Phylogenetic Distribution of CRISPR-Cas Systems in Staphylococcus lugdunensis.

Clustered regularly interspaced short palindromic repeats (CRISPRs) and CRISPR-associated (Cas) genes (CRISPR-Cas) are present in many bacterial genomes with functions beyond adaptive immunity. We aimed to characterize the CRISPR-Cas system in the pathogenic Gram-positive bacterium Staphylococcus lugdunensis and determine its association with sequence types (STs) determined by multilocus sequence typing (MLST) and oxacillin susceptibility. Primers were designed to detect and sequence types IIIA and IIC CRISPR-Cas in 199 S. lugdunensis isolates. MLST and oxacillin susceptibility tests were also performed on the isolates. We found that 84 S. lugdunensis isolates had type IIIA CRISPR-Cas, while 46 had type IIC. The results showed a strong association between STs and CRISPR-Cas types. The ST1, ST6, ST12, and ST15 isolates had type IIIA CRISPR-Cas systems, and the ST4, ST27, and ST29 isolates had type IIC CRISPR-Cas. Interestingly, of 83 isolates containing type IIIA CRISPR-Cas, 17 (20.5%) were oxacillin-resistant S. lugdunensis (ORSL), and all of these ORSL isolates belonged to ST6 cluster 1. Moreover, spacers 23 and 21 were found in 16 and 17 ORSL isolates, respectively. In contrast, all 46 isolates with type IIC CRISPR-Cas were susceptible to oxacillin. Our results showed that 41.3% of CRISPR-Cas IIIA spacers were homologous to plasmids and 20.2% were homologous to phages. However, in type IIC CRISPR-Cas, 11.8% and 39.9% of spacers showed sequence homology with plasmids and phages, respectively. In conclusion, we found that the distribution and composition of the CRISPR-Cas system in S. lugdunensis was associated with STs and oxacillin susceptibility. IMPORTANCE CRISPR-Cas systems have been characterized as playing several biological roles in many bacterial genomes. Moreover, CRISPR-Cas systems are useful for epidemiological, diagnostic, and evolutionary studies of pathogenic bacteria. However, the characteristics of CRISPR-Cas systems in Staphylococcus lugdunensis have been rarely reported. In this study, we revealed that type IIIA CRISPR-Cas was dominant in S. lugdunensis isolates, followed by type IIC CRISPR-Cas. Moreover, the composition of CRISPR-Cas spacers was strongly associated with multilocus sequence typing and oxacillin susceptibility of S. lugdunensis. These results advance our understanding of the evolution of CRISPR-Cas systems; however, the biological functions of CRISPR-Cas systems in S. lugdunensis remain to be further characterized.

Infectious diseases specialist consultation in Staphylococcus lugdunensis bacteremia.

BACKGROUND: Commensal coagulase negative Staphylococcus lugdunensis may cause severe bacteremia (SLB) and complications. Treatment of SLB is not fully established and we wanted to evaluate if infectious diseases specialist consultation (IDSC) would improve management and prognosis. METHODS: Multicenter retrospective study of SLB patients followed for 1 year. Patients were stratified according to bedside (formal), telephone (informal) or lack of IDSC within 7 days of SLB diagnosis. RESULTS: Altogether, 104 SLB patients were identified: 24% received formal bedside and 52% informal telephone IDSC whereas 24% were managed without any IDSC. No differences in demographics, underlying conditions or severity of illness were observed between the groups. Patients with bedside IDSC, compared to telephone IDSC or lack of IDSC, had transthoracic echocardiography more often performed (odds ratio [OR] 4.00; 95% confidence interval [CI] 1.31-12.2; p = 0.012) and (OR 16.0; 95% CI, 4.00-63.9; P<0.001). Bedside IDSC was associated with more deep infections diagnosed compared to telephone IDSC (OR, 7.44; 95% CI, 2.58-21.4; p<0.001) or lack of IDSC (OR, 9.56; 95% CI, 2.43-37.7; p = 0.001). The overall mortality was 7%, 10% and 17% at 28 days, 90 days and 1 year, respectively. Considering all prognostic parameters, patients with IDSC, compared to lack of IDSC, had lower 90 days and 1 year mortality (OR, 0.11; 95% CI, 0.02-0.51; p = 0.005) and (OR, 0.22; 95% CI, 0.07-0.67; p = 0.007). CONCLUSION: IDSC may improve management and outcome of Staphylococcus lugdunensis bacteremia.

The role of Staphylococcus lugdunensis as a pathogen in children: a multicentre retrospective study.

