Corynebacterium seminale sp. nov., a new species associated with genital infections in male patients

Prevalence and antimicrobial susceptibility profile of Corynebacterium glucuronolyticum in genitourinary tract samples

INTRODUCTION

Corynebacterium glucuronolyticum (C. glucuronolyticum) is a species recently recognized as a potential pathogen of the male genitourinary tract. The objective is to determine the prevalence of C. glucuronolyticum in genitourinary tract samples as well as their antimicrobial susceptibility profile.

METHODS

A prospective study was conducted from 1st of November 2021 to the 30th of November 2022, for all genitourinary tract samples collected from male patients with suspicion of balanitis, prostatitis and urethritis. Antimicrobial susceptibility testing was performed in all C. glucuronolyticum isolates.

RESULTS

A total of 73 C. glucuronolyticum isolates from 693 clinical specimens were obtained. This represents an overall C. glucuronolyticum prevalence of 10.5%. All strains were susceptible to vancomycin, linezolid and rifampicin, whereas 94%, 68% and 65% were resistant to clindamycin, tetracycline and ciprofloxacin, respectively.

CONCLUSION

Clinical microbiology laboratories should perform antimicrobial susceptibility testing against C. glucuronolyticum due to the significant rate of resistance to ciprofloxacin and tetracycline.

Microbiota composition and diversity of multiple body sites vary according to reproductive performance in a seabird

The microbiota is suggested to be a fundamental contributor to host reproduction and survival, but associations between microbiota and fitness are rare, especially for wild animals. Here, we tested the association between microbiota and two proxies of breeding performance in multiple body sites of the black-legged kittiwake, a seabird species. First we found that, in females, nonbreeders (i.e., birds that did not lay eggs) hosted different microbiota composition to that of breeders in neck and flank feathers, in the choanae, in the outer-bill and in the cloacae, but not in preen feathers and tracheae. These differences in microbiota might reflect variations in age or individual quality between breeders and nonbreeders. Second, we found that better female breeders (i.e., with higher body condition, earlier laying date, heavier eggs, larger clutch, and higher hatching success) had lower abundance of several Corynebacteriaceae in cloaca than poorer female breeders, suggesting that these bacteria might be pathogenic. Third, in females, better breeders had different microbiota composition and lower microbiota diversity in feathers, especially in preen feathers. They had also reduced dispersion in microbiota composition across body sites. These results might suggest that good breeding females are able to control their feather microbiota-potentially through preen secretions-more tightly than poor breeding females. We did not find strong evidence for an association between reproductive outcome and microbiota in males. Our results are consistent with the hypothesis that natural variation in the microbiota is associated with differences in host fitness in wild animals, but the causal relationships remain to be investigated.

Effect of indoor environmental exposure on seminal microbiota and its application in body fluid identification

Semen is a common body fluid type in forensic sexual assault cases. It is of great significance to effectively identify semen for restoring the crime scene and determining the nature of the case. Nowadays, microbiome-based method shows as a promising tool for forensic body fluid identification. To explore the environmental impact on microbial community of semen and its traceability, 16S rDNA high-throughput sequencing was conducted to ten paired semen samples. Affected by exposure, the diversity of microbial community decreased generally as the genus Staphylococcus exhibited a relatively significant increase. However, the genus Staphylococcus, Corynebacterium, Corynebacterium_1 were observed in almost all 20 samples. Community barplot analysis and heatmap analysis showed composition of the predominant microbe in semen at the phyla and genus level maintained basically, so that it could distinguish from vaginal fluid and saliva regardless of environmental exposure. Based on these results, we believe the application of single microbial marker may limit in semen identification, but the method depending on microbial community might be useful for distinguishing semen even under indoor exposure.

