Panton-Valentine Leukocidin-Positive Staphylococcus aureus in Family and Pet Cat.

Continued detection of Panton-Valentine leukocidin-positive Staphylococcus aureus in samples from a family with severe repeated skin infections and their pet cat suggests transmission between the family and the cat. Decolonizing the pet led to successful elimination of the bacteria from the household. Clinicians should consider pet cats as possible reinfection sources.

CHROMAgar™ LIN-R as an efficient screening tool to assess the prevalence of linezolid-resistant enterococci in German hospital patients-a multicentre study approach, 2021-2022.

BACKGROUND: In recent years, an increasing number of linezolid-resistant enterococci (LRE) was recognized at the German National Reference Centre (NRC) for Enterococci. National guidelines on infection prevention recommend screening for LRE in epidemiologically linked hospital settings without referring to a reliable and rapid diagnostic method. Since 2020, CHROMAgar™ provide a chromogenic linezolid screening agar, LIN-R, suitable to simultaneously screen for linezolid-resistant staphylococci and enterococci. OBJECTIVES: To assess the applicability of CHROMAgar™ LIN-R in clinical settings for detecting LRE directly from patient material and to infer prevalence rates of LRE amongst German hospital patients. METHODS: During the 3-month trial period, clinical samples were plated on CHROMAgar™ LIN-R. Antimicrobial susceptibility testing was performed using VITEK2 or disc diffusion. At the NRC, linezolid resistance was determined by broth microdilution, multiplex-PCR for cfr/optrA/poxtA and by a restriction-based assay for 23S rDNA mutations. RESULTS: The 12 participating study sites used 13 963 CHROMAgar™ LIN-R plates during the study period. Of 442 presumptive LRE, 192 were confirmed by phenotypic methods. Of these, 161 were received by the NRC and 121 (75%) were verified as LRE. Most of LR-E. faecium 53/81 (65%) exhibited a 23S rRNA gene mutation as the sole resistance-mediating mechanism, whereas optrA constituted the dominant resistance trait in LR-E. faecalis [39/40 (98%)]. Prevalence of LRE across sites was estimated as 1% (ranging 0.18%-3.7% between sites). CONCLUSIONS: CHROMAgar™ LIN-R represents a simple and efficient LRE screening tool in hospital settings. A high proportion of false-positive results demands validation of linezolid resistance by a reference method.

Successful Therapy of a Multidrug-Resistant Extended-Spectrum ß-Lactamase-Producing and Fluoroquinolone-Resistant Salmonella enterica Subspecies enterica Serovar Typhi Infection Using Combination Therapy of Meropenem and Fosfomycin.

We report a traveler who acquired a Salmonella enterica subspecies enterica serovar Typhi strain with resistance against ß-lactams, cephalosporins (extended-spectrum ß-lactamase-producing type SHV-12), and quinolones (plasmid-mediated quinolone resistance gene qnrB7). After clinical deterioration using meropenem monotherapy, treatment success was achieved after commencement of fosfomycin in conjunction with high-dose meropenem. The case illustrates clinical challenges of multidrug-resistant S. Typhi.

Recurrent Chronic Obstructive Pulmonary Disease Exacerbations after Endobronchial Valve Implantation Are Associated with the Presence of Pseudomonas aeruginosa.

BACKGROUND: Endoscopic lung volume reduction by means of endobronchial valve implantation is an established therapy in patients with severe emphysema. However, long-term complications such as chronic obstructive pulmonary disease (COPD) exacerbations are a limitation of this method. OBJECTIVES: As the mechanisms underlying increased rates of COPD exacerbations are unknown, the aim of our study was to determine whether infectious or inflammatory factors may contribute to these events and to investingate the consequent need for valve explantation. METHODS: Tissue surrounding explanted endobronchial Zephyr valves was examined by microbiological, histological and cytological methods. Additionally, we performed a microbiological analysis of tracheal aspirates before both valve implantation and valve explantation. Moreover, blood samples were collected for the analysis of inflammatory markers. RESULTS: Endobronchial valves were explanted from 16 patients. Reasons for explantation were frequent postprocedural COPD exacerbations (group 1: 8 patients) or loss of clinical benefit (group 2: 8 patients). Compared to group 2, the microbiological examinations of valve lavage and tracheal aspirates from patients in group 1 showed a higher detection of Gram-negative bacteria. In particular, infection with Pseudomonas aeruginosa was more predominant in group 1, while no presence could be detected in group 2. Blood inflammatory markers tended to be slightly higher in group 1 than in group 2; however, without reaching statistical significance. CONCLUSIONS: Increased rates of COPD exacerbations after endobronchial valve implantation are associated with the presence of P. aeruginosa. The finding warrants further investigation.

