The role of bacterial genital infections in spontaneous preterm delivery: a case-control study.

Background: Spontaneous preterm delivery is defined as the beginning of the birth process before the 37th week of pregnancy. The presence of microorganisms in the fetal membranes is accompanied by an increase in the production of prostaglandin, one of the important factors associated with the prevalence of preterm birth. The invasion of microorganisms leads to the production of protease, coagulase, and elastase, which directly stimulate the onset of childbirth. We investigated the role of genital infections in women with preterm birth. Methods: The present case-control study was conducted in the west of Iran on 100 women with spontaneous preterm delivery (following 24 weeks of gestation and before 36 weeks and 6 days) as the case group and 100 women with normal delivery as controls. A questionnaire was applied to collect the data. Polymerase chain reaction and pathological examination of the placenta were performed. Results: The average age in women with normal delivery (30.92 ± 5.10) in women with spontaneous preterm delivery (30.27 ± 4.93). The prevalence of Chlamydia trachomatis, Neisseria gonorrhea, Listeria monocytogenes, and Mycoplasma genitalium infections was zero in both groups. The highest prevalence of Gardnerella vaginalis was 19 (19%) in the case group and Ureaplasma parvum 15 (15%) in the control group. Also, Placental inflammation was zero in controls and 7(7%) in the patient group. There was a significant relationship between Gardnerella vaginalis bacteria and spontaneous preterm delivery. Conclusion: The results of our study showed that except for Gardnerella vaginalis bacteria, there is no significant relationship between the above bacterial infections and spontaneous preterm birth. Moreover, despite the significant reduction in the prevalence of many sexually transmitted infections in this research, it is still suggested to increase the awareness of people, including pregnant women, about the ways it can be transmitted by gynecologists and health and treatment centers.

A comparative study on antibiotic resistance and virulence properties of Staphylococcus aureus isolated from hospitalized patients and hospital environment.

BACKGROUND: We compared the characteristics of clinical Staphylococcus aureus and S. aureus isolated from environmental surfaces in 3 hospitals. METHODS: Clinical S. aureus isolates were collected from hospitalized patients. Environmental surfaces were sampled from the rooms of patients infected with S. aureus. After identifying rooms with the target organism, 3-5 high-touch surfaces in patient care areas were sampled using swabs before room cleaning by environmental services. S. aureus isolates were subjected to genotyping, antimicrobial susceptibility testing, and virulence determinant screening. The isolates were analyzed for integron content and sequences of variable region amplification products. RESULTS: There were epidemiologically unrelated 79 clinical and 62 environmental S. aureus isolates. Overall, 11.4% of clinical and 59.7% of environmental isolates were methicillin-resistant. The environmental and clinical S. aureus exhibited very different virulence profiles: 79% of the environmental isolates were negative for virulence genes compared to 2.5% of clinical isolates (P < .001). Environmental isolates were more resistant to antibiotics compared to clinical isolates. Class 1 integrons were only detected in 7 of 62 environmental isolates, of which 3 isolates had integrons with cysteine synthase cassette, 1 had aadA1, and 1 had an unknown cassette. CONCLUSION: These data indicate the different characteristics between environmental and clinical S. aureus, which may reflect different reservoirs from which the 2 groups acquired the strains.

Prevalence of Listeria monocytogenes infection in women with spontaneous abortion, normal delivery, fertile and infertile.

BACKGROUND: Listeria monocytogenes with a vast range of natural reservoirs is more known for being a food-borne pathogen. Human infections have shown an impact on pregnancy outcomes, so, this study surveyed the frequency of L. monocytogenes infection involving different groups of women. METHODS: This study enrolled a total sample consisting of 109 women with spontaneous abortion, 109 women with normal delivery, 100 fertile women, and 99 infertile women aged 19-40 years and willing to participate in the study. The research tool in this study was a questionnaire and Polymerase chain reaction (PCR) test. RESULTS: According to the results, the frequency of L. monocytogenes infection was 4/109 (3.66%) observed among women with spontaneous abortion, 2/109 (1.83%) among women with normal delivery, 3/100 (3%) among fertile women, and 0/99 (0%) among infertile women. CONCLUSION: There was no significant relationship between Listeria monocytogenes infection and pregnancy outcomes of spontaneous abortion and infertility.