Introduction: Staphylococcus lugdunensis (SL), a tube coagulase negative Staphylococcus, is known to be pathogenic in adults, causing mainly skin infections.Gap Statement: Previous studies assessing SL's role in paediatric populations are sparse and are mainly limited to case reports.Aim: Present the clinical characteristics consistent with SL infections and its putative role as a pathogen in the paediatric population.Methodology: A retrospective multicentre study was conducted in four paediatric medical centres in Israel. Patients with isolates of SL presenting between 2009-2019 were included.Results: SL was isolated from 40 patients. Average (±SD) age at presentation was 5.9 (±6.2) years, with 22 (55 %) being female. Skin, soft tissue and musculoskeletal infections were the most common (n=20, 50%) followed by ear infections (n=13, 32.5%). Five cases of urine isolates and two isolates from blood culture samples were also reported. Skin abscess was the most common infection among skin and soft tissue isolates, reported in 17 children (85%) with SL being the only pathogen in 15 (75%). Otitis media was the most common ear infection accounting for 12 (92%) of all cases with SL as the only isolate reported in 6 (46%). Five cases of SL isolates from urine specimens were reported, all of which with poor growth of bacteria and normal urinalysis. Two cases of SL growth in blood culture were found in children presenting with signs and symptoms consistent with invasive blood stream infection.Conclusions: In the paediatric population, studied infections caused by SL are increasingly observed. The results of this study highlight its role as a pathogen in soft tissue infections and its putative role in otitis media and invasive blood stream infections. However, the role of SL as an uropathogen was not established.

Multicenter retrospective cohort study of the clinical significance of Staphylococcus lugdunensis isolated from a single blood culture set.

BACKGROUND: Staphylococcus lugdunensis is a coagulase negative Staphylococcus species and frequent human skin commensal with the potential for aggressive infection. Guidance surrounding S. lugdunensis bacteremia (SLB) from a single set of blood cultures is lacking. METHODS: A multicenter, retrospective cohort of patients with SLB from at least one blood culture set within the University of Maryland Medical System from 2015 to 2019 is presented. Objectives are to describe baseline characteristics, compare the clinical status and treatment course, and to evaluate the clinical outcomes among patients with SLB in single versus multiple sets. RESULTS: Thirty-six patients were included, 24 with one set of blood cultures positive for S lugdunensis and 12 with multiple sets. Baseline characteristics were similar between the groups, though patients with SLB in multiple sets were more commonly on hemodialysis (P = 0.029). Central lines were the most common source (17%). Most (97%) fulfilled systemic inflammatory response syndrome or Souvenir criteria, had an infectious focus on imaging, or had a second positive culture site. Most (78%) were treated as clinically significant. Patients with multiple positive sets were more commonly treated with antibiotics for >2 weeks (P = 0.02). CONCLUSIONS: SLB was rare and occurred more frequently as a single set of positive cultures. Patient characteristics and clinical courses were similar between single and multiple set groups. Given the potential severity of S. lugdunensis bacteremia it seems prudent to treat S. lugdunensis in a single blood culture as true bacteremia, pending larger studies and guidelines.

Clinical Characteristics and Outcomes of Staphylococcus lugdunensis Prosthetic Joint Infections: A Multicenter Retrospective Analysis.

Staphylococcus lugdunensis has been increasingly recognized as a cause of serious infections, particularly prosthetic joint infections (PJIs). The aim of this study was to describe the clinical characteristics, treatments, and outcomes of S lugdunensis PJIs. This was a retrospective multicenter study of consecutive adult patients with S lugdunensis PJIs from January 2007 through December 2017; 28 patients met inclusion criteria. The knee was the most commonly affected joint (67.9%), followed by the hip (25%). Clinical and microbiologic characteristics, treatment modalities, and outcomes were evaluated. Thirteen (46.4%) patients had two-stage revision, 9 (32.1%) had debridement with or without revision, 5 (21.4%) had no surgical intervention, and 1 (3.6%) had one-stage revision. Twenty-four (85.7%) patients had monomicrobial infection with S lugdunensis, whereas 4 had polymicrobial. Two patients had concomitant bacteremia. All isolates, except 1, were susceptible to oxacillin. Three patients with no surgical intervention received oral antibiotics, 2 were not treated, and 1 was discharged to hospice. Relapse was observed in 2 of 13 (15%) patients who had two-stage revision, 4 of 9 (44%) who had debridement, and 6 of 6 (100%) who had no surgical intervention or one-stage revision regardless of antibiotic treatment regimen. There was a significant difference in cure rate for patients who underwent two-stage revision compared with other treatment modalities (85% vs 33%, P=.009). Appropriate management of S lugdunensis PJI includes both aggressive surgical treatment and a prolonged course of antibiotics and is associated with excellent clinical response. Regardless of route or duration of antibiotic therapy, relapse is high for patients not treated with two-stage revision. [Orthopedics. 2020;43(6):345-350.].

