Practice of standardization of CLSI M45 A3 antimicrobial susceptibility testing of Infrequently Isolated or Fastidious Bacteria strains isolated from blood specimens in Guangdong Province 2017-2021.

The concentration of antimicrobial agents in environments like water and food has increased rapidly, which led to a rapid increase in antimicrobial resistance levels in the environment. Monitoring of bacterial resistance levels is considered as a necessary means to control the bacterial resistance. Reference standards are critical for antimicrobial susceptibility testing. CLSI M45 A3 standard defines pathogenic microorganisms that cause infections less frequently than those covered by CLSI M02, M07, and M100 as Infrequently Isolated or Fastidious Bacteria and specifies antimicrobial susceptibility testing methods. Our study investigated the epidemiology and antimicrobial susceptibility testing data of Infrequently Isolated or Fastidious Bacteria strains isolated from blood specimens in 70 hospitals in Guangdong Province between 2017 and 2021. We defined testing methods other than those specified in CLSI M45 A3 as "Non-Standardized." The proportion of standardized antimicrobial susceptibility testing for penicillin increased significantly (Corynebacterium spp. 17.4% vs. 50.0% p < 0.05; Micrococcus spp. 50.0% vs. 77.8% p < 0.05; Abiotrophia spp. and Granulicatella spp. 21.4% vs. 90.9% p < 0.001), while for cefotaxime (Corynebacterium spp. 0.0% vs. 45.2% p < 0.05; Abiotrophia spp. and Granulicatella spp. 0.0% vs. 14.3% p = 0.515) and vancomycin increased finitely. Non-standardized methods were used for all other antimicrobials. Due to limitations in the economic and medical environment, some clinical laboratories are unable to fully comply with CLSI M45 A3 standard. We recommend that CLSI should add breakpoints for disk diffusion method to improve the standardization of antimicrobial susceptibility testing.

The performance of a Fully Automated Urine Particle Analyzer, Sysmex UF-5000, in detecting fastidious bacteria in urine samples.

Several types of fastidious bacteria can cause tract infections. We evaluated the performance of counting fastidious bacteria using a Fully Automated Urine Particle Analyzer UF-5000. The results showed that UF-5000 counts fastidious bacteria in urine without the need for culture using measurement principles based on flow cytometry.

Buffer-free CAS assay using a diluted growth medium efficiently detects siderophore production and microbial growth.

Siderophores are iron chelators and low-molecular-weight compounds secreted by various microorganisms under low-iron conditions. Many microorganisms produce siderophores in the natural environment as iron is an essential element for many of them. CAS assays are widely used to detect siderophores in cultures of various microorganisms; however, it is necessary to improve their sensitivity for the efficient application to fastidious microorganisms. We developed a simple, high-throughput CAS assay employing a buffer-free CAS reagent and diluted growth medium (10% dR2A) in a 96-well microplate. Using a diluted growth medium in agar plates suitable for iron-restricted conditions supported siderophore production by microorganisms from activated sludge. A buffer-free CAS reagent combined with a diluted growth medium revealed that these microorganisms tended to produce more siderophores or iron chelators than microorganisms under iron-rich conditions. Moreover, this buffer-free CAS assay easily and efficiently detected not only siderophore production but also the growth of fastidious microorganisms.

Granulicatella adiacens Endocarditis of a Bioprosthetic Aortic Valve.

Infective endocarditis (IE) is relatively uncommon; however, when it is diagnosed, it is usually among those with known cardiac valvular abnormalities. The most common pathogens that cause endocarditis are streptococci (mainly viridans), enterococci, and other streptococci species. An extremely rare pathogen that could cause IE is Granulicatella. This gram-positive coccus classically inhabits human mucosal surfaces and only rarely causes disease. We present an incredibly rare case of a 74-year-old female with a bioprosthetic aortic valve replacement, who presented with headache and weakness and was subsequently found to have recurrent Granulicatella adiacens infective endocarditis.

Bartholin's gland cyst caused by Sneathia amnii: a case report.

BACKGROUND: Sneathia amnii is a conditional pathogen of the female genital tract that is involved in bacterial vaginosis and poor reproductive and perinatal outcomes. Few studies have reported subcutaneous cysts following invasive infection caused by S amnii. CASE PRESENTATION: Here we report the case of a 27-year-old woman who presented with Bartholin's gland cyst due to S amnii infection, and was successfully treated with surgical neostomy and antibiotic agents. The isolate was gram-negative, bacillary, anaerobic, and was identified by polymerase chain reaction (PCR) amplification of the 16 S rRNA. CONCLUSIONS: S amni is an important but underappreciated pathogen that needs further investigation. This report describes the microbial and pathogenic characteristics of S amnii and is expected to provide a valuable reference in obstetric and gynecologic clinical practice.