Virulence genes, phylogenetic analysis, and antimicrobial resistance of Escherichia coli isolated from urinary tract infection in hospitalized patients and outpatients.

Uropathogenic Escherichia coli (UPEC) strains are the most common cause of urinary tract infection (UTI) in hospitalized and community patients. The aim was to compare the genetic characteristics of E. coli isolated from inpatients (IPs) and outpatients (OPs) with UTI regarding their phylogenies, virulence traits, and resistance trends. In this cross-sectional study, 130 epidemiologically unrelated E. coli isolates were collected from patients with UTI. Extended-spectrum beta-lactamase (ESBL) production was detected by the combination disk method. UPEC and intestinal pathogenic E. coli (IPEC) virulence genes were detected by polymerase chain reaction. The isolates were analyzed for phylogenetic grouping. A P value of < 0.05 was considered significant. Of the 130 isolates, 62.3% were from OPs and 37.7% from IPs. About 35.8% of the OPs and 49% of the IPs were ESBL positive. Moreover, 56.8% of the OPs and 59.2% of the IPs were positive for UPEC virulence genes. Notably, 50% of the isolates from each group exhibited IPEC virulence properties. The predominant phylogroup was B2 (43.2% in the OPs and 40.8% in the IPs). No significant difference was found between the IP and OP isolates (P > 0.05). Our results may indicate that consideration should also be given to hygienic standards in the community. The marked genetic plasticity of E. coli has allowed the emergence of strains showing arrays of genes from different pathotypes. Characterization of E. coli isolates in different areas may guide the selection of effective infection control strategies.

Characterization of Escherichia coli isolated from urinary tract infection and association between virulence expression and antimicrobial susceptibility.

BACKGROUND: The capacity of antibiotics to modulate bacterial virulence has raised concerns over the appropriateness of antibiotic therapies, including when dosing strategies fall below sub-therapeutic levels. In this work, we investigated the ability of antibiotics to influence virulence in Escherichia coli isolated from urinary tract infection (UTI). RESULTS: Out of 120 isolates, 32.5% carried pap, 21.7% carried hlyA, and 17.5% carried cnf. The predominant B2 phylogroup was significantly associated with the quinolone-resistant isolates. A significant association was seen between the presence of hlyA hemolysin and susceptibility to ceftriaxone and ciprofloxacin (P < 0.05). Sub-inhibitory concentrations of both antibiotics reduced the levels of hlyA expression and hemolysis in isolates treated with antibiotics compared to untreated isolates (P < 0.05). Growth rate assay showed that the decrease in hlyA expression was not an effect of decreased growth rate. CONCLUSION: Our study indicated the inhibitory effect of ciprofloxacin and ceftriaxone on the level of hemolysis, suggesting that the sub-inhibitory concentrations of these antibiotics may affect the outcome of infections. Further studies, including animal models may elucidate the outcome of virulence modulation by these antibiotics in UTI pathogenesis.

Antibiotic susceptibility of human-associated Staphylococcus aureus and its relation to agr typing, virulence genes, and biofilm formation.

BACKGROUND AND OBJECTIVE: Carriage of virulence factors confers some evolutionary benefit to bacteria, which favors the resistant strains. We aimed to analyze whether antibiotic susceptibility of Staphylococcus aureus strains is affected by agr typing, biofilm formation ability, and virulence profiles. METHODS: A total of 123 S. aureus clinical isolates were subjected to antimicrobial susceptibility testing by disk diffusion method, biofilm formation by microtiter plate method, as well as polymerase chain reaction screening to identify virulence genes and the accessory gene regulator (agr) types I-IV. A P value < 0.05 was considered significant. RESULTS: The most prevalent virulence gene was staphyloxanthin crtN, followed by hemolysin genes, capsular cap8H, toxic shock toxin tst, and enterotoxin sea, respectively. Resistant isolates were more commonly found in the agr-negative group than in the agr-positive group. Isolates of agr type III were more virulent than agr I isolates. Strong biofilm producers showed more antibiotic susceptibility and carried more virulence genes than non-strong biofilm producers. Associations were found between the presence of virulence genes and susceptibility to antibiotics. Carriage of the virulence genes and agr was higher in the inpatients; while, resistance and strong biofilms were more prevalent in the outpatients. CONCLUSION: These findings indicated the presence of several virulence factors, biofilm production capacity, agr types and resistance to antibiotics in clinical S. aureus isolates. Considering the importance of S. aureus for human medicine, an understanding of virulence and resistance relationships would help to reduce the impact of S. aureus infections.