Ureaplasma diversum protein interaction networks: evidence of horizontal gene transfer and evolution of reduced genomes among Mollicutes

Ureaplasma diversum is a member of the Mollicutes class responsible for urogenital tract infection in cattle and small ruminants. Studies indicate that the process of horizontal gene transfer, the exchange of genetic material among different species, has a crucial role in mollicute evolution, affecting the group's characteristic genomic reduction process and simplification of metabolic pathways. Using bioinformatics tools and the STRING database of known and predicted protein interactions, we constructed the protein-protein interaction network of U. diversum and compared it with the networks of other members of the Mollicutes class. We also investigated horizontal gene transfer events in subnetworks of interest involved in purine and pyrimidine metabolism and urease function, chosen because of their intrinsic importance for host colonization and virulence. We identified horizontal gene transfer events among Mollicutes and from Ureaplasma to Staphylococcus aureus and Corynebacterium, bacterial groups that colonize the urogenital niche. The overall tendency of genome reduction and simplification in the Mollicutes is echoed in their protein interaction networks, which tend to be more generalized and less selective. Our data suggest that the process was permitted (or enabled) by an increase in host dependence and the available gene repertoire in the urogenital tract shared via horizontal gene transfer.

A microbial game of whack-a-mole: clinical case series of the urethral uncloaking phenomenon caused by Corynebacterium glucuronolyticum in men treated for Chlamydia trachomatis urethritis

Corynebacterium glucuronolyticum is a rare and neglected, but increasingly recognized bacterial agent of infectious urethritis and other genitourinary syndromes in men. This is the first description of its proclivity to resurface as a cause of sustained urethritis in male patients previously treated for Chlamydia trachomatis, which represents a phenomenon that has to be differentiated from a simple post-treatment overgrowth of a colonizing agent.

Genome-Based Taxonomic Classification of the Phylum Actinobacteria

The application of phylogenetic taxonomic procedures led to improvements in the classification of bacteria assigned to the phylum Actinobacteria but even so there remains a need to further clarify relationships within a taxon that encompasses organisms of agricultural, biotechnological, clinical, and ecological importance. Classification of the morphologically diverse bacteria belonging to this large phylum based on a limited number of features has proved to be difficult, not least when taxonomic decisions rested heavily on interpretation of poorly resolved 16S rRNA gene trees. Here, draft genome sequences of a large collection of actinobacterial type strains were used to infer phylogenetic trees from genome-scale data using principles drawn from phylogenetic systematics. The majority of taxa were found to be monophyletic but several orders, families, and genera, as well as many species and a few subspecies were shown to be in need of revision leading to proposals for the recognition of 2 orders, 10 families, and 17 genera, as well as the transfer of over 100 species to other genera. In addition, emended descriptions are given for many species mainly involving the addition of data on genome size and DNA G+C content, the former can be considered to be a valuable taxonomic marker in actinobacterial systematics. Many of the incongruities detected when the results of the present study were compared with existing classifications had been recognized from 16S rRNA gene trees though whole-genome phylogenies proved to be much better resolved. The few significant incongruities found between 16S/23S rRNA and whole genome trees underline the pitfalls inherent in phylogenies based upon single gene sequences. Similarly good congruence was found between the discontinuous distribution of phenotypic properties and taxa delineated in the phylogenetic trees though diverse non-monophyletic taxa appeared to be based on the use of plesiomorphic character states as diagnostic features.

The impact of Corynebacterium glucuronolyticum on semen parameters: a prospective pre-post-treatment study

Corynebacterium glucuronolyticum (C. glucuronolyticum) is a rare isolate that is only recently being acknowledged as a potential urogenital pathogen. The bibliographical references on this bacterial species are scarce, and its influence on all semen parameters was hitherto unknown - therefore, the aim of this study was to evaluate its effects on a range of sperm quality parameters. A prospective approach to compare semen parameters before and after treatment was used in this study. C. glucuronolyticum in semen specimens was identified using analytical profile index biotyping system (API Coryne) and additionally confirmed by matrix-assisted laser desorption/ionization time-of-flight mass-spectrometry (MALDI-TOF MS), with the determination of antimicrobial susceptibility by Kirby-Bauer method. Semen analysis was performed according to the criteria from the World Health Organization (with the use of Tygerberg method of sperm morphology categorization). Very strict inclusion criteria for participants also included detailed medical history and urological evaluation. From a total of 2169 screened semen specimens, the inclusion rate for participants with C. glucuronolyticum that satisfied all the criteria was 1.01%. Antibiogram-guided treatment of the infection with ensuing microbiological clearance has shown that the resolution of the infection correlates with statistically significant improvement in the vitality of spermatozoa, but also with a lower number of neck and mid-piece defects. Parameters such as sperm count, motility and normal morphology were not affected. In addition, susceptibility testing revealed a trend towards ciprofloxacin resistance, which is something that should be considered when selecting an optimal treatment approach. Albeit it is rarely encountered as a monoisolate in significant quantities, C. glucuronolyticum may negatively influence certain sperm parameters; therefore, it has to be taken into account in the microbiological analysis of urogenital samples.