Prediction of presence of fastidious bacteria by the Fully Automated Urine Particle Analyzer UF-1000i in the case of ineffective antimicrobial therapy for urinary tract infection.

INTRODUCTION: Recent studies have reported associations between fastidious bacteria that are difficult to grow and isolate in conventional urine culture conditions and urinary tract infections (UTIs). Because the Fully Automated Urine Particle Analyzer UF-1000i (hereinafter referred to as "UF-1000i") detects fastidious bacteria without being affected by culture conditions, owing to its flow cytometry-based principle, we evaluated the robustness of UF-1000i detection using clinical urine samples from patients with UTIs following ineffective antimicrobial therapy. METHODS: A total of 150 patients diagnosed with UTIs were enrolled, and their laboratory findings were analyzed, focusing on the discrepancy in bacterial numbers between UF-1000i and conventional culture at each antimicrobial therapy effectiveness classification. In addition, gene identification was conducted by molecular analysis using 16S ribosomal RNA gene sequencing and next-generation sequencing (NGS) to elucidate the reason for the presence of fastidious bacteria in these samples. RESULTS: The ineffective therapy cases showed more than 100-fold discrepancy in bacterial counts, with a higher proportion (30.8%) than effective therapy cases without secondary administration (5.7%) between the bacterial counts in UF-1000i and conventional culture methods. The presence rates of fastidious bacteria were 100% and 66.7% in discrepant cases of ineffective and effective without secondary administrations, respectively. CONCLUSION: This study suggests that discrepancies in bacterial numbers between the conventional culture method and UF-1000i measurement at the primary visit can predict the presence of fastidious bacteria, especially in cases of ineffective antimicrobial therapy.

Development of a long-read next generation sequencing workflow for improved characterization of fastidious respiratory mycoplasmas.

Mycoplasma cynos and Mycoplasma felis are often associated with canine and feline infectious respiratory disease in dogs and cats, respectively. Mycoplasmas have a reduced genome and dearth of many biosynthetic pathways, making them dependent on rich medium for growth. Due to this fastidious nature, mycoplasmas have been historically underdiagnosed. The aim of this study was to develop a cost-effective and accurate sequencing workflow for genotypic characterization of clinical isolates of M. cynos and M. felis using a rapid long-read sequencing platform. We explored the following critical aspects of bacterial whole genome sequencing, including: (i) five solid and liquid-based culture approaches based on a specialized media formulation for Mycoplasma culture, (ii) three DNA extraction methods modified for long-read sequencing purposes, and (iii) two de novo assembly platforms, Flye and Canu, as key components of a bioinformatics pipeline. DNA extraction method 1, a solid-phase and column-based kit with enzymatic lysis, provided the best DNA quality and concentration followed by high coverage and sequencing contiguity. This was obtained with a culture volume of 45 ml in modified Hayflick's broth incubated for 48 h. DNA extracted directly from colonies on agar or from small broth volumes (6 ml) did not meet the criteria required for long-read sequencing. Overall, Flye generated more contiguous assemblies than the Canu assembler and was more time efficient. This 4-5 day sample-to-sequence workflow provides the scientific and clinical communities with a more comprehensive tool than laborious conventional methods for complete genomic characterization of M. cynos and M. felis clinical isolates.

Identification and Characterization of Potato Zebra Chip Resistance Among Wild Solanum Species.

Potato zebra chip (ZC) disease, associated with the uncultured phloem-limited bacterium, Candidatus Liberibacter solanacearum (CLso), is transmitted by the potato psyllid Bactericera cockerelli. Potato ZC disease poses a significant threat to potato production worldwide. Current management practices mainly rely on the control of the psyllid to limit the spread of CLso. The present study investigated new sources of ZC resistance among wild Solanum species. A taxonomically diverse collection of tuber-bearing Solanum species was screened; one ZC-resistant accession and three ZC-tolerant accessions were identified among the 52 screened accessions. Further characterization of the resistant accession showed that the resistance was primarily associated with antibiosis effects due to differences in leaf trichome density and morphology of the wild accession, which could limit the psyllid feeding and oviposition. This germplasm offers a good resource for further understanding ZC and psyllid resistance mechanisms, contributing to potato breeding efforts to develop ZC resistance cultivars. Alternatively, it could be used as a potential trap crop to manage psyllid and control ZC disease.