High frequency of enterotoxin encoding genes of Staphylococcus aureus isolated from food and clinical samples.

BACKGROUND: Staphylococcus aureus is recognized as an important cause of food poisoning related to the consumption of raw, undercooked, or mishandled foods worldwide. METHODS: A total of 90 individual meat samples and 200 clinical specimens were collected and investigated the frequency of S. aureus and classical enterotoxin genes. The samples were cultured on Baird-Parker and Mannitol salt agar and subjected for confirmatory biochemical tests and molecular detection of femA, sea, seb, sec, sed, and see genes. RESULTS: A total of 31 (34.5%) meat samples and 81 (40.5%) clinical specimens were positive for the presence of S. aureus. These isolates were detected with slightly higher frequency in clinical specimens than food samples (P> 0.05). Furthermore, the frequency of S. aureus in raw meat (23.4%) was higher than that in cooked meat samples (11.1%) (P< 0.05). Staphylococcal enterotoxin (SE) genes were identified in 18 (58.1%) of 31 meat isolates and 42 (51.8%) of 81 clinical isolates. The frequency of SE genes (except see) in meat isolates was slightly higher than that in clinical isolates (P> 0.05). We found sea and see genes with higher frequency than others in both meat and clinical samples. Furthermore, 55.5% of meat isolates and 38.1% of clinical isolates possessed more than one se gene. CONCLUSION: Detection of enterotoxigenic S. aureus in clinical and raw meat samples shows a probable risk for public health. Therefore, intensive and continuous monitoring of potentially pathogenic S. aureus is strongly recommended in order to evaluate the human health risk arising from food consumption.

Antibiotic resistance and typing of agr locus in Staphylococcus aureus isolated from clinical samples in Sanandaj, Western Iran.

OBJECTIVES: Infections by Staphylococcus aureus remain an important health problem. The aims were to detect mecA, staphylococcal cassette chromosome mec (SCCmec), accessory gene regulator (agr), and integrons in S. aureus and to investigate the relationship of agr types with antibiotic resistance of isolates. MATERIALS AND METHODS: In this cross-sectional study, 70 S. aureus isolates were collected between December 2017 and May 2018 from clinical specimens of patients in two hospitals of Sanandaj, western Iran. Susceptibility was determined by disk diffusion for 9 antibiotics and by vancomycin E test. The mecA, classes 1-3 integrons, SCCmec I-V, and agr I-IV were detected by polymerase chain reaction. A P-value<0.05 was considered significant. RESULTS: The most effective antibiotics were linezolid, vancomycin, and trimethoprim-sulfamethoxazole (above 90% sensitivity). Of the 70 isolates, 17.1% were methicillin-resistant S. aureus (MRSA), 8.6% carried class 1 integron, 11.4% carried mecA, 17.1% carried agr I, and 30% carried agr III. SCCmec III and SCCmecV were detected. An association was found between resistance to certain antibiotics and the presence of agr I (P-value<0.05). Conversely, the prevalence of agr III in susceptible strains was higher than non-susceptible strains, and no MRSA isolates belonged to agr III (P-value<0.05). CONCLUSION: These data suggest that agr activity may influence the resistance of S. aureus to antibiotics. Although the prevalence of mecA and integron was relatively low, the identification of such strains calls for serious health concerns; thus highlights the need to monitor drug resistance in S. aureus.

Study on the presence of resistant diarrheagenic pathotypes in Escherichia coli isolated from patients with urinary tract infection.

