Comparison of qPCR and culture methods for group B Streptococcus colonization detection in pregnant women: evaluation of a new qPCR assay.

BACKGROUND: Streptococcus Group B (GBS) colonization in pregnant women is the most important risk factor for newborn disease due to vertical transmission during delivery. GBS colonization during pregnancy has been implicated as a leading cause of perinatal infections. Traditionally, pregnant women are screened for GBS between 35 and 37 weeks of gestation. However, antenatal culture-based screening yields no information on GBS colonization status and offers low predictive value for GBS colonization at delivery. Numerous assays have been evaluated for GBS screening in an attempt to validate a fast and efficient method. The aim of this study was to compare bacteria isolation by culture and two qPCR techniques, targeting sip and cfb genes, respectively, for detecting colonizing GBS. METHODS: Cultures - the gold-standard technique, a previous qPCR technique targeting the sip gene, and a new proposed qPCR assay targeting the cfb gene were evaluated as diagnostic tools on 320 samples. RESULTS: Considering cultures as the gold standard, the evaluated qPCR method detected 75 out of 78 samples, representing a sensitivity of 93.58% (95% confidence interval (CI), 90.89-96.27) and specificity of 94.62% (95% CI, 91.78-97.46). However, an additional analysis was performed for true positives that included not only samples showing positives by culture but samples showing positive for both qPCR assays. The sensitivity and specificity were recalculated including these discrepant samples and a total of 89 samples were considered as positive, giving a prevalence of 27.81%. With this new analysis, the qPCR targeting the cfb gene showed a sensitivity of 95.5% (95% CI, 88.65-98.59) and specificity of 99.13% (95% CI, 96.69-99.97). CONCLUSIONS: The new qPCR method is a sensitive and specific assay for detecting GBS colonization and represents a valuable tool for identifying candidates for intrapartum antibiotic prophylaxis. Cultures should be retained as the reference and the routine technique because of its specificity and cost analysis ratio, but it would be convenient to introduce PCR techniques to check negative culture samples or when an urgent detection is required to reduce risk of infection among infants.

Comparison between urine culture profile and morphology classification using fluorescence parameters of the Sysmex UF-1000i urine flow cytometer.

AIMS: To determine the usefulness of the fluorescence parameters generated by Sysmex UF-1000i flow cytometer for the rapid diagnosis of urinary tract infection by bacilli or cocci. METHODS AND RESULTS: Urine samples (n = 1924) were studied by culture and microbiology and subsequently by cytometry, using BACT-Morph software and considering forward-scattered light (FSC) and fluorescent light scatter fluorescence parameters. BACT-Morph software showed moderate diagnostic accuracy (78·4%) to detect rod-shaped bacteria, with sensitivity of 82·4% and specificity of 62·5%. Forward-scattered (B_FSC) values of the bacterial channel were significant higher for the Gram-positive cocci category (P < 0·001). A cut-off of B_FSC ≥24·2, expressed in arbitrary units (analytical channel, ch), provided higher sensitivity (90·0%) but lower specificity (38·9%), and the diagnostic accuracy for Gram-positive cocci classification reached 62·0%. CONCLUSIONS: Utilization of BACT-Morph software and bacterial channel fluorescence parameters (B_FSC ≥24·2 ch) offered an approximate discrimination of bacilli and cocci but the specificity was low, especially for FSC. SIGNIFICANCE AND IMPACT OF THE STUDY: Further research is needed to establish the usefulness of flow cytometry for aetiological diagnosis.

Seroprevalence of Leishmania infection among asymptomatic renal transplant recipients from southern Spain.

BACKGROUND: The aim of this article is to assess the seroprevalence of Leishmania infection among asymptomatic renal transplant recipients in a population in the south of Spain. METHODS: Serum samples were screened for immunoglobulin-G antibodies against Leishmania with an indirect fluorescent antibody test. RESULTS: Of 625 examined serum samples, 30 (4.8%) samples were positive for Leishmania antibodies. Thirteen samples showed titers of 1:80, 15 samples showed titers of 1:160, and 2 samples showed titers of 1:320. None of the patients with positive serology to Leishmania showed signs or symptoms compatible with leishmaniasis. CONCLUSION: The prevalence of Leishmania infection found among asymptomatic renal transplant patients reinforces the need for attention in evaluation of these patients in endemic areas.