Seminal Corynebacterium strains in infertile men with and without leucocytospermia

This study aimed to identify seminal Corynebacterium strains in infertile men with and without leucocytospermia. Semen samples from 60 infertile men were allocated into two equal groups: semen samples with leucocytospermia and semen samples without leucocytospermia. Semen culture for Corynebacterium species was carried out on Columbia agar medium confirmed by Gram-stained film and biochemical tests followed by analytical profile index biotyping and antibiotic susceptibility. Bacterial isolates were detected in 20/60 semen cultures (33.3%) as Corynebacteria, Staphylococci, Alpha haemolytic streptococci and E. coli. In all, 12/60 (20%) had Corynebacterium positive semen culture, whereas C. seminal was the major isolated species followed by C. amycolatum, C. jekium and C. urealyticum. There was nonsignificant difference between patients with/without Corynebacterium positive culture regarding sperm concentration and normal sperm morphology; however, in positive cultures sperm motility was significantly lower compared with negative cultures. Antimicrobial sensitivity among Corynebacteria strains was highest for vancomycin, rifampicin then imipenem, ampicillin + sulbactam, ciprofloxacin. It is concluded that positive semen cultures for different Corynebacteria species were demonstrated in infertile men, whereas Corynebacterium seminale was the most common isolated species. Vancomycin, rifampicin then imipenem and ampicillin + sulbactam are recommended as sensitive antibiotics.

Corynebacterium glucuronolyticum causing genitourinary tract infection: Case report and review of the literature

Corynebacterium species are increasingly recognized as opportunistic pathogens. A growing number of taxonomic studies has yielded a description of numerous new Corynebacterium species, such as those related to the urogenital tract, with Corynebacterium glucuronolyticum found to be rarely involved in genitourinary tract infections, particularly in male individuals. In this report, we describe a urethritis case caused by C. glucuronolyticum in a 37-year-old, apparently healthy male, who complained mild pain in the lower abdomen, with several urinary symptoms. While urethral and semen specimens did not yield positive results for microbiological evaluation, cultures of urine samples revealed the monomicrobial growth on blood-containing media of tiny colonies after 24 h of incubation, clearly evident only after 48 h of incubation under CO2-enriched atmosphere. Colonies were identified as C. glucuronolyticum both by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) and 16S rRNA gene sequencing. Oral ciprofloxacin gradually led to clinical improvement and, finally, to a complete recovery, in accordance with microbiological findings. In spite of its infrequent detection, C. glucuronolyticum might be a potential urogenital pathogen in males more commonly that what believed, perhaps due to slow growth leading to underrecognition; we suggest therefore to consider the organism in the differential diagnostics of bacterial diseases of the urinary tract.

Complete Genome Sequence of Corynebacterium ureicelerivorans DSM 45051, a Lipophilic and Urea-Splitting Isolate from the Blood Culture of a Septicemia Patient

Corynebacterium ureicelerivorans is an opportunistic pathogen with a lipophilic lifestyle and an exceptionally high urease activity. The genome sequence of the type strain revealed that lipophilism is caused by the lack of a fatty acid synthase gene. The ureABCEFGD genes are similar to the urease gene region of Corynebacterium glucuronolyticum .

Coryneform bacteria in human semen: inter-assay variability in species composition detection and biofilm production ability

Background

Coryneform bacteria constitute an important segment of male urogenital microbiota. They have been generally considered as saprophytes, although some species have been associated with prostatitis as well. At the same time, biofilm infections have been suspected as a cause of prostatitis.