AIM: This article aimed to analyze the diarrheagenic potential of E. coli isolated from urinary tract infection (UTI) and to recognize the presence of antibiotic resistance genes. BACKGROUND: The marked genome plasticity of Escherichia coli has allowed the emergence of resistant pathogenic strains displaying an unusual arrangement of genes. METHODS: In this cross-sectional study, 110 E. coli were isolated from patients with the symptoms of UTI in Sanandaj, west of Iran between July and September - 2015. The isolates were examined by the disk diffusion method for antibiotic susceptibility test and by polymerase chain reaction for the presence of genes characteristic of diarrheagenic E. coli (DEC), Uropathogenic E. coli (UPEC) virulence genes, extended-spectrum ß-lactamase bla CTX-M and plasmid-mediated quinolone resistance determinants, qnrA, qnrB, and qnrS. RESULTS: The most and the least effective antibiotics were nitrofurantoin and cefotaxime (96.4% and 27.3% sensitivity, respectively). Of the 110 UTI isolates, 57.3% carried diarrheagenic genes. The bundle-forming pilus bfpA was the most prevalent diarrheagenic gene (39.1%). The most commonly detected DEC pathotype was enterotoxigenic E. coli (-ETEC, 12.7%). All the pathotypes carried the bla CTX-M and qnr. The -UPEC hly hemolysin and pap adhesin genes were mainly detected among ETEC isolates. CONCLUSION: Our results indicated the presence of resistant diarrheagenic pathotypes in UTI-associated E. coli. Such isolates may have the capacity of causing both extraintestinal and intestinal infections. Based on our knowledge, this is the first report of the presence of qnr in ETEC from urine.

A PRISMA systematic review and meta-analysis on Chlamydia trachomatis infections in Iranian women (1986-2015).

BACKGROUND: Chlamydia trachomatis (CT) is the cause of genital tract infections in women. Some evidence has shown the role of this infection with CT in spontaneous abortions. The purpose of this study is to study the frequency of CT infection in Iranian women. METHODS: This study was performed based on PRISMA guidelines. A total of 75 articles published in Google Scholar, PubMed, ISI Web of Science, Biological abs, Iranmedex, SID, and Scopus databases were found (1986-2015) using the following keywords: CT in women, CT and Iranian women, CT and infection in Iran, CT and pregnancy in Iran, CT and preterm delivery in Iran, CT and preterm labor in Iran, CT and fertility in Iran, CT and infertility in Iran, and CT and abortion in Iran. Finally, 40 studies from different regions of Iran were included. Statistical analyses were performed using R3 and STATA 12. RESULTS: From 1986 to 2015, the lowest rate of prevalence was from 2010 to 2011 (3.9%) and the highest prevalence rate was in 2009 (69.39%) in northern Iran. Fixed effects for different parts of Iran (North, South, East, and West) were Pooled proportion: 0.13 (95% confidence interval [CI] = 0.12-0.14) and for samples (cervical, vaginal, urine, and blood) the pooled proportion was = 0.14 (95% CI = 0.12-0.14). CONCLUSION: CT infection in this study was prevalent in urine samples and the rate of CT was observed from culture methods in comparison to other methods. Because women with CT play an important role because of sexual activity for transmission and untreated women are at risk of developing sequels. Also, most studies in Iran use sensitive polymerase chain reaction tests for the detection of genital CT infections.

Multiple-Locus Variable Number Tandem Repeat Analysis of Klebsiella pneumoniae: Comparison with Pulsed-Field Gel Electrophoresis.

AIM: To assess whether multiple-locus variable-number tandem repeat analysis (MLVA) could replace pulsed-field gel electrophoresis (PFGE) for genotyping of Klebsiella pneumoniae, this study was conducted to compare the typeability, discriminatory power, and concordance of these methods. MATERIALS AND METHODS: We used the nine variable number tandem repeat (VNTR) loci scheme to test its suitability for differentiating 114 ESBL-producing K. pneumoniae isolates collected from different clinical specimens in three hospitals of Tehran, Iran between April and December 2011. PFGE with XbaI was performed and the results were compared with those obtained by typing with MLVA. RESULTS: MLVA and PFGE yielded 44 and 64 types, respectively. Simpson's Diversity Index of MLVA was 0.896 (a 95% confidence interval of 0.850-0.942) and of PFGE was 0.962 (a 95% confidence interval of 0.943-0.981). Congruence between PFGE and MLVA was low. The adjusted Wallace coefficient of PFGE to MLVA was 0.946; however, MLVA was less able to predict PFGE type (32.5%). A range of 2-12 alleles was identified at VNTR loci with Simpson's diversity values between 0.017 and 0.818. CONCLUSION: MLVA is a PCR-based typing method and is much easier and more rapid in comparison to PFGE. These data indicate that the MLVA typing scheme used in this study is discriminative and reliable for typing of K. pneumoniae. However, optimization of the VNTR markers is required to improve the discriminatory power of the method.

Association Between Presence of Virulence Genes and Antibiotic Resistance in Clinical Klebsiella Pneumoniae Isolates.