Cross-sectional study of Staphyloccus lugdunensis prevalence in cats.

Staphylococcus lugdunensis is a commensal bacterium in humans and other animals that can cause serious infections. The aim of this research was to estimate the frequency of S. lugdunensis in pet cats and to characterize the S. lugdunensis isolates obtained. The prevalence of S. lugdunensis was 0.77% (4/523) in healthy cats and 1.23% (1/81) in sick cats. The isolates (N = 5), which colonized conjunctival sacs, nares, and the anus, were almost fully phenotypically sensitive to antibiotics, but harbored resistance genes to four chemotherapeutic groups. Their sequence types (STs) included ST2, ST3, ST9, and ST15. There was detected a far lower prevalence of S. lugdunensis in pet cats than is reported in the human population. Nevertheless, the phenotypic and genotypic properties of S. lugdunensis isolates found in the current study were very similar to those described previously in isolates of human origin.

Epidemiology and antimicrobial susceptibility of Staphylococcus lugdunensis in a Greek tertiary-care hospital.

Staphylococcus lugdunensis is considered more pathogenic than other coagulase-negative Staphylococci (CoNS), with its virulence resembling that of Staphylococcus aureus. We report a retrospective study of all S. lugdunensis infection cases during a 3.5-year period in a large tertiary university hospital in Greece. S.lugdunensis was susceptible to most tested antibiotics, although a high resistance percentage was found to clindamycin (27%) and erythromycin (25%). The susceptibility rate to penicillin was 49%, much lower than previously reported elsewhere, indicating that penicillin may not be an optimal treatment choice for S. lugdunensis infections in our region.

Candida albicans and Staphylococcus lugdunensis superinfection of liver cysts in a patient with autosomal dominant polycystic kidney disease under prednisolone treatment.

We report a case of superinfection of liver cysts caused by Candida albicans and Staphylococcus lugdunensis in a patient with autosomal dominant polycystic kidney disease. A 69-year-old man with chief complaints of headache and blurred vision was admitted to the former institution for the evaluation of suspected temporal arteritis. He was prescribed oral prednisolone (55 mg/day) as a preemptive treatment; however, he became febrile and presented with bilateral flank pain during prednisolone tapering. Blood culture revealed fungemia as a result of Candida famata infection; thus, micafungin treatment was started. Thereafter, recrudescence of the C-reactive protein level ensued. Then a cyst infection as visualized on magnetic resonance imaging led to cyst aspiration sclerotherapy. Cyst aspirate culture revealed the presence of C. albicans in one of the cysts and S. lugdunensis in two of the cysts. The patient was clinically stabilized with an additional 3 weeks of antibiotic and antifungal drug administration.

Detection of sasX Gene and Distribution of SCCmec Types in Invasive and Non-invasive Coagulase-negative Staphylococci

