In vitro comparison of the effectiveness of various antimicrobial locks with taurolidine in the treatment and prevention of catheter-related bloodstream infections in patients receiving parenteral nutrition

OBJECTIVES

To evaluate the effectiveness of various taurolidine solutions in the prevention and treatment of catheter-related bloodstream infections (CRBSIs) caused by the entire spectrum of microbes in patients receiving parenteral nutrition in a shorter period of time.

METHODS

The in vitro method was used to test for eradication of biofilm. Different locks were used: TauroSept (2%), TauroLock (1.35%), TauroLock half concentration, and 3.5% taurolidine and tested on Staphylococcus (S.) epidermidis, S. aureus, S. hominis, methicillin-resistant S. aureus (MRSA), Pseudomonas (P.) aeruginosa (PSAE), multidrug-resistant P. aeruginosa (MR PSAE), vancomycin-resistant enterococci, Klebsiella pneumoniae producing carbapenemase (KPC), Klebsiella pneumoniae producing extended-spectrum beta-lactamase (KLPN ESBL), Candida (C.) albicans, and C. glabrata. Broviac catheters were incubated for growth of each organism and then incubated in lock solutions. Colony forming units (CFUs) were then counted after 30 min, 60 min, and 120 min of incubation.

RESULTS

A statistically significant decrease in CFUs was observed after 30 min of taurolidine exposure for S. hominis, PSAE, KLPN ESBL, KLPN KPC, C. albicans, and C. glabrata; after 60 min of exposure for S. epidermidis, PSAE, MR PSAE, KLPN ESBL, KPC, C. albicans, and C. glabrata; and after 120 min of exposure for S. epidermidis, S. hominis, S. aureus, PSAE, MR PSAE, KLPN ESBL, KPC, C. albicans, C. glabrata.

CONCLUSIONS

The application of taurolidine is effective in the treatment of CRBSIs. Taurolidine proved to be more effective against Gram-negative microorganisms during a 30-min exposure. Using 0.675% taurolidine is still effective. To achieve the required antimicrobial effect, the catheter must be sanitized for at least 2 h.

Dual Infection of an Open Fracture Caused by Mycobacterium setense and Clostridium celerecrescens

Infections caused by Mycobacterium setense or Clostridium celerecrescens are extremely rare. In this report, for the first time a dual infection with these two pathogens is described. An 18-year-old female suffered multiple injuries, including an open comminuted fracture of the right humeral diaphysis after falling from a fifth-floor balcony in January 2019. Five months after the accident, a fistula appeared in the scar, reaching the bone tissue. M. setense and C. celerecrescens were cultured from sinus swabs and subsequently from perioperative samples. The patient was initially treated with a combination of intravenous antibiotics (ATBs): imipenem, amikacin, and ciprofloxacin. One month after the fracture fixation with a titanium nail, C. celerecrescens was again detected; therefore, metronidazole was added to the therapy. A triple combination of oral (PO) ATBs (trimethoprim–sulfamethoxazole, moxifloxacin, and metronidazole) followed, 8 weeks after the initial intravenous therapy. C. celerecrescens was cultured again two times, most recently in November 2019, when surgical debridement was supplemented by the topical administration of cancellous bone impregnated with vancomycin. Signs of bone healing were found at follow-ups and ATB treatment was finished in March 2020 after a total of 9 months of therapy. To this day, there have been no signs of reinfection. This case thus illustrates the need for a combination of systemic and individualized local therapy in the treatment of complicated cases of dual infections with rare pathogens.

Evaluation of the risk factors of dental caries in children with very low birth weight and normal birth weight

Background

Health problems of premature infants can affect both general and oral health. The enamel defects, poor dietary and oral hygiene habits may predispose these children to dental caries. This study was conducted to assess the impact of very low birth weight and prematurity on caries risk in early childhood.

Methods

The study cohort consists of 189 of one year old infants. Anamnestic data were obtained from hospital records, feeding practice, bed-time sugar drinks and oral hygiene onset from questionnaires. Saliva samples of children and their mothers were collected for the detection of cariogenic pathogens.

Results

VLBW newborns had significantly shorter gestation age (29.6 vs. 38.8)) and lower mean birthweight (1124 g vs 3315 g) compared to NBW ones (p < 0.0001). Statistical significance has been found in the presence of early morbidity (p < 0.0001) and regular medication intake (p = 0.007). VLBW children got more frequently sweetened drinks during the day and night (p = 0.007). Regular oral hygiene practice was more frequent in full term group (p = 0.002). There was statistical difference in the presence of enamel hypoplasia in VLBW children (p = 0.033) but no statistical difference in the presence of hypomineralization (p = 0.0736) in comparison to NBW individuals. Proportional representation and count of S. mutans did not reveal statistical difference neither in both groups of children (p = 0.484) nor in both groups of mothers (p = 0.385).