Concerning the presumptive identification of Candida kefyr on Uriselect™4 agar.

OBJECTIVE: Non-albicans Candida species, such as Candida kefyr, are emerging pathogens. Chromogenic media are highly useful for the diagnosis of urinary tract infections (UTIs). The aim was to describe the behavior of this specie on a non-specific chromogenic medium. METHODS: A retrospective study of cases of candiduria detected in the Microbiology laboratory of the Virgen de las Nieves Hospital in Granada (Spain) between 2016 and 2021 (N=2,130). Urine samples were quantitatively seeded on non-selective UriSelect™4 chromogenic agar. RESULTS: Between 2016 and 2021, C. kefyr was the seventh most frequent Candida species responsible for candiduria in our setting (n=15). The macroscopic appearance of C. kefyr colonies, punctiform and bluish, allowed the direct identification of these microorganisms. CONCLUSIONS: This study provides the first description of the specific behavior of C. kefyr on UriSelect™4 agar, which differentiates it from other Candida species based on its enzymatic characteristics.

Antimicrobial activity of binary combinations of natural and synthetic phenolic antioxidants against Enterococcus faecalis.

This study investigated the antimicrobial activity of 3 natural (thymol, carvacrol, and gallic acid) and 2 synthetic [butylated hydroxyanisole (BHA) and octyl gallate] phenolic compounds, individually and in binary combinations, on 4 dairy isolates of Enterococcus faecalis with different virulence factors (ß-hemolytic, gelatinase, or trypsin activities; acquired resistance to erythromycin or tetracycline; and natural resistance to gentamicin). A checkerboard technique and a microdilution standardized method were used. All compounds individually tested exhibited antimicrobial activity against E. faecalis, with minimal inhibitory concentrations (MIC) ranging from 30 µg/mL (octyl gallate) to 3,150 µg/mL (gallic acid), although no significant differences were detected among strains to each phenolic compound. Carvacrol in combination with thymol or gallic acid, and gallic acid combined with octyl gallate showed partial synergistic inhibition of all E. faecalis strains. The most effective combinations were thymol+carvacrol and gallic acid+octyl gallate, as the MIC for each of these compounds was reduced by 67 to 75% compared with their respective individual MIC. These results highlight the possibility of using combinations of these phenolic compounds to inhibit the growth of potential virulent or spoilage E. faecalis strains by reducing the total amount of additives used in dairy foods.

[Microbial etiology of bacterial chronic prostatitis: systematic review]. / Etiología microbiana de la prostatitis crónica bacteriana: revisión sistemática.

OBJECTIVE: The importance of Gram-positive microorganisms and atypical bacteria in chronic bacterial prostatitis (CBP) has recently been described. For this reason, this study analyzes the etiology of CBP, as well as the evolution of antibiotic resistance through a systematic review. METHODS: A systematic review of studies obtained through the MEDLINE (PubMed) database, related to the etiology and antibiotic resistance profile of CBP, published up July 1, 2021. RESULTS: The most frequent isolated microorganisms that we have found in publications are Enterococcus faecalis (46.90%), Staphylococcus spp. (22.30%), Escherichia coli (15.09%) and atypical bacteria (6.04%). CONCLUSIONS: CBP is undergoing and unprecedented change of paradigm. Gram-positive bacteria and atypical bacteria are the main pathogens involved in the aetiology of this entity. This forces us to rethink the therapeutic strategy used, since it is necessary to use antibiotics that assume the etiological change and the profile of antibiotic resistance described.

[Shigellosis attended in the emergency department of a regional hospital in southeastern Spain: from their presence to multiresistance]. / Shigelosis atendidas en el servicio de urgencias de un hospital regional del sudeste de España: Desde su presencia a la multirresistencia.