Comparison of antibiotic prophylaxis with cotrimoxazole/colistin (COT/COL) versus ciprofloxacin (CIP) in patients with acute myeloid leukemia.

PURPOSE: Recent meta-analyses showed that antibiotic prophylaxis in patients with neutropenia after chemotherapy reduced the incidence of fever and mortality rate. Fluoroquinolones appear to be most effective and well tolerated. Thus, in April 2008, we changed our antibiotic prophylaxis regimen from cotrimoxazole/colistin (COT/COL) to the fluoroquinolone ciprofloxacin (CIP) in patients with acute myeloid leukemia (AML). The aim of this retrospective study was to compare efficacy and development of bacterial resistance with two different prophylaxis regimens over a time period of more than 4 years. METHODS: Induction chemotherapy courses given for AML during the antibiotic prophylaxis period with COT/COL (01/2006-04/2008) and CIP (04/2008-06/2010) were retrospectively analyzed with a standard questionnaire. RESULTS: Eighty-five courses in the COT/COL group and 105 in the CIP group were analyzed. The incidence of fever was not significantly different (COT/COL 80 % vs CIP 77 %; p = 0.724). Also, the rate of microbiologically documented infections was nearly the same (29 vs 26 %; p = 0.625). In addition, there was no significant difference in the incidence of clinically documented infections (11 vs 19 %; p = 0.155) or in the rates of detected gram-positive and gram-negative bacteria. Of note, there was no increase in resistance rates or cases with Clostridium difficile-associated diarrhea in the CIP group. CONCLUSION: The antibiotic prophylaxis with CIP compared to COT/COL in AML was similarly effective with no increase in bacterial resistance. COT/COL may have the advantages of providing additional prophylaxis against Pneumocystis jirovecii pneumonia and leaving fluoroquinolones as an additional option for treatment of febrile neutropenia.

Differentiation between Staphylococcus aureus and coagulase-negative Staphylococcus species by real-time PCR including detection of methicillin resistants in comparison to conventional microbiology testing.

BACKGROUND: Staphylococcus aureus has long been recognized as a major pathogen. Methicillin-resistant strains of S. aureus (MRSA) and methicillin-resistant strains of S. epidermidis (MRSE) are among the most prevalent multiresistant pathogens worldwide, frequently causing nosocomial and community-acquired infections. METHODS: In the present pilot study, we tested a polymerase chain reaction (PCR) method to quickly differentiate Staphylococci and identify the mecA gene in a clinical setting. RESULTS: Compared to the conventional microbiology testing the real-time PCR assay had a higher detection rate for both S. aureus and coagulase-negative Staphylococci (CoNS; 55 vs. 32 for S. aureus and 63 vs. 24 for CoNS). Hands-on time preparing DNA, carrying out the PCR, and evaluating results was less than 5 h. CONCLUSIONS: The assay is largely automated, easy to adapt, and has been shown to be rapid and reliable. Fast detection and differentiation of S. aureus, CoNS, and the mecA gene by means of this real-time PCR protocol may help expedite therapeutic decision-making and enable earlier adequate antibiotic treatment.

Evidence of MRSE on a gentamicin and vancomycin impregnated polymethyl-methacrylate (PMMA) bone cement spacer after two-stage exchange arthroplasty due to periprosthetic joint infection of the knee.