Objective

To identify a set of coryneform bacteria isolated from semen of either healthy men or prostatitis patients applying different methods to reveal inter-assay variability and to determine their ability of adhesion and biofilm production.

Design

Coryneform bacteria were identified by API Coryne 2.0 biochemical identification system and 16S rDNA sequencing using different primer sets. Quantitative assessment of biofilm production was performed using crystal violet binding assay method.

Results

The most common species were Corynebacterium seminale, C. minutissimum, and Dermabacter hominis. Altogether 14 species and related genera were found. We observed the best inter-assay agreement when identifying C. seminale. Biofilm was observed in 7 out of 24 strains. The biofilm-producing strains belonged to Arthrobacter cumminsii, Dermabacter hominis, C. minutissimum, and Actinomyces neuii. No differences were found between the strains originating from prostatitis patients and healthy men. Dermabacter hominis strains were more potent biofilm producers than C. seminale strains (p=0.048).

Conclusions

We can conclude that a wide variety of coryneform bacteria can be found from the male genital tract, although their exact identification is problematic due to insufficient representation in databases. Nearly one third of the strains are able to form biofilm that may give them an advantage for surviving several host- and treatment-related conditions.

Corynebacterium pyruviciproducens sp. nov., a pyruvic acid producer

A coryneform strain, 06-1773OT (=WAL 19168T), derived from a groin abscess sample was characterized using phenotypic and molecular taxonomic methods. Comparative analyses revealed more than 3 % divergence of the 16S rRNA gene sequence and about 10 % divergence of the partial rpoB gene sequence from the type strain of Corynebacterium glucuronolyticum. The strain could also be differentiated from C. glucuronolyticum by a set of phenotypic properties. A DNA–DNA relatedness study between strain WAL 19168T and C. glucuronolyticum CCUG 35055T showed a relatedness value of 13.3 % (13.7 % on repeat analysis). The genotypic and phenotypic data show that the strain merits classification within a novel species of Corynebacterium. We propose the name Corynebacterium pyruviciproducens sp. nov. for the novel species. The type strain is 06-1773OT (=WAL 19168T =CCUG 57046T =ATCC BAA-1742T).

Phenotypic differences between coryneform bacteria isolated from seminal fluid of healthy men and men with chronic prostatitis syndrome

We compared the potential phenotypic properties of coryneform bacteria associated with chronic prostatitis syndrome (CPS), such as secretory inhibitor of lysozyme (SIL) and secretory inhibitor of platelet microbicidal protein (SIPMP). A total of 110 clinical isolates of coryneform bacteria isolated from the seminal fluid of healthy men and men with CPS were tested. SIPMP production was tested by inhibiting platelet microbicidal protein (PMP) bioactivity against Bacillus subtilis, and was expressed as percentage of inhibition of PMP bactericidal activity. SIL production was tested by inhibiting lysozyme activity against Micrococcus lysodeikticus and was expressed in microgram per millilitre of inactivated lysozyme. A significantly higher proportion of CPS strains (58.7% vs. 19.2 %) was SIPMP-positive compared with non-CPS strains (P < 0.01). Of the CPS strains tested, 77.8% were SIL-positive compared with 34% of the non-CPS isolates (P < 0.05). These results suggest that the diagnosis of CPS should not rely solely on classical parameters, for example, the identification and counting of microorganisms, but the functional significance of these parameters must be estimated, possibly by the concentration of different bacterial substrains, detection of opportunistic microorganisms with pathogenic properties, such as pronounced resistance to the cationic antimicrobial peptides, and/or the ability to inhibit the antimicrobial host defence factors.