Background: Coagulase-negative staphylococci, which belong to the normal microbiota of the skin and mucous membranes, are opportunistic pathogens. sasX, a newly described protein, is thought to play an important role in nasal colonization and methicillin-resistant Staphylococcus aureus virulence, and it may be acquired from coagulase-negative staphylococci by horizontal gene transfer. It has been considered that understanding the function of sasX gene may help clarify the relevance of the different adhesion mechanisms in the pathogenesis of infections associated with biofilm. Aims: To investigate the sasX gene presence, staphylococcal cassette chromosome mec types, and antimicrobial resistance patterns of invasive and noninvasive coagulase-negative staphylococci isolates. Study Design: Cross-sectional study. Methods: The study included a total of 180 coagulase-negative staphylococci strains. Non-invasive isolates (n=91) were obtained from the hands of healthy volunteers who do not work at the hospital (n=30), the nasal vestibule of healthy volunteer hospital workers (n=26), and central venous catheter (n=35). Invasive isolates (n=89) were isolated from peripheral blood cultures of inpatients who do not have catheters. All isolates were identified by conventional microbiological methods, automated systems, and, if needed, with matrix-assisted laser desorption/ionization-time of flight. Staphylococcal cassette chromosome mec typing, sasX and mec gene detection, antibiotic susceptibility, and sasX gene sequence analysis were performed. Results: Peripheral blood, central venous catheter colonization, and nasal vestibule isolates were positive for the sasX gene, whereas hand isolates were negative. sasX gene was present in 17 isolates, and no statistical significance was found between invasive and noninvasive isolates (p=0.173). Sequence analysis of the sasX genes showed high homology to related proteins of Staphylococcus phage SPbeta-like and Staphylococcus epidermidis RP62A. staphylococcal cassette chromosome mec type V was the most prevalent regardless of species. staphylococcal cassette chromosome mec type II was more frequent in invasive isolates and found to be statistically important for invasive and noninvasive S. epidermidis isolates (p=0.029). Staphylococcus haemolyticus isolates had the overall highest resistance rates. Resistance to ciprofloxacin, trimethoprim-sulfamethoxazole, and erythromycin was found to be higher in isolates from catheter and blood culture. Staphylococcus hominis isolates had the highest rate for inducible clindamycin resistance. None of the isolates were resistant to vancomycin, teicoplanin, and linezolid. Conclusion: The sasX gene is detected in 9.44% of the isolates. There is no statistical difference between the sasX-positive and -negative isolates in terms of antibacterial resistance and the presence of sasX and SCCmec types. Further studies about the role of sasX at virulence in coagulase-negative staphylococci, especially from clinical samples such as tracheal aspirate and abscess isolates, and distribution of staphylococcal cassette chromosome mec types are needed.

Significación clínica y aspectos microbiológicos para el diagnóstico de pacientes con Staphylococcus lugdunensis / Clinical significance and microbiological aspects for the diagnosis of patients with Staphylococcus lugdunensis

El Staphylococcus lugdunensis se manifiesta más como Staphylococcus aureus que como un típico estafilococo coagulasa negativa, especialmente por su gran virulencia y capacidad para producir infecciones supuradas. Debido al protagonismo creciente de esta especie, es propósito de esta investigación destacar la significación clínica y los aspectos microbiológicos para el diagnóstico de pacientes con dicha infección.

The Staphylococcus lugdunensis is manifested more as Staphylococcus aureus that as a typical negative coagulase staphylococcus, especially for its great virulence and capacity to produce suppurated infections. Due to the growing protagonism of this species, this investigation aims at highlighting the clinical significance and microbiological aspects for the diagnosis of patients with this infection.

Integron-Related Resistance in New Emerged Staphylococcus lugdunensis Infection in Burn Patients.

Staphylococcus lugdunensis is a coagulase-negative Staphylococcus species that may cause various infections with unusual severity. In spite of the administration of various antibiotics, infections caused by such bacteria are become resistant significantly. Transmission of antibiotic resistance genes, especially by Integron structures, exacerbates the prevalence of resistant strains. To investigate the antibiotic susceptibility pattern of S. lugdunensis as a new emergence in burns, the presence of integron classes (I, II, III) was performed in recent study. Sampling for this study was carried out over a period of 13 months (January 2017 to February 2018) from Amir-Al-Momenin burn center of southwest of Iran, affiliated with Shiraz University of Medical Sciences. Twenty-eight isolates of S. lugdunensis were confirmed by phenotypic tests. The presence of integron classes was evaluated by PCR technique and specific primers. The majority of studied infectious agents were seen in ICU with 28.57%. The prevalence of class I and II integrons was 7 (25.00%) and 2 (7.14%), respectively, in S. lugdunensis isolates, whereas no integron III was found. No significant association was seen between antibiotic resistance and the present integrons (P > .05). Since the prevalence of S. lugdunensis strains as a new emergence infection is increasing in clinical settings especially burns, preventing drug resistance in these isolates is inevitable. So knowing the epidemiology pattern of new emerging infections and their resistant pattern is very helpful in infection control and save hospitalized patients life.

Assisted Reproductive Technology as a Transcutaneous Route for Bacterial Contamination of Ovarian Endometrioma with Coagulase-Negative Staphylococcus: Case Report and Review of the Literature.

Tubo-ovarian abscess may develop in women with endometrioma following assisted reproductive technology (ART). The infection, though rare, is typically late in onset and may present several months after the procedure, and in pregnancy-with the risks of abortion and premature labor. It is thought that transcutaneous oocyte retrieval during ART is the route for bacterial contamination resulting in infection of the endometrioma. Pathogens reported in the literature include Escherichia coli (E. coli) and Group B streptococcus (GBS) but Staphylococcus lugdunensis (S. lugdunensis), a coagulase-negative staphylococcus (CoNS), and groin and perineal skin commensal was isolated from the endometrioma in this case. We discuss the challenges in diagnosis and treatment of this rare condition and the implications of the discovery that an organism previously dismissed as a contaminant has emerged as a causative organism in severe, deep-seated infections of soft tissues in recent literature.