OBJECTIVE: In the bacterial etiology of severe acute infectious diarrhea, except that caused by Clostridioides difficile, most of them have an invasive character and antibiotic treatment will be necessary in specific situations. Shigella is a classic pathogen, in which it is crucial to know the sensitivity to different classic and alternative antimicrobials. The objective of this work was to analyze the presence of shigellosis and the rate of antibiotic resistance. METHODS: A descriptive-retrospective study of the reports of shigellosis of stool cultures issued between January 2016 and April 2022 was conducted. RESULTS: A total of 34 episodes (16 -47.1%- by Shigella sonnei) were observed, as of 2018. There were only 2 pediatric cases. The overall resistance rate to azithromycin, trimethoprim-sulfamethoxazole and ciprofloxacin was 52.9%, 64.7% and 44.1%, respectively. 26.5% were resistant to the 3 groups of antibiotics. There was a higher rate of resistance for S. sonnei. The emergence of resistance to cephalosporins in recent years stands out. Episodes of multidrug-resistant shigellosis were detected between 2020 (1 by S. flexneri) and 2022 (4 by S. sonnei). CONCLUSIONS: The episodes of shigellosis are emerging in our environment with a higher rate of multi-resistance. In this context, current empirical treatments for acute enteroinvasive enteritis are at risk of failure, if necessary.

[Antibiotic resistance changes in episodes of symptomatic bacteriospermia: development in a health area of southeast Spain]. / Cambios en la resistencia antibiótica en episodios de bacteriospermia sintomática: Evolución en un área de salud del sudeste español.

OBJECTIVE: Chronic bacterial prostatitis (CBP) is an entity of difficult clinical diagnosis and treatment, being the microbiological study of semen the main diagnostic test. This study aimed to determine the etiology and antibiotic resistance in patients with symptomatic bacteriospermia (SBP) in our environment. METHODS: A cross-sectional and retrospective descriptive study has been carried out from a Regional Hospital of the Spanish Southeast. The participants were patients assisted in the consultations of the Hospital with clinic compatible with CBP, between 2016 and 2021. The interventions were collection and analysis of the results derived from the microbiological study of the semen sample. The main determinations were the etiology and rate of antibiotic resistance of BPS episodes are analyzed. RESULTS: The main isolated microorganism is Enterococcus faecalis (34.89%), followed by Ureaplasma spp. (13.74%) and Escherichia coli (10.98%). The rate of antibiotic resistance of E. faecalis to quinolones (11%) is lower than previous studies, while for E. coli it has been higher (35%). The low rate of resistance shown by E. faecalis and E. coli to fosfomycin and nitrofurantoin stands out. CONCLUSIONS: In the SBP, gram-positive and atypical bacteria are established as the main causative agents of this entity. This forces us to rethink the therapeutic strategy used, which will avoid the increase in antibiotic resistance, recurrences, and chronicity of this pathology.

Performance of the Sysmex UF1000i system in screening for significant bacteriuria before quantitative culture of aerobic/facultative fast-growth bacteria in a reference hospital.

OBJECTIVE: To evaluate the performance of the Sysmex UF1000i automatic urine screening system in the quantitative culture of fast-growth aerobic/facultative bacteria. METHODS AND RESULTS: A standard procedure was used to recover fast-growth aerobic/facultative micro-organisms in 1225 samples, applying (Sysmex(®)) flow cytometry for parallel bacteria and leucocyte counts. According to the area under the receiver operating characteristic curve, the optimal cut-off values to detect bacteriuria >10(5) colony forming units (CFU) ml(-1) were 690/µl for bacteria and 38/µl for leucocytes (sensitivity, 92%; specificity, 65%; positive predictive value [PPV], 39%; and negative predictive value [NPV], 97%). The use of a single cut-off point of 150 bacteria µl(-1) to detect significant bacteriuria of >10(5) CFU ml(-1) or of ≥10(4) CFU ml(-1) plus leucocyturia obtained similar results (sensitivity, 89%; specificity, 54%; PPV, 31%; and NPV, 96%) and allowed 45.7% of the samples to be rapidly excluded. CONCLUSIONS: The Sysmex UF1000i system can be adapted for bacteriuria screening by the use of an appropriate cut-off point. SIGNIFICANCE AND IMPACT OF THE STUDY: This screening system significantly reduces the workload and produces very few false positives and negatives.

Emergence of genital infections due to Haemophilus pittmaniae and Haemophilus sputorum.