Conclusions

The study confirmed anamnestic and medical differences between both groups. The proportional representation and count of S. mutans did not reveal statistical difference neither in VLBW and NBW children, nor in their mothers.

The association of a reduced susceptibility to moxifloxacin in causative Clostridium (Clostridioides) difficile strain with the clinical outcome of patients

OBJECTIVES

To investigate the relationship between Clostridium (Clostridioides) difficile strain characteristics and C. difficile infection (CDI) outcome.

METHODS

Between October and December 2017, 16 hospitals collected epidemiological data according to the European Centre for Disease Prevention and Control (ECDC) surveillance protocol for CDI. C. difficile isolates were characterized by ribotyping, toxin genes detection and antibiotic susceptibility testing to metronidazole, vancomycin and moxifloxacin.

RESULTS

The overall mean CDI incidence density was 4.5 [95% CI 3.6-5.3] cases per 10,000 patient-days. From the 433 CDI cases, 330 (76.2%) were healthcare-associated, 52 (12.0%) cases were community-associated or of unknown origin and 51 (11.8%) CDI cases recurrent; a complicated course of CDI was reported in 65 cases (15.0%). Eighty-eight (20.3%) of patients died and 59 of them within 30 days after the CDI diagnosis. From the 379 C. difficile isolates, the most prevalent PCR ribotypes were 001 (n = 127, 33.5%) and 176 (n = 44, 11.6%). A total of 186 (49.1%) isolates showed a reduced susceptibility to moxifloxacin (> 4 mg/L) and 96.4% of them had Thr82Ile in the GyrA. Nineteen isolates revealed reduced susceptibility to metronidazole and two isolates to vancomycin (> 2 mg/L). A fatal outcome was associated with a reduced susceptibility to moxifloxacin, the advanced age of the patients and a complicated course of CDI (p<0.05). No association between ribotype, binary toxin and a reduced susceptibility to moxifloxacin and complicated course or recurrent CDI was found.

CONCLUSIONS

A reduced susceptibility to moxifloxacin, in causative C. difficile strains was associated with fatal outcome of the patients, therefore it is an important marker in surveillance of CDI.

Isolation of Bordetella trematum from the respiratory tract of a patient with lung cancer: a case report

We report the case of isolation of Bordetella trematum from the respiratory tract of a patient with lung carcinoma. This gram-negative, opportunistic rod was firstly described in 1996. To date, only several strains of Bordetella trematum have been isolated and reported, mostly from skin and soft tissue infections. The patient was admitted to the ICU of the Pulmonary Department in incipient septic shock with respiratory failure. Intravenous fluid resuscitation and non-invasive ventilation were administered immediately. A broad spectrum antibiotic piperacillin/tazobactam was administered empirically after sampling of material for microbiological examination. The bronchoscopy showed a large cavern of decayed tumour invading into mediastinum. Both sample cultures showed significant quantities of gram-negative non-fermenting bacteria. The isolate was identified using MALDI-TOF MS as Bordetella trematum and the identification was confirmed using 16S ribosomal RNA sequencing. In the last few years, routine bacterial identification using MALDI-TOF MS has enabled correct discrimination of this species. Nevertheless, isolation of Bordetella trematum in clinical samples is still very uncommon, and it is appropriate to confirm the species identification via 16S ribosomal RNA sequencing. To our knowledge, this is the first case of B. trematum isolated from the human respiratory tract since its first description. The clinical significance of Bordetella trematum in the rapid deterioration of the patient's status remains unclear.

A rare case of purulent meningitis caused by Capnocytophaga canimorsus in the Czech Republic - case report and review of the literature

Background

Invasive infections caused by Capnocytophaga canimorsus are rare. Immunocompromised patients, who report being bitten by or having a close contact with an animal, represent a high-risk group for this infection. There are only few dozens of infections by this bacteria manifesting as purulent meningitis reported worldwide. The reported case is a first reported case of purulent meningitis caused by by Capnocytophaga canimorsus in Czech Republic with only a limited risk factor history.

Case presentation

The patient, a 74 years old man, was referred to the infectious diseases department of a teaching hospital with clear signs of developing purulent meningitis. His anamnestic data did not show any unusual findings. He was treated for compensated diabetes mellitus type II. The blood cultures were negative and the etiological agent did not grow from the cerebrospinal fluid (CSF) on common media. Eventually, it was identified by detecting pan-bacterial DNA and DNA sequencing. Subsequently, the pathogen was confirmed by anaerobic cultivation from CSF. Only after then the patient recalled being bitten by his German shepherd puppy during play. The patient was successfully treated intravenously by ceftriaxone.

Conclusions

Purulent meningitis caused by Capnocytophaga spp. is a rare disease, but it needs to be considered in patients at risk with pre-existing conditions, who report close contact with or being bitten by an animal. It is important to test for this microbe in cases with negative microbiological results for the more common agents.

