease caused by species of the Mycobacterium tuberculosis complex. The diagnosis is difficult due to nonspecific symptoms and late results of bacteriological culture methods. The aim of this study was to compare the efficiency of the BacT/ALERT® 3D automated system with conventional methods of culture on Lowenstein-Jensen (L-J) and Ogawa-Kudoh (O-K). A total of 266 specimens from patients with clinical suspected tuberculosis were studied from May to October 2013. We recovered, 63 acid fast bacilli isolates: 46 identified as M. tuberculosis and 17 as nontuberculous mycobacteria (NTM). The three methods had a similar performance for isolation of M. tuberculosis; recovery rates obtained showed no statistically significant difference (p> 0.05). However, with the BacT/ALERT® 3D system, a larger number of MNT were isolated, with significant statistic difference for L-J (p <0.05). The average detection time for M. tuberculosis was 11 days with the BacT/ALERT® 3D system, with significant statistic difference for LJ (20.4 days) and O-K (23.2 days). Additionally, cross-contamination was determined as 0.38%. The study results showed that the BacT/ALERT® 3D system is an excellent tool for isolation of M. tuberculosis and it improves the recovery of NTM. Also, the time of diagnosis is significantly reduced, leading to earlier treatment that could improve patient recovery.

Nuevas herramientas para el diagnóstico de la tuberculosis / New tools for tuberculosis diagnosis

Introducción: en las últimas décadas se han desarrollado nuevas herramientas para disminuir el tiempo de diagnóstico de las infecciones por Mycobacterium tuberculosis. Objetivo: introducir nuevas herramientas para la identificación de M. tuberculosis y comparar los resultados con el cultivo en Löwenstein Jensen. Métodos: se estudiaron 1 368 muestras recibidas en el Laboratorio Nacional de Referencia de Tuberculosis del Instituto de Medicina Tropical Pedro Kourí, de agosto 2010 - agosto 2014. Las muestras después de procesadas fueron inoculadas en paralelo en Löwenstein Jensen y en BacT ALERT. Los resultados se ana­lizaron y compararon con relación al total de aislamientos, tiempo de detección de crecimiento y tasa de contaminación, se calcularon además los indicadores de desempeño del BacT ALERT. Resultados: por Bact/ ALERT se identificó Mycobacterium tuberculosis en 126 (98,5 por ciento) muestras y 116 (88,5 por ciento) por el Löwenstein Jensen. El tiempo de detección de crecimiento de Mycobacterium tuberculosis por el BacT/ ALERT fue de 16,6 días, dos veces menor que el obtenido por el Löwenstein Jensen (35,5 días). La tasa de contaminación por el Bact/ ALERT y Löwenstein Jensen fue de 11 por ciento y 7,8 por ciento, respectivamente. La sensibilidad, especificidad e índice de Youden fue de 99,1 por ciento, 99,0 por ciento y 0,98, respectivamente; y el índice de validez del 99 por ciento. Conclusiones: el sistema Bact/ ALERT resultó un método útil porque acortó significativamente el tiempo de diagnóstico de la tuberculosis permitiendo comenzar el tratamiento de forma oportuna, sobre todo en pacientes con baciloscopia negativa. El uso combinado del Löwenstein Jensen y medio líquido aseguró la recuperación del total de cepas de M. tuberculosis(AU)

Background: in recent decades, new tools have been developed to decrease the time of diagnosis of infections with Mycobacterium tuberculosis. Objective: to introduce the new tools for identification of M. tuberculosis and compare the results with culture in Löwenstein Jensen. Methods: 1 368 samples received at the National Tuberculosis Reference Laboratory of the IPK from August 2010 to August 2014. After samples processed were inoculated in parallel on Löwenstein Jensen and BacT ALERT. The results obtained are analyzed and compared with respect to the total isolates, time detection of growth and contamination rate, the performance indicators of BacT ALERT also calculated. Results: by Bact / ALERT were identified Mycobacterium tuberculosis in 126 (98.5 percent) samples and 116 (88.5 percent) by Löwenstein Jensen. The time detection of growth of Mycobacterium tuberculosis by BacT / ALERT was 16.6 days, two times lower than that obtained by the Löwenstein Jensen (35.5 days). The contamination rate by Bact / ALERT and Löwenstein Jensen was 11 percent and 7.8 percent, respectively. The sensitivity, specificity and Youden index was 99.1 percent, 99.0 percent and 0.98, respectively; and the validity index was 99 percent. Conclusions: bact / ALERT system proved a useful method because it significantly shortened the time of tuberculosis diagnosis and start allowing treatment in a timely manner, especially in smear-negative patients. The combined use of liquid medium and Löwenstein Jensen assured recovery of all strains of Mycobacterium tuberculosis(AU)