Engineering a new vaccine platform for heterologous antigen delivery in live-attenuated Mycobacterium tuberculosis.

Live vaccines are attractive vehicles for antigen delivery as a strategy to immunize against heterologous pathogens. The live vaccine MTBVAC is based on rational attenuation of Mycobacterium tuberculosis with the objective of improving BCG protection against pulmonary tuberculosis. However, the development of recombinant mycobacteria as antigen-presenting microorganisms has been hindered due to their fastidious genetic manipulation. In this study, we used MTBVAC as a genetic platform to deliver diphtheria, tetanus, or pertussis toxoids, which are the immunogenic constituents of the DTP vaccine. When using nonoptimal genetic conditions, the expression of these immunogens was barely detectable. Accordingly, we pursued a rational, step-by-step optimization of the genetic components to achieve the expression and secretion of these toxoids. We explored variants of the L5 mycobacteriophage promoter to ensure balanced antigen expression and plasmid stability. Optimal signal sequences were identified by comparative proteomics of MTBVAC and its parental strain. It was determined that proteins secreted by the Twin Arginine Translocation pathway displayed higher secretion in MTBVAC, and the Ag85A secretion sequence was selected as the best candidate. Because the coding regions of diphtheria, tetanus, and pertussis toxoids significantly differ in G + C content relative to mycobacterial genes, their codon usage was optimized. We also placed a 3xFLAG epitope in frame with the C-terminus of these toxoids to facilitate protein detection. Altogether, these optimizations resulted in the secretion of DTP antigens by MTBVAC, as demonstrated by western blot and MRM-MS. Finally, we examined specific antibody responses in mice vaccinated with recombinant MTBVAC expressing DTP antigens.

Potato Zebra Chip: An Overview of the Disease, Control Strategies, and Prospects.

Potato (Solanum tuberosum L.) is an important food crop worldwide. As the demand for fresh and processed potato products is increasing globally, there is a need to manage and control devastating diseases such as zebra chip (ZC). ZC disease causes major yield losses in many potato-growing regions and is associated with the fastidious, phloem-limited bacterium Candidatus Liberibacter solanacearum (CLso) that is vectored by the potato-tomato psyllid (Bactericera cockerelli Sulc). Current management measures for ZC disease mainly focus on chemical control and integrated pest management strategies of the psyllid vector to limit the spread of CLso, however, they add to the costs of potato production. Identification and deployment of CLso and/or the psyllid resistant cultivars, in combination with integrated pest management, may provide a sustainable long-term strategy to control ZC. In this review, we provide a brief overview of the ZC disease, epidemiology, current management strategies, and potential new approaches to manage ZC disease in the future.

A novel engineered label-free Zn-based MOF/CMC/AuNPs electrochemical genosensor for highly sensitive determination of Haemophilus Influenzae in human plasma samples.

An innovative label-free DNA genosensing assay based on a direct hybridization followed by DPASV in the presence of [Fe(CN)6]4-/3- was developed for recognizing the H. influenza genome in human plasma samples. To attain this objective, Zn-based MOF was synthesized and combined with carboxymethyl cellulose (CMC), which were immobilized on the surface of Au electrode and AuNPs were immobilized on the Zn-based MOF/CMC/Au-modified electrode surface. The genosensing bio-assay provides high specificity, sensitivity, and good performance for the determination of L-fuculokinase gene from the Haemophilus influenza genome. Various characterization techniques were applied including Fe-SEM, EDS, FT-IR, and XRD for investigation of morphological features and particle size. Under optimal conditions LOD and LOQ were 1.48 fM and 3.23 fM, respectively. Moreover, a wide linear range was obtained ranging from 0.1 pM-10 nM for t-DNA. The recoveries and RSDs were 98.4-103% and 2.2-3.2, respectively. The fabricated biosensing assay presented high selective ability of one, two, and three-base mismatched sequences. In addition, negative control of the genosensing assay for investigation of the selectivity was performed by the t-DNAs of Salmonella typhimurium and Shigella flexneri bacteria. Likewise, reproducibility and repeatability of the related bio-assay were investigated. It is to be noted that the organized genosensing bio-assay can be straightforwardly reused and regenerated to assess the hybridization process.

Proof of Concept of Culturomics Use of Time of Care.

