Head-to-head comparison of CAMPYAIR aerobic culture medium versus standard microaerophilic culture for Campylobacter isolation from clinical samples.

Campylobacter spp. are considered the most frequent cause of acute gastroenteritis worldwide. However, outside high-income countries, its burden is poorly understood. Limited published data suggest that Campylobacter prevalence in low- and middle-income countries is high, but their reservoirs and age distribution are different. Culturing Campylobacter is expensive due to laboratory equipment and supplies needed to grow the bacterium (e.g., selective culture media, microaerophilic atmosphere, and a 42°C incubator). These requirements limit the diagnostic capacity of clinical laboratories in many resource-poor regions, leading to significant underdiagnosis and underreporting of isolation of the pathogen. CAMPYAIR, a newly developed selective differential medium, permits Campylobacter isolation without the need for microaerophilic incubation. The medium is supplemented with antibiotics to allow Campylobacter isolation in complex matrices such as human feces. The present study aims to evaluate the ability of the medium to recover Campylobacter from routine clinical samples. A total of 191 human stool samples were used to compare the ability of CAMPYAIR (aerobic incubation) and a commercial Campylobacter medium (CASA, microaerophilic incubation) to recover Campylobacter. All Campylobacter isolates were then identified by MALDI-TOF MS. CAMPYAIR showed sensitivity and specificity values of 87.5% (95% CI 47.4%-99.7%) and 100% (95% CI 98%-100%), respectively. The positive predictive value of CAMPYAIR was 100% and its negative predictive value was 99.5% (95% CI 96.7%-99.9%); Kappa Cohen coefficient was 0.93 (95% CI 0.79-1.0). The high diagnostic performance and low technical requirements of the CAMPYAIR medium could permit Campylobacter culture in countries with limited resources.

Diagnostic value of pediatric blood culture bottles for acute postoperative endophthalmitis.

OBJECTIVE: To report our experience using conventional culture methods (CM) and pediatric blood culture bottles (PBCBs) for vitreous sample culture of acute postoperative endophthalmitis. METHODS: A retrospective study was conducted at the Department of Ophthalmology, Hospital das Clinicas, HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, BR, from January 2010 to December 2015, and it included 54 patients with clinically suspected acute postoperative endophthalmitis. Vitreous samples were obtained by vitreous tap or vitrectomy. Samples from January 2010 to December 2011 were cultivated in CM, whereas samples from January 2012 to December 2015 were inoculated in PBCBs. The measured outcome was the yield of positive cultures. RESULTS: Twenty cases were included in the CM group, and 34 cases were included in the PBCB group. The yield of positive cultures in PBCBs (64.7%) was significantly higher than that in conventional CM (35%, p=0.034). Staphylococcus epidermidis and Streptococcus viridans were the two most commonly found agents. CONCLUSION: PBCBs can be used successfully in clinically suspected endophthalmitis. The method showed a higher yield of positive cultures than the conventional method. This technique appears to have several advantages over the traditional method: it saves time, as only one medium needs to be inoculated; transportation to a laboratory is easier than in the traditional method, and there is no need to maintain a supply of fresh agar media. The use of PBCBs may be recommended as the primary method for microbiological diagnosis and is especially suitable for office settings and remote clinics.

Diagnostic value of pediatric blood culture bottles for acute postoperative endophthalmitis

OBJECTIVE: To report our experience using conventional culture methods (CM) and pediatric blood culture bottles (PBCBs) for vitreous sample culture of acute postoperative endophthalmitis. METHODS: A retrospective study was conducted at the Department of Ophthalmology, Hospital das Clinicas, HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, BR, from January 2010 to December 2015, and it included 54 patients with clinically suspected acute postoperative endophthalmitis. Vitreous samples were obtained by vitreous tap or vitrectomy. Samples from January 2010 to December 2011 were cultivated in CM, whereas samples from January 2012 to December 2015 were inoculated in PBCBs. The measured outcome was the yield of positive cultures. RESULTS: Twenty cases were included in the CM group, and 34 cases were included in the PBCB group. The yield of positive cultures in PBCBs (64.7%) was significantly higher than that in conventional CM (35%, p=0.034). Staphylococcus epidermidis and Streptococcus viridans were the two most commonly found agents. CONCLUSION: PBCBs can be used successfully in clinically suspected endophthalmitis. The method showed a higher yield of positive cultures than the conventional method. This technique appears to have several advantages over the traditional method: it saves time, as only one medium needs to be inoculated; transportation to a laboratory is easier than in the traditional method, and there is no need to maintain a supply of fresh agar media. The use of PBCBs may be recommended as the primary method for microbiological diagnosis and is especially suitable for office settings and remote clinics.