A study on application of BacT/ALERT 3D liquid culture technology on tuberculosis drug resistance detection / 预防医学

Objective To evaluate the BacT/ALERT 3D liquid culture technology on the detection of drug resistance of Mycobacterium tuberculosis(MTB)and to compare the difference between this technology and Lowenstein -Jensen (L -J) proportion method.Methods BacT/ALERT 3D liquid culture technology and L -J proportion technology were applied to detect the drug resistance of tuberculosis from the positive cultures of 219 solid culture samples.Results The average detection time of BacT/ALERT 3D method was 8.02 ±3.85 d,which was about 20 days shorter than that of L -J proportion method.60 drug resistance strains were found using BacT/ALERT 3D technology,While 79 drug resistance strains were found using L -J proportion technology.There showed no significant difference (P >0.05).The compliance rate of BacT/ALERT 3D method and L -J proportion method on the anti -tuberculosis drugs INH,RFP,EMB and SMwas 95.43%,92.69%,95.43% and 92.24% respectively.Conclusion BacT/ALERT 3D liquid culture technology could detect drug resistant TB strains rapidly with high concordance with the results of L -J proportion method on anti -tuberculosis drugs.

The effect evaluation on the application of BacT/ALERT 3 D technique for the fast cultivation of mycobacterium tuberculosis / 预防医学

Objective To evaluate the BacT/ALERT 3D liquid rapid culture system for the rapid detection of mycobacterium tuberculosis(MTB)and early diagnosis of pulmonary tuberculosis.Methods BacT/ALERT 3D liquid culture mediums and lowenstein-jensen(L-J)solid culture mediums were applied to detect Mycobacterium tuberculosis sputum specimens respectively.Analysis of detection results and detection time were also performed.Results Average positive days of BacT/ALERT 3D liquid culture medium was(13 ±2.05)days,which was shorter than that of L-J solid culture mediums(34.7 ±4.76 )d (P<0.05 ).Compared to the L -J solid culture mediums,BacT/ALERT 3D liquid culture medium had higher positive rate for 59 patients whose sputum smear test was positive,and the positive rate were 71.18%(42/59)and 67.80%(40/59)respectively(P<0.05).BacT/ALERT 3D liquid culture medium had higher positive rate than L-J solid culture mediums for 106 patients whose sputum smear test was negative,and the positive rate were 39.62%(42/106)and 26.42%(28/106)respectively(P<0.05).Conclusion Compared to the traditional L-J solid culture system,BacT/ALERT 3D liquid culture system can shorten detection time and improve the positive detection rate of MTB in specimens with low concentration.

Comparison of Methods for Detecting Bacterial Contamination in Platelet Concentrates / 대한수혈학회지

BACKGROUND: Bacterial contamination of platelets represents the highest infectious risk for a transfusion. In this study, we evaluated 2 culture-based systems that have been approved by the US FDA for bacterial screening. METHODS: Platelet concentrates were inoculated with 5 bacterial species to give a final concentration of 10(0), 10(1) and 10(2) CFU/mL. Samples for culture were taken immediately after inoculation (0 hr sample) and after 24 hrs (24 hr sample). For the BacT/ALERT 3D system, a 10 mL sample was inoculated into an aerobic culture bottle and incubated for 7 days. For the Pall eBDS system, 3 mL samples were taken from the 0 hr and 24 hr samples, respectively. The samples were incubated for 24 hrs and 30 hrs. RESULTS: Both systems detected all inoculated units both in the 0 hr and 24 hr samples, except for units inoculated with K. pneumoniae. Eleven units out of 30 units inoculated with K. pneumoniae were detected by the BacT/ALERT 3D system in the 24 hr samples. The Pall eBDS system detected 8 of 30 units in the 24 hr samples. CONCLUSION: Implementation of either system will decrease the risk of transfusing bacterially contaminated platelets. However, testing for bacterial contamination will not completely prevent septic transfusion reactions; pathogen inactivation that is now available should also be considered as an alternative method to reduce the risk of bacterial contamination.