Culturomics, a high throughput culture method with rapid identification of the colonies by Matrix Assisted Laser Desorption Ionization/Time Of Flight Mass Spectrometry (MALDI-TOF MS), has demonstrated its contribution to the exploration of the gut microbiota over the past 10 years. However, the cost, work time and workload, considerably limit its use on a large scale or emergency context. Here, by testing two different stool samples, including a stool sample from a patient requiring rapid immunotherapy treatment, we tested a new fast culturomic protocol using two pre-incubation media, blood culture bottle and YCFA modified medium. Both media were supplemented with 2 ml of rumen fluid filtered at 0.2 µm and 2 ml of defibrinated and sterile sheep blood. Unlike the standard culturomics, subculturing of blood culture bottle were performed at reduced incubation time (3 h, 6 h, 9 h, 24 h) and at a longer incubation time (3 days, 7 days, and 10 days) at 37°C. By testing 5,200 colonies per MALDI-TOF MS and obtaining a comparable number of cultured bacterial species (131 to 143) in a stool sample, this new protocol reduced the number of colonies tested by 57%, working time by 78.6% and cost by 72.2%. In addition, we highlighted that the proportion of strict anaerobic species has increased by 24%, known to be the preferential targets for biotherapy, including Faecalibacterium prausnitzii, Akkermansia muciniphila, Christensenella minuta, and Phascolarctobacterium faecium. Finally, this work showed that some bacterial species grew earlier but disappeared with prolonged incubation times.

Parallel detection of lactobacillus and bacterial vaginosis-associated bacterial DNA in the chorioamnion and vagina of pregnant women at term.

BACKGROUND: The majority of early preterm births are associated with intrauterine infections, which are thought to occur when microbes traffic into the uterus from the lower genital tract and seed the placenta. Bacterial vaginosis (BV) is associated with heterogeneous bacterial communities in the vagina and is linked to preterm birth. The extent to which trafficking into the uterus of normal and BV-associated vaginal bacteria occurs is unknown. The study objective was to characterize in parallel the distribution and quantities of bacteria in the vagina, uterus, and placental compartments. METHODS: Pregnant women at term (≥37 weeks) presenting for delivery were recruited prospectively. Swabs were collected in parallel from the vagina, chorioamnion. Choriodecidual swabs were collected if a cesarean section was performed. Samples were analyzed by culture, broad-range 16S rRNA gene PCR, and bacterial species-specific quantitative PCR (qPCR) for DNA from Lactobacillus and a panel of BV-associated bacteria. Results were correlated with placental histopathology. RESULTS: Of the 23 women enrolled, 15 were delivered by cesarean section (N = 10 without labor; N = 5 in labor) and eight were delivered vaginally. BV was diagnosed in two women not in labor. Placental histopathology identified chorioamnionitis or funisitis in six cases [1/10 (10%) not in labor; 5/13 (38%) in labor]. Among non-laboring women, broad-range 16S qPCR detected bacteria in the chorioamnion and the choriodecidua (4/10; 40%). Among laboring women, Lactobacillus species were frequently detected in the chorioamnion by qPCR (4/13; 31%). In one case, mild chorioamnionitis was associated with qPCR detection of similar microbes in the chorioamnion and vagina (e.g. Leptotrichia/Sneathia, Megasphaera), along a quantitative gradient. CONCLUSIONS: Microbial trafficking of lactobacilli and fastidious bacteria into the chorioamniotic membranes and choriodecidua occurs at term in normal pregnancies. In one case, we demonstrated a quantitative gradient between multiple bacterial species in the lower genital tract and placenta. Not all bacterial colonization is associated with placental inflammation and clinical sequelae. Further studies of the role of placental colonization with Lactobacillus in normal pregnancy and fastidious bacteria in chorioamnionitis may improve prevention and treatment approaches for preterm labor.

Bioassays: The best alternative for conventional methods in detection of Legionella pneumophila.

Fastidious bacteria are group of bacteria that not only grow slowly but also have complex nutritional needs. In this review, recent progress made on development of biosensing strategies towards quantification of Legionella pneumophila as fastidious bacteria in microbiology was investigated. In coincidence with medical bacteriology, it is the most widely used bio-monitoring, biosensors based on DNA and antibody. Also, all of legionella pneumophila genosensors and immunosensors that developed in recent years were collected analyzed. This review is meant to provide an overview of the various types of bioassays have been developed for determination of Legionella Legionella, along with significant advances over the last several years in related technologies. In addition, this review described: i) Most frequently applied principles in bioassay/biosensing of Legionellaii) The aspects of fabrication in the perspective of bioassay/biosensing applications iii) The potential of various electrochemical and optical bioassay/biosensing for the determination of Legionella and the circumvention of the most serious problem in immunosensing/immunoassay was discussed. iv) Some of bioassay/biosensing has been discussed with and without labels. v) We also summarize the latest developments in the applications of bioassay/biosensing methods for detection of Legionella. vi) The development trends of optical and electrochemical based bioassay/biosensing are also introduced.