Microorganisms in cryopreserved semen and culture media used in the in vitro production (IVP) of bovine embryos identified by matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS).

Commercial cattle breeders produce their own herd offspring for the dairy and beef market using artificial insemination. The procedure involves sanitary risks associated with the collection and commercialization of the germplasm, and the in vitro production and transfer of the bovine embryos must be monitored by strict health surveillance. To avoid the spreading of infectious diseases, one must rely on using controlled and monitored germplasm, media, and reagents that are guaranteed free of pathogens. In this article, we investigated the use of a new mass spectrometric approach for fast and accurate identification of bacteria and fungi in bovine semen and in culture media employed in the embryo in vitro production process. The microorganisms isolated from samples obtained in a commercial bovine embryo IVP setting were identified in a few minutes by their conserved peptide/protein profile, obtained applying matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS), matched against a commercial database. The successful microorganisms MS identification has been confirmed by DNA amplification and sequencing. Therefore, the MS technique seems to offer a powerful tool for rapid and accurate microorganism identification in semen and culture media samples.

Optimization of culture medium composition for manganese peroxidase and tyrosinase production during Reactive Black 5 decolourization by the yeast Trichosporon akiyoshidainum.

Decolourization and degradation of the diazo dye Reactive Black 5 was carried out by the yeast Trichosporon akiyoshidainum. A nine-factor Plackett-Burman design was employed for the study and optimization of the decolourization process and production of manganese peroxidase (MnP) and tyrosinase activities. In the present study, 26 individual experiments were conducted and three responses were evaluated. Raising yeast extract concentration significantly enhanced decolourization and MnP production. Carbon and nitrogen sources, glucose and (NH4)2 SO4, showed no significant effect on any response over the concentration range tested. Other culture medium components, such as CaCl2 or MgSO4, could be excluded from the medium formula, as they had no effect on the evaluated responses. Metal ions (Fe, Cu and Mn) showed different effects on decolourization and enzymatic activities. Addition of copper significantly enhanced MnP activity and decreased dye decolourization. On the contrary, iron had a positive effect on decolourization and no effect on enzyme production. Oddly, increasing manganese concentration had a positive effect on tyrosinase production without affecting decolourization or MnP activity. These results strongly suggest that dye decolourization should be regarded as a complex multi-enzymatic process, where optimal medium composition should arise as a compromise between those optimal for each implied enzyme production.

Selection and optimization of Bacillus atrophaeus inoculum medium and its effect on spore yield and thermal resistance.

Bacillus atrophaeus's spores are used as biological indicators to monitor sterilization processes and as a Bacillus anthracis surrogate in the development and validation of biosafety methods. The regular use of biological indicators to evaluate the efficiency of sterilization processes is a legal requirement for health services. However, its high cost hinders its widespread use. Aiming at developing a cost-effective inoculum medium, soybean molasses and nutrient-supplemented vinasse were evaluated for their effectiveness in solid-state fermentation (SSF). In biomass production, the results demonstrated that all tested compositions favor growth by providing the nutritional demands of the microorganism. Optimum casein peptone and soybean molasses concentration (1.0%, 2.5%, or 4.0%) was determined by a 2((2-0)) factorial experimental design. The results have showed a positive influence of peptone on biomass production. In order to define peptone final concentration (4.0% or 6.0%), a 2(2) factorial experimental design was used. An optimized medium containing 4.0% soybean molasses and 4.0% casein peptone was similar in performance to a synthetic control medium (tryptone soy broth) in dry-heat thermal-resistant spore production by SSF. An experiment performed under optimum SSF conditions resulted in 1.9 x 10(10) CFU g(-1) dry matter with D (160 degrees C) = 5.2 +/- 0.2 min.

Universal Collection Medium (UCM) is as suitable as the Standard Transport Medium (STM) for Hybrid Capture II (HC-2) assay.

BACKGROUND: Collection of cervical-vaginal material in liquid media enables simultaneous evaluation of both oncologic cytology and molecular tests for the detection of Human papillomavirus (HPV), Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG). Universal Collection Medium (UCM) has been developed to fulfill this objective. OBJECTIVES: To compare Hybrid Capture II (HC-2) to diagnose HPV, NG and CT in specimens collected in UCM and in the current Digene Standard Transport Medium (STM). STUDY DESIGN: The study was cross-sectional. Three collections of endocervical and ectocervical material were performed in each of 893 women referred for colposcopy in the following order: (1) to prepare a conventional Pap smear slide using the accompanying brush of the STM kit and with Ayre spatula; (2) for HC-2 test and liquid-based cytology using a 1 ml UCM vial as transport medium; material was collected with another similar brush; (3) for HC-2 test using a 1 ml STM vial as transport medium; material was collected with the same brush that we used in the procedure no. (1) (conventional Pap smear). HC-2 results from samples taken from STM and UCM media were compared by using simple linear regression analysis and Kappa statistic. RESULTS AND CONCLUSIONS: HC-2 results from the two media were highly correlated: high-risk HPV (kappa=0.92; r(2)=0.92), low-risk HPV (kappa=0.85; r(2)=0.86) and NG/CT (kappa=0.96; r(2)=0.81). Despite being obtained from a second specimen, the UCM HC-2 results were equivalent to those obtained with the standard medium STM and the UCM medium.

Microbiología en endocarditis infecciosa: análisis crítico de la bacteriología en Chile: el desafío de los hemocultivos negativos / Microbiology in infectious endocarditis: critical analysis of bacteriology in Chile: the challenge of the negative hemocultures

El diagnóstico etiológico de la EI (Endocarditis Infecciosa) se realiza fundamentalmente con el hemocultivo, el cual permite conocer el agente etiológico y su patrón de susceptibilidad para una adecuada antibioterapia. Esta técnica tradicionalmente manual, se automatizó en la década de los ochenta, logrando ampliar el espectro de agentes aislados, acortar los tiempos de detección y disminuir las tasas de contaminación. Desafortunadamente el acceso a esta tecnología no es uniforme en nuestro país lo que genera gran variabilidad en el rendimiento de los hemocultivos. Las EI con hemocultivos negativos representan un gran desafío clínico y microbiológico: el uso de antimicrobianos constituye la primera causa de hemocultivos negativos, sin embargo existen microorganismos fastidiosos o de nulo crecimiento que deben sospecharse en estos casos y con una buena comunicación con el laboratorio, evaluar el empleo de otras herramientas diagnósticas, como serología y PCR del hemocultivo y/o de vegetaciones en busca de ADN bacteriano, tecnología que ya se está evaluando en nuestro país. Por otro lado, el estudio microbiológico e histopatológico de válvulas removidas por EI debe ser obligatorio y constituye también un aporte, con resultados positivos aun bajo antibioterapia, dadas las dificultades para erradicar un microorganismo a ese nivel. Mejorar el diagnóstico etiológico de EI en Chile requiere educación, fundamentalmente para disminuir el empleo indiscriminado de antimicrobianos y cumplir con las normas de toma de muestras de hemocultivos. Además, implementar sistemas automatizados en todo el país constituiría un enorme avance, con beneficios innegables en el diagnóstico microbiológico.

Comparative study between culture media employed in sterility test.

The sterility test aims at the contact of a product with a culture medium, as a way of detecting the possible presence of viable microorganisms in products which have been submitted to a sterilization process and/or to aseptic processing. Since the official introduction of the methodology, in 1932, several culture media have been proposed and adopted, in a constant attempt to offer conditions which support the growth of as many contaminants as possible. This work aimed at a comparative evaluation of the efficiency of microbial contaminants detection in the different types of culture media employed in sterility tests. The study led to the conclusion that the culture media recommended by the pharmacopoeia compendia, soybean casein digest and fluid thioglycollate, present the best results in microorganisms detection. Besides, the microbial strains, as well as microbial suspension density, recommended by the main pharmacopoeias to verify culture media growth promoting capacity, have also proved suitable for use.

A prospective, randomized comparison of two commercial media for ICSI and embryo culture.

PURPOSE: The aim of this prospective, randomized study was to compare the results obtained in ICSI with two culture media, P-1 (Irvine Scientific) and IVF-50 (Scandinavian IVF Science). METHODS: A total of 182 patients undergoing ICSI treatment were randomly included in this study and divided in two groups: Group I: P-1 medium (n = 91) or Group II: IVF-50 medium (n = 91). All the embryos were transferred on the second day. RESULTS: Patient age did not differ (p = .29) between Group I (34.8 +/- 4.8) and Group II (34.0 +/- 4.5). The number of oocytes retrieved from Group I (10.6 +/- 6.7) was also similar (p = .49) to that retrieved from Group II (11.1 +/- 6.4). In addition, there was no difference (p = .25) in the number of oocytes retrieved at metaphase II between Group I (7.9 +/- 4.6) and Group II (8.7 +/- 4.6). Normal fertilization rates, abnormal fertilization rates, and cleavage rates were similar (p = .62, p = .48, and p = .9, respectively) between Group I (68.4 +/- 23.3%, 6.7 +/- 10.3%, and 98.7 +/- 4.6%) and Group II (65.3 +/- 26.2%, 9.0 +/- 13.8%, and 98.9 +/- 3.9%, respectively). The embryo score was also similar (p = .62) for both groups (Group I: 31.9 +/- 14.0 and Group II: 33.4 +/- 15.8). There was no difference in the number of embryos transferred (p = .69) between Group I (2.8 +/- 1.0) and Group II (2.8 +/- 1.1). In addition, pregnancy rates/puncture, pregnancy rates/transfer, implantation rates, and abortion rates were also similar for Group I (36.2%, 37.0%, 17.4%, and 12.1%, respectively) and Group II (31.8%, 33.7%, 15.8%, and 10.3%, respectively) (p = .64, p = .75, p = .72, and p = 1.0, respectively). CONCLUSIONS: There were no differences in the results obtained with culture media P-1 (Irvine Scientific) and IVF-50 (Scandinavian IVF Science) for ICSI and embryo culture.

Comparison of two selective media for the isolation of Campylobacter species from a pediatric population in Mexico.

Two selective media for the isolation of Campylobacter species, a blood containing medium (CampyBAP) and blood-free, charcoal based formulation (CCDA) were compared for the ability to isolate Campylobacter species during a 1-year period. Of the 1,132 stool samples cultured during the study, 42 Campylobacter species were recovered using both media (3.7% yield). CCDA was better than CampyBAP for isolating C. jejuni subsp jejuni (18/20 vs 8/20, P = 0.002) and for all isolates, CCDA was superior over CampyBAP (39/42 vs 13/42, P < 0.0001). Overall, CCDA is a superior medium compared with CampyBAP for isolating Campylobacter species in our study population.

Métodos de conservación de cultivos bacterianos / Bacterial culture preservation methods

Se dispone de una amplia variedad de técnicas para la preservación de cultivos bacteriano. Sin embargo puede resultar dificultoso elegir el método apropiado para la preservación de una determinada cepa, que no sólo asegure la viabilidad sino que también preserve el genotipo y en consecuencia, las características particulares de la misma. Este trabajo provee un compendio de los aspectos más importantes de los métodos disponibles, con referencias a investigaciones y aplicaciones recientes (AU)

Métodos de conservación de cultivos bacterianos / Bacterial culture preservation methods

Se dispone de una amplia variedad de técnicas para la preservación de cultivos bacteriano. Sin embargo puede resultar dificultoso elegir el método apropiado para la preservación de una determinada cepa, que no sólo asegure la viabilidad sino que también preserve el genotipo y en consecuencia, las características particulares de la misma. Este trabajo provee un compendio de los aspectos más importantes de los métodos disponibles, con referencias a investigaciones y aplicaciones recientes