BACKGROUND: Periprosthetic joint infections (PJI) are often treated by two stage exchange with the use of an antibiotic impregnated spacer. Most of the two-stage exchange algorithms recommend the implantation of an antibiotic-impregnated spacer during the first stage for a period of 2-24 weeks before reimplantation of the new prosthesis. For the spacer to have a therapeutic effect, the local antibiotic concentration must be greater than the minimal inhibition concentration (MIC) against the pathogens causing the PJI. It must remain so for the entire spacer period, otherwise recurrence of infection or resistances might occur. The question as to whether a sufficient concentration of antibiotics in vivo is reached for the entire spacer period has not been answered satisfactorily. CASE PRESENTATION: We here present a case of a histologically confirmed chronic PJI 20 month after primary arthroplasty. The primary knee arthroplasty was performed due to osteoarthritis of the joint. Initial assessment did not detect a causative pathogen, and two stage exchange with a vancomycin-gentamycin impregnated spacer was performed. At the time of reimplantation, sonication of the explanted spacer revealed a multi-resistant strain of staphylococcus epidermidis on the device and in the joint. Adaption of the therapy and prolonged treatment successfully eradicated the infection. CONCLUSION: According to the authors' knowledge, the case presented here confirms for the first time the surface contamination (proven through sonication) of a vancomycin-/gentamicin- impregnated Vancogenx®-spacer with a MRSE after ten weeks of implantation.This case study demonstrates the difficulties still associated with the diagnostics of PJI and the published different two stage treatment regimes with the use of antibiotic impregnated spacers.

Microbiological Profiles of Patients with Spondylodiscitis.

Spondylodiscitis is a severe spinal infection that requires an effective antibiotic treatment. Therefore, we sought to analyse the causative pathogens from intraoperative specimen in patients with spondylodiscitis and a need for surgery. To this end, we performed a retrospective study of all patients with spondylodiscitis and a need for operative treatment admitted to our hospital between January 2020 and December 2022. A total of 114 cases with spondylodiscitis were identified. A total of 120 different pathogens were detected. Overall, 76.7% of those microorganisms were Gram-positive bacteria. The most common causative pathogen was Staphylococcus aureus (n = 32; 26.6%), followed by coagulase-negative staphylococci (n = 28; 23.4%), of which Staphylococcus epidermidis (n = 18; 15%) was the most frequently detected, as well as enterococci (n = 10; 8.4%) and Streptococcus spp. (n = 11; 9.2%). Moreover, 19.1% (n = 22) and 3.4% (n = 4) of all detected isolates were Gram-negative pathogens or fungi, respectively. Overall, 42.8% of all coagulase-negative staphylococci were oxacillin-resistant, while none of them were vancomycin-resistant. In summary, 50% of the pathogens could be identified as staphylococci. The results of our study highlight the important burden of oxacillin-resistant Gram-positive bacteria as an aetiological cause of spondylodiscitis, providing a relevant finding for antimicrobial stewardship programmes.

Chagas Disease: Comparison of Therapy with Nifurtimox and Benznidazole in Indigenous Communities in Colombia.

Background: For indigenous people in Colombia, high infection rates with Chagas disease (CD) are known. Methods: In 2018 and 2020, nine villages were screened for CD. CD-positive patients could enter a drug observed treatment. While, in 2018, Benznidazole (BNZ) was provided as the first-line drug by the government, nifurtimox (NFX) was administered in 2020. Results: Of 121 individuals treated with BNZ, 79 (65%) suffered from at least one adverse event (AE). Of 115 treated with NFX, at least one AE occurred in 96 (84%) patients. In 69% of BNZ cases, the side effects did not last longer than one day; this applied to 31% of NFX cases. Excluding extreme outlier values, average duration of AEs differed highly significantly: BNZ (M = 0.7, SD = 1.4) and NFX (M = 1.7, SD = 1.5, p < 0.001). Using an intensity scale, AEs were highly significantly more severe for NFX (M = 2.1, SD = 0.58) compared to BZN (M = 1.1, SD = 0.38), p < 0.001. When analyzing the duration in relation to the intensity, the burden of AEs caused by NFX was significantly more pronounced. Dropouts (n = 2) due to AEs were in the NFX-group only. Conclusions: Side effects caused by BNZ were significantly fewer, as well as milder, shorter in duration, and more easily treatable, compared to NFX.

In-depth analysis of the medical supply for indigenous people in North-Eastern Colombia: a dominance of infectious diseases and only insufficient therapeutic options.