Coryneform bacteria in semen of chronic prostatitis patients

Our aim was to compare the presence and species composition of coryneform bacteria in chronic prostatitis patients and controls. Semen of 50 men with inflammatory prostatitis and 59 controls (without pelvic pain/discomfort complaints and leukocytospermia) was investigated. First-catch urine was additionally investigated in 36 men (30 with and 6 without prostatitis). Coryneform bacteria were found in semen of 76% men with inflammatory prostatitis and 83% controls. More than half of the isolates were identified as Corynebacterium seminale. Prostatitis patients with severe leukocytospermia (>1 million white blood cells per ml) harboured significantly more Corynebacterium group G (33% vs. 2%, p = 0.0003) and Arthrobacter sp. (17% vs. 2%, p = 0.03) in comparison with controls. Nine species of coryneforms with high concentration (>or=10,000 CFU per ml) were found in prostatitis patients as against only four species in controls. Half of the men harboured corynebacteria in semen as well as in urine, 22% of men in semen only, and 3% in urine only. The total concentration of coryneforms was greater in semen than in urine (median 5000 vs. 100 CFU per ml, p = 0.053). We suggest that although coryneforms are generally considered as saprophytes, they are not uniform and some species (Corynebacterium group G and Arthrobacter sp.) may be associated with inflammatory prostatitis.

[The treatment of prostatitis]

PURPOSE

Prostatitis are frequently recognized in general practice and often are a diagnosis and therapeutic challenge. We review here the updated knowledge on diagnosis and therapy of prostatitis.

CURRENT KNOWLEDGE AND KEY POINTS

Prostatitis are divided into acute bacterial prostatitis (I), chronic bacterial prostatitis (II), chronic prostatitis/ chronic pelvic pain syndrome (III) and asymptomatic inflammatory prostatitis. Chronic prostatitis/ chronic pelvic pain syndrome are divided into : inflammatory (IIIA) and noninflammatory (IIIB). Treatment of prostatitis should follow evidence based guidelines recently published. Acute prostatitis should be treated by ciprofloxacine 500 mg tid or ofloxacine 200 mg bid or cotrimoxazole 960 mg bid for 4 weeks (CIII). When bacteremia occurs third generation cephalosporin with gentamicin should be used (CIII). In chronic bacterial prostatitis ciprofloxacine 500 mg tid or ofloxacine 200 mg bid or norfloxacine 400 mg bid or cotrimoxazole 960 mg bid for 4 weeks may be used (BIII).

FUTURE PROSPECTS AND PROJECTS

Molecular techniques should improve the etiological diagnosis of prostatitis and their treatment.

Characteristics of rare or recently described corynebacterium species recovered from human clinical material in Canada

Nineteen new Corynebacterium species or taxa described since 1995 have been associated with human disease. We report the characteristics of 72 strains identified as or most closely resembling 14 of these newer, medically relevant Corynebacterium species or taxa, as well as describe in brief an isolate of Corynebacterium bovis, a rare pathogen for humans. The bacteria studied in this report were nearly all derived from human clinical specimens and were identified by a polyphasic approach. Most were characterized by nearly full 16S rRNA gene sequence analysis. Some isolates were recovered from previously unreported sources and exhibited unusual phenotypes or represented the first isolates found outside Europe. Products of fermentation, with emphasis on the presence or absence of propionic acid, were also studied in order to provide an additional characteristic with which to differentiate among phenotypically similar species.

Identification of Corynebacterium glucuronolyticum strains from the urogenital tract of humans and pigs

Bacterial strains isolated from the genital tracts of humans (predominantly males), semen of boars, and uterine and vaginal secretions of sows were identified as Corynebacterium glucuronolyticum and were compared with the type strains of the recently proposed species Corynebacterium glucuronolyticum and Corynebacterium seminale. The two type strains as well as the clinical strains were shown by DNA-DNA hybridization and sequencing of the 16S rRNA gene to be related at the species level. All strains were classified as C. glucuronolyticum, because this name has nomenclatural priority over C. seminale.

Prostatitis: evolving management strategies

Concepts regarding the etiology, diagnosis, and management of prostatitis have changed more in the last 3 years than they have in the last 3 decades. Urologists (and all physicians) no longer need to avoid patients with this disease. It is hoped that the new management strategies that are evolving will eventually benefit the majority of patients sustaining prostatitis.