OBJECTIVE: To investigate the presence of rmpA and wcaG virulence genes and Class 1, 2, and 3 integrons, and to evaluate a relationship between antibiotic resistance and virulence in Klebsiella pneumoniae METHODS: We collected a total of 200 K. pneumoniae isolates from hospitals in Tehran, Iran. Antibiotic susceptibility was determined using the disk diffusion method. The extended-spectrum ß-lactamase (ESBL) producers were detected using the combination disk method. We detected the rmpA and wcaG genes and class 1, 2, and 3 integrons via polymerase chain reaction (PCR). The χ2 test was used for statistical evaluation. RESULTS: Of 200 isolates, 115 (57.5%) were ESBL producers; 74.0% carried the class 1 integron, and 1.0% carried the class 2 integron. The gene rmpA was detected in 7% of isolates and the gene wcaG in 23.5% of isolates. Integron-positive isolates showed a higher prevalence of wcaG compared with to integron-negative isolates (P <.05). CONCLUSION: Our results showed a correlation between presence of virulence gene and antibiotic resistance in K. pneumoniae.

Genotyping and characterization of CTX-M-15 -producing Klebsiella pneumoniae isolated from an Iranian hospital.

The aims were to describe the genetic characterization of blaCTX-M-1 group gene in Klebsiella pneumoniae and to investigate the relationship between isolates by MLVA and PFGE. We analyzed 36 CTX-M group 1-ESBL producing K. pneumoniae. rmpA and wcaG virulence genes were identified by PCR. The genetic environment of blaCTX-M-1 was analyzed by PCR and sequencing. Plasmid replicons were determined using PCR-based replicon typing. The isolates were typed by MLVA and PFGE. All blaCTX-M-1 were blaCTX-M-15. The wcaG and rmpA were detected in 1 and 2 isolates, respectively. IncF were the most frequently detected replicons (63.88%). In all isolates, ISEcp1 was found upstream and orf477 downstream of blaCTX-M-15, IS26 was found in two isolates. MLVA identified 20 MLVA types, whereas PFGE identified 25 different profiles. The dissemination of CTX-M-15 in our isolates was due to the clonal spread of isolates and to the genetic transfer of mobile elements among unrelated strains.

Effect of cumin (Cuminum cyminum) seed essential oil on biofilm formation and plasmid Integrity of Klebsiella pneumoniae.

Seeds of the cumin plant (Cuminum cyminum L.) have been used since many years in Iranian traditional medicine. We assessed the effect of cumin seed essential oil on the biofilm-forming ability of Klebsiella pneumoniae strains and on the integrity of a native resistance plasmid DNA from K. pneumoniae isolates, treated with essential oil. Antibacterial coaction between the essential oil and selected antibiotic disks were determined for inhibiting K. pneumoniae. The essential oil of the cumin seeds was obtained by hydrodistillation in a Clavenger system. A simple method for the formation of biofilms on semiglass lamellas was established. The biofilms formed were observed by scanning electron microscopy (SEM). The effect of essential oil on plasmid integrity was studied through the induction of R-plasmid DNA degradation. The plasmid was incubated with essential oil, and agarose gel electrophoresis was performed. Disk diffusion assay was employed to determine the coaction. The essential oil decreased biofilm formation and enhanced the activity of the ciprofloxacin disk. The incubation of the R-plasmid DNA with essential oil could not induce plasmid DNA degradation. The results of this study suggest the potential use of cumin seed essential oil against K. pneumoniae in vitro, may contribute to the in vivo efficacy of this essential oil.

Effect of subinhibitory concentrations of cumin (Cuminum cyminum L.) seed essential oil and alcoholic extract on the morphology, capsule expression and urease activity of Klebsiella pneumoniae.

Cuminum cyminum L., commonly known as cumin, is a plant with a considerable reputation. The aim of this work was to study the activity of cumin seed essential oil and alcoholic extract against Klebsiella pneumoniae ATCC 13883 and clinical K. pneumoniae isolates by evaluating the effect of subminimum inhibitory concentrations (sub-MICs) on cell morphology, capsule expression and urease activity. Growth of K. pneumoniae strains exposed to sub-MICs of C. cyminum extracts resulted in cell elongation and repression of capsule expression. Urease activity was decreased. The major constituent of the oil determined by gas chromatography/mass spectrometry was cumin aldehyde.