Potato purple top disease associated with the novel subgroup 16SrII-X phytoplasma.

Potato (Solanum tuberosum) is a very economically important perennial tuberous crop in Saudi Arabia. Potato plants displaying symptoms associated with potato purple top disease, such as aerial tubers and purple and small leaves, were observed in Al-Bukairiyah, Fowlq and Buraydah, Al-Tarafiyah, Qassim governorate, Saudi Arabia. In this study, we examined samples taken from 12 symptomatic potato plants and confirmed the presence of phytoplasma DNA. Analysis of the 16S rRNA-encoding sequences revealed that the symptomatic plants were infected with phytoplasma belonging to the peanut witches'-broom group (16SrII). Sequencing of the 16S rRNA- encoding gene, computer-simulated RFLP analysis and phylogenetic analysis revealed the presence of a novel representative of the 16SrII-X subgroup. The present study identified potato plants as a novel host for novel phytoplasma strains belonging to the pigeon pea witches'-broom group in Saudi Arabia.

Delineation of a novel subgroup 16SrXIII-J phytoplasma, a 'Candidatus Phytoplasma hispanicum'-related strain, based on computer-simulated RFLP and phylogenetic analysis.

Symptoms of fruit phyllody and slow growth, which are suggestive of phytoplasma infection, were observed in strawberry plants cultivated in commercial fields. In order to provide evidence of association of phytoplasma with affected plants, assays for detecting and identifying were performed through computer-simulated restriction fragment length polymorphism (RFLP) and phylogenetic analysis. Total DNA was extracted from symptomatic and asymptomatic samples and used as template in nested PCR primed by the primers P1/Tint followed by R16F2n/16R2. Amplified DNA fragments of 1.2 kb from the 16S rRNA gene revealed the presence of phytoplasma in all symptomatic samples. Molecular detection was confirmed by electron transmission microscopy, which evidenced pleomorphic bodies in the phloem vessels. Nucleotide sequence representative of the strawberry phytoplasma shared 97.2 to 99 % similarity with phytoplasmas currently classified as members of the distinct subgroups within the 16SrXIII group. Similarity coefficient (F) values ranged from 0.70 to 0.92, indicating that strawberry phytoplasma delineates a new strain in addition to 'Candidatus Phytoplasma hispanicum'-related strains. The evolutionary tree displayed that this strain emerges as a new branch in relation to those previously described. The novel strain, designated SFP (strawberry fruit phyllody) phytoplasma represents the new 16SrXIII-J subgroup and its sequence, denominated SFP-Br02, was deposited in the GenBank database (EU719108). These findings contribute for the knowledge of the genetic diversity existing among members of the group 16SrXIII and establishes strawberry as an additional host of representatives of this group in Brazil.

Genome Analysis of Haplotype D of Candidatus Liberibacter Solanacearum.

Candidatus Liberibacter solanacearum (Lso) haplotype D (LsoD) is a suspected bacterial pathogen, spread by the phloem-feeding psyllid Bactericera trigonica Hodkinson and found to infect carrot plants throughout the Mediterranean. Haplotype D is one of six haplotypes of Lso that each have specific and overlapping host preferences, disease symptoms, and psyllid vectors. Genotyping of rRNA genes has allowed for tracking the haplotype diversity of Lso and genome sequencing of several haplotypes has been performed to advance a comprehensive understanding of Lso diseases and of the phylogenetic relationships among the haplotypes. To further pursue that aim we have sequenced the genome of LsoD from its psyllid vector and report here its draft genome. Genome-based single nucleotide polymorphism analysis indicates LsoD is most closely related to the A haplotype. Genomic features and the metabolic potential of LsoD are assessed in relation to Lso haplotypes A, B, and C, as well as the facultative strain Liberibacter crescens. We identify genes unique to haplotype D as well as putative secreted effectors that may play a role in disease characteristics specific to this haplotype of Lso.

Possible Role of Rickettsia felis in Acute Febrile Illness among Children in Gabon.