Prevalence of corynebacterial 16S rRNA sequences in patients with bacterial and "nonbacterial" prostatitis

The etiology of chronic prostatitis syndromes in men is controversial, particularly when positive cultures for established uropathogens are lacking. Although identification of bacteria in prostatic fluid has relied on cultivation and microscopy, most microorganisms in the environment, including some human pathogens, are resistant to cultivation. We report here on an rRNA-based molecular phylogenetic approach to the identification of bacteria in prostate fluid from prostatitis patients. Positive bacterial signals were seen for 65% of patients with chronic prostatitis overall. Seven of 11 patients with bacterial signals but none of 6 patients without bacterial signals were cured with antibiotic-based therapy. Results indicate the occurrence in the prostate fluid of a wide spectrum of bacterial species representing several genera. Most rRNA genes were closely related to those of species belonging to the genera Corynebacterium, Staphylococcus, Peptostreptococcus, Streptococcus, and Escherichia. Unexpectedly, a wide diversity of Corynebacterium species was found in high proportion compared to the proportions of other bacterial species found. A subset of these 16S rRNA sequences represent those of undescribed species on the basis of their positions in phylogenetic trees. These uncharacterized organisms were not detected in control samples, suggesting that the organisms have a role in the disease or are the consequence of the disease. These studies show that microorganisms associated with prostatitis generally occur as complex microbial communities that differ between patients. The results also indicate that microbial communities distinct from those associated with prostatitis may occur at low levels in normal prostatic fluid.

Prostatitis

The laboratory diagnosis of acute bacterial prostatitis is straightforward and easily accomplished in clinical laboratories. Chronic bacterial prostatitis, and especially chronic idiopathic prostatitis (most often referred to as abacterial prostatitis), presents a real challenge to the clinician and clinical microbiologist. Clinically, the diagnosis of chronic idiopathic prostatitis is differentiated from that of acute prostatitis by a lack of prostatic inflammation and no "significant" (controversial) leukocytes or bacteria in the expressed prostatic secretions. Despite these diagnostic criteria, the etiology of chronic idiopathic prostatitis is unknown. While this review covers the entire spectrum of microbially caused acute prostatitis (including common and uncommon bacteria, viruses, fungi, and parasites) and microbially associated chronic prostatitis, a special focus has been given to chronic idiopathic prostatitis. The idiopathic syndrome is commonly diagnosed in men but is poorly treated. Recent data convincingly suggests a possible bacterial etiology for the condition. Provocative molecular studies have been published reporting the presence of 16S rRNA bacterial sequences in prostate biopsy tissue that is negative for ordinary bacteria by routine culture in men with chronic idiopathic prostatitis. Additionally, special culture methods have indicated that difficult-to-culture coryneforms and coagulase-negative staphylococci are present in expressed prostatic secretions found to be negative by routine culture techniques. Treatment failures are not uncommon in chronic prostatitis. Literature reports suggest that antimicrobial treatment failures in chronic idiopathic prostatitis caused by organisms producing extracellular slime might result from the virulent properties of coagulase-negative staphylococci or other bacteria. While it is difficult to definitively extrapolate from animal models, antibiotic pharmokinetic studies with a murine model have suggested that treatment failures in chronic prostatitis are probably a result of the local microenvironment surrounding the persistent focal and well-protected small bacterial biofilms buried within the prostate gland. These conclusions support the molecular and culture data implicating bacteria as a cause of chronic idiopathic prostatitis.

Prospective study of catalase-positive coryneform organisms in clinical specimens: identification, clinical relevance, and antibiotic susceptibility

During a 6-month period, all clinical isolates of catalase-positive coryneform organisms, which were isolated during the routine processing of clinical specimens, were characterized in the laboratory of the 1800-bed University Hospital of Leuven. The distribution of the species in the corynebacteria was: Corynebacterium amycolatum 70 (53%), Corynebacterium jeikeium 16 (12%), Corynebacterium striatum 11 (8%), Corynebacterium afermentans 10 (7%), Corynebacterium minutissimum 9 (6%), CDC coryneform group G 4 (3%), Corynebacterium urealyticum 4 (3%), Corynebacterium glucuronolyticum 1 (0.7%), and Corynebacterium xerosis 1 (0.7%). Of the 150 isolates, 37 (25%) were considered to be infection related and the remaining 113 (75%) were of questionable clinical significance. Susceptibility of the corynebacteria to 12 antibiotics active against Gram-positive organisms was evaluated. C. amycolatum, C. jeikeium, and C. urealyticum were multiresistant, but all isolates were susceptible to teicoplanin and vancomycin. Most of the C. amycolatum strains, and all strains of C. jeikeium and C. striatum, were susceptible to the vibrocidal compound O/129.