BACKGROUND: Colombian indigenous Wiwas are exposed to a variety of partly complex medical conditions with a predominance of infectious diseases. The study provided here aims at verifying of falsifying previous suspicions on therapeutic shortcomings and neglect of disease categories. MATERIAL AND METHODS: Local diagnoses within various subpopulations of indigenous Wiwas obtained by a study physician and local health brigades and health points between 2017 and 2018 were coded following the ICD 10 classification from 2019. Proportions of diagnoses per ICD-10 sub-chapter were evaluated to find diseases and to rank the occurrence of diagnoses in the population of indigenous people. Thereafter, the available medication provided by the indigenous health care provider Dusakawi for the treatment of the indigenous patients was analyzed in regard of its sufficiency to cover the recorded diseases. RESULTS: The majority of the diseases found in the communities cannot at all (32%) or only partially (56%) be treated according to available guidelines. Only few (12%), predominantly infectious diseases, were covered completely by the provided medication. Notably, there are some ICD chapters with diseases that do only rarely appear at all in the gained datasets, e.g., complications during birth, mental disorders or cancer. CONCLUSIONS: An expansion and revision of the medical supply for the indigenous population of the Sierra Nevada de Santa Marta is needed. An emergency kit for medical brigades and health points should be provided and in place. Awareness for neglected diseases needs to be created.

Periprosthetic joint infection caused by kytococcus schroeteri: The first reported case and a review of the literature.

Oftentimes, Gram-positive cocci are the cause for periprosthetic joint infections (PJI). Most of these infections include bacteria such as Staphylococcus aureus, Staphylococcus epidermidis or other coagulase-negative staphylococci. We here present the first case of a PJI caused by Kytococcus schroeteri. While being a Gram-positive coccus, it is very rarely the cause for infections in the human body. K. schroeteri is part of the micrococcus branch and often encountered as a symbiotic bacterium living on the skin. Regarding its pathogenic potential, not a lot is known since less than a few dozen human infections have been reported worldwide. Furthermore, many of the cases reported are either associated with implanted material, especially heart valves, or associated with patients whose immune response is deficient. Only 3 reports of osteoarticular infections are described so far.

Gastrointestinal Pathogens in Multi-Infected Individuals: A Cluster Analysis of Interaction.

Indigenous people live in remote areas of Colombia. Multiple infections with bacteria, protozoa and/or helminths are common, as well as colonization in various forms. This study focused on the question of whether and to what extent various pathogens interact with each other. Therefore, a mathematical approach was retrospectively applied to PCR-based data of 244 stool samples, collected in two datasets. A stable cluster solution of the pathogens assessed was determined, and a unique configuration between Blastocystis hominis/Campylobacter spp./Giardia lamblia forming cluster 1 and Dientaemoeba fragilis was verified. A pathogen density-dependent interplay appeared between the B. hominis/Campylobacter spp./G. lamblia cluster, D. fragilis and Ascaris lumbricoides. The applied mathematical approach demonstrated that co-infections with parasites of questionable pathological relevance such as B. hominis and D. fragilis can be of diagnostic relevance due to their ability to promote or repress other pathogens. With the increasing availability of highly sensitive multiplexed molecular diagnostic approaches even in resource-limited settings, where multiple colonization of infection events with enteric pathogens in parallel are common, the importance of interpreting whole pathogen patterns rather than just individual pathogen detection may become more and more relevant.

Evaluation of an institutional guideline for the treatment of cerebrospinal fluid shunt-associated infections.

BACKGROUND: Cerebrospinal fluid (CSF) shunt-associated infection is one of the most frequent complications of CSF shunt surgery. We evaluated our institutional guideline for the treatment of shunt-associated infections. METHODS: We retrospectively analysed all 92 episodes of shunt-associated infections in 78 patients treated in our institution from 2002 to 2008. All patients underwent urgent surgery, i.e. removal of the complete shunt hardware or externalisation of the distal tubing in cases with an infection restricted to the distal shunt (10 %), placement of an external ventricular drainage as necessary and antibiotic therapy. Standard empirical first-line antibiotic treatment consisted of a combination of flucloxacillin and cefuroxime. RESULTS: We observed 38 % early (<1 month after shunt surgery) and 20 % late infections (> 1 year after shunt placement). Coagulase-negative staphylococci (CoNS) were isolated in 38 %. In 38 % no pathogens could be isolated. Of cases with a first shunt infection, 58 % were initially treated with flucloxacillin/cefuroxime. Only 53 % of all infections were treated successfully with the first course of antibiotics. Only 51 % of bacterial isolates were sensitive to empirical first-line antibiotics. Twenty percent of infections caused by sensitive bacterial isolates nevertheless required second-line antibiotic therapy. CONCLUSIONS: Urgent surgery for shunt removal and antibiotic therapy will usually cure a shunt-associated infection. The choice of antibiotics should reflect the spectrum of pathogens seen at one's institution, paying particular attention to the role of CoNS isolates, and in vitro sensitivity testing results.