BACKGROUND: We report for the first time the association of Haemophilus pittmaniae and Haemophilus sputorum with urethritis in men who have sex with men and who engage in unprotected intercourse. PATIENTS AND METHODS: A search for genital pathogens was conducted using urethral exudate cultures and PCR tests for Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, Mycoplasma spp., and Ureaplasma spp. Recovered microorganisms were identified by MALDI-TOF mass spectrometry, and their susceptibility was evaluated by diffusion gradient test. RESULTS: H. pittmaniae and H. sputorum were isolated. They both proved susceptible to ampicillin, cefixime, and trimethoprim/sulfamethoxazole. H. pittmaniae was also susceptible to tetracycline and H. sputorum to moxifloxacin. CONCLUSION: The increased frequency of potentially resistant Haemophilus spp. isolates in genital exudates highlights the need for greater surveillance of these microorganisms and for their consideration in the differential diagnosis of genital system infections.

[Sociodemographic characteristics and risk factors associated to significative bacteriuria in a Spanish health area]. / Características sociodemográficas y factores de riesgo asociados a las bacteriurias significativas en un área de salud del sudeste español.

OBJECTIVE: To determine the epidemiological characteristics of significative bacteriuria (SB) and their relationship with sociodemographic factors and to analyze risk factors in inpatients. METHODS: Cross-sectional descriptive study carried out on urine culture samples received between 2016-2020 in the Microbiology laboratory, differentiating between minors and adults. The dependent variable was the presence of SB and the independent variables were age, sex, year, type of sample and source of the sample. In urine cultures of inpatients, risk factors were evaluated from the Minimum Basic Data Set. RESULTS: A total of 68,587 valid records (96.3% of the total) were analyzed. 40.8% (95% CI: 40.4%-41.2%) of urine cultures in adults and 33.8% (95% CI: 32.9%-34.7%) in children were positive, with an incidence that ranged in adults between 18.2 cases/1,000 inhabitants in 2016 and 14.6 cases/1,000 inhabitants in 2020 and 21.1 and 8.4 cases/1,000 inhabitants respectively in minors. Positive urine cultures were more frequent in children from urban areas compared to rural areas (OR=1.37; p<0.01). In hospitalized adults, for each year of age the risk of SB increased by 2%, it was 36% higher in women, 18% higher in obese patients and 17% more frequent in patients with kidney disease, (p<0.01). No relationship was observed between SB and diagnosis of COVID-19. CONCLUSIONS: The sociodemographic characteristics of the population with SB in our health area are similar to those found in other geographical areas worldwide, observing a decreasing trend in incidence in the years studied. The frequency of SB in children is higher in urban areas.

[Infections in patients colonized with carbapenem-resistant Gram-negative bacteria in a medium Spanish city]. / Infecciones en pacientes colonizados con bacterias gramnegativas resistentes a carbapenémicos en una ciudad media española.

OBJECTIVE: Because there are few studies on the clinical implications of colonization by carbapenem-resistant gram-negative bacteria (CRB) this was analyzed in rectal smears (RS) and pharyngeals (PS) and its ability to predict infection/colonization. METHODS: A cross-sectional, retrospective study from adult inpatients between January 2016 and December 2019 was conducted. The isolates were characterized by MicroScan and spectrometry of masses applying EUCAST 2018 cutoff points. The detection of carbapenemases was performed by PCR and Sanger sequencing; sequencies was assigned by MLST. The genetic relationship between the clinical isolates was made by pulsed field electrophoresis using the enzymes Xbal, Spel or Apal. RESULTS: A total of 308 (86.03%) RS and 50 (13.97%) positive PS were detected, the RS had a 85% sensibility, 100% specificity, 100% positive predictive value and 97% negative predictive value. In RS, the following were isolated: 44% (n=135) Acinetobacter baumannii, 26% (n =80) Enterobacterales (20 KPC, 29 OXA-48, 22 VIM, 2 IMP, 7 NDM), 17% (n=53) Pseudomonas aeruginosa and 13% (n=40) Stenotrophomonas maltophilia. In the PS were isolated 44% (n=22) S. maltophilia, 40% (n = 20) A. baumannii, 8% (n=4) P. aeruginosa and 8% (n=4) Enterobacterales (3 VIM, 1 OXA). From the patients with simultaneous RS and PS, 41 (40.6%) had positivity in both smears, 45 (44.6%) only in RS and 15 (14.9%) only in PS. Colonization preceded infection in 81.3% (n=13) of the isolates; association between infection and colonization was found (p<0.001; χ2); and the episodes where the information was found all the isolates from the clinical samples and from the smears were similar. CONCLUSIONS: The probability of predicting infection through the CRB colonized in different clinical samples is feasible. The RS has a major sensibility to detect colonization.