Phylogenetic positions and assignment of swine and ovine corynebacterial isolates based on the 16S rDNA sequence

The nucleotide sequences of the 16S ribosomal RNA gene (rDNA) of swine and ovine corynebacterial strains were determined. The sequences of the strains that identified as Corynebacterium pseudotuberculosis by their biochemical characteristics were homologous with each other. The phylogenetic position of C. pseudotuberculosis strains was closet to C. ulcerans and next closet to C. diphtheriae. The nucleotide sequence of another swine isolate, SC8, was similar to that of a recently proposed species, C. seminale, and a non-validated species, "C. glucuronolyticum," with about 0.01 to 0.02 evolutionary distances. Analysis of the predicted secondary structure of the 16S rRNA molecule agreed with the close phylogenetic relationships between C. pseudotuberculosis and C. ulcerans and between C. seminale and strain SC8.

Microbiology of semen specimens from males attending a fertility clinic

The relationship between semen quality, pyospermia and bacteriology was studied in 201 semen specimens from male patients attending a fertility clinic. Semen quality parameters were within normal limits in 115 (57%) patients, slightly reduced in 60 (30%), and 26 (13%) had findings indicating reduced fertility. Twelve patients (6%) had pyospermia. In 182 patients, 552 microorganisms were detected, including Enterobacteriaceae (2.8%), Gardnerella vaginalis (9.6%), Chlamydia trachomatis (1.6%), Mycoplasma genitalium (0.9%), and Ureaplasma urealyticum (11.8%). Semen quality was neither related to occurrence of microorganisms nor pyospermia. However, pyospermia was associated with simultaneous growth of Gardnerella vaginalis and Ureaplasma urealyticum. The exact nature of this association could not be ascertained, in as far as the males were not questioned about urethritis symptoms.

Clinical microbiology of coryneform bacteria

Coryneform bacteria are aerobically growing, asporogenous, non-partially-acid-fast, gram-positive rods of irregular morphology. Within the last few years, there has been a massive increase in the number of publications related to all aspects of their clinical microbiology. Clinical microbiologists are often confronted with making identifications within this heterogeneous group as well as with considerations of the clinical significance of such isolates. This review provides comprehensive information on the identification of coryneform bacteria and outlines recent changes in taxonomy. The following genera are covered: Corynebacterium, Turicella, Arthrobacter, Brevibacterium, Dermabacter. Propionibacterium, Rothia, Exiguobacterium, Oerskovia, Cellulomonas, Sanguibacter, Microbacterium, Aureobacterium, "Corynebacterium aquaticum," Arcanobacterium, and Actinomyces. Case reports claiming disease associations of coryneform bacteria are critically reviewed. Minimal microbiological requirements for publications on disease associations of coryneform bacteria are proposed.

Species identities and antimicrobial susceptibilities of corynebacteria isolated from various clinical sources

Over a 14-month period, 415 clinical isolates of coryneform gram-positive rods were recovered from various sources and identified to the species level according to recent identification schemes. Corynebacterium urealyticum, Corynebacterium striatum, Corynebacterium amycolatum, and Corynebacterium jeikeium predominated, accounting for 63% of all isolates. Corynebacterium accolens, Corynebacterium striatum, Corynebacterium argentoratense, Corynebacterium propinquum and Corynebacterium pseudodiphtheriticum were mostly recovered from the respiratory tract, whereas Corynebacterium afermentans, CDC group G, and Corynebacterium jeikeium were mainly isolated from blood. None of the isolates was identified as Corynebacterium diphtheriae or Corynebacterium xerosis. Ampicillin resistance was detected in Corynebacterium jeikeium (96%) and Corynebacterium urealyticum (99%) and varied among Corynebacterium amycolatum (56%) and CDC group G (26%). These data emphasize the need for an accurate identification of coryneform organisms at the species level and for antimicrobial susceptibility testing of these organisms.