Comparison of Empiric Antibiotic Escalation Therapy with Vancomycin (VAN) versus Linezolid (LIN) in Patients with Febrile Neutropenia.

Background: In febrile neutropenia, either linezolid (LIN) or vancomycin (VAN) can be used if a gram-positive infection is suspected. Interestingly there is no literature in which both are compared in the setting of febrile neutropenia. Therefore, we provide here the results of a retrospective analysis of adding VAN versus LIN in patients with febrile neutropenia. Methods: Patients with haematological diseases and febrile neutropenia after myelosuppressive chemotherapy and no clearance of infection after the first empiric broad-spectrum antibiotic were escalated to VAN or LIN from 03/2010 to 03/2014 at the University Hospital Bonn were included in this retrospective analysis. Results: Out of the 73 patients, 50 had received VAN and 23 LIN. The median hospitalisation time in the LIN cohort was significantly shorter than in the VAN cohort (LIN 16 days vs VAN 20 days p=0.046). Successful defervescence with the escalation to VAN or LIN could be detected in 76% of the LIN cases and 50% in the VAN group (p=0.052). This trend to better efficacy with LIN was also shown by a higher rate of discontinuation of VAN and escalation to another antibiotic scheme (54.2%) than in the LIN cohort (24%, p=0.052). Conclusion: The antibiotic therapy in febrile neutropenia with LIN showed a trend of better efficacy than therapy with VAN. However, because of the small sample size and the retrospective manner, VAN may still be considered a reasonable option in neutropenic fever, and randomised studies are needed in this field.

Microbiological Trends and Antibiotic Susceptibility Patterns in Patients with Periprosthetic Joint Infection of the Hip or Knee over 6 Years.

We sought to analyze trends of the causative pathogens and their antibiotic susceptibility patterns in patients with periprosthetic joint infections (PJI) of the hip and knee to get better insights and improve treatment. Retrospective evaluation of all consecutive patients with microbiological detection of a causative pathogen at a tertiary endoprothetic referral center between January 2016 and December 2021 in Germany was performed. Overall, 612 different microorganisms could be detected in 493 patients (hip: n = 293; knee: n = 200). Evaluation did not show a change in the relative abundance of pathogens detected, with coagulase-negative staphylococci (n = 275; 44.9%) found frequently, followed by S. aureus (n = 86; 14.1%), Enterococcus species (n = 57; 9.3%), Streptococcus species (n = 48; 7.8%), and Gram-negative bacteria (n = 80; 13.1%). Evaluation of the antibiotic susceptibilities showed increasing rates of oxacillin-resistant coagulase-negative staphylococci (60.4%; 46.8−76.7%) and piperacillin-tazobactam-resistant Gram-negative bacteria (26.5%; 0−57.1%), although statistically not significant. Resistance of Gram-positive bacteria to vancomycin (<1%) and Gram-negative microorganisms to meropenem (1.25%) remained an exception. In summary, coagulase-negative staphylococci, as the most frequent pathogen, displayed a continuously high rate of oxacillin resistance. For the highest antimicrobial coverage in the case of an empiric therapy/unknown pathogen, vancomycin might be chosen. Level of evidence: IV.

Microbiological Profiles of Patients with Periprosthetic Joint Infection of the Hip or Knee.

Periprosthetic joint infections (PJI) are one of the most devastating consequences after total joint arthroplasty. We sought to analyze the causative pathogens of patients with PJI to get better insights and improve treatment. We performed a retrospective study of all patients with PJI of the hip and knee with microbiological detection of a causative pathogen at a tertiary endoprothetic referral center between January 2016 and March 2021. A total of 432 cases with PJI (hip: n = 250; knee: n = 182) were included. The most common causative pathogen were coagulase-negative staphylococci (n = 240; 44.2%), of which Staphylococcus epidermidis (n = 144; 26.7%) was the most frequently detected, followed by S. aureus (n = 77; 14.3%) and enterococci (n = 49; 9%). Gram-negative pathogens and fungi could be detected in 21% (n = 136) and 2.4% (n = 13) of all cases. Overall, 60% of all coagulase-negative staphylococci were oxacillin-resistant, while none of these displayed to be vancomycin-resistant. In summary, the majority of pathogens in cases of PJI could be identified as coagulase-negative staphylococci. For empirical therapy vancomycin might provide the highest antimicrobial coverage in case of an unknown pathogen.