[Increased infections by herpes simplex virus type 1 and polymicrobials of the genital tract, in the general population of a Spanish middle city]. / Aumento de las infecciones por virus del herpes simple tipo 1 y polimicrobianas del aparato genital, en la población general de una ciudad media española.

OBJECTIVE: Infections by genitopathogens are a frequent reason for consultation in Primary Health Care and in the specialties of Infectious Diseases, Urology, Gynecology, and Dermatology. The most common causes are opportunistic microorganisms and responsible for sexually transmitted infections associated with unprotected sex. The objective is to determine the microorganisms that cause these infections in patients treated at the Hospital Universitario Virgen de las Nieves in Granada and Neisseria gonorrhoeae susceptibility to antibiotics. METHODS: A transversal-descriptive and retrospective study was carried out, which included the results issued, between January 2018 and December 2019, in the Microbiology Laboratory from all the episodes studied using standardized working procedures. RESULTS: The most frequently detected microorganisms were Gardnerella vaginalis (23.81%) followed by Candida spp. (20.9%), especially in females, and N. gonorrhoeae (11.36%) and Ureaplasma urealyticum (11.99%), in males. Many times, they were presented in combination. Regarding herpes simplex viruses, infection by both species had a similar prevalence (50%) in males, while type 1 was more prevalent (76.52%) in females. The most active antibiotics against N. gonorrhoeae were cefotaxime (98%) and cefixime (100%). Tetracycline (39.02%) a poorly active antibiotic. CONCLUSIONS: The most frequent pathogens corresponded to those that usually caused infections in females, although N. gonorrhoeae was the most frequent in males and mixed infections are not an accidental finding. HSV-1 infections were more frequent than HSV-2, confirming the trend of a change in the epidemiology of genital herpes.

[Prevalence among males from the general population of agents responsible of not ulcerative genital tract infections, assisted in specialized care]. / Prevalencia en varones de la población general de agentes productores de infecciones no ulcerativas del aparato genital, asistidos en atención especializada.

OBJECTIVE: Male genital infections are a major problem due to their high frequency and morbidity and their role in cases of male infertility. We studied the presence, in males assisted in specialized care, of non-ulcerative genital tract infections-producing agents. METHODS: We studied descriptively and retrospective microbiological results of 3,066 samples of male patients, with diagnosis of genital tract infection episode, received between January 1, 2016 and December 31, 2017. Detection of microorganisms in the sample was performed using techniques of artificial culture and PCR (BD-MAX). RESULTS: Positive results were obtained in 451 samples (14.71%). By culture, the most frequent pathogens were Enterobacterales (18.40%), Enterococcus (13.75%), Haemophilus (8.65%), Neisseria gonorrhoeae (8.43%), Ureaplasma (5.10%), and Candida (3.77%). By polymerase chain reaction (PCR), the most frequent were N. gonorrhoeae (28.37%), Chlamydia trachomatis (26.95%), Ureaplasma urealyticum (17.73%), Mycoplasma hominis/Ureaplasma parvum (10.64%), and Mycoplasma genitalium (7.10%). The age was older in patients infected with Enterobacterales, Candida, or Enterococcus and younger in those infected with N. gonorrhoeae. CONCLUSIONS: N. gonorrhoeae and C. trachomatis are still more common in male genital infection pathogens, although other culturable microorganisms have an important role. These findings demonstrate the importance of systematically applying both conventional culture and PCR techniques for pathogen detection.

Evolution of the antibiotic-resistance of microorganisms causing urinary tract infections: A 4-year epidemiological surveillance study in a hospital population. / Evolución de la resistencia a antibióticos de microorganismos causantes de infecciones del tracto urinario: un estudio de vigilancia epidemiológica de 4 años en población hospitalaria.