Treatment of a Staphylococcus lugdunensis cervical epidural abscess.

First reported in 1988, Staphylococcus lugdunensis is a virulent coagulase-negative Staphylococcus species often associated with endocarditis. This is the first case report describing this infection in the cervical spine. A 58-year-old, left-handed Caucasian woman with no significant medical history presented with neck and left arm pain. Neurological examination revealed mild left deltoid 4/5 weakness and myelopathy. She was found to have an epidural cervical spinal cord mass that was causing severe cord compression and underwent partial anterior cervical decompression of the mass. On entering what was believed to be the mass, yellow-tinged fluid was encountered. An abscess was immediately suspected, so the dura was not entered. The specimen sent for culture was identified a day later as S. lugdunensis A two-dimensional echocardiogram was negative for vegetations. A peripherally inserted central catheter line was placed and the patient discharged on 6 weeks of physical therapy and 6-8 weeks of intravenous cefazolin.

Pediatric Case of Staphylococcus lugdunensis-Induced Infective Endocarditis at Bovine Jugular Vein.

A 2-year-old boy underwent repeat right ventricular outflow tract reconstruction (re-RVOTR) with a bovine jugular vein (BJV) graft. He presented with high fever on postoperative day 6. Blood and drainage effusion cultures were all positive for Staphylococcus lugdunensis and vancomycin was prescribed. Echocardiography showed vegetation at the BJV. Re-re-RVOTR was performed 51 days after re-RVOTR. In the operation, vegetation was adhered to the right-sided leaflet and three leaflets were degenerated. After complete BJV graft resection, an expanded polytetrafluoroethylene conduit with trileaflets was implanted. There was no sign of recurrent infection 8 months after the surgery.

Staphylococcus lugdunensis endophthalmitis following dexamethasone intravitreal implant.

We present a unique case of endophthalmitis with Staphylococcus lugdunensis following dexamethasone intravitreal implant for branch retinal vein occlusion associated with cystoid macular edema. Patient did not show favorable clinical response after vitrectomy and intravitreal antibiotics; so, we decided to repeat vitrectomy, remove the steroid implant and fill the eye with silicon oil, and repeat intravitreal vancomycin. Vision has improved from hand movements at presentation to counting fingers at 1.5 m after second vitrectomy and final visual acuity 3 months later after silicon oil removal was 6/36.

In vitro activity of tedizolid against clinical isolates of Staphylococcus lugdunensis and Staphylococcus haemolyticus from Europe and the United States.

Staphylococcus lugdunensis and Staphylococcus haemolyticus are unique among CoNS in that the former often causes aggressive disease, while the latter consistently exhibits high rates of multidrug resistance. We evaluated the in vitro susceptibility of contemporary (2012-2013) isolates from both pathogens to tedizolid and comparators, using standard methodology. Results were interpreted using CLSI and EUCAST breakpoints. Overall, 106 S. lugdunensis and 103 S. haemolyticus isolates were collected from 51 medical centers in the United States and 30 centers in 18 European countries. Tedizolid showed good activity against S. lugdunensis (MIC50/MIC90: 0.12/0.12 mg/L) and S. haemolyticus (MIC50/MIC90: 0.12/0.12 mg/L), inhibiting all isolates at MIC ≤0.25 mg/L. Based on the EUCAST breakpoint for staphylococci and when substituting the CLSI breakpoint for Staphylococcus aureus, all isolates were tedizolid susceptible. All isolates were also susceptible to linezolid, but the in vitro potency of tedizolid was 4-fold greater than that of linezolid against both S. lugdunensis and S. haemolyticus, based on MIC90 values. S. lugdunensis exhibited ≥99% susceptibility to vancomycin, teicoplanin, gentamicin, levofloxacin, and trimethoprim-sulfamethoxazole; 7% of isolates were resistant to tetracycline, 11% to clindamycin, and 2% were methicillin-resistant. S. haemolyticus exhibited high rates of resistance to commonly used anti-staphylococcal agents: 71% of isolates were resistant to methicillin, 36%-37% to clindamycin, and 30%-50% to gentamicin. These in vitro findings suggest that tedizolid could be an alternative treatment option for infections due to these medically important CoNS pathogens. Additional clinical evaluation and continued surveillance of tedizolid in vitro activity against S. lugdunensis and S. haemolyticus are warranted.