Standardization of first and second-line antitubercular susceptibility testing using BacT Alert 3D system: a report from a tertiary care centre in India

Resurgence of multidrug resistant tuberculosis has lead to demand for rapid susceptibility testing. Conventional methods take > 3 weeks and are tedious. Automated methods have superseded them for first line drug susceptibility testing. An attempt was made to standardize first and second line susceptibility testing using the BacT Alert 3D system (Biomerieux). And compare results with Lowenstein Jensen's (LJ) method. 121 isolates of Mycobacterium tuberculosis, 67 pulmonary and 54 extra pulmonary were subjected to sensitivity to first and second line drugs. Multidrug resistance was detected equally by both methods at 15.7 percent. 100 percent agreement was observed between the two methods for aminoglycosides, rifampicin, ethionamide and ciprofloxacin. 91.5 percent agreement was observed for isoniazid, 85 percent for pyrazinamide and 72.4 percent for ethambutol. The time taken by LJ method was 18-32 days and BacT Alert 3D system took 4-12 days. In the lesser developed nations where tuberculosis is rampant a rapid effective method for confirming multidrug resistant tuberculosis is definitely desirable and the BacT Alert 3D system was found an effective method when compared to the 'gold standard' LJ proportion.

Effect of Delayed Entry into 2 Different Blood Culture Systems(BacT/Alert 3D and BACTEC 9120) on Culture Positivity / 中华医院感染学杂志

OBJECTIVE To evaluate the effect of delayed entry(0-24 h) into BacT/Alert 3D and BACTEC 9120 and the effect of 2 incubation temperatures(22 ℃ vs 35 ℃) on culture positivity.METHODS We utilized the BacT/Alert system with FA bottles and the BACTEC 9120 system with Plus(Aerobic) bottles.Four clinical bacterial species,Staphylococcus aureus,Escherichia coli,Streptococus pneumoniae,Candida albicans,were used as the test strains.and 5 ml of blood were added to each bottle.Each species was inoculated into the bottles 3 times at an inoculum size of 10 CFU/ml,102 CFU/ml and 108 CFU/ml,respectively.The inoculated bottles were cultured using the respective instruments after they were allowed to stand at room temperature(22 ℃)and 35 ℃ for 0,8,16 and 24 h.Time-to-detection and culture positivity were evaluated.RESULTS The delay in transportation of blood culture bottles stored at room temperature(22 ℃) or 35 ℃ had no effect on the recovery rate for BACTEC 3D at less than 24 h preincubation time and for BacT/Alert 9120 at less than 16h preincubation time.The positivity rate decreased significantly for BacT/Alert 9120 for 24 h of delay.Culture positivity of BacT/Alert 3D was higher than BACTEC 9120 for 24 h of delay.CONCLUSIONS The delayed entry for BacT/Alert 3D should be within 24 h,but the delayed entry for BACTEC 9120 should be within 16 h.

Evaluation of FAN-aerobic Blood Culture Bottle in BacT/Alert3D System / 대한임상미생물학회지

BACKGROUND: This study was designed to evaluate the performance of FAN-aerobic bottles (FANA) in comparison with standard-aerobic bottles (STD-A) in BacT/Alert3D blood culture system. METHODS: A total of 596 pairs of blood cultures, submitted from Emergency Department of Pusan National University Hospital between July and December 2004, were evaluated. In addition to the routine blood culture protocol using standard blood culture bottles, 5 ml of blood samples was inoculated into FAN-A bottles for this study. RESULTS: Microorganisms were grown in 84 (14.1%) of 596 cultures; of those, 15 were positive in STD-A only (2.5%), 35 in FAN-A only (5.9%), and 34 in both (5.7%). The positive rate in FAN-A bottles was significantly higher than that in STD-A bottles (P<0.001). The species of isolates and detection time showed no difference between the blood culture bottles. CONCLUSION: In the BacT/Alert3D blood culture system, the use of FAN-A bottles instead of the standard aerobic bottles should yield a higher positive rate.

Detection of bacterial contamination with BacT/ALERT 3D in cord blood bank / 中国输血杂志

Objective To define a suitable and adequate sample volume for the detection of bacterial contamination in cord blood (CB) via BacT/ALERT system. Methods A total of 1 376 cord blood units were routinely screened for aerobic and anaerobic microorganisms by culturing the erythrocyte fraction(EF) or plasma fraction(PF) with 20 ml and 10 ml sample volume. The microbial contamination was detected by BacT/ALERT 3D system, and the results of this method were compared with the improved Martin/thiogly collate broth(22 ℃) and thioglycollate broth(35 ℃).Results The rates of positive BacT/ALERT results were 1.16%(10 ml) and 1.24%(20 ml) for PF, and 3.20%(20 ml) for EF. The positive rate of Martin/thiogly collate broth(22 ℃/35 ℃) was 1.00% for EF. Conclusion Using BacT/ALERT system for microbial detection in cord blood bank can enhance the security of umbilical cord blood transplantation.