BACKGROUND: Urinary tract infections (UTIs) are the leading cause of infection in hospitalised patients. In this study, we describe the most common pathogens involved in the development of UTIs in hospitalised patients, their antibiotic-sensitivity profile and the activity evolution of antibiotics in standard use for treating these infections. METHODS: We retrospectively assessed the results of cultures and antibiograms from urine samples from adult patients hospitalised in the Hospital Complex Virgen de la Nieves (Granada, Spain) with a microbiological confirmation of UTI between January 2013 and December 2016. RESULTS: We identified 4,347 microorganisms (3,969 bacteria and 378 yeasts). During the 4years of the study, Escherichia coli was the most common species isolated in both sexes; however, 62.9% of the UTIs were caused by other microorganisms. The presence of multiresistant microorganisms such as Acinetobacterspp. (1.2%) and extended-spectrum beta-lactamase-producing enterobacteria (10.0%) and carbapenemase-producing enterobacteria (0.3%) were also relevant findings. Imipenem, piperacillin-tazobactam and fosfomycin presented activity rates above 80%, considering all causal microorganisms of UTI, while the other tested antibiotics presented activity rates below 70%. CONCLUSION: Imipenem and piperacillin-tazobactam were the most active antibiotics in hospital use, which makes them first-line antibiotics in the empiric treatment of UTIs in this healthcare setting. The use of other antibiotics should be limited to conditions of demonstrated or highly probable sensitivity.

[Comparison of intrathecal fentanyl and bupivacaine in combined spinal-epidural obstetric analgesia]. / Comparación del efecto de fentanilo frente a bupivacaína intratecal en una técnica anestésica combinada durante la analgesia obstétrica.

OBJECTIVES: To compare intrathecal injection of the opioid fentanyl to injection of bupivacaine, in terms of their effect of labour in the context within the combined spinal-epidural analgesia. METHODS: Prospective single-blind trial in primiparas randomized to 2 groups for sedation with 25 microg of fentanyl or 2.5 mg of bupivacaine, followed in both cases by epidural infusion of ropivacaine. We measured time from puncture to delivery of the neonate, rescue analgesia, pain assessed on a visual analog scale (VAS), motor block, side effects, sensory level, Apgar score, and maternal satisfaction. RESULTS: Sixty-four women were studied. The mean time elapsed between puncture and birth was 168.59 minutes (95% confidence interval [CI], 134.16 to 203.03 minutes) in the bupivacaine group and 189.13 minutes (95% CI, 151.93 to 226.32 minutes) in the fentanyl group. The mean difference was -20.53 minutes (95% CI, -70.21 to 29.15 minutes). Survival analysis applied to duration of labor, using type of delivery as the final outcome, also failed to show a significant between-group difference (chi2=0.59, P=.447). No significant differences in use of rescue analgesia, VAS scores, or motor block were observed. The incidence of pruritus in the fentanyl group was 34.37%, but there were no differences in maternal satisfaction. CONCLUSIONS: Our findings do not support the use of intradural fentanyl with the aim of shortening labor. Fentanyl leads to more pruritus, although this side effect does not affect maternal satisfaction.

First clinical isolation report of Shewanella algae from the stools of a patient with acute enteritis in Spain.

We report a case of acute enteritis caused by Shewanella algae in a cirrhotic patient. Biochemical identification systems revealed to be insufficient to identify the Shewanella isolate at the species level, thus requiring 16S rRNA and gyrB partial gene sequencing. Even if co-infection by Clostridium difficile could not be ruled out, this is, to our knowledge, the first report of acute enteritis caused by Shewanella algae in Europe.

Urinary tract infection by aerococcus sanguinicola. An emerging opportunistic pathogen. / Infección urinaria por Aerococcus sanguinicola. Patógeno emergente oportunista.

Elderly patients with underlying urological disease have a greater risk of urinary tract infections due to uncommon pathogens. The disease caused by Aerococcus has been underestimated, but mass spectrometry could be a simple method for identifying this pathogen. In this study, we report 2 cases of urinary tract infection by Aerococcus sanguinicola. A descriptive clinical-microbiological study was conducted on the presence of A. sanguinicola causing urinary tract infections. The presence of A. sanguinicola occurred in elderly patients with previous urological disease and a significant count in urine obtained through bladder catheterisation. Correct identification was achieved through mass spectrometry, and the clinical outcome of administering amoxicillin and cefuroxime was satisfactory. In this study, we also report the pathogenic capacity of A. sanguinicola. When there is a significant number of alpha-haemolytic microorganisms in the urine cultures, A. sanguinicola should be ruled out before reporting a result as urogenital microbiota.