In vitro comparison of efficacy of catheter locks in the treatment of catheter related blood stream infection

BACKGROUND & AIMS

Venous access used for parenteral nutrition (PN) application is extremely important for patients with intestinal failure. Potential loss of venous access might be a catastrophy for the patient. Catheter infections are a serious complication of PN application. Systemic administration of antibiotics as well as local antibiotic locks into the catheter to sterilize the catheter are used to treat catheter infections. However, there is no clear recommendation applying use of antibiotic locks, that would specify the type and concentration of antimicrobial medication. Our objective were to compare the efficacy of different types of antimicrobial lock therapy (especially taurolidine) and their concentrations to eradicate infectious agents.

METHODS

Bacterial strains of microorganisms (Staphylococcus epidermidis, Staphylococcus aureus, methicillin resistant S. aureus (MRSA), Pseudomonas aeruginosa, multidrug-resistant P. aeruginosa, Candida albicans) were used. Subsequently, the catheter was exposed to the microbes and then was incubated with a specific lock for 2 or 24 h at 37 °C. We used these locks: ethanol 70%, taurolidine, gentamicine in concentrations 0,5, 1 and 10 mg/ml and vancomycine in concentrations 1, 5, and 10 mg/ml. The number of remaining CFU (colony forming units) was compared after incubation.

RESULTS

70% ethanol and taurolidine were most effective for all studied microorganisms. Gentamicine was more effective than vancomycine.

CONCLUSIONS

The most effective antimicrobial lock solutions to eradicate selected pathogenic agents were ethanol and taurolidine. Use of antibiotics is often effective after many hours of treatment and there is a risk of inadequate therapy.

Elution kinetics of vancomycin and gentamicin from carriers and their effects on mesenchymal stem cell proliferation: an in vitro study

BACKGROUND

Musculoskeletal infections remain a major complication in orthopedic surgery. The local delivery of antibiotics provides the high levels required to treat an infection without systemic toxicity. However, the local toxicity of antibiotic carriers to the mesenchymal stem cells, as a result of both the peak concentrations and the type of carrier, may be significant.

METHODS

To address this concern, the elution kinetics of vancomycin and gentamicin from several commercially available antibiotic carriers and several carriers impregnated by a surgeon (10 ml of each sterile carrier were manually mixed with a 500 mg vancomycin and an 80 mg gentamicin solution, and the duration of impregnation was 30 min) were assessed. Moreover, the effects of these antibiotic carriers on stem cell proliferation were investigated. The following two types of stem cells were used: bone marrow and dental pulp stem cells.

RESULTS

The high eluted initial concentrations from antibiotic impregnated cancellous allogeneic bone grafts (which may be increased with the addition of fibrin glue) did not adversely affect stem cell proliferation. Moreover, an increased dental pulp stem cell proliferation rate in the presence of antibiotics was identified. In contrast to allogeneic bone grafts, a significant amount of antibiotics remained in the cement. Despite the favorable elution kinetics, the calcium carriers, bovine collagen carrier and freeze-dried bone exhibited decreased stem cell proliferation activity even in lower antibiotic concentrations compared with an allogeneic graft.

CONCLUSIONS

This study demonstrated the benefits of antibiotic impregnated cancellous allogeneic bone grafts versus other carriers.

Pyogenic sacroiliitis: diagnosis, management and clinical outcome

OBJECTIVE

The purpose of the present study was to evaluate the role of diagnostic tools and management options for patients with pyogenic sacroiliitis, including potential complications.

MATERIALS AND METHODS

This retrospective study included 16 patients with pyogenic sacroiliitis who were admitted to a single orthopaedic centre between 2007 and 2012. The following data were collected: demographics, history, radiography, magnetic resonance images (MRI), biological data, type of pathogenic agent, abscess formation, type of management, and clinical outcome.

RESULTS

Our study demonstrated that only one-fifth of the patients with lumbogluteal or hip pain had established diagnoses of suspected pyogenic sacroiliitis upon admission. MRIs confirmed this diagnosis in all cases. MRI examinations revealed joint fluid in the sacroiliac joint and significant oedema of the adjacent bone and soft tissues. In 12 of the 16 cases, erosions of the subchondral bone were encountered. Contrast-enhanced MRI revealed that 9 patients had abscesses. All patients received antibiotic therapy. Antibiotic treatment was only successful in 9 cases. The other 7 patients underwent computed tomography (CT)-guided abscess drainage. Drainage was sufficient for 4 patients, but 3 patients required open surgery. One patient required sacroiliac arthrodesis. The clinical outcomes included minimal disability (n = 10), moderate disability (n = 5), and full disability (n = 1) of the spine.

CONCLUSIONS

Contrast-enhanced MRI is mandatory for a reliable diagnosis. Abscess formation was observed in approximately half of the MRI-diagnosed sacroiliitis cases and required minimally invasive drainage under CT guidance or frequently open surgery.