Rickettsia felis has been reported to be a cause of fever in sub-Saharan Africa, but this association has been poorly evaluated in Gabon. We assessed the prevalence of this bacterium among children <15 years of age in 4 areas of Gabon; the locations were in urban, semiurban, and rural areas. DNA samples from 410 febrile children and 60 afebrile children were analyzed by quantitative PCR. Overall, the prevalence of R. felis among febrile and afebrile children was 10.2% (42/410 children) and 3.3% (2/60 children), respectively. Prevalence differed among febrile children living in areas that are urban (Franceville, 1.3% [1/77]), semiurban (Koulamoutou, 2.1% [3/141]), and rural (Lastourville, 11.2% [15/134]; Fougamou, 39.7% [23/58]). Furthermore, in a rural area (Fougamou), R. felis was significantly more prevalent in febrile (39.7% [23/58]) than afebrile children (5.0% [1/20]). Additional studies are needed to better understand the pathogenic role of R. felis in this part of the world.

A simple and novel method for retrieval of Pasteurellaceae from swab samples collected in the field.

Traditionally it has been difficult or impossible to collect and preserve bacterial samples of especially fastidious bacteria in mixed primary cultures, unless the samples could be transported to a laboratory within approximately 24 h. Therefore, a simple novel method for preserving swab samples until bacterial isolation can be completed in the laboratory was developed and evaluated. Pasteurellaceae bacteria were used as a representative for fastidious bacteria. A 7.5% glucose serum medium was used as freeze medium. Swab samples were soaked in the medium a maximum of 2 h after collection and stored at -20°C. As a control study, 15 samples were collected from the oral cavity of a captive brown bear. One was immediately plated, while the remaining 12 swabs were stored at -20°C for 7 days and multiples of 30 days up to 330 days prior to plating. Two samples were stored without the medium for 7 and 30 days prior to plating. From a field setting in Greenland, eight polar bear samples were collected and subsequently stored for 240 to 259 days at -20°C before incubation. Pasteurellaceae bacteria were isolated and genotyped from all samples stored in the freeze medium, indicating that the medium enabled the bacteria to survive for at least 330 days at -20°C. The 100% recovery of target organisms in the polar bear samples even following lengthy storage and transport demonstrates that the method is very useful under remote field conditions.

A Gardnerella vaginalis e as infecções do trato urinário / The Gardnerella vaginalis and the urinary tract infections

As infecções do trato urinário (ITUs) estão entre as mais frequentes nos seres humanos. São causadas por grande variedade de uropatógenos habituais, porém podem ser provocadas por alguns micro-organismos fastidiosos, como a Gardnerella vaginalis, que é uma bactéria anaeróbia facultativa, observada sob a forma de cocobacilos Gram-variáveis. Ela habita a mucosa vaginal e eventualmente pode ocasionar ITUs. O isolamento pode ser realizado em amostras de urina utilizando o ágar CNA (colistina e ácido nalidíxico), com incubação de 48 a 72 horas em atmosfera rica em CO2. O exame de Gram de urina não centrifugada pode auxiliar o microbiologista na identificação das amostras nas quais uma bactéria fastidiosa seja o agente causal, já que a visualização de inúmeras células epiteliais, a ausência de leucócitos e a presença de mais de um tipo morfológico sugerem contaminação da amostra. Como estudos comprovam a incidência de G. vaginalis entre os agentes causadores de ITUs, o isolamento em uroculturas não deve ser desprezado. A interpretação clínica do crescimento da G. vaginalis é de difícil avaliação, sendo imprescindível a troca de informações entre o laboratório de microbiologia clínica e a equipe médica, investigando a presença de sinais e sintomas que possam estar associados à ITU.

Urinary tract infections are among the most recurrent in human beings. They are caused by a wide variety of usual uropathogens, although they may be caused by some fastidious micro-organisms, such as Gardnerella vaginalis. It is a facultative anaerobe, found in the form of Gram-variable coccobacilli. It inhabits the vaginal mucosa and occasionally may cause urinary tract infections. The isolation may be performed on urine samples using CNA agar, incubated for 48-72 hours in atmosphere rich in CO2. The Gram examination of non-centrifuged urine may aid the microbiologist in identifying samples in which a fastidious bacterium is the causative agent, since the visualization of numerous epithelial cells, the absence of leukocytes and the presence of more than one morphological type suggest sample contamination. As studies show the Gardnerella vaginalis incidence among the causative agents of urinary tract infections, the isolation in urine cultures can not be overlooked. The clinical interpretation of the Gardnerella vaginalis growth is difficult to assess, thus being essential the information exchange between the clinical microbiology laboratory and medical staff in order to investigate the presence of signs and symptoms that may be associated with